1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * trace_events_hist - trace event hist triggers
4 *
5 * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com>
6 */
7
8 #include <linux/module.h>
9 #include <linux/kallsyms.h>
10 #include <linux/security.h>
11 #include <linux/mutex.h>
12 #include <linux/slab.h>
13 #include <linux/stacktrace.h>
14 #include <linux/rculist.h>
15 #include <linux/tracefs.h>
16
17 /* for gfp flag names */
18 #include <linux/trace_events.h>
19 #include <trace/events/mmflags.h>
20
21 #include "tracing_map.h"
22 #include "trace_synth.h"
23
24 #define ERRORS \
25 C(NONE, "No error"), \
26 C(DUPLICATE_VAR, "Variable already defined"), \
27 C(VAR_NOT_UNIQUE, "Variable name not unique, need to use fully qualified name (subsys.event.var) for variable"), \
28 C(TOO_MANY_VARS, "Too many variables defined"), \
29 C(MALFORMED_ASSIGNMENT, "Malformed assignment"), \
30 C(NAMED_MISMATCH, "Named hist trigger doesn't match existing named trigger (includes variables)"), \
31 C(TRIGGER_EEXIST, "Hist trigger already exists"), \
32 C(TRIGGER_ENOENT_CLEAR, "Can't clear or continue a nonexistent hist trigger"), \
33 C(SET_CLOCK_FAIL, "Couldn't set trace_clock"), \
34 C(BAD_FIELD_MODIFIER, "Invalid field modifier"), \
35 C(TOO_MANY_SUBEXPR, "Too many subexpressions (3 max)"), \
36 C(TIMESTAMP_MISMATCH, "Timestamp units in expression don't match"), \
37 C(TOO_MANY_FIELD_VARS, "Too many field variables defined"), \
38 C(EVENT_FILE_NOT_FOUND, "Event file not found"), \
39 C(HIST_NOT_FOUND, "Matching event histogram not found"), \
40 C(HIST_CREATE_FAIL, "Couldn't create histogram for field"), \
41 C(SYNTH_VAR_NOT_FOUND, "Couldn't find synthetic variable"), \
42 C(SYNTH_EVENT_NOT_FOUND,"Couldn't find synthetic event"), \
43 C(SYNTH_TYPE_MISMATCH, "Param type doesn't match synthetic event field type"), \
44 C(SYNTH_COUNT_MISMATCH, "Param count doesn't match synthetic event field count"), \
45 C(FIELD_VAR_PARSE_FAIL, "Couldn't parse field variable"), \
46 C(VAR_CREATE_FIND_FAIL, "Couldn't create or find variable"), \
47 C(ONX_NOT_VAR, "For onmax(x) or onchange(x), x must be a variable"), \
48 C(ONX_VAR_NOT_FOUND, "Couldn't find onmax or onchange variable"), \
49 C(ONX_VAR_CREATE_FAIL, "Couldn't create onmax or onchange variable"), \
50 C(FIELD_VAR_CREATE_FAIL,"Couldn't create field variable"), \
51 C(TOO_MANY_PARAMS, "Too many action params"), \
52 C(PARAM_NOT_FOUND, "Couldn't find param"), \
53 C(INVALID_PARAM, "Invalid action param"), \
54 C(ACTION_NOT_FOUND, "No action found"), \
55 C(NO_SAVE_PARAMS, "No params found for save()"), \
56 C(TOO_MANY_SAVE_ACTIONS,"Can't have more than one save() action per hist"), \
57 C(ACTION_MISMATCH, "Handler doesn't support action"), \
58 C(NO_CLOSING_PAREN, "No closing paren found"), \
59 C(SUBSYS_NOT_FOUND, "Missing subsystem"), \
60 C(INVALID_SUBSYS_EVENT, "Invalid subsystem or event name"), \
61 C(INVALID_REF_KEY, "Using variable references in keys not supported"), \
62 C(VAR_NOT_FOUND, "Couldn't find variable"), \
63 C(FIELD_NOT_FOUND, "Couldn't find field"), \
64 C(EMPTY_ASSIGNMENT, "Empty assignment"), \
65 C(INVALID_SORT_MODIFIER,"Invalid sort modifier"), \
66 C(EMPTY_SORT_FIELD, "Empty sort field"), \
67 C(TOO_MANY_SORT_FIELDS, "Too many sort fields (Max = 2)"), \
68 C(INVALID_SORT_FIELD, "Sort field must be a key or a val"), \
69 C(INVALID_STR_OPERAND, "String type can not be an operand in expression"), \
70 C(EXPECT_NUMBER, "Expecting numeric literal"), \
71 C(UNARY_MINUS_SUBEXPR, "Unary minus not supported in sub-expressions"), \
72 C(DIVISION_BY_ZERO, "Division by zero"),
73
74 #undef C
75 #define C(a, b) HIST_ERR_##a
76
77 enum { ERRORS };
78
79 #undef C
80 #define C(a, b) b
81
82 static const char *err_text[] = { ERRORS };
83
84 struct hist_field;
85
86 typedef u64 (*hist_field_fn_t) (struct hist_field *field,
87 struct tracing_map_elt *elt,
88 struct trace_buffer *buffer,
89 struct ring_buffer_event *rbe,
90 void *event);
91
92 #define HIST_FIELD_OPERANDS_MAX 2
93 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX)
94 #define HIST_ACTIONS_MAX 8
95 #define HIST_CONST_DIGITS_MAX 21
96 #define HIST_DIV_SHIFT 20 /* For optimizing division by constants */
97
98 enum field_op_id {
99 FIELD_OP_NONE,
100 FIELD_OP_PLUS,
101 FIELD_OP_MINUS,
102 FIELD_OP_UNARY_MINUS,
103 FIELD_OP_DIV,
104 FIELD_OP_MULT,
105 };
106
107 enum hist_field_fn {
108 HIST_FIELD_FN_NOP,
109 HIST_FIELD_FN_VAR_REF,
110 HIST_FIELD_FN_COUNTER,
111 HIST_FIELD_FN_CONST,
112 HIST_FIELD_FN_LOG2,
113 HIST_FIELD_FN_BUCKET,
114 HIST_FIELD_FN_TIMESTAMP,
115 HIST_FIELD_FN_CPU,
116 HIST_FIELD_FN_STRING,
117 HIST_FIELD_FN_DYNSTRING,
118 HIST_FIELD_FN_RELDYNSTRING,
119 HIST_FIELD_FN_PSTRING,
120 HIST_FIELD_FN_S64,
121 HIST_FIELD_FN_U64,
122 HIST_FIELD_FN_S32,
123 HIST_FIELD_FN_U32,
124 HIST_FIELD_FN_S16,
125 HIST_FIELD_FN_U16,
126 HIST_FIELD_FN_S8,
127 HIST_FIELD_FN_U8,
128 HIST_FIELD_FN_UMINUS,
129 HIST_FIELD_FN_MINUS,
130 HIST_FIELD_FN_PLUS,
131 HIST_FIELD_FN_DIV,
132 HIST_FIELD_FN_MULT,
133 HIST_FIELD_FN_DIV_POWER2,
134 HIST_FIELD_FN_DIV_NOT_POWER2,
135 HIST_FIELD_FN_DIV_MULT_SHIFT,
136 HIST_FIELD_FN_EXECNAME,
137 };
138
139 /*
140 * A hist_var (histogram variable) contains variable information for
141 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF
142 * flag set. A hist_var has a variable name e.g. ts0, and is
143 * associated with a given histogram trigger, as specified by
144 * hist_data. The hist_var idx is the unique index assigned to the
145 * variable by the hist trigger's tracing_map. The idx is what is
146 * used to set a variable's value and, by a variable reference, to
147 * retrieve it.
148 */
149 struct hist_var {
150 char *name;
151 struct hist_trigger_data *hist_data;
152 unsigned int idx;
153 };
154
155 struct hist_field {
156 struct ftrace_event_field *field;
157 unsigned long flags;
158 unsigned long buckets;
159 const char *type;
160 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX];
161 struct hist_trigger_data *hist_data;
162 enum hist_field_fn fn_num;
163 unsigned int ref;
164 unsigned int size;
165 unsigned int offset;
166 unsigned int is_signed;
167
168 /*
169 * Variable fields contain variable-specific info in var.
170 */
171 struct hist_var var;
172 enum field_op_id operator;
173 char *system;
174 char *event_name;
175
176 /*
177 * The name field is used for EXPR and VAR_REF fields. VAR
178 * fields contain the variable name in var.name.
179 */
180 char *name;
181
182 /*
183 * When a histogram trigger is hit, if it has any references
184 * to variables, the values of those variables are collected
185 * into a var_ref_vals array by resolve_var_refs(). The
186 * current value of each variable is read from the tracing_map
187 * using the hist field's hist_var.idx and entered into the
188 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx].
189 */
190 unsigned int var_ref_idx;
191 bool read_once;
192
193 unsigned int var_str_idx;
194
195 /* Numeric literals are represented as u64 */
196 u64 constant;
197 /* Used to optimize division by constants */
198 u64 div_multiplier;
199 };
200
201 static u64 hist_fn_call(struct hist_field *hist_field,
202 struct tracing_map_elt *elt,
203 struct trace_buffer *buffer,
204 struct ring_buffer_event *rbe,
205 void *event);
206
hist_field_const(struct hist_field * field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)207 static u64 hist_field_const(struct hist_field *field,
208 struct tracing_map_elt *elt,
209 struct trace_buffer *buffer,
210 struct ring_buffer_event *rbe,
211 void *event)
212 {
213 return field->constant;
214 }
215
hist_field_counter(struct hist_field * field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)216 static u64 hist_field_counter(struct hist_field *field,
217 struct tracing_map_elt *elt,
218 struct trace_buffer *buffer,
219 struct ring_buffer_event *rbe,
220 void *event)
221 {
222 return 1;
223 }
224
hist_field_string(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)225 static u64 hist_field_string(struct hist_field *hist_field,
226 struct tracing_map_elt *elt,
227 struct trace_buffer *buffer,
228 struct ring_buffer_event *rbe,
229 void *event)
230 {
231 char *addr = (char *)(event + hist_field->field->offset);
232
233 return (u64)(unsigned long)addr;
234 }
235
hist_field_dynstring(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)236 static u64 hist_field_dynstring(struct hist_field *hist_field,
237 struct tracing_map_elt *elt,
238 struct trace_buffer *buffer,
239 struct ring_buffer_event *rbe,
240 void *event)
241 {
242 u32 str_item = *(u32 *)(event + hist_field->field->offset);
243 int str_loc = str_item & 0xffff;
244 char *addr = (char *)(event + str_loc);
245
246 return (u64)(unsigned long)addr;
247 }
248
hist_field_reldynstring(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)249 static u64 hist_field_reldynstring(struct hist_field *hist_field,
250 struct tracing_map_elt *elt,
251 struct trace_buffer *buffer,
252 struct ring_buffer_event *rbe,
253 void *event)
254 {
255 u32 *item = event + hist_field->field->offset;
256 u32 str_item = *item;
257 int str_loc = str_item & 0xffff;
258 char *addr = (char *)&item[1] + str_loc;
259
260 return (u64)(unsigned long)addr;
261 }
262
hist_field_pstring(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)263 static u64 hist_field_pstring(struct hist_field *hist_field,
264 struct tracing_map_elt *elt,
265 struct trace_buffer *buffer,
266 struct ring_buffer_event *rbe,
267 void *event)
268 {
269 char **addr = (char **)(event + hist_field->field->offset);
270
271 return (u64)(unsigned long)*addr;
272 }
273
hist_field_log2(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)274 static u64 hist_field_log2(struct hist_field *hist_field,
275 struct tracing_map_elt *elt,
276 struct trace_buffer *buffer,
277 struct ring_buffer_event *rbe,
278 void *event)
279 {
280 struct hist_field *operand = hist_field->operands[0];
281
282 u64 val = hist_fn_call(operand, elt, buffer, rbe, event);
283
284 return (u64) ilog2(roundup_pow_of_two(val));
285 }
286
hist_field_bucket(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)287 static u64 hist_field_bucket(struct hist_field *hist_field,
288 struct tracing_map_elt *elt,
289 struct trace_buffer *buffer,
290 struct ring_buffer_event *rbe,
291 void *event)
292 {
293 struct hist_field *operand = hist_field->operands[0];
294 unsigned long buckets = hist_field->buckets;
295
296 u64 val = hist_fn_call(operand, elt, buffer, rbe, event);
297
298 if (WARN_ON_ONCE(!buckets))
299 return val;
300
301 if (val >= LONG_MAX)
302 val = div64_ul(val, buckets);
303 else
304 val = (u64)((unsigned long)val / buckets);
305 return val * buckets;
306 }
307
hist_field_plus(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)308 static u64 hist_field_plus(struct hist_field *hist_field,
309 struct tracing_map_elt *elt,
310 struct trace_buffer *buffer,
311 struct ring_buffer_event *rbe,
312 void *event)
313 {
314 struct hist_field *operand1 = hist_field->operands[0];
315 struct hist_field *operand2 = hist_field->operands[1];
316
317 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
318 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event);
319
320 return val1 + val2;
321 }
322
hist_field_minus(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)323 static u64 hist_field_minus(struct hist_field *hist_field,
324 struct tracing_map_elt *elt,
325 struct trace_buffer *buffer,
326 struct ring_buffer_event *rbe,
327 void *event)
328 {
329 struct hist_field *operand1 = hist_field->operands[0];
330 struct hist_field *operand2 = hist_field->operands[1];
331
332 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
333 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event);
334
335 return val1 - val2;
336 }
337
hist_field_div(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)338 static u64 hist_field_div(struct hist_field *hist_field,
339 struct tracing_map_elt *elt,
340 struct trace_buffer *buffer,
341 struct ring_buffer_event *rbe,
342 void *event)
343 {
344 struct hist_field *operand1 = hist_field->operands[0];
345 struct hist_field *operand2 = hist_field->operands[1];
346
347 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
348 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event);
349
350 /* Return -1 for the undefined case */
351 if (!val2)
352 return -1;
353
354 /* Use shift if the divisor is a power of 2 */
355 if (!(val2 & (val2 - 1)))
356 return val1 >> __ffs64(val2);
357
358 return div64_u64(val1, val2);
359 }
360
div_by_power_of_two(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)361 static u64 div_by_power_of_two(struct hist_field *hist_field,
362 struct tracing_map_elt *elt,
363 struct trace_buffer *buffer,
364 struct ring_buffer_event *rbe,
365 void *event)
366 {
367 struct hist_field *operand1 = hist_field->operands[0];
368 struct hist_field *operand2 = hist_field->operands[1];
369
370 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
371
372 return val1 >> __ffs64(operand2->constant);
373 }
374
div_by_not_power_of_two(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)375 static u64 div_by_not_power_of_two(struct hist_field *hist_field,
376 struct tracing_map_elt *elt,
377 struct trace_buffer *buffer,
378 struct ring_buffer_event *rbe,
379 void *event)
380 {
381 struct hist_field *operand1 = hist_field->operands[0];
382 struct hist_field *operand2 = hist_field->operands[1];
383
384 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
385
386 return div64_u64(val1, operand2->constant);
387 }
388
div_by_mult_and_shift(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)389 static u64 div_by_mult_and_shift(struct hist_field *hist_field,
390 struct tracing_map_elt *elt,
391 struct trace_buffer *buffer,
392 struct ring_buffer_event *rbe,
393 void *event)
394 {
395 struct hist_field *operand1 = hist_field->operands[0];
396 struct hist_field *operand2 = hist_field->operands[1];
397
398 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
399
400 /*
401 * If the divisor is a constant, do a multiplication and shift instead.
402 *
403 * Choose Z = some power of 2. If Y <= Z, then:
404 * X / Y = (X * (Z / Y)) / Z
405 *
406 * (Z / Y) is a constant (mult) which is calculated at parse time, so:
407 * X / Y = (X * mult) / Z
408 *
409 * The division by Z can be replaced by a shift since Z is a power of 2:
410 * X / Y = (X * mult) >> HIST_DIV_SHIFT
411 *
412 * As long, as X < Z the results will not be off by more than 1.
413 */
414 if (val1 < (1 << HIST_DIV_SHIFT)) {
415 u64 mult = operand2->div_multiplier;
416
417 return (val1 * mult + ((1 << HIST_DIV_SHIFT) - 1)) >> HIST_DIV_SHIFT;
418 }
419
420 return div64_u64(val1, operand2->constant);
421 }
422
hist_field_mult(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)423 static u64 hist_field_mult(struct hist_field *hist_field,
424 struct tracing_map_elt *elt,
425 struct trace_buffer *buffer,
426 struct ring_buffer_event *rbe,
427 void *event)
428 {
429 struct hist_field *operand1 = hist_field->operands[0];
430 struct hist_field *operand2 = hist_field->operands[1];
431
432 u64 val1 = hist_fn_call(operand1, elt, buffer, rbe, event);
433 u64 val2 = hist_fn_call(operand2, elt, buffer, rbe, event);
434
435 return val1 * val2;
436 }
437
hist_field_unary_minus(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)438 static u64 hist_field_unary_minus(struct hist_field *hist_field,
439 struct tracing_map_elt *elt,
440 struct trace_buffer *buffer,
441 struct ring_buffer_event *rbe,
442 void *event)
443 {
444 struct hist_field *operand = hist_field->operands[0];
445
446 s64 sval = (s64)hist_fn_call(operand, elt, buffer, rbe, event);
447 u64 val = (u64)-sval;
448
449 return val;
450 }
451
452 #define DEFINE_HIST_FIELD_FN(type) \
453 static u64 hist_field_##type(struct hist_field *hist_field, \
454 struct tracing_map_elt *elt, \
455 struct trace_buffer *buffer, \
456 struct ring_buffer_event *rbe, \
457 void *event) \
458 { \
459 type *addr = (type *)(event + hist_field->field->offset); \
460 \
461 return (u64)(unsigned long)*addr; \
462 }
463
464 DEFINE_HIST_FIELD_FN(s64);
465 DEFINE_HIST_FIELD_FN(u64);
466 DEFINE_HIST_FIELD_FN(s32);
467 DEFINE_HIST_FIELD_FN(u32);
468 DEFINE_HIST_FIELD_FN(s16);
469 DEFINE_HIST_FIELD_FN(u16);
470 DEFINE_HIST_FIELD_FN(s8);
471 DEFINE_HIST_FIELD_FN(u8);
472
473 #define for_each_hist_field(i, hist_data) \
474 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++)
475
476 #define for_each_hist_val_field(i, hist_data) \
477 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++)
478
479 #define for_each_hist_key_field(i, hist_data) \
480 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++)
481
482 #define HIST_STACKTRACE_DEPTH 16
483 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
484 #define HIST_STACKTRACE_SKIP 5
485
486 #define HITCOUNT_IDX 0
487 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE)
488
489 enum hist_field_flags {
490 HIST_FIELD_FL_HITCOUNT = 1 << 0,
491 HIST_FIELD_FL_KEY = 1 << 1,
492 HIST_FIELD_FL_STRING = 1 << 2,
493 HIST_FIELD_FL_HEX = 1 << 3,
494 HIST_FIELD_FL_SYM = 1 << 4,
495 HIST_FIELD_FL_SYM_OFFSET = 1 << 5,
496 HIST_FIELD_FL_EXECNAME = 1 << 6,
497 HIST_FIELD_FL_SYSCALL = 1 << 7,
498 HIST_FIELD_FL_STACKTRACE = 1 << 8,
499 HIST_FIELD_FL_LOG2 = 1 << 9,
500 HIST_FIELD_FL_TIMESTAMP = 1 << 10,
501 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11,
502 HIST_FIELD_FL_VAR = 1 << 12,
503 HIST_FIELD_FL_EXPR = 1 << 13,
504 HIST_FIELD_FL_VAR_REF = 1 << 14,
505 HIST_FIELD_FL_CPU = 1 << 15,
506 HIST_FIELD_FL_ALIAS = 1 << 16,
507 HIST_FIELD_FL_BUCKET = 1 << 17,
508 HIST_FIELD_FL_CONST = 1 << 18,
509 };
510
511 struct var_defs {
512 unsigned int n_vars;
513 char *name[TRACING_MAP_VARS_MAX];
514 char *expr[TRACING_MAP_VARS_MAX];
515 };
516
517 struct hist_trigger_attrs {
518 char *keys_str;
519 char *vals_str;
520 char *sort_key_str;
521 char *name;
522 char *clock;
523 bool pause;
524 bool cont;
525 bool clear;
526 bool ts_in_usecs;
527 unsigned int map_bits;
528
529 char *assignment_str[TRACING_MAP_VARS_MAX];
530 unsigned int n_assignments;
531
532 char *action_str[HIST_ACTIONS_MAX];
533 unsigned int n_actions;
534
535 struct var_defs var_defs;
536 };
537
538 struct field_var {
539 struct hist_field *var;
540 struct hist_field *val;
541 };
542
543 struct field_var_hist {
544 struct hist_trigger_data *hist_data;
545 char *cmd;
546 };
547
548 struct hist_trigger_data {
549 struct hist_field *fields[HIST_FIELDS_MAX];
550 unsigned int n_vals;
551 unsigned int n_keys;
552 unsigned int n_fields;
553 unsigned int n_vars;
554 unsigned int n_var_str;
555 unsigned int key_size;
556 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX];
557 unsigned int n_sort_keys;
558 struct trace_event_file *event_file;
559 struct hist_trigger_attrs *attrs;
560 struct tracing_map *map;
561 bool enable_timestamps;
562 bool remove;
563 struct hist_field *var_refs[TRACING_MAP_VARS_MAX];
564 unsigned int n_var_refs;
565
566 struct action_data *actions[HIST_ACTIONS_MAX];
567 unsigned int n_actions;
568
569 struct field_var *field_vars[SYNTH_FIELDS_MAX];
570 unsigned int n_field_vars;
571 unsigned int n_field_var_str;
572 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX];
573 unsigned int n_field_var_hists;
574
575 struct field_var *save_vars[SYNTH_FIELDS_MAX];
576 unsigned int n_save_vars;
577 unsigned int n_save_var_str;
578 };
579
580 struct action_data;
581
582 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data,
583 struct tracing_map_elt *elt,
584 struct trace_buffer *buffer, void *rec,
585 struct ring_buffer_event *rbe, void *key,
586 struct action_data *data, u64 *var_ref_vals);
587
588 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val);
589
590 enum handler_id {
591 HANDLER_ONMATCH = 1,
592 HANDLER_ONMAX,
593 HANDLER_ONCHANGE,
594 };
595
596 enum action_id {
597 ACTION_SAVE = 1,
598 ACTION_TRACE,
599 ACTION_SNAPSHOT,
600 };
601
602 struct action_data {
603 enum handler_id handler;
604 enum action_id action;
605 char *action_name;
606 action_fn_t fn;
607
608 unsigned int n_params;
609 char *params[SYNTH_FIELDS_MAX];
610
611 /*
612 * When a histogram trigger is hit, the values of any
613 * references to variables, including variables being passed
614 * as parameters to synthetic events, are collected into a
615 * var_ref_vals array. This var_ref_idx array is an array of
616 * indices into the var_ref_vals array, one for each synthetic
617 * event param, and is passed to the synthetic event
618 * invocation.
619 */
620 unsigned int var_ref_idx[TRACING_MAP_VARS_MAX];
621 struct synth_event *synth_event;
622 bool use_trace_keyword;
623 char *synth_event_name;
624
625 union {
626 struct {
627 char *event;
628 char *event_system;
629 } match_data;
630
631 struct {
632 /*
633 * var_str contains the $-unstripped variable
634 * name referenced by var_ref, and used when
635 * printing the action. Because var_ref
636 * creation is deferred to create_actions(),
637 * we need a per-action way to save it until
638 * then, thus var_str.
639 */
640 char *var_str;
641
642 /*
643 * var_ref refers to the variable being
644 * tracked e.g onmax($var).
645 */
646 struct hist_field *var_ref;
647
648 /*
649 * track_var contains the 'invisible' tracking
650 * variable created to keep the current
651 * e.g. max value.
652 */
653 struct hist_field *track_var;
654
655 check_track_val_fn_t check_val;
656 action_fn_t save_data;
657 } track_data;
658 };
659 };
660
661 struct track_data {
662 u64 track_val;
663 bool updated;
664
665 unsigned int key_len;
666 void *key;
667 struct tracing_map_elt elt;
668
669 struct action_data *action_data;
670 struct hist_trigger_data *hist_data;
671 };
672
673 struct hist_elt_data {
674 char *comm;
675 u64 *var_ref_vals;
676 char **field_var_str;
677 int n_field_var_str;
678 };
679
680 struct snapshot_context {
681 struct tracing_map_elt *elt;
682 void *key;
683 };
684
685 /*
686 * Returns the specific division function to use if the divisor
687 * is constant. This avoids extra branches when the trigger is hit.
688 */
hist_field_get_div_fn(struct hist_field * divisor)689 static enum hist_field_fn hist_field_get_div_fn(struct hist_field *divisor)
690 {
691 u64 div = divisor->constant;
692
693 if (!(div & (div - 1)))
694 return HIST_FIELD_FN_DIV_POWER2;
695
696 /* If the divisor is too large, do a regular division */
697 if (div > (1 << HIST_DIV_SHIFT))
698 return HIST_FIELD_FN_DIV_NOT_POWER2;
699
700 divisor->div_multiplier = div64_u64((u64)(1 << HIST_DIV_SHIFT), div);
701 return HIST_FIELD_FN_DIV_MULT_SHIFT;
702 }
703
track_data_free(struct track_data * track_data)704 static void track_data_free(struct track_data *track_data)
705 {
706 struct hist_elt_data *elt_data;
707
708 if (!track_data)
709 return;
710
711 kfree(track_data->key);
712
713 elt_data = track_data->elt.private_data;
714 if (elt_data) {
715 kfree(elt_data->comm);
716 kfree(elt_data);
717 }
718
719 kfree(track_data);
720 }
721
track_data_alloc(unsigned int key_len,struct action_data * action_data,struct hist_trigger_data * hist_data)722 static struct track_data *track_data_alloc(unsigned int key_len,
723 struct action_data *action_data,
724 struct hist_trigger_data *hist_data)
725 {
726 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL);
727 struct hist_elt_data *elt_data;
728
729 if (!data)
730 return ERR_PTR(-ENOMEM);
731
732 data->key = kzalloc(key_len, GFP_KERNEL);
733 if (!data->key) {
734 track_data_free(data);
735 return ERR_PTR(-ENOMEM);
736 }
737
738 data->key_len = key_len;
739 data->action_data = action_data;
740 data->hist_data = hist_data;
741
742 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
743 if (!elt_data) {
744 track_data_free(data);
745 return ERR_PTR(-ENOMEM);
746 }
747
748 data->elt.private_data = elt_data;
749
750 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL);
751 if (!elt_data->comm) {
752 track_data_free(data);
753 return ERR_PTR(-ENOMEM);
754 }
755
756 return data;
757 }
758
759 #define HIST_PREFIX "hist:"
760
761 static char *last_cmd;
762 static char last_cmd_loc[MAX_FILTER_STR_VAL];
763
errpos(char * str)764 static int errpos(char *str)
765 {
766 if (!str || !last_cmd)
767 return 0;
768
769 return err_pos(last_cmd, str);
770 }
771
last_cmd_set(struct trace_event_file * file,char * str)772 static void last_cmd_set(struct trace_event_file *file, char *str)
773 {
774 const char *system = NULL, *name = NULL;
775 struct trace_event_call *call;
776 int len;
777
778 if (!str)
779 return;
780
781 /* sizeof() contains the nul byte */
782 len = sizeof(HIST_PREFIX) + strlen(str);
783 kfree(last_cmd);
784 last_cmd = kzalloc(len, GFP_KERNEL);
785 if (!last_cmd)
786 return;
787
788 strcpy(last_cmd, HIST_PREFIX);
789 /* Again, sizeof() contains the nul byte */
790 len -= sizeof(HIST_PREFIX);
791 strncat(last_cmd, str, len);
792
793 if (file) {
794 call = file->event_call;
795 system = call->class->system;
796 if (system) {
797 name = trace_event_name(call);
798 if (!name)
799 system = NULL;
800 }
801 }
802
803 if (system)
804 snprintf(last_cmd_loc, MAX_FILTER_STR_VAL, HIST_PREFIX "%s:%s", system, name);
805 }
806
hist_err(struct trace_array * tr,u8 err_type,u16 err_pos)807 static void hist_err(struct trace_array *tr, u8 err_type, u16 err_pos)
808 {
809 if (!last_cmd)
810 return;
811
812 tracing_log_err(tr, last_cmd_loc, last_cmd, err_text,
813 err_type, err_pos);
814 }
815
hist_err_clear(void)816 static void hist_err_clear(void)
817 {
818 if (last_cmd)
819 last_cmd[0] = '\0';
820 last_cmd_loc[0] = '\0';
821 }
822
823 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals,
824 unsigned int *var_ref_idx);
825
trace_synth(struct synth_event * event,u64 * var_ref_vals,unsigned int * var_ref_idx)826 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals,
827 unsigned int *var_ref_idx)
828 {
829 struct tracepoint *tp = event->tp;
830
831 if (unlikely(atomic_read(&tp->key.enabled) > 0)) {
832 struct tracepoint_func *probe_func_ptr;
833 synth_probe_func_t probe_func;
834 void *__data;
835
836 if (!(cpu_online(raw_smp_processor_id())))
837 return;
838
839 probe_func_ptr = rcu_dereference_sched((tp)->funcs);
840 if (probe_func_ptr) {
841 do {
842 probe_func = probe_func_ptr->func;
843 __data = probe_func_ptr->data;
844 probe_func(__data, var_ref_vals, var_ref_idx);
845 } while ((++probe_func_ptr)->func);
846 }
847 }
848 }
849
action_trace(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct trace_buffer * buffer,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)850 static void action_trace(struct hist_trigger_data *hist_data,
851 struct tracing_map_elt *elt,
852 struct trace_buffer *buffer, void *rec,
853 struct ring_buffer_event *rbe, void *key,
854 struct action_data *data, u64 *var_ref_vals)
855 {
856 struct synth_event *event = data->synth_event;
857
858 trace_synth(event, var_ref_vals, data->var_ref_idx);
859 }
860
861 struct hist_var_data {
862 struct list_head list;
863 struct hist_trigger_data *hist_data;
864 };
865
hist_field_timestamp(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)866 static u64 hist_field_timestamp(struct hist_field *hist_field,
867 struct tracing_map_elt *elt,
868 struct trace_buffer *buffer,
869 struct ring_buffer_event *rbe,
870 void *event)
871 {
872 struct hist_trigger_data *hist_data = hist_field->hist_data;
873 struct trace_array *tr = hist_data->event_file->tr;
874
875 u64 ts = ring_buffer_event_time_stamp(buffer, rbe);
876
877 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr))
878 ts = ns2usecs(ts);
879
880 return ts;
881 }
882
hist_field_cpu(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)883 static u64 hist_field_cpu(struct hist_field *hist_field,
884 struct tracing_map_elt *elt,
885 struct trace_buffer *buffer,
886 struct ring_buffer_event *rbe,
887 void *event)
888 {
889 int cpu = smp_processor_id();
890
891 return cpu;
892 }
893
894 /**
895 * check_field_for_var_ref - Check if a VAR_REF field references a variable
896 * @hist_field: The VAR_REF field to check
897 * @var_data: The hist trigger that owns the variable
898 * @var_idx: The trigger variable identifier
899 *
900 * Check the given VAR_REF field to see whether or not it references
901 * the given variable associated with the given trigger.
902 *
903 * Return: The VAR_REF field if it does reference the variable, NULL if not
904 */
905 static struct hist_field *
check_field_for_var_ref(struct hist_field * hist_field,struct hist_trigger_data * var_data,unsigned int var_idx)906 check_field_for_var_ref(struct hist_field *hist_field,
907 struct hist_trigger_data *var_data,
908 unsigned int var_idx)
909 {
910 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF));
911
912 if (hist_field && hist_field->var.idx == var_idx &&
913 hist_field->var.hist_data == var_data)
914 return hist_field;
915
916 return NULL;
917 }
918
919 /**
920 * find_var_ref - Check if a trigger has a reference to a trigger variable
921 * @hist_data: The hist trigger that might have a reference to the variable
922 * @var_data: The hist trigger that owns the variable
923 * @var_idx: The trigger variable identifier
924 *
925 * Check the list of var_refs[] on the first hist trigger to see
926 * whether any of them are references to the variable on the second
927 * trigger.
928 *
929 * Return: The VAR_REF field referencing the variable if so, NULL if not
930 */
find_var_ref(struct hist_trigger_data * hist_data,struct hist_trigger_data * var_data,unsigned int var_idx)931 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data,
932 struct hist_trigger_data *var_data,
933 unsigned int var_idx)
934 {
935 struct hist_field *hist_field;
936 unsigned int i;
937
938 for (i = 0; i < hist_data->n_var_refs; i++) {
939 hist_field = hist_data->var_refs[i];
940 if (check_field_for_var_ref(hist_field, var_data, var_idx))
941 return hist_field;
942 }
943
944 return NULL;
945 }
946
947 /**
948 * find_any_var_ref - Check if there is a reference to a given trigger variable
949 * @hist_data: The hist trigger
950 * @var_idx: The trigger variable identifier
951 *
952 * Check to see whether the given variable is currently referenced by
953 * any other trigger.
954 *
955 * The trigger the variable is defined on is explicitly excluded - the
956 * assumption being that a self-reference doesn't prevent a trigger
957 * from being removed.
958 *
959 * Return: The VAR_REF field referencing the variable if so, NULL if not
960 */
find_any_var_ref(struct hist_trigger_data * hist_data,unsigned int var_idx)961 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data,
962 unsigned int var_idx)
963 {
964 struct trace_array *tr = hist_data->event_file->tr;
965 struct hist_field *found = NULL;
966 struct hist_var_data *var_data;
967
968 list_for_each_entry(var_data, &tr->hist_vars, list) {
969 if (var_data->hist_data == hist_data)
970 continue;
971 found = find_var_ref(var_data->hist_data, hist_data, var_idx);
972 if (found)
973 break;
974 }
975
976 return found;
977 }
978
979 /**
980 * check_var_refs - Check if there is a reference to any of trigger's variables
981 * @hist_data: The hist trigger
982 *
983 * A trigger can define one or more variables. If any one of them is
984 * currently referenced by any other trigger, this function will
985 * determine that.
986 *
987 * Typically used to determine whether or not a trigger can be removed
988 * - if there are any references to a trigger's variables, it cannot.
989 *
990 * Return: True if there is a reference to any of trigger's variables
991 */
check_var_refs(struct hist_trigger_data * hist_data)992 static bool check_var_refs(struct hist_trigger_data *hist_data)
993 {
994 struct hist_field *field;
995 bool found = false;
996 int i;
997
998 for_each_hist_field(i, hist_data) {
999 field = hist_data->fields[i];
1000 if (field && field->flags & HIST_FIELD_FL_VAR) {
1001 if (find_any_var_ref(hist_data, field->var.idx)) {
1002 found = true;
1003 break;
1004 }
1005 }
1006 }
1007
1008 return found;
1009 }
1010
find_hist_vars(struct hist_trigger_data * hist_data)1011 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data)
1012 {
1013 struct trace_array *tr = hist_data->event_file->tr;
1014 struct hist_var_data *var_data, *found = NULL;
1015
1016 list_for_each_entry(var_data, &tr->hist_vars, list) {
1017 if (var_data->hist_data == hist_data) {
1018 found = var_data;
1019 break;
1020 }
1021 }
1022
1023 return found;
1024 }
1025
field_has_hist_vars(struct hist_field * hist_field,unsigned int level)1026 static bool field_has_hist_vars(struct hist_field *hist_field,
1027 unsigned int level)
1028 {
1029 int i;
1030
1031 if (level > 3)
1032 return false;
1033
1034 if (!hist_field)
1035 return false;
1036
1037 if (hist_field->flags & HIST_FIELD_FL_VAR ||
1038 hist_field->flags & HIST_FIELD_FL_VAR_REF)
1039 return true;
1040
1041 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
1042 struct hist_field *operand;
1043
1044 operand = hist_field->operands[i];
1045 if (field_has_hist_vars(operand, level + 1))
1046 return true;
1047 }
1048
1049 return false;
1050 }
1051
has_hist_vars(struct hist_trigger_data * hist_data)1052 static bool has_hist_vars(struct hist_trigger_data *hist_data)
1053 {
1054 struct hist_field *hist_field;
1055 int i;
1056
1057 for_each_hist_field(i, hist_data) {
1058 hist_field = hist_data->fields[i];
1059 if (field_has_hist_vars(hist_field, 0))
1060 return true;
1061 }
1062
1063 return false;
1064 }
1065
save_hist_vars(struct hist_trigger_data * hist_data)1066 static int save_hist_vars(struct hist_trigger_data *hist_data)
1067 {
1068 struct trace_array *tr = hist_data->event_file->tr;
1069 struct hist_var_data *var_data;
1070
1071 var_data = find_hist_vars(hist_data);
1072 if (var_data)
1073 return 0;
1074
1075 if (tracing_check_open_get_tr(tr))
1076 return -ENODEV;
1077
1078 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL);
1079 if (!var_data) {
1080 trace_array_put(tr);
1081 return -ENOMEM;
1082 }
1083
1084 var_data->hist_data = hist_data;
1085 list_add(&var_data->list, &tr->hist_vars);
1086
1087 return 0;
1088 }
1089
remove_hist_vars(struct hist_trigger_data * hist_data)1090 static void remove_hist_vars(struct hist_trigger_data *hist_data)
1091 {
1092 struct trace_array *tr = hist_data->event_file->tr;
1093 struct hist_var_data *var_data;
1094
1095 var_data = find_hist_vars(hist_data);
1096 if (!var_data)
1097 return;
1098
1099 if (WARN_ON(check_var_refs(hist_data)))
1100 return;
1101
1102 list_del(&var_data->list);
1103
1104 kfree(var_data);
1105
1106 trace_array_put(tr);
1107 }
1108
find_var_field(struct hist_trigger_data * hist_data,const char * var_name)1109 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data,
1110 const char *var_name)
1111 {
1112 struct hist_field *hist_field, *found = NULL;
1113 int i;
1114
1115 for_each_hist_field(i, hist_data) {
1116 hist_field = hist_data->fields[i];
1117 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR &&
1118 strcmp(hist_field->var.name, var_name) == 0) {
1119 found = hist_field;
1120 break;
1121 }
1122 }
1123
1124 return found;
1125 }
1126
find_var(struct hist_trigger_data * hist_data,struct trace_event_file * file,const char * var_name)1127 static struct hist_field *find_var(struct hist_trigger_data *hist_data,
1128 struct trace_event_file *file,
1129 const char *var_name)
1130 {
1131 struct hist_trigger_data *test_data;
1132 struct event_trigger_data *test;
1133 struct hist_field *hist_field;
1134
1135 lockdep_assert_held(&event_mutex);
1136
1137 hist_field = find_var_field(hist_data, var_name);
1138 if (hist_field)
1139 return hist_field;
1140
1141 list_for_each_entry(test, &file->triggers, list) {
1142 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
1143 test_data = test->private_data;
1144 hist_field = find_var_field(test_data, var_name);
1145 if (hist_field)
1146 return hist_field;
1147 }
1148 }
1149
1150 return NULL;
1151 }
1152
find_var_file(struct trace_array * tr,char * system,char * event_name,char * var_name)1153 static struct trace_event_file *find_var_file(struct trace_array *tr,
1154 char *system,
1155 char *event_name,
1156 char *var_name)
1157 {
1158 struct hist_trigger_data *var_hist_data;
1159 struct hist_var_data *var_data;
1160 struct trace_event_file *file, *found = NULL;
1161
1162 if (system)
1163 return find_event_file(tr, system, event_name);
1164
1165 list_for_each_entry(var_data, &tr->hist_vars, list) {
1166 var_hist_data = var_data->hist_data;
1167 file = var_hist_data->event_file;
1168 if (file == found)
1169 continue;
1170
1171 if (find_var_field(var_hist_data, var_name)) {
1172 if (found) {
1173 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE, errpos(var_name));
1174 return NULL;
1175 }
1176
1177 found = file;
1178 }
1179 }
1180
1181 return found;
1182 }
1183
find_file_var(struct trace_event_file * file,const char * var_name)1184 static struct hist_field *find_file_var(struct trace_event_file *file,
1185 const char *var_name)
1186 {
1187 struct hist_trigger_data *test_data;
1188 struct event_trigger_data *test;
1189 struct hist_field *hist_field;
1190
1191 lockdep_assert_held(&event_mutex);
1192
1193 list_for_each_entry(test, &file->triggers, list) {
1194 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
1195 test_data = test->private_data;
1196 hist_field = find_var_field(test_data, var_name);
1197 if (hist_field)
1198 return hist_field;
1199 }
1200 }
1201
1202 return NULL;
1203 }
1204
1205 static struct hist_field *
find_match_var(struct hist_trigger_data * hist_data,char * var_name)1206 find_match_var(struct hist_trigger_data *hist_data, char *var_name)
1207 {
1208 struct trace_array *tr = hist_data->event_file->tr;
1209 struct hist_field *hist_field, *found = NULL;
1210 struct trace_event_file *file;
1211 unsigned int i;
1212
1213 for (i = 0; i < hist_data->n_actions; i++) {
1214 struct action_data *data = hist_data->actions[i];
1215
1216 if (data->handler == HANDLER_ONMATCH) {
1217 char *system = data->match_data.event_system;
1218 char *event_name = data->match_data.event;
1219
1220 file = find_var_file(tr, system, event_name, var_name);
1221 if (!file)
1222 continue;
1223 hist_field = find_file_var(file, var_name);
1224 if (hist_field) {
1225 if (found) {
1226 hist_err(tr, HIST_ERR_VAR_NOT_UNIQUE,
1227 errpos(var_name));
1228 return ERR_PTR(-EINVAL);
1229 }
1230
1231 found = hist_field;
1232 }
1233 }
1234 }
1235 return found;
1236 }
1237
find_event_var(struct hist_trigger_data * hist_data,char * system,char * event_name,char * var_name)1238 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data,
1239 char *system,
1240 char *event_name,
1241 char *var_name)
1242 {
1243 struct trace_array *tr = hist_data->event_file->tr;
1244 struct hist_field *hist_field = NULL;
1245 struct trace_event_file *file;
1246
1247 if (!system || !event_name) {
1248 hist_field = find_match_var(hist_data, var_name);
1249 if (IS_ERR(hist_field))
1250 return NULL;
1251 if (hist_field)
1252 return hist_field;
1253 }
1254
1255 file = find_var_file(tr, system, event_name, var_name);
1256 if (!file)
1257 return NULL;
1258
1259 hist_field = find_file_var(file, var_name);
1260
1261 return hist_field;
1262 }
1263
hist_field_var_ref(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)1264 static u64 hist_field_var_ref(struct hist_field *hist_field,
1265 struct tracing_map_elt *elt,
1266 struct trace_buffer *buffer,
1267 struct ring_buffer_event *rbe,
1268 void *event)
1269 {
1270 struct hist_elt_data *elt_data;
1271 u64 var_val = 0;
1272
1273 if (WARN_ON_ONCE(!elt))
1274 return var_val;
1275
1276 elt_data = elt->private_data;
1277 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx];
1278
1279 return var_val;
1280 }
1281
resolve_var_refs(struct hist_trigger_data * hist_data,void * key,u64 * var_ref_vals,bool self)1282 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key,
1283 u64 *var_ref_vals, bool self)
1284 {
1285 struct hist_trigger_data *var_data;
1286 struct tracing_map_elt *var_elt;
1287 struct hist_field *hist_field;
1288 unsigned int i, var_idx;
1289 bool resolved = true;
1290 u64 var_val = 0;
1291
1292 for (i = 0; i < hist_data->n_var_refs; i++) {
1293 hist_field = hist_data->var_refs[i];
1294 var_idx = hist_field->var.idx;
1295 var_data = hist_field->var.hist_data;
1296
1297 if (var_data == NULL) {
1298 resolved = false;
1299 break;
1300 }
1301
1302 if ((self && var_data != hist_data) ||
1303 (!self && var_data == hist_data))
1304 continue;
1305
1306 var_elt = tracing_map_lookup(var_data->map, key);
1307 if (!var_elt) {
1308 resolved = false;
1309 break;
1310 }
1311
1312 if (!tracing_map_var_set(var_elt, var_idx)) {
1313 resolved = false;
1314 break;
1315 }
1316
1317 if (self || !hist_field->read_once)
1318 var_val = tracing_map_read_var(var_elt, var_idx);
1319 else
1320 var_val = tracing_map_read_var_once(var_elt, var_idx);
1321
1322 var_ref_vals[i] = var_val;
1323 }
1324
1325 return resolved;
1326 }
1327
hist_field_name(struct hist_field * field,unsigned int level)1328 static const char *hist_field_name(struct hist_field *field,
1329 unsigned int level)
1330 {
1331 const char *field_name = "";
1332
1333 if (level > 1)
1334 return field_name;
1335
1336 if (field->field)
1337 field_name = field->field->name;
1338 else if (field->flags & HIST_FIELD_FL_LOG2 ||
1339 field->flags & HIST_FIELD_FL_ALIAS ||
1340 field->flags & HIST_FIELD_FL_BUCKET)
1341 field_name = hist_field_name(field->operands[0], ++level);
1342 else if (field->flags & HIST_FIELD_FL_CPU)
1343 field_name = "common_cpu";
1344 else if (field->flags & HIST_FIELD_FL_EXPR ||
1345 field->flags & HIST_FIELD_FL_VAR_REF) {
1346 if (field->system) {
1347 static char full_name[MAX_FILTER_STR_VAL];
1348
1349 strcat(full_name, field->system);
1350 strcat(full_name, ".");
1351 strcat(full_name, field->event_name);
1352 strcat(full_name, ".");
1353 strcat(full_name, field->name);
1354 field_name = full_name;
1355 } else
1356 field_name = field->name;
1357 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP)
1358 field_name = "common_timestamp";
1359
1360 if (field_name == NULL)
1361 field_name = "";
1362
1363 return field_name;
1364 }
1365
select_value_fn(int field_size,int field_is_signed)1366 static enum hist_field_fn select_value_fn(int field_size, int field_is_signed)
1367 {
1368 switch (field_size) {
1369 case 8:
1370 if (field_is_signed)
1371 return HIST_FIELD_FN_S64;
1372 else
1373 return HIST_FIELD_FN_U64;
1374 case 4:
1375 if (field_is_signed)
1376 return HIST_FIELD_FN_S32;
1377 else
1378 return HIST_FIELD_FN_U32;
1379 case 2:
1380 if (field_is_signed)
1381 return HIST_FIELD_FN_S16;
1382 else
1383 return HIST_FIELD_FN_U16;
1384 case 1:
1385 if (field_is_signed)
1386 return HIST_FIELD_FN_S8;
1387 else
1388 return HIST_FIELD_FN_U8;
1389 }
1390
1391 return HIST_FIELD_FN_NOP;
1392 }
1393
parse_map_size(char * str)1394 static int parse_map_size(char *str)
1395 {
1396 unsigned long size, map_bits;
1397 int ret;
1398
1399 ret = kstrtoul(str, 0, &size);
1400 if (ret)
1401 goto out;
1402
1403 map_bits = ilog2(roundup_pow_of_two(size));
1404 if (map_bits < TRACING_MAP_BITS_MIN ||
1405 map_bits > TRACING_MAP_BITS_MAX)
1406 ret = -EINVAL;
1407 else
1408 ret = map_bits;
1409 out:
1410 return ret;
1411 }
1412
destroy_hist_trigger_attrs(struct hist_trigger_attrs * attrs)1413 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
1414 {
1415 unsigned int i;
1416
1417 if (!attrs)
1418 return;
1419
1420 for (i = 0; i < attrs->n_assignments; i++)
1421 kfree(attrs->assignment_str[i]);
1422
1423 for (i = 0; i < attrs->n_actions; i++)
1424 kfree(attrs->action_str[i]);
1425
1426 kfree(attrs->name);
1427 kfree(attrs->sort_key_str);
1428 kfree(attrs->keys_str);
1429 kfree(attrs->vals_str);
1430 kfree(attrs->clock);
1431 kfree(attrs);
1432 }
1433
parse_action(char * str,struct hist_trigger_attrs * attrs)1434 static int parse_action(char *str, struct hist_trigger_attrs *attrs)
1435 {
1436 int ret = -EINVAL;
1437
1438 if (attrs->n_actions >= HIST_ACTIONS_MAX)
1439 return ret;
1440
1441 if ((str_has_prefix(str, "onmatch(")) ||
1442 (str_has_prefix(str, "onmax(")) ||
1443 (str_has_prefix(str, "onchange("))) {
1444 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL);
1445 if (!attrs->action_str[attrs->n_actions]) {
1446 ret = -ENOMEM;
1447 return ret;
1448 }
1449 attrs->n_actions++;
1450 ret = 0;
1451 }
1452 return ret;
1453 }
1454
parse_assignment(struct trace_array * tr,char * str,struct hist_trigger_attrs * attrs)1455 static int parse_assignment(struct trace_array *tr,
1456 char *str, struct hist_trigger_attrs *attrs)
1457 {
1458 int len, ret = 0;
1459
1460 if ((len = str_has_prefix(str, "key=")) ||
1461 (len = str_has_prefix(str, "keys="))) {
1462 attrs->keys_str = kstrdup(str + len, GFP_KERNEL);
1463 if (!attrs->keys_str) {
1464 ret = -ENOMEM;
1465 goto out;
1466 }
1467 } else if ((len = str_has_prefix(str, "val=")) ||
1468 (len = str_has_prefix(str, "vals=")) ||
1469 (len = str_has_prefix(str, "values="))) {
1470 attrs->vals_str = kstrdup(str + len, GFP_KERNEL);
1471 if (!attrs->vals_str) {
1472 ret = -ENOMEM;
1473 goto out;
1474 }
1475 } else if ((len = str_has_prefix(str, "sort="))) {
1476 attrs->sort_key_str = kstrdup(str + len, GFP_KERNEL);
1477 if (!attrs->sort_key_str) {
1478 ret = -ENOMEM;
1479 goto out;
1480 }
1481 } else if (str_has_prefix(str, "name=")) {
1482 attrs->name = kstrdup(str, GFP_KERNEL);
1483 if (!attrs->name) {
1484 ret = -ENOMEM;
1485 goto out;
1486 }
1487 } else if ((len = str_has_prefix(str, "clock="))) {
1488 str += len;
1489
1490 str = strstrip(str);
1491 attrs->clock = kstrdup(str, GFP_KERNEL);
1492 if (!attrs->clock) {
1493 ret = -ENOMEM;
1494 goto out;
1495 }
1496 } else if ((len = str_has_prefix(str, "size="))) {
1497 int map_bits = parse_map_size(str + len);
1498
1499 if (map_bits < 0) {
1500 ret = map_bits;
1501 goto out;
1502 }
1503 attrs->map_bits = map_bits;
1504 } else {
1505 char *assignment;
1506
1507 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) {
1508 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(str));
1509 ret = -EINVAL;
1510 goto out;
1511 }
1512
1513 assignment = kstrdup(str, GFP_KERNEL);
1514 if (!assignment) {
1515 ret = -ENOMEM;
1516 goto out;
1517 }
1518
1519 attrs->assignment_str[attrs->n_assignments++] = assignment;
1520 }
1521 out:
1522 return ret;
1523 }
1524
1525 static struct hist_trigger_attrs *
parse_hist_trigger_attrs(struct trace_array * tr,char * trigger_str)1526 parse_hist_trigger_attrs(struct trace_array *tr, char *trigger_str)
1527 {
1528 struct hist_trigger_attrs *attrs;
1529 int ret = 0;
1530
1531 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL);
1532 if (!attrs)
1533 return ERR_PTR(-ENOMEM);
1534
1535 while (trigger_str) {
1536 char *str = strsep(&trigger_str, ":");
1537 char *rhs;
1538
1539 rhs = strchr(str, '=');
1540 if (rhs) {
1541 if (!strlen(++rhs)) {
1542 ret = -EINVAL;
1543 hist_err(tr, HIST_ERR_EMPTY_ASSIGNMENT, errpos(str));
1544 goto free;
1545 }
1546 ret = parse_assignment(tr, str, attrs);
1547 if (ret)
1548 goto free;
1549 } else if (strcmp(str, "pause") == 0)
1550 attrs->pause = true;
1551 else if ((strcmp(str, "cont") == 0) ||
1552 (strcmp(str, "continue") == 0))
1553 attrs->cont = true;
1554 else if (strcmp(str, "clear") == 0)
1555 attrs->clear = true;
1556 else {
1557 ret = parse_action(str, attrs);
1558 if (ret)
1559 goto free;
1560 }
1561 }
1562
1563 if (!attrs->keys_str) {
1564 ret = -EINVAL;
1565 goto free;
1566 }
1567
1568 if (!attrs->clock) {
1569 attrs->clock = kstrdup("global", GFP_KERNEL);
1570 if (!attrs->clock) {
1571 ret = -ENOMEM;
1572 goto free;
1573 }
1574 }
1575
1576 return attrs;
1577 free:
1578 destroy_hist_trigger_attrs(attrs);
1579
1580 return ERR_PTR(ret);
1581 }
1582
save_comm(char * comm,struct task_struct * task)1583 static inline void save_comm(char *comm, struct task_struct *task)
1584 {
1585 if (!task->pid) {
1586 strcpy(comm, "<idle>");
1587 return;
1588 }
1589
1590 if (WARN_ON_ONCE(task->pid < 0)) {
1591 strcpy(comm, "<XXX>");
1592 return;
1593 }
1594
1595 strncpy(comm, task->comm, TASK_COMM_LEN);
1596 }
1597
hist_elt_data_free(struct hist_elt_data * elt_data)1598 static void hist_elt_data_free(struct hist_elt_data *elt_data)
1599 {
1600 unsigned int i;
1601
1602 for (i = 0; i < elt_data->n_field_var_str; i++)
1603 kfree(elt_data->field_var_str[i]);
1604
1605 kfree(elt_data->field_var_str);
1606
1607 kfree(elt_data->comm);
1608 kfree(elt_data);
1609 }
1610
hist_trigger_elt_data_free(struct tracing_map_elt * elt)1611 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt)
1612 {
1613 struct hist_elt_data *elt_data = elt->private_data;
1614
1615 hist_elt_data_free(elt_data);
1616 }
1617
hist_trigger_elt_data_alloc(struct tracing_map_elt * elt)1618 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
1619 {
1620 struct hist_trigger_data *hist_data = elt->map->private_data;
1621 unsigned int size = TASK_COMM_LEN;
1622 struct hist_elt_data *elt_data;
1623 struct hist_field *hist_field;
1624 unsigned int i, n_str;
1625
1626 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
1627 if (!elt_data)
1628 return -ENOMEM;
1629
1630 for_each_hist_field(i, hist_data) {
1631 hist_field = hist_data->fields[i];
1632
1633 if (hist_field->flags & HIST_FIELD_FL_EXECNAME) {
1634 elt_data->comm = kzalloc(size, GFP_KERNEL);
1635 if (!elt_data->comm) {
1636 kfree(elt_data);
1637 return -ENOMEM;
1638 }
1639 break;
1640 }
1641 }
1642
1643 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str +
1644 hist_data->n_var_str;
1645 if (n_str > SYNTH_FIELDS_MAX) {
1646 hist_elt_data_free(elt_data);
1647 return -EINVAL;
1648 }
1649
1650 BUILD_BUG_ON(STR_VAR_LEN_MAX & (sizeof(u64) - 1));
1651
1652 size = STR_VAR_LEN_MAX;
1653
1654 elt_data->field_var_str = kcalloc(n_str, sizeof(char *), GFP_KERNEL);
1655 if (!elt_data->field_var_str) {
1656 hist_elt_data_free(elt_data);
1657 return -EINVAL;
1658 }
1659 elt_data->n_field_var_str = n_str;
1660
1661 for (i = 0; i < n_str; i++) {
1662 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL);
1663 if (!elt_data->field_var_str[i]) {
1664 hist_elt_data_free(elt_data);
1665 return -ENOMEM;
1666 }
1667 }
1668
1669 elt->private_data = elt_data;
1670
1671 return 0;
1672 }
1673
hist_trigger_elt_data_init(struct tracing_map_elt * elt)1674 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt)
1675 {
1676 struct hist_elt_data *elt_data = elt->private_data;
1677
1678 if (elt_data->comm)
1679 save_comm(elt_data->comm, current);
1680 }
1681
1682 static const struct tracing_map_ops hist_trigger_elt_data_ops = {
1683 .elt_alloc = hist_trigger_elt_data_alloc,
1684 .elt_free = hist_trigger_elt_data_free,
1685 .elt_init = hist_trigger_elt_data_init,
1686 };
1687
get_hist_field_flags(struct hist_field * hist_field)1688 static const char *get_hist_field_flags(struct hist_field *hist_field)
1689 {
1690 const char *flags_str = NULL;
1691
1692 if (hist_field->flags & HIST_FIELD_FL_HEX)
1693 flags_str = "hex";
1694 else if (hist_field->flags & HIST_FIELD_FL_SYM)
1695 flags_str = "sym";
1696 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET)
1697 flags_str = "sym-offset";
1698 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME)
1699 flags_str = "execname";
1700 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL)
1701 flags_str = "syscall";
1702 else if (hist_field->flags & HIST_FIELD_FL_LOG2)
1703 flags_str = "log2";
1704 else if (hist_field->flags & HIST_FIELD_FL_BUCKET)
1705 flags_str = "buckets";
1706 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS)
1707 flags_str = "usecs";
1708
1709 return flags_str;
1710 }
1711
expr_field_str(struct hist_field * field,char * expr)1712 static void expr_field_str(struct hist_field *field, char *expr)
1713 {
1714 if (field->flags & HIST_FIELD_FL_VAR_REF)
1715 strcat(expr, "$");
1716 else if (field->flags & HIST_FIELD_FL_CONST) {
1717 char str[HIST_CONST_DIGITS_MAX];
1718
1719 snprintf(str, HIST_CONST_DIGITS_MAX, "%llu", field->constant);
1720 strcat(expr, str);
1721 }
1722
1723 strcat(expr, hist_field_name(field, 0));
1724
1725 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) {
1726 const char *flags_str = get_hist_field_flags(field);
1727
1728 if (flags_str) {
1729 strcat(expr, ".");
1730 strcat(expr, flags_str);
1731 }
1732 }
1733 }
1734
expr_str(struct hist_field * field,unsigned int level)1735 static char *expr_str(struct hist_field *field, unsigned int level)
1736 {
1737 char *expr;
1738
1739 if (level > 1)
1740 return NULL;
1741
1742 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
1743 if (!expr)
1744 return NULL;
1745
1746 if (!field->operands[0]) {
1747 expr_field_str(field, expr);
1748 return expr;
1749 }
1750
1751 if (field->operator == FIELD_OP_UNARY_MINUS) {
1752 char *subexpr;
1753
1754 strcat(expr, "-(");
1755 subexpr = expr_str(field->operands[0], ++level);
1756 if (!subexpr) {
1757 kfree(expr);
1758 return NULL;
1759 }
1760 strcat(expr, subexpr);
1761 strcat(expr, ")");
1762
1763 kfree(subexpr);
1764
1765 return expr;
1766 }
1767
1768 expr_field_str(field->operands[0], expr);
1769
1770 switch (field->operator) {
1771 case FIELD_OP_MINUS:
1772 strcat(expr, "-");
1773 break;
1774 case FIELD_OP_PLUS:
1775 strcat(expr, "+");
1776 break;
1777 case FIELD_OP_DIV:
1778 strcat(expr, "/");
1779 break;
1780 case FIELD_OP_MULT:
1781 strcat(expr, "*");
1782 break;
1783 default:
1784 kfree(expr);
1785 return NULL;
1786 }
1787
1788 expr_field_str(field->operands[1], expr);
1789
1790 return expr;
1791 }
1792
1793 /*
1794 * If field_op != FIELD_OP_NONE, *sep points to the root operator
1795 * of the expression tree to be evaluated.
1796 */
contains_operator(char * str,char ** sep)1797 static int contains_operator(char *str, char **sep)
1798 {
1799 enum field_op_id field_op = FIELD_OP_NONE;
1800 char *minus_op, *plus_op, *div_op, *mult_op;
1801
1802
1803 /*
1804 * Report the last occurrence of the operators first, so that the
1805 * expression is evaluated left to right. This is important since
1806 * subtraction and division are not associative.
1807 *
1808 * e.g
1809 * 64/8/4/2 is 1, i.e 64/8/4/2 = ((64/8)/4)/2
1810 * 14-7-5-2 is 0, i.e 14-7-5-2 = ((14-7)-5)-2
1811 */
1812
1813 /*
1814 * First, find lower precedence addition and subtraction
1815 * since the expression will be evaluated recursively.
1816 */
1817 minus_op = strrchr(str, '-');
1818 if (minus_op) {
1819 /*
1820 * Unary minus is not supported in sub-expressions. If
1821 * present, it is always the next root operator.
1822 */
1823 if (minus_op == str) {
1824 field_op = FIELD_OP_UNARY_MINUS;
1825 goto out;
1826 }
1827
1828 field_op = FIELD_OP_MINUS;
1829 }
1830
1831 plus_op = strrchr(str, '+');
1832 if (plus_op || minus_op) {
1833 /*
1834 * For operators of the same precedence use to rightmost as the
1835 * root, so that the expression is evaluated left to right.
1836 */
1837 if (plus_op > minus_op)
1838 field_op = FIELD_OP_PLUS;
1839 goto out;
1840 }
1841
1842 /*
1843 * Multiplication and division have higher precedence than addition and
1844 * subtraction.
1845 */
1846 div_op = strrchr(str, '/');
1847 if (div_op)
1848 field_op = FIELD_OP_DIV;
1849
1850 mult_op = strrchr(str, '*');
1851 /*
1852 * For operators of the same precedence use to rightmost as the
1853 * root, so that the expression is evaluated left to right.
1854 */
1855 if (mult_op > div_op)
1856 field_op = FIELD_OP_MULT;
1857
1858 out:
1859 if (sep) {
1860 switch (field_op) {
1861 case FIELD_OP_UNARY_MINUS:
1862 case FIELD_OP_MINUS:
1863 *sep = minus_op;
1864 break;
1865 case FIELD_OP_PLUS:
1866 *sep = plus_op;
1867 break;
1868 case FIELD_OP_DIV:
1869 *sep = div_op;
1870 break;
1871 case FIELD_OP_MULT:
1872 *sep = mult_op;
1873 break;
1874 case FIELD_OP_NONE:
1875 default:
1876 *sep = NULL;
1877 break;
1878 }
1879 }
1880
1881 return field_op;
1882 }
1883
get_hist_field(struct hist_field * hist_field)1884 static void get_hist_field(struct hist_field *hist_field)
1885 {
1886 hist_field->ref++;
1887 }
1888
__destroy_hist_field(struct hist_field * hist_field)1889 static void __destroy_hist_field(struct hist_field *hist_field)
1890 {
1891 if (--hist_field->ref > 1)
1892 return;
1893
1894 kfree(hist_field->var.name);
1895 kfree(hist_field->name);
1896
1897 /* Can likely be a const */
1898 kfree_const(hist_field->type);
1899
1900 kfree(hist_field->system);
1901 kfree(hist_field->event_name);
1902
1903 kfree(hist_field);
1904 }
1905
destroy_hist_field(struct hist_field * hist_field,unsigned int level)1906 static void destroy_hist_field(struct hist_field *hist_field,
1907 unsigned int level)
1908 {
1909 unsigned int i;
1910
1911 if (level > 3)
1912 return;
1913
1914 if (!hist_field)
1915 return;
1916
1917 if (hist_field->flags & HIST_FIELD_FL_VAR_REF)
1918 return; /* var refs will be destroyed separately */
1919
1920 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++)
1921 destroy_hist_field(hist_field->operands[i], level + 1);
1922
1923 __destroy_hist_field(hist_field);
1924 }
1925
create_hist_field(struct hist_trigger_data * hist_data,struct ftrace_event_field * field,unsigned long flags,char * var_name)1926 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
1927 struct ftrace_event_field *field,
1928 unsigned long flags,
1929 char *var_name)
1930 {
1931 struct hist_field *hist_field;
1932
1933 if (field && is_function_field(field))
1934 return NULL;
1935
1936 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
1937 if (!hist_field)
1938 return NULL;
1939
1940 hist_field->ref = 1;
1941
1942 hist_field->hist_data = hist_data;
1943
1944 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS)
1945 goto out; /* caller will populate */
1946
1947 if (flags & HIST_FIELD_FL_VAR_REF) {
1948 hist_field->fn_num = HIST_FIELD_FN_VAR_REF;
1949 goto out;
1950 }
1951
1952 if (flags & HIST_FIELD_FL_HITCOUNT) {
1953 hist_field->fn_num = HIST_FIELD_FN_COUNTER;
1954 hist_field->size = sizeof(u64);
1955 hist_field->type = "u64";
1956 goto out;
1957 }
1958
1959 if (flags & HIST_FIELD_FL_CONST) {
1960 hist_field->fn_num = HIST_FIELD_FN_CONST;
1961 hist_field->size = sizeof(u64);
1962 hist_field->type = kstrdup("u64", GFP_KERNEL);
1963 if (!hist_field->type)
1964 goto free;
1965 goto out;
1966 }
1967
1968 if (flags & HIST_FIELD_FL_STACKTRACE) {
1969 hist_field->fn_num = HIST_FIELD_FN_NOP;
1970 goto out;
1971 }
1972
1973 if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) {
1974 unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET);
1975 hist_field->fn_num = flags & HIST_FIELD_FL_LOG2 ? HIST_FIELD_FN_LOG2 :
1976 HIST_FIELD_FN_BUCKET;
1977 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL);
1978 hist_field->size = hist_field->operands[0]->size;
1979 hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL);
1980 if (!hist_field->type)
1981 goto free;
1982 goto out;
1983 }
1984
1985 if (flags & HIST_FIELD_FL_TIMESTAMP) {
1986 hist_field->fn_num = HIST_FIELD_FN_TIMESTAMP;
1987 hist_field->size = sizeof(u64);
1988 hist_field->type = "u64";
1989 goto out;
1990 }
1991
1992 if (flags & HIST_FIELD_FL_CPU) {
1993 hist_field->fn_num = HIST_FIELD_FN_CPU;
1994 hist_field->size = sizeof(int);
1995 hist_field->type = "unsigned int";
1996 goto out;
1997 }
1998
1999 if (WARN_ON_ONCE(!field))
2000 goto out;
2001
2002 /* Pointers to strings are just pointers and dangerous to dereference */
2003 if (is_string_field(field) &&
2004 (field->filter_type != FILTER_PTR_STRING)) {
2005 flags |= HIST_FIELD_FL_STRING;
2006
2007 hist_field->size = MAX_FILTER_STR_VAL;
2008 hist_field->type = kstrdup_const(field->type, GFP_KERNEL);
2009 if (!hist_field->type)
2010 goto free;
2011
2012 if (field->filter_type == FILTER_STATIC_STRING) {
2013 hist_field->fn_num = HIST_FIELD_FN_STRING;
2014 hist_field->size = field->size;
2015 } else if (field->filter_type == FILTER_DYN_STRING) {
2016 hist_field->fn_num = HIST_FIELD_FN_DYNSTRING;
2017 } else if (field->filter_type == FILTER_RDYN_STRING)
2018 hist_field->fn_num = HIST_FIELD_FN_RELDYNSTRING;
2019 else
2020 hist_field->fn_num = HIST_FIELD_FN_PSTRING;
2021 } else {
2022 hist_field->size = field->size;
2023 hist_field->is_signed = field->is_signed;
2024 hist_field->type = kstrdup_const(field->type, GFP_KERNEL);
2025 if (!hist_field->type)
2026 goto free;
2027
2028 hist_field->fn_num = select_value_fn(field->size,
2029 field->is_signed);
2030 if (hist_field->fn_num == HIST_FIELD_FN_NOP) {
2031 destroy_hist_field(hist_field, 0);
2032 return NULL;
2033 }
2034 }
2035 out:
2036 hist_field->field = field;
2037 hist_field->flags = flags;
2038
2039 if (var_name) {
2040 hist_field->var.name = kstrdup(var_name, GFP_KERNEL);
2041 if (!hist_field->var.name)
2042 goto free;
2043 }
2044
2045 return hist_field;
2046 free:
2047 destroy_hist_field(hist_field, 0);
2048 return NULL;
2049 }
2050
destroy_hist_fields(struct hist_trigger_data * hist_data)2051 static void destroy_hist_fields(struct hist_trigger_data *hist_data)
2052 {
2053 unsigned int i;
2054
2055 for (i = 0; i < HIST_FIELDS_MAX; i++) {
2056 if (hist_data->fields[i]) {
2057 destroy_hist_field(hist_data->fields[i], 0);
2058 hist_data->fields[i] = NULL;
2059 }
2060 }
2061
2062 for (i = 0; i < hist_data->n_var_refs; i++) {
2063 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF));
2064 __destroy_hist_field(hist_data->var_refs[i]);
2065 hist_data->var_refs[i] = NULL;
2066 }
2067 }
2068
init_var_ref(struct hist_field * ref_field,struct hist_field * var_field,char * system,char * event_name)2069 static int init_var_ref(struct hist_field *ref_field,
2070 struct hist_field *var_field,
2071 char *system, char *event_name)
2072 {
2073 int err = 0;
2074
2075 ref_field->var.idx = var_field->var.idx;
2076 ref_field->var.hist_data = var_field->hist_data;
2077 ref_field->size = var_field->size;
2078 ref_field->is_signed = var_field->is_signed;
2079 ref_field->flags |= var_field->flags &
2080 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2081
2082 if (system) {
2083 ref_field->system = kstrdup(system, GFP_KERNEL);
2084 if (!ref_field->system)
2085 return -ENOMEM;
2086 }
2087
2088 if (event_name) {
2089 ref_field->event_name = kstrdup(event_name, GFP_KERNEL);
2090 if (!ref_field->event_name) {
2091 err = -ENOMEM;
2092 goto free;
2093 }
2094 }
2095
2096 if (var_field->var.name) {
2097 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL);
2098 if (!ref_field->name) {
2099 err = -ENOMEM;
2100 goto free;
2101 }
2102 } else if (var_field->name) {
2103 ref_field->name = kstrdup(var_field->name, GFP_KERNEL);
2104 if (!ref_field->name) {
2105 err = -ENOMEM;
2106 goto free;
2107 }
2108 }
2109
2110 ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL);
2111 if (!ref_field->type) {
2112 err = -ENOMEM;
2113 goto free;
2114 }
2115 out:
2116 return err;
2117 free:
2118 kfree(ref_field->system);
2119 ref_field->system = NULL;
2120 kfree(ref_field->event_name);
2121 ref_field->event_name = NULL;
2122 kfree(ref_field->name);
2123 ref_field->name = NULL;
2124
2125 goto out;
2126 }
2127
find_var_ref_idx(struct hist_trigger_data * hist_data,struct hist_field * var_field)2128 static int find_var_ref_idx(struct hist_trigger_data *hist_data,
2129 struct hist_field *var_field)
2130 {
2131 struct hist_field *ref_field;
2132 int i;
2133
2134 for (i = 0; i < hist_data->n_var_refs; i++) {
2135 ref_field = hist_data->var_refs[i];
2136 if (ref_field->var.idx == var_field->var.idx &&
2137 ref_field->var.hist_data == var_field->hist_data)
2138 return i;
2139 }
2140
2141 return -ENOENT;
2142 }
2143
2144 /**
2145 * create_var_ref - Create a variable reference and attach it to trigger
2146 * @hist_data: The trigger that will be referencing the variable
2147 * @var_field: The VAR field to create a reference to
2148 * @system: The optional system string
2149 * @event_name: The optional event_name string
2150 *
2151 * Given a variable hist_field, create a VAR_REF hist_field that
2152 * represents a reference to it.
2153 *
2154 * This function also adds the reference to the trigger that
2155 * now references the variable.
2156 *
2157 * Return: The VAR_REF field if successful, NULL if not
2158 */
create_var_ref(struct hist_trigger_data * hist_data,struct hist_field * var_field,char * system,char * event_name)2159 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data,
2160 struct hist_field *var_field,
2161 char *system, char *event_name)
2162 {
2163 unsigned long flags = HIST_FIELD_FL_VAR_REF;
2164 struct hist_field *ref_field;
2165 int i;
2166
2167 /* Check if the variable already exists */
2168 for (i = 0; i < hist_data->n_var_refs; i++) {
2169 ref_field = hist_data->var_refs[i];
2170 if (ref_field->var.idx == var_field->var.idx &&
2171 ref_field->var.hist_data == var_field->hist_data) {
2172 get_hist_field(ref_field);
2173 return ref_field;
2174 }
2175 }
2176
2177 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL);
2178 if (ref_field) {
2179 if (init_var_ref(ref_field, var_field, system, event_name)) {
2180 destroy_hist_field(ref_field, 0);
2181 return NULL;
2182 }
2183
2184 hist_data->var_refs[hist_data->n_var_refs] = ref_field;
2185 ref_field->var_ref_idx = hist_data->n_var_refs++;
2186 }
2187
2188 return ref_field;
2189 }
2190
is_var_ref(char * var_name)2191 static bool is_var_ref(char *var_name)
2192 {
2193 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$')
2194 return false;
2195
2196 return true;
2197 }
2198
field_name_from_var(struct hist_trigger_data * hist_data,char * var_name)2199 static char *field_name_from_var(struct hist_trigger_data *hist_data,
2200 char *var_name)
2201 {
2202 char *name, *field;
2203 unsigned int i;
2204
2205 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
2206 name = hist_data->attrs->var_defs.name[i];
2207
2208 if (strcmp(var_name, name) == 0) {
2209 field = hist_data->attrs->var_defs.expr[i];
2210 if (contains_operator(field, NULL) || is_var_ref(field))
2211 continue;
2212 return field;
2213 }
2214 }
2215
2216 return NULL;
2217 }
2218
local_field_var_ref(struct hist_trigger_data * hist_data,char * system,char * event_name,char * var_name)2219 static char *local_field_var_ref(struct hist_trigger_data *hist_data,
2220 char *system, char *event_name,
2221 char *var_name)
2222 {
2223 struct trace_event_call *call;
2224
2225 if (system && event_name) {
2226 call = hist_data->event_file->event_call;
2227
2228 if (strcmp(system, call->class->system) != 0)
2229 return NULL;
2230
2231 if (strcmp(event_name, trace_event_name(call)) != 0)
2232 return NULL;
2233 }
2234
2235 if (!!system != !!event_name)
2236 return NULL;
2237
2238 if (!is_var_ref(var_name))
2239 return NULL;
2240
2241 var_name++;
2242
2243 return field_name_from_var(hist_data, var_name);
2244 }
2245
parse_var_ref(struct hist_trigger_data * hist_data,char * system,char * event_name,char * var_name)2246 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data,
2247 char *system, char *event_name,
2248 char *var_name)
2249 {
2250 struct hist_field *var_field = NULL, *ref_field = NULL;
2251 struct trace_array *tr = hist_data->event_file->tr;
2252
2253 if (!is_var_ref(var_name))
2254 return NULL;
2255
2256 var_name++;
2257
2258 var_field = find_event_var(hist_data, system, event_name, var_name);
2259 if (var_field)
2260 ref_field = create_var_ref(hist_data, var_field,
2261 system, event_name);
2262
2263 if (!ref_field)
2264 hist_err(tr, HIST_ERR_VAR_NOT_FOUND, errpos(var_name));
2265
2266 return ref_field;
2267 }
2268
2269 static struct ftrace_event_field *
parse_field(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * field_str,unsigned long * flags,unsigned long * buckets)2270 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
2271 char *field_str, unsigned long *flags, unsigned long *buckets)
2272 {
2273 struct ftrace_event_field *field = NULL;
2274 char *field_name, *modifier, *str;
2275 struct trace_array *tr = file->tr;
2276
2277 modifier = str = kstrdup(field_str, GFP_KERNEL);
2278 if (!modifier)
2279 return ERR_PTR(-ENOMEM);
2280
2281 field_name = strsep(&modifier, ".");
2282 if (modifier) {
2283 if (strcmp(modifier, "hex") == 0)
2284 *flags |= HIST_FIELD_FL_HEX;
2285 else if (strcmp(modifier, "sym") == 0)
2286 *flags |= HIST_FIELD_FL_SYM;
2287 /*
2288 * 'sym-offset' occurrences in the trigger string are modified
2289 * to 'symXoffset' to simplify arithmetic expression parsing.
2290 */
2291 else if (strcmp(modifier, "symXoffset") == 0)
2292 *flags |= HIST_FIELD_FL_SYM_OFFSET;
2293 else if ((strcmp(modifier, "execname") == 0) &&
2294 (strcmp(field_name, "common_pid") == 0))
2295 *flags |= HIST_FIELD_FL_EXECNAME;
2296 else if (strcmp(modifier, "syscall") == 0)
2297 *flags |= HIST_FIELD_FL_SYSCALL;
2298 else if (strcmp(modifier, "log2") == 0)
2299 *flags |= HIST_FIELD_FL_LOG2;
2300 else if (strcmp(modifier, "usecs") == 0)
2301 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS;
2302 else if (strncmp(modifier, "bucket", 6) == 0) {
2303 int ret;
2304
2305 modifier += 6;
2306
2307 if (*modifier == 's')
2308 modifier++;
2309 if (*modifier != '=')
2310 goto error;
2311 modifier++;
2312 ret = kstrtoul(modifier, 0, buckets);
2313 if (ret || !(*buckets))
2314 goto error;
2315 *flags |= HIST_FIELD_FL_BUCKET;
2316 } else {
2317 error:
2318 hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier));
2319 field = ERR_PTR(-EINVAL);
2320 goto out;
2321 }
2322 }
2323
2324 if (strcmp(field_name, "common_timestamp") == 0) {
2325 *flags |= HIST_FIELD_FL_TIMESTAMP;
2326 hist_data->enable_timestamps = true;
2327 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS)
2328 hist_data->attrs->ts_in_usecs = true;
2329 } else if (strcmp(field_name, "common_cpu") == 0)
2330 *flags |= HIST_FIELD_FL_CPU;
2331 else {
2332 field = trace_find_event_field(file->event_call, field_name);
2333 if (!field || !field->size) {
2334 /*
2335 * For backward compatibility, if field_name
2336 * was "cpu", then we treat this the same as
2337 * common_cpu. This also works for "CPU".
2338 */
2339 if (field && field->filter_type == FILTER_CPU) {
2340 *flags |= HIST_FIELD_FL_CPU;
2341 } else {
2342 hist_err(tr, HIST_ERR_FIELD_NOT_FOUND,
2343 errpos(field_name));
2344 field = ERR_PTR(-EINVAL);
2345 goto out;
2346 }
2347 }
2348 }
2349 out:
2350 kfree(str);
2351
2352 return field;
2353 }
2354
create_alias(struct hist_trigger_data * hist_data,struct hist_field * var_ref,char * var_name)2355 static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
2356 struct hist_field *var_ref,
2357 char *var_name)
2358 {
2359 struct hist_field *alias = NULL;
2360 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR;
2361
2362 alias = create_hist_field(hist_data, NULL, flags, var_name);
2363 if (!alias)
2364 return NULL;
2365
2366 alias->fn_num = var_ref->fn_num;
2367 alias->operands[0] = var_ref;
2368
2369 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) {
2370 destroy_hist_field(alias, 0);
2371 return NULL;
2372 }
2373
2374 alias->var_ref_idx = var_ref->var_ref_idx;
2375
2376 return alias;
2377 }
2378
parse_const(struct hist_trigger_data * hist_data,char * str,char * var_name,unsigned long * flags)2379 static struct hist_field *parse_const(struct hist_trigger_data *hist_data,
2380 char *str, char *var_name,
2381 unsigned long *flags)
2382 {
2383 struct trace_array *tr = hist_data->event_file->tr;
2384 struct hist_field *field = NULL;
2385 u64 constant;
2386
2387 if (kstrtoull(str, 0, &constant)) {
2388 hist_err(tr, HIST_ERR_EXPECT_NUMBER, errpos(str));
2389 return NULL;
2390 }
2391
2392 *flags |= HIST_FIELD_FL_CONST;
2393 field = create_hist_field(hist_data, NULL, *flags, var_name);
2394 if (!field)
2395 return NULL;
2396
2397 field->constant = constant;
2398
2399 return field;
2400 }
2401
parse_atom(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long * flags,char * var_name)2402 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
2403 struct trace_event_file *file, char *str,
2404 unsigned long *flags, char *var_name)
2405 {
2406 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
2407 struct ftrace_event_field *field = NULL;
2408 struct hist_field *hist_field = NULL;
2409 unsigned long buckets = 0;
2410 int ret = 0;
2411
2412 if (isdigit(str[0])) {
2413 hist_field = parse_const(hist_data, str, var_name, flags);
2414 if (!hist_field) {
2415 ret = -EINVAL;
2416 goto out;
2417 }
2418 return hist_field;
2419 }
2420
2421 s = strchr(str, '.');
2422 if (s) {
2423 s = strchr(++s, '.');
2424 if (s) {
2425 ref_system = strsep(&str, ".");
2426 if (!str) {
2427 ret = -EINVAL;
2428 goto out;
2429 }
2430 ref_event = strsep(&str, ".");
2431 if (!str) {
2432 ret = -EINVAL;
2433 goto out;
2434 }
2435 ref_var = str;
2436 }
2437 }
2438
2439 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var);
2440 if (!s) {
2441 hist_field = parse_var_ref(hist_data, ref_system,
2442 ref_event, ref_var);
2443 if (hist_field) {
2444 if (var_name) {
2445 hist_field = create_alias(hist_data, hist_field, var_name);
2446 if (!hist_field) {
2447 ret = -ENOMEM;
2448 goto out;
2449 }
2450 }
2451 return hist_field;
2452 }
2453 } else
2454 str = s;
2455
2456 field = parse_field(hist_data, file, str, flags, &buckets);
2457 if (IS_ERR(field)) {
2458 ret = PTR_ERR(field);
2459 goto out;
2460 }
2461
2462 hist_field = create_hist_field(hist_data, field, *flags, var_name);
2463 if (!hist_field) {
2464 ret = -ENOMEM;
2465 goto out;
2466 }
2467 hist_field->buckets = buckets;
2468
2469 return hist_field;
2470 out:
2471 return ERR_PTR(ret);
2472 }
2473
2474 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2475 struct trace_event_file *file,
2476 char *str, unsigned long flags,
2477 char *var_name, unsigned int *n_subexprs);
2478
parse_unary(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long flags,char * var_name,unsigned int * n_subexprs)2479 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
2480 struct trace_event_file *file,
2481 char *str, unsigned long flags,
2482 char *var_name, unsigned int *n_subexprs)
2483 {
2484 struct hist_field *operand1, *expr = NULL;
2485 unsigned long operand_flags;
2486 int ret = 0;
2487 char *s;
2488
2489 /* Unary minus operator, increment n_subexprs */
2490 ++*n_subexprs;
2491
2492 /* we support only -(xxx) i.e. explicit parens required */
2493
2494 if (*n_subexprs > 3) {
2495 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str));
2496 ret = -EINVAL;
2497 goto free;
2498 }
2499
2500 str++; /* skip leading '-' */
2501
2502 s = strchr(str, '(');
2503 if (s)
2504 str++;
2505 else {
2506 ret = -EINVAL;
2507 goto free;
2508 }
2509
2510 s = strrchr(str, ')');
2511 if (s) {
2512 /* unary minus not supported in sub-expressions */
2513 if (*(s+1) != '\0') {
2514 hist_err(file->tr, HIST_ERR_UNARY_MINUS_SUBEXPR,
2515 errpos(str));
2516 ret = -EINVAL;
2517 goto free;
2518 }
2519 *s = '\0';
2520 }
2521 else {
2522 ret = -EINVAL; /* no closing ')' */
2523 goto free;
2524 }
2525
2526 flags |= HIST_FIELD_FL_EXPR;
2527 expr = create_hist_field(hist_data, NULL, flags, var_name);
2528 if (!expr) {
2529 ret = -ENOMEM;
2530 goto free;
2531 }
2532
2533 operand_flags = 0;
2534 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs);
2535 if (IS_ERR(operand1)) {
2536 ret = PTR_ERR(operand1);
2537 goto free;
2538 }
2539 if (operand1->flags & HIST_FIELD_FL_STRING) {
2540 /* String type can not be the operand of unary operator. */
2541 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
2542 destroy_hist_field(operand1, 0);
2543 ret = -EINVAL;
2544 goto free;
2545 }
2546
2547 expr->flags |= operand1->flags &
2548 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2549 expr->fn_num = HIST_FIELD_FN_UMINUS;
2550 expr->operands[0] = operand1;
2551 expr->size = operand1->size;
2552 expr->is_signed = operand1->is_signed;
2553 expr->operator = FIELD_OP_UNARY_MINUS;
2554 expr->name = expr_str(expr, 0);
2555 expr->type = kstrdup_const(operand1->type, GFP_KERNEL);
2556 if (!expr->type) {
2557 ret = -ENOMEM;
2558 goto free;
2559 }
2560
2561 return expr;
2562 free:
2563 destroy_hist_field(expr, 0);
2564 return ERR_PTR(ret);
2565 }
2566
2567 /*
2568 * If the operands are var refs, return pointers the
2569 * variable(s) referenced in var1 and var2, else NULL.
2570 */
check_expr_operands(struct trace_array * tr,struct hist_field * operand1,struct hist_field * operand2,struct hist_field ** var1,struct hist_field ** var2)2571 static int check_expr_operands(struct trace_array *tr,
2572 struct hist_field *operand1,
2573 struct hist_field *operand2,
2574 struct hist_field **var1,
2575 struct hist_field **var2)
2576 {
2577 unsigned long operand1_flags = operand1->flags;
2578 unsigned long operand2_flags = operand2->flags;
2579
2580 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) ||
2581 (operand1_flags & HIST_FIELD_FL_ALIAS)) {
2582 struct hist_field *var;
2583
2584 var = find_var_field(operand1->var.hist_data, operand1->name);
2585 if (!var)
2586 return -EINVAL;
2587 operand1_flags = var->flags;
2588 *var1 = var;
2589 }
2590
2591 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) ||
2592 (operand2_flags & HIST_FIELD_FL_ALIAS)) {
2593 struct hist_field *var;
2594
2595 var = find_var_field(operand2->var.hist_data, operand2->name);
2596 if (!var)
2597 return -EINVAL;
2598 operand2_flags = var->flags;
2599 *var2 = var;
2600 }
2601
2602 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) !=
2603 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) {
2604 hist_err(tr, HIST_ERR_TIMESTAMP_MISMATCH, 0);
2605 return -EINVAL;
2606 }
2607
2608 return 0;
2609 }
2610
parse_expr(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long flags,char * var_name,unsigned int * n_subexprs)2611 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2612 struct trace_event_file *file,
2613 char *str, unsigned long flags,
2614 char *var_name, unsigned int *n_subexprs)
2615 {
2616 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL;
2617 struct hist_field *var1 = NULL, *var2 = NULL;
2618 unsigned long operand_flags, operand2_flags;
2619 int field_op, ret = -EINVAL;
2620 char *sep, *operand1_str;
2621 enum hist_field_fn op_fn;
2622 bool combine_consts;
2623
2624 if (*n_subexprs > 3) {
2625 hist_err(file->tr, HIST_ERR_TOO_MANY_SUBEXPR, errpos(str));
2626 return ERR_PTR(-EINVAL);
2627 }
2628
2629 field_op = contains_operator(str, &sep);
2630
2631 if (field_op == FIELD_OP_NONE)
2632 return parse_atom(hist_data, file, str, &flags, var_name);
2633
2634 if (field_op == FIELD_OP_UNARY_MINUS)
2635 return parse_unary(hist_data, file, str, flags, var_name, n_subexprs);
2636
2637 /* Binary operator found, increment n_subexprs */
2638 ++*n_subexprs;
2639
2640 /* Split the expression string at the root operator */
2641 if (!sep)
2642 return ERR_PTR(-EINVAL);
2643
2644 *sep = '\0';
2645 operand1_str = str;
2646 str = sep+1;
2647
2648 /* Binary operator requires both operands */
2649 if (*operand1_str == '\0' || *str == '\0')
2650 return ERR_PTR(-EINVAL);
2651
2652 operand_flags = 0;
2653
2654 /* LHS of string is an expression e.g. a+b in a+b+c */
2655 operand1 = parse_expr(hist_data, file, operand1_str, operand_flags, NULL, n_subexprs);
2656 if (IS_ERR(operand1))
2657 return ERR_CAST(operand1);
2658
2659 if (operand1->flags & HIST_FIELD_FL_STRING) {
2660 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(operand1_str));
2661 ret = -EINVAL;
2662 goto free_op1;
2663 }
2664
2665 /* RHS of string is another expression e.g. c in a+b+c */
2666 operand_flags = 0;
2667 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, n_subexprs);
2668 if (IS_ERR(operand2)) {
2669 ret = PTR_ERR(operand2);
2670 goto free_op1;
2671 }
2672 if (operand2->flags & HIST_FIELD_FL_STRING) {
2673 hist_err(file->tr, HIST_ERR_INVALID_STR_OPERAND, errpos(str));
2674 ret = -EINVAL;
2675 goto free_operands;
2676 }
2677
2678 switch (field_op) {
2679 case FIELD_OP_MINUS:
2680 op_fn = HIST_FIELD_FN_MINUS;
2681 break;
2682 case FIELD_OP_PLUS:
2683 op_fn = HIST_FIELD_FN_PLUS;
2684 break;
2685 case FIELD_OP_DIV:
2686 op_fn = HIST_FIELD_FN_DIV;
2687 break;
2688 case FIELD_OP_MULT:
2689 op_fn = HIST_FIELD_FN_MULT;
2690 break;
2691 default:
2692 ret = -EINVAL;
2693 goto free_operands;
2694 }
2695
2696 ret = check_expr_operands(file->tr, operand1, operand2, &var1, &var2);
2697 if (ret)
2698 goto free_operands;
2699
2700 operand_flags = var1 ? var1->flags : operand1->flags;
2701 operand2_flags = var2 ? var2->flags : operand2->flags;
2702
2703 /*
2704 * If both operands are constant, the expression can be
2705 * collapsed to a single constant.
2706 */
2707 combine_consts = operand_flags & operand2_flags & HIST_FIELD_FL_CONST;
2708
2709 flags |= combine_consts ? HIST_FIELD_FL_CONST : HIST_FIELD_FL_EXPR;
2710
2711 flags |= operand1->flags &
2712 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2713
2714 expr = create_hist_field(hist_data, NULL, flags, var_name);
2715 if (!expr) {
2716 ret = -ENOMEM;
2717 goto free_operands;
2718 }
2719
2720 operand1->read_once = true;
2721 operand2->read_once = true;
2722
2723 /* The operands are now owned and free'd by 'expr' */
2724 expr->operands[0] = operand1;
2725 expr->operands[1] = operand2;
2726
2727 if (field_op == FIELD_OP_DIV &&
2728 operand2_flags & HIST_FIELD_FL_CONST) {
2729 u64 divisor = var2 ? var2->constant : operand2->constant;
2730
2731 if (!divisor) {
2732 hist_err(file->tr, HIST_ERR_DIVISION_BY_ZERO, errpos(str));
2733 ret = -EDOM;
2734 goto free_expr;
2735 }
2736
2737 /*
2738 * Copy the divisor here so we don't have to look it up
2739 * later if this is a var ref
2740 */
2741 operand2->constant = divisor;
2742 op_fn = hist_field_get_div_fn(operand2);
2743 }
2744
2745 expr->fn_num = op_fn;
2746
2747 if (combine_consts) {
2748 if (var1)
2749 expr->operands[0] = var1;
2750 if (var2)
2751 expr->operands[1] = var2;
2752
2753 expr->constant = hist_fn_call(expr, NULL, NULL, NULL, NULL);
2754 expr->fn_num = HIST_FIELD_FN_CONST;
2755
2756 expr->operands[0] = NULL;
2757 expr->operands[1] = NULL;
2758
2759 /*
2760 * var refs won't be destroyed immediately
2761 * See: destroy_hist_field()
2762 */
2763 destroy_hist_field(operand2, 0);
2764 destroy_hist_field(operand1, 0);
2765
2766 expr->name = expr_str(expr, 0);
2767 } else {
2768 /* The operand sizes should be the same, so just pick one */
2769 expr->size = operand1->size;
2770 expr->is_signed = operand1->is_signed;
2771
2772 expr->operator = field_op;
2773 expr->type = kstrdup_const(operand1->type, GFP_KERNEL);
2774 if (!expr->type) {
2775 ret = -ENOMEM;
2776 goto free_expr;
2777 }
2778
2779 expr->name = expr_str(expr, 0);
2780 }
2781
2782 return expr;
2783
2784 free_operands:
2785 destroy_hist_field(operand2, 0);
2786 free_op1:
2787 destroy_hist_field(operand1, 0);
2788 return ERR_PTR(ret);
2789
2790 free_expr:
2791 destroy_hist_field(expr, 0);
2792 return ERR_PTR(ret);
2793 }
2794
find_trigger_filter(struct hist_trigger_data * hist_data,struct trace_event_file * file)2795 static char *find_trigger_filter(struct hist_trigger_data *hist_data,
2796 struct trace_event_file *file)
2797 {
2798 struct event_trigger_data *test;
2799
2800 lockdep_assert_held(&event_mutex);
2801
2802 list_for_each_entry(test, &file->triggers, list) {
2803 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2804 if (test->private_data == hist_data)
2805 return test->filter_str;
2806 }
2807 }
2808
2809 return NULL;
2810 }
2811
2812 static struct event_command trigger_hist_cmd;
2813 static int event_hist_trigger_parse(struct event_command *cmd_ops,
2814 struct trace_event_file *file,
2815 char *glob, char *cmd,
2816 char *param_and_filter);
2817
compatible_keys(struct hist_trigger_data * target_hist_data,struct hist_trigger_data * hist_data,unsigned int n_keys)2818 static bool compatible_keys(struct hist_trigger_data *target_hist_data,
2819 struct hist_trigger_data *hist_data,
2820 unsigned int n_keys)
2821 {
2822 struct hist_field *target_hist_field, *hist_field;
2823 unsigned int n, i, j;
2824
2825 if (hist_data->n_fields - hist_data->n_vals != n_keys)
2826 return false;
2827
2828 i = hist_data->n_vals;
2829 j = target_hist_data->n_vals;
2830
2831 for (n = 0; n < n_keys; n++) {
2832 hist_field = hist_data->fields[i + n];
2833 target_hist_field = target_hist_data->fields[j + n];
2834
2835 if (strcmp(hist_field->type, target_hist_field->type) != 0)
2836 return false;
2837 if (hist_field->size != target_hist_field->size)
2838 return false;
2839 if (hist_field->is_signed != target_hist_field->is_signed)
2840 return false;
2841 }
2842
2843 return true;
2844 }
2845
2846 static struct hist_trigger_data *
find_compatible_hist(struct hist_trigger_data * target_hist_data,struct trace_event_file * file)2847 find_compatible_hist(struct hist_trigger_data *target_hist_data,
2848 struct trace_event_file *file)
2849 {
2850 struct hist_trigger_data *hist_data;
2851 struct event_trigger_data *test;
2852 unsigned int n_keys;
2853
2854 lockdep_assert_held(&event_mutex);
2855
2856 n_keys = target_hist_data->n_fields - target_hist_data->n_vals;
2857
2858 list_for_each_entry(test, &file->triggers, list) {
2859 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2860 hist_data = test->private_data;
2861
2862 if (compatible_keys(target_hist_data, hist_data, n_keys))
2863 return hist_data;
2864 }
2865 }
2866
2867 return NULL;
2868 }
2869
event_file(struct trace_array * tr,char * system,char * event_name)2870 static struct trace_event_file *event_file(struct trace_array *tr,
2871 char *system, char *event_name)
2872 {
2873 struct trace_event_file *file;
2874
2875 file = __find_event_file(tr, system, event_name);
2876 if (!file)
2877 return ERR_PTR(-EINVAL);
2878
2879 return file;
2880 }
2881
2882 static struct hist_field *
find_synthetic_field_var(struct hist_trigger_data * target_hist_data,char * system,char * event_name,char * field_name)2883 find_synthetic_field_var(struct hist_trigger_data *target_hist_data,
2884 char *system, char *event_name, char *field_name)
2885 {
2886 struct hist_field *event_var;
2887 char *synthetic_name;
2888
2889 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2890 if (!synthetic_name)
2891 return ERR_PTR(-ENOMEM);
2892
2893 strcpy(synthetic_name, "synthetic_");
2894 strcat(synthetic_name, field_name);
2895
2896 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name);
2897
2898 kfree(synthetic_name);
2899
2900 return event_var;
2901 }
2902
2903 /**
2904 * create_field_var_hist - Automatically create a histogram and var for a field
2905 * @target_hist_data: The target hist trigger
2906 * @subsys_name: Optional subsystem name
2907 * @event_name: Optional event name
2908 * @field_name: The name of the field (and the resulting variable)
2909 *
2910 * Hist trigger actions fetch data from variables, not directly from
2911 * events. However, for convenience, users are allowed to directly
2912 * specify an event field in an action, which will be automatically
2913 * converted into a variable on their behalf.
2914 *
2915 * If a user specifies a field on an event that isn't the event the
2916 * histogram currently being defined (the target event histogram), the
2917 * only way that can be accomplished is if a new hist trigger is
2918 * created and the field variable defined on that.
2919 *
2920 * This function creates a new histogram compatible with the target
2921 * event (meaning a histogram with the same key as the target
2922 * histogram), and creates a variable for the specified field, but
2923 * with 'synthetic_' prepended to the variable name in order to avoid
2924 * collision with normal field variables.
2925 *
2926 * Return: The variable created for the field.
2927 */
2928 static struct hist_field *
create_field_var_hist(struct hist_trigger_data * target_hist_data,char * subsys_name,char * event_name,char * field_name)2929 create_field_var_hist(struct hist_trigger_data *target_hist_data,
2930 char *subsys_name, char *event_name, char *field_name)
2931 {
2932 struct trace_array *tr = target_hist_data->event_file->tr;
2933 struct hist_trigger_data *hist_data;
2934 unsigned int i, n, first = true;
2935 struct field_var_hist *var_hist;
2936 struct trace_event_file *file;
2937 struct hist_field *key_field;
2938 struct hist_field *event_var;
2939 char *saved_filter;
2940 char *cmd;
2941 int ret;
2942
2943 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) {
2944 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name));
2945 return ERR_PTR(-EINVAL);
2946 }
2947
2948 file = event_file(tr, subsys_name, event_name);
2949
2950 if (IS_ERR(file)) {
2951 hist_err(tr, HIST_ERR_EVENT_FILE_NOT_FOUND, errpos(field_name));
2952 ret = PTR_ERR(file);
2953 return ERR_PTR(ret);
2954 }
2955
2956 /*
2957 * Look for a histogram compatible with target. We'll use the
2958 * found histogram specification to create a new matching
2959 * histogram with our variable on it. target_hist_data is not
2960 * yet a registered histogram so we can't use that.
2961 */
2962 hist_data = find_compatible_hist(target_hist_data, file);
2963 if (!hist_data) {
2964 hist_err(tr, HIST_ERR_HIST_NOT_FOUND, errpos(field_name));
2965 return ERR_PTR(-EINVAL);
2966 }
2967
2968 /* See if a synthetic field variable has already been created */
2969 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
2970 event_name, field_name);
2971 if (!IS_ERR_OR_NULL(event_var))
2972 return event_var;
2973
2974 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL);
2975 if (!var_hist)
2976 return ERR_PTR(-ENOMEM);
2977
2978 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2979 if (!cmd) {
2980 kfree(var_hist);
2981 return ERR_PTR(-ENOMEM);
2982 }
2983
2984 /* Use the same keys as the compatible histogram */
2985 strcat(cmd, "keys=");
2986
2987 for_each_hist_key_field(i, hist_data) {
2988 key_field = hist_data->fields[i];
2989 if (!first)
2990 strcat(cmd, ",");
2991 strcat(cmd, key_field->field->name);
2992 first = false;
2993 }
2994
2995 /* Create the synthetic field variable specification */
2996 strcat(cmd, ":synthetic_");
2997 strcat(cmd, field_name);
2998 strcat(cmd, "=");
2999 strcat(cmd, field_name);
3000
3001 /* Use the same filter as the compatible histogram */
3002 saved_filter = find_trigger_filter(hist_data, file);
3003 if (saved_filter) {
3004 strcat(cmd, " if ");
3005 strcat(cmd, saved_filter);
3006 }
3007
3008 var_hist->cmd = kstrdup(cmd, GFP_KERNEL);
3009 if (!var_hist->cmd) {
3010 kfree(cmd);
3011 kfree(var_hist);
3012 return ERR_PTR(-ENOMEM);
3013 }
3014
3015 /* Save the compatible histogram information */
3016 var_hist->hist_data = hist_data;
3017
3018 /* Create the new histogram with our variable */
3019 ret = event_hist_trigger_parse(&trigger_hist_cmd, file,
3020 "", "hist", cmd);
3021 if (ret) {
3022 kfree(cmd);
3023 kfree(var_hist->cmd);
3024 kfree(var_hist);
3025 hist_err(tr, HIST_ERR_HIST_CREATE_FAIL, errpos(field_name));
3026 return ERR_PTR(ret);
3027 }
3028
3029 kfree(cmd);
3030
3031 /* If we can't find the variable, something went wrong */
3032 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
3033 event_name, field_name);
3034 if (IS_ERR_OR_NULL(event_var)) {
3035 kfree(var_hist->cmd);
3036 kfree(var_hist);
3037 hist_err(tr, HIST_ERR_SYNTH_VAR_NOT_FOUND, errpos(field_name));
3038 return ERR_PTR(-EINVAL);
3039 }
3040
3041 n = target_hist_data->n_field_var_hists;
3042 target_hist_data->field_var_hists[n] = var_hist;
3043 target_hist_data->n_field_var_hists++;
3044
3045 return event_var;
3046 }
3047
3048 static struct hist_field *
find_target_event_var(struct hist_trigger_data * hist_data,char * subsys_name,char * event_name,char * var_name)3049 find_target_event_var(struct hist_trigger_data *hist_data,
3050 char *subsys_name, char *event_name, char *var_name)
3051 {
3052 struct trace_event_file *file = hist_data->event_file;
3053 struct hist_field *hist_field = NULL;
3054
3055 if (subsys_name) {
3056 struct trace_event_call *call;
3057
3058 if (!event_name)
3059 return NULL;
3060
3061 call = file->event_call;
3062
3063 if (strcmp(subsys_name, call->class->system) != 0)
3064 return NULL;
3065
3066 if (strcmp(event_name, trace_event_name(call)) != 0)
3067 return NULL;
3068 }
3069
3070 hist_field = find_var_field(hist_data, var_name);
3071
3072 return hist_field;
3073 }
3074
__update_field_vars(struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * rec,struct field_var ** field_vars,unsigned int n_field_vars,unsigned int field_var_str_start)3075 static inline void __update_field_vars(struct tracing_map_elt *elt,
3076 struct trace_buffer *buffer,
3077 struct ring_buffer_event *rbe,
3078 void *rec,
3079 struct field_var **field_vars,
3080 unsigned int n_field_vars,
3081 unsigned int field_var_str_start)
3082 {
3083 struct hist_elt_data *elt_data = elt->private_data;
3084 unsigned int i, j, var_idx;
3085 u64 var_val;
3086
3087 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) {
3088 struct field_var *field_var = field_vars[i];
3089 struct hist_field *var = field_var->var;
3090 struct hist_field *val = field_var->val;
3091
3092 var_val = hist_fn_call(val, elt, buffer, rbe, rec);
3093 var_idx = var->var.idx;
3094
3095 if (val->flags & HIST_FIELD_FL_STRING) {
3096 char *str = elt_data->field_var_str[j++];
3097 char *val_str = (char *)(uintptr_t)var_val;
3098 unsigned int size;
3099
3100 size = min(val->size, STR_VAR_LEN_MAX);
3101 strscpy(str, val_str, size);
3102 var_val = (u64)(uintptr_t)str;
3103 }
3104 tracing_map_set_var(elt, var_idx, var_val);
3105 }
3106 }
3107
update_field_vars(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * rec)3108 static void update_field_vars(struct hist_trigger_data *hist_data,
3109 struct tracing_map_elt *elt,
3110 struct trace_buffer *buffer,
3111 struct ring_buffer_event *rbe,
3112 void *rec)
3113 {
3114 __update_field_vars(elt, buffer, rbe, rec, hist_data->field_vars,
3115 hist_data->n_field_vars, 0);
3116 }
3117
save_track_data_vars(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct trace_buffer * buffer,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)3118 static void save_track_data_vars(struct hist_trigger_data *hist_data,
3119 struct tracing_map_elt *elt,
3120 struct trace_buffer *buffer, void *rec,
3121 struct ring_buffer_event *rbe, void *key,
3122 struct action_data *data, u64 *var_ref_vals)
3123 {
3124 __update_field_vars(elt, buffer, rbe, rec, hist_data->save_vars,
3125 hist_data->n_save_vars, hist_data->n_field_var_str);
3126 }
3127
create_var(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * name,int size,const char * type)3128 static struct hist_field *create_var(struct hist_trigger_data *hist_data,
3129 struct trace_event_file *file,
3130 char *name, int size, const char *type)
3131 {
3132 struct hist_field *var;
3133 int idx;
3134
3135 if (find_var(hist_data, file, name) && !hist_data->remove) {
3136 var = ERR_PTR(-EINVAL);
3137 goto out;
3138 }
3139
3140 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
3141 if (!var) {
3142 var = ERR_PTR(-ENOMEM);
3143 goto out;
3144 }
3145
3146 idx = tracing_map_add_var(hist_data->map);
3147 if (idx < 0) {
3148 kfree(var);
3149 var = ERR_PTR(-EINVAL);
3150 goto out;
3151 }
3152
3153 var->ref = 1;
3154 var->flags = HIST_FIELD_FL_VAR;
3155 var->var.idx = idx;
3156 var->var.hist_data = var->hist_data = hist_data;
3157 var->size = size;
3158 var->var.name = kstrdup(name, GFP_KERNEL);
3159 var->type = kstrdup_const(type, GFP_KERNEL);
3160 if (!var->var.name || !var->type) {
3161 kfree_const(var->type);
3162 kfree(var->var.name);
3163 kfree(var);
3164 var = ERR_PTR(-ENOMEM);
3165 }
3166 out:
3167 return var;
3168 }
3169
create_field_var(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * field_name)3170 static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
3171 struct trace_event_file *file,
3172 char *field_name)
3173 {
3174 struct hist_field *val = NULL, *var = NULL;
3175 unsigned long flags = HIST_FIELD_FL_VAR;
3176 struct trace_array *tr = file->tr;
3177 struct field_var *field_var;
3178 int ret = 0;
3179
3180 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) {
3181 hist_err(tr, HIST_ERR_TOO_MANY_FIELD_VARS, errpos(field_name));
3182 ret = -EINVAL;
3183 goto err;
3184 }
3185
3186 val = parse_atom(hist_data, file, field_name, &flags, NULL);
3187 if (IS_ERR(val)) {
3188 hist_err(tr, HIST_ERR_FIELD_VAR_PARSE_FAIL, errpos(field_name));
3189 ret = PTR_ERR(val);
3190 goto err;
3191 }
3192
3193 var = create_var(hist_data, file, field_name, val->size, val->type);
3194 if (IS_ERR(var)) {
3195 hist_err(tr, HIST_ERR_VAR_CREATE_FIND_FAIL, errpos(field_name));
3196 kfree(val);
3197 ret = PTR_ERR(var);
3198 goto err;
3199 }
3200
3201 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL);
3202 if (!field_var) {
3203 kfree(val);
3204 kfree(var);
3205 ret = -ENOMEM;
3206 goto err;
3207 }
3208
3209 field_var->var = var;
3210 field_var->val = val;
3211 out:
3212 return field_var;
3213 err:
3214 field_var = ERR_PTR(ret);
3215 goto out;
3216 }
3217
3218 /**
3219 * create_target_field_var - Automatically create a variable for a field
3220 * @target_hist_data: The target hist trigger
3221 * @subsys_name: Optional subsystem name
3222 * @event_name: Optional event name
3223 * @var_name: The name of the field (and the resulting variable)
3224 *
3225 * Hist trigger actions fetch data from variables, not directly from
3226 * events. However, for convenience, users are allowed to directly
3227 * specify an event field in an action, which will be automatically
3228 * converted into a variable on their behalf.
3229 *
3230 * This function creates a field variable with the name var_name on
3231 * the hist trigger currently being defined on the target event. If
3232 * subsys_name and event_name are specified, this function simply
3233 * verifies that they do in fact match the target event subsystem and
3234 * event name.
3235 *
3236 * Return: The variable created for the field.
3237 */
3238 static struct field_var *
create_target_field_var(struct hist_trigger_data * target_hist_data,char * subsys_name,char * event_name,char * var_name)3239 create_target_field_var(struct hist_trigger_data *target_hist_data,
3240 char *subsys_name, char *event_name, char *var_name)
3241 {
3242 struct trace_event_file *file = target_hist_data->event_file;
3243
3244 if (subsys_name) {
3245 struct trace_event_call *call;
3246
3247 if (!event_name)
3248 return NULL;
3249
3250 call = file->event_call;
3251
3252 if (strcmp(subsys_name, call->class->system) != 0)
3253 return NULL;
3254
3255 if (strcmp(event_name, trace_event_name(call)) != 0)
3256 return NULL;
3257 }
3258
3259 return create_field_var(target_hist_data, file, var_name);
3260 }
3261
check_track_val_max(u64 track_val,u64 var_val)3262 static bool check_track_val_max(u64 track_val, u64 var_val)
3263 {
3264 if (var_val <= track_val)
3265 return false;
3266
3267 return true;
3268 }
3269
check_track_val_changed(u64 track_val,u64 var_val)3270 static bool check_track_val_changed(u64 track_val, u64 var_val)
3271 {
3272 if (var_val == track_val)
3273 return false;
3274
3275 return true;
3276 }
3277
get_track_val(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct action_data * data)3278 static u64 get_track_val(struct hist_trigger_data *hist_data,
3279 struct tracing_map_elt *elt,
3280 struct action_data *data)
3281 {
3282 unsigned int track_var_idx = data->track_data.track_var->var.idx;
3283 u64 track_val;
3284
3285 track_val = tracing_map_read_var(elt, track_var_idx);
3286
3287 return track_val;
3288 }
3289
save_track_val(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct action_data * data,u64 var_val)3290 static void save_track_val(struct hist_trigger_data *hist_data,
3291 struct tracing_map_elt *elt,
3292 struct action_data *data, u64 var_val)
3293 {
3294 unsigned int track_var_idx = data->track_data.track_var->var.idx;
3295
3296 tracing_map_set_var(elt, track_var_idx, var_val);
3297 }
3298
save_track_data(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct trace_buffer * buffer,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)3299 static void save_track_data(struct hist_trigger_data *hist_data,
3300 struct tracing_map_elt *elt,
3301 struct trace_buffer *buffer, void *rec,
3302 struct ring_buffer_event *rbe, void *key,
3303 struct action_data *data, u64 *var_ref_vals)
3304 {
3305 if (data->track_data.save_data)
3306 data->track_data.save_data(hist_data, elt, buffer, rec, rbe,
3307 key, data, var_ref_vals);
3308 }
3309
check_track_val(struct tracing_map_elt * elt,struct action_data * data,u64 var_val)3310 static bool check_track_val(struct tracing_map_elt *elt,
3311 struct action_data *data,
3312 u64 var_val)
3313 {
3314 struct hist_trigger_data *hist_data;
3315 u64 track_val;
3316
3317 hist_data = data->track_data.track_var->hist_data;
3318 track_val = get_track_val(hist_data, elt, data);
3319
3320 return data->track_data.check_val(track_val, var_val);
3321 }
3322
3323 #ifdef CONFIG_TRACER_SNAPSHOT
cond_snapshot_update(struct trace_array * tr,void * cond_data)3324 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
3325 {
3326 /* called with tr->max_lock held */
3327 struct track_data *track_data = tr->cond_snapshot->cond_data;
3328 struct hist_elt_data *elt_data, *track_elt_data;
3329 struct snapshot_context *context = cond_data;
3330 struct action_data *action;
3331 u64 track_val;
3332
3333 if (!track_data)
3334 return false;
3335
3336 action = track_data->action_data;
3337
3338 track_val = get_track_val(track_data->hist_data, context->elt,
3339 track_data->action_data);
3340
3341 if (!action->track_data.check_val(track_data->track_val, track_val))
3342 return false;
3343
3344 track_data->track_val = track_val;
3345 memcpy(track_data->key, context->key, track_data->key_len);
3346
3347 elt_data = context->elt->private_data;
3348 track_elt_data = track_data->elt.private_data;
3349 if (elt_data->comm)
3350 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN);
3351
3352 track_data->updated = true;
3353
3354 return true;
3355 }
3356
save_track_data_snapshot(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct trace_buffer * buffer,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)3357 static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
3358 struct tracing_map_elt *elt,
3359 struct trace_buffer *buffer, void *rec,
3360 struct ring_buffer_event *rbe, void *key,
3361 struct action_data *data,
3362 u64 *var_ref_vals)
3363 {
3364 struct trace_event_file *file = hist_data->event_file;
3365 struct snapshot_context context;
3366
3367 context.elt = elt;
3368 context.key = key;
3369
3370 tracing_snapshot_cond(file->tr, &context);
3371 }
3372
3373 static void hist_trigger_print_key(struct seq_file *m,
3374 struct hist_trigger_data *hist_data,
3375 void *key,
3376 struct tracing_map_elt *elt);
3377
snapshot_action(struct hist_trigger_data * hist_data)3378 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data)
3379 {
3380 unsigned int i;
3381
3382 if (!hist_data->n_actions)
3383 return NULL;
3384
3385 for (i = 0; i < hist_data->n_actions; i++) {
3386 struct action_data *data = hist_data->actions[i];
3387
3388 if (data->action == ACTION_SNAPSHOT)
3389 return data;
3390 }
3391
3392 return NULL;
3393 }
3394
track_data_snapshot_print(struct seq_file * m,struct hist_trigger_data * hist_data)3395 static void track_data_snapshot_print(struct seq_file *m,
3396 struct hist_trigger_data *hist_data)
3397 {
3398 struct trace_event_file *file = hist_data->event_file;
3399 struct track_data *track_data;
3400 struct action_data *action;
3401
3402 track_data = tracing_cond_snapshot_data(file->tr);
3403 if (!track_data)
3404 return;
3405
3406 if (!track_data->updated)
3407 return;
3408
3409 action = snapshot_action(hist_data);
3410 if (!action)
3411 return;
3412
3413 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n");
3414 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu",
3415 action->handler == HANDLER_ONMAX ? "onmax" : "onchange",
3416 action->track_data.var_str, track_data->track_val);
3417
3418 seq_puts(m, "\ttriggered by event with key: ");
3419 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt);
3420 seq_putc(m, '\n');
3421 }
3422 #else
cond_snapshot_update(struct trace_array * tr,void * cond_data)3423 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data)
3424 {
3425 return false;
3426 }
save_track_data_snapshot(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct trace_buffer * buffer,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)3427 static void save_track_data_snapshot(struct hist_trigger_data *hist_data,
3428 struct tracing_map_elt *elt,
3429 struct trace_buffer *buffer, void *rec,
3430 struct ring_buffer_event *rbe, void *key,
3431 struct action_data *data,
3432 u64 *var_ref_vals) {}
track_data_snapshot_print(struct seq_file * m,struct hist_trigger_data * hist_data)3433 static void track_data_snapshot_print(struct seq_file *m,
3434 struct hist_trigger_data *hist_data) {}
3435 #endif /* CONFIG_TRACER_SNAPSHOT */
3436
track_data_print(struct seq_file * m,struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct action_data * data)3437 static void track_data_print(struct seq_file *m,
3438 struct hist_trigger_data *hist_data,
3439 struct tracing_map_elt *elt,
3440 struct action_data *data)
3441 {
3442 u64 track_val = get_track_val(hist_data, elt, data);
3443 unsigned int i, save_var_idx;
3444
3445 if (data->handler == HANDLER_ONMAX)
3446 seq_printf(m, "\n\tmax: %10llu", track_val);
3447 else if (data->handler == HANDLER_ONCHANGE)
3448 seq_printf(m, "\n\tchanged: %10llu", track_val);
3449
3450 if (data->action == ACTION_SNAPSHOT)
3451 return;
3452
3453 for (i = 0; i < hist_data->n_save_vars; i++) {
3454 struct hist_field *save_val = hist_data->save_vars[i]->val;
3455 struct hist_field *save_var = hist_data->save_vars[i]->var;
3456 u64 val;
3457
3458 save_var_idx = save_var->var.idx;
3459
3460 val = tracing_map_read_var(elt, save_var_idx);
3461
3462 if (save_val->flags & HIST_FIELD_FL_STRING) {
3463 seq_printf(m, " %s: %-32s", save_var->var.name,
3464 (char *)(uintptr_t)(val));
3465 } else
3466 seq_printf(m, " %s: %10llu", save_var->var.name, val);
3467 }
3468 }
3469
ontrack_action(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct trace_buffer * buffer,void * rec,struct ring_buffer_event * rbe,void * key,struct action_data * data,u64 * var_ref_vals)3470 static void ontrack_action(struct hist_trigger_data *hist_data,
3471 struct tracing_map_elt *elt,
3472 struct trace_buffer *buffer, void *rec,
3473 struct ring_buffer_event *rbe, void *key,
3474 struct action_data *data, u64 *var_ref_vals)
3475 {
3476 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx];
3477
3478 if (check_track_val(elt, data, var_val)) {
3479 save_track_val(hist_data, elt, data, var_val);
3480 save_track_data(hist_data, elt, buffer, rec, rbe,
3481 key, data, var_ref_vals);
3482 }
3483 }
3484
action_data_destroy(struct action_data * data)3485 static void action_data_destroy(struct action_data *data)
3486 {
3487 unsigned int i;
3488
3489 lockdep_assert_held(&event_mutex);
3490
3491 kfree(data->action_name);
3492
3493 for (i = 0; i < data->n_params; i++)
3494 kfree(data->params[i]);
3495
3496 if (data->synth_event)
3497 data->synth_event->ref--;
3498
3499 kfree(data->synth_event_name);
3500
3501 kfree(data);
3502 }
3503
track_data_destroy(struct hist_trigger_data * hist_data,struct action_data * data)3504 static void track_data_destroy(struct hist_trigger_data *hist_data,
3505 struct action_data *data)
3506 {
3507 struct trace_event_file *file = hist_data->event_file;
3508
3509 destroy_hist_field(data->track_data.track_var, 0);
3510
3511 if (data->action == ACTION_SNAPSHOT) {
3512 struct track_data *track_data;
3513
3514 track_data = tracing_cond_snapshot_data(file->tr);
3515 if (track_data && track_data->hist_data == hist_data) {
3516 tracing_snapshot_cond_disable(file->tr);
3517 track_data_free(track_data);
3518 }
3519 }
3520
3521 kfree(data->track_data.var_str);
3522
3523 action_data_destroy(data);
3524 }
3525
3526 static int action_create(struct hist_trigger_data *hist_data,
3527 struct action_data *data);
3528
track_data_create(struct hist_trigger_data * hist_data,struct action_data * data)3529 static int track_data_create(struct hist_trigger_data *hist_data,
3530 struct action_data *data)
3531 {
3532 struct hist_field *var_field, *ref_field, *track_var = NULL;
3533 struct trace_event_file *file = hist_data->event_file;
3534 struct trace_array *tr = file->tr;
3535 char *track_data_var_str;
3536 int ret = 0;
3537
3538 track_data_var_str = data->track_data.var_str;
3539 if (track_data_var_str[0] != '$') {
3540 hist_err(tr, HIST_ERR_ONX_NOT_VAR, errpos(track_data_var_str));
3541 return -EINVAL;
3542 }
3543 track_data_var_str++;
3544
3545 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str);
3546 if (!var_field) {
3547 hist_err(tr, HIST_ERR_ONX_VAR_NOT_FOUND, errpos(track_data_var_str));
3548 return -EINVAL;
3549 }
3550
3551 ref_field = create_var_ref(hist_data, var_field, NULL, NULL);
3552 if (!ref_field)
3553 return -ENOMEM;
3554
3555 data->track_data.var_ref = ref_field;
3556
3557 if (data->handler == HANDLER_ONMAX)
3558 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64");
3559 if (IS_ERR(track_var)) {
3560 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0);
3561 ret = PTR_ERR(track_var);
3562 goto out;
3563 }
3564
3565 if (data->handler == HANDLER_ONCHANGE)
3566 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64");
3567 if (IS_ERR(track_var)) {
3568 hist_err(tr, HIST_ERR_ONX_VAR_CREATE_FAIL, 0);
3569 ret = PTR_ERR(track_var);
3570 goto out;
3571 }
3572 data->track_data.track_var = track_var;
3573
3574 ret = action_create(hist_data, data);
3575 out:
3576 return ret;
3577 }
3578
parse_action_params(struct trace_array * tr,char * params,struct action_data * data)3579 static int parse_action_params(struct trace_array *tr, char *params,
3580 struct action_data *data)
3581 {
3582 char *param, *saved_param;
3583 bool first_param = true;
3584 int ret = 0;
3585
3586 while (params) {
3587 if (data->n_params >= SYNTH_FIELDS_MAX) {
3588 hist_err(tr, HIST_ERR_TOO_MANY_PARAMS, 0);
3589 goto out;
3590 }
3591
3592 param = strsep(¶ms, ",");
3593 if (!param) {
3594 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, 0);
3595 ret = -EINVAL;
3596 goto out;
3597 }
3598
3599 param = strstrip(param);
3600 if (strlen(param) < 2) {
3601 hist_err(tr, HIST_ERR_INVALID_PARAM, errpos(param));
3602 ret = -EINVAL;
3603 goto out;
3604 }
3605
3606 saved_param = kstrdup(param, GFP_KERNEL);
3607 if (!saved_param) {
3608 ret = -ENOMEM;
3609 goto out;
3610 }
3611
3612 if (first_param && data->use_trace_keyword) {
3613 data->synth_event_name = saved_param;
3614 first_param = false;
3615 continue;
3616 }
3617 first_param = false;
3618
3619 data->params[data->n_params++] = saved_param;
3620 }
3621 out:
3622 return ret;
3623 }
3624
action_parse(struct trace_array * tr,char * str,struct action_data * data,enum handler_id handler)3625 static int action_parse(struct trace_array *tr, char *str, struct action_data *data,
3626 enum handler_id handler)
3627 {
3628 char *action_name;
3629 int ret = 0;
3630
3631 strsep(&str, ".");
3632 if (!str) {
3633 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0);
3634 ret = -EINVAL;
3635 goto out;
3636 }
3637
3638 action_name = strsep(&str, "(");
3639 if (!action_name || !str) {
3640 hist_err(tr, HIST_ERR_ACTION_NOT_FOUND, 0);
3641 ret = -EINVAL;
3642 goto out;
3643 }
3644
3645 if (str_has_prefix(action_name, "save")) {
3646 char *params = strsep(&str, ")");
3647
3648 if (!params) {
3649 hist_err(tr, HIST_ERR_NO_SAVE_PARAMS, 0);
3650 ret = -EINVAL;
3651 goto out;
3652 }
3653
3654 ret = parse_action_params(tr, params, data);
3655 if (ret)
3656 goto out;
3657
3658 if (handler == HANDLER_ONMAX)
3659 data->track_data.check_val = check_track_val_max;
3660 else if (handler == HANDLER_ONCHANGE)
3661 data->track_data.check_val = check_track_val_changed;
3662 else {
3663 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name));
3664 ret = -EINVAL;
3665 goto out;
3666 }
3667
3668 data->track_data.save_data = save_track_data_vars;
3669 data->fn = ontrack_action;
3670 data->action = ACTION_SAVE;
3671 } else if (str_has_prefix(action_name, "snapshot")) {
3672 char *params = strsep(&str, ")");
3673
3674 if (!str) {
3675 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(params));
3676 ret = -EINVAL;
3677 goto out;
3678 }
3679
3680 if (handler == HANDLER_ONMAX)
3681 data->track_data.check_val = check_track_val_max;
3682 else if (handler == HANDLER_ONCHANGE)
3683 data->track_data.check_val = check_track_val_changed;
3684 else {
3685 hist_err(tr, HIST_ERR_ACTION_MISMATCH, errpos(action_name));
3686 ret = -EINVAL;
3687 goto out;
3688 }
3689
3690 data->track_data.save_data = save_track_data_snapshot;
3691 data->fn = ontrack_action;
3692 data->action = ACTION_SNAPSHOT;
3693 } else {
3694 char *params = strsep(&str, ")");
3695
3696 if (str_has_prefix(action_name, "trace"))
3697 data->use_trace_keyword = true;
3698
3699 if (params) {
3700 ret = parse_action_params(tr, params, data);
3701 if (ret)
3702 goto out;
3703 }
3704
3705 if (handler == HANDLER_ONMAX)
3706 data->track_data.check_val = check_track_val_max;
3707 else if (handler == HANDLER_ONCHANGE)
3708 data->track_data.check_val = check_track_val_changed;
3709
3710 if (handler != HANDLER_ONMATCH) {
3711 data->track_data.save_data = action_trace;
3712 data->fn = ontrack_action;
3713 } else
3714 data->fn = action_trace;
3715
3716 data->action = ACTION_TRACE;
3717 }
3718
3719 data->action_name = kstrdup(action_name, GFP_KERNEL);
3720 if (!data->action_name) {
3721 ret = -ENOMEM;
3722 goto out;
3723 }
3724
3725 data->handler = handler;
3726 out:
3727 return ret;
3728 }
3729
track_data_parse(struct hist_trigger_data * hist_data,char * str,enum handler_id handler)3730 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data,
3731 char *str, enum handler_id handler)
3732 {
3733 struct action_data *data;
3734 int ret = -EINVAL;
3735 char *var_str;
3736
3737 data = kzalloc(sizeof(*data), GFP_KERNEL);
3738 if (!data)
3739 return ERR_PTR(-ENOMEM);
3740
3741 var_str = strsep(&str, ")");
3742 if (!var_str || !str) {
3743 ret = -EINVAL;
3744 goto free;
3745 }
3746
3747 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL);
3748 if (!data->track_data.var_str) {
3749 ret = -ENOMEM;
3750 goto free;
3751 }
3752
3753 ret = action_parse(hist_data->event_file->tr, str, data, handler);
3754 if (ret)
3755 goto free;
3756 out:
3757 return data;
3758 free:
3759 track_data_destroy(hist_data, data);
3760 data = ERR_PTR(ret);
3761 goto out;
3762 }
3763
onmatch_destroy(struct action_data * data)3764 static void onmatch_destroy(struct action_data *data)
3765 {
3766 kfree(data->match_data.event);
3767 kfree(data->match_data.event_system);
3768
3769 action_data_destroy(data);
3770 }
3771
destroy_field_var(struct field_var * field_var)3772 static void destroy_field_var(struct field_var *field_var)
3773 {
3774 if (!field_var)
3775 return;
3776
3777 destroy_hist_field(field_var->var, 0);
3778 destroy_hist_field(field_var->val, 0);
3779
3780 kfree(field_var);
3781 }
3782
destroy_field_vars(struct hist_trigger_data * hist_data)3783 static void destroy_field_vars(struct hist_trigger_data *hist_data)
3784 {
3785 unsigned int i;
3786
3787 for (i = 0; i < hist_data->n_field_vars; i++)
3788 destroy_field_var(hist_data->field_vars[i]);
3789
3790 for (i = 0; i < hist_data->n_save_vars; i++)
3791 destroy_field_var(hist_data->save_vars[i]);
3792 }
3793
save_field_var(struct hist_trigger_data * hist_data,struct field_var * field_var)3794 static void save_field_var(struct hist_trigger_data *hist_data,
3795 struct field_var *field_var)
3796 {
3797 hist_data->field_vars[hist_data->n_field_vars++] = field_var;
3798
3799 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3800 hist_data->n_field_var_str++;
3801 }
3802
3803
check_synth_field(struct synth_event * event,struct hist_field * hist_field,unsigned int field_pos)3804 static int check_synth_field(struct synth_event *event,
3805 struct hist_field *hist_field,
3806 unsigned int field_pos)
3807 {
3808 struct synth_field *field;
3809
3810 if (field_pos >= event->n_fields)
3811 return -EINVAL;
3812
3813 field = event->fields[field_pos];
3814
3815 /*
3816 * A dynamic string synth field can accept static or
3817 * dynamic. A static string synth field can only accept a
3818 * same-sized static string, which is checked for later.
3819 */
3820 if (strstr(hist_field->type, "char[") && field->is_string
3821 && field->is_dynamic)
3822 return 0;
3823
3824 if (strcmp(field->type, hist_field->type) != 0) {
3825 if (field->size != hist_field->size ||
3826 (!field->is_string && field->is_signed != hist_field->is_signed))
3827 return -EINVAL;
3828 }
3829
3830 return 0;
3831 }
3832
3833 static struct hist_field *
trace_action_find_var(struct hist_trigger_data * hist_data,struct action_data * data,char * system,char * event,char * var)3834 trace_action_find_var(struct hist_trigger_data *hist_data,
3835 struct action_data *data,
3836 char *system, char *event, char *var)
3837 {
3838 struct trace_array *tr = hist_data->event_file->tr;
3839 struct hist_field *hist_field;
3840
3841 var++; /* skip '$' */
3842
3843 hist_field = find_target_event_var(hist_data, system, event, var);
3844 if (!hist_field) {
3845 if (!system && data->handler == HANDLER_ONMATCH) {
3846 system = data->match_data.event_system;
3847 event = data->match_data.event;
3848 }
3849
3850 hist_field = find_event_var(hist_data, system, event, var);
3851 }
3852
3853 if (!hist_field)
3854 hist_err(tr, HIST_ERR_PARAM_NOT_FOUND, errpos(var));
3855
3856 return hist_field;
3857 }
3858
3859 static struct hist_field *
trace_action_create_field_var(struct hist_trigger_data * hist_data,struct action_data * data,char * system,char * event,char * var)3860 trace_action_create_field_var(struct hist_trigger_data *hist_data,
3861 struct action_data *data, char *system,
3862 char *event, char *var)
3863 {
3864 struct hist_field *hist_field = NULL;
3865 struct field_var *field_var;
3866
3867 /*
3868 * First try to create a field var on the target event (the
3869 * currently being defined). This will create a variable for
3870 * unqualified fields on the target event, or if qualified,
3871 * target fields that have qualified names matching the target.
3872 */
3873 field_var = create_target_field_var(hist_data, system, event, var);
3874
3875 if (field_var && !IS_ERR(field_var)) {
3876 save_field_var(hist_data, field_var);
3877 hist_field = field_var->var;
3878 } else {
3879 field_var = NULL;
3880 /*
3881 * If no explicit system.event is specified, default to
3882 * looking for fields on the onmatch(system.event.xxx)
3883 * event.
3884 */
3885 if (!system && data->handler == HANDLER_ONMATCH) {
3886 system = data->match_data.event_system;
3887 event = data->match_data.event;
3888 }
3889
3890 if (!event)
3891 goto free;
3892 /*
3893 * At this point, we're looking at a field on another
3894 * event. Because we can't modify a hist trigger on
3895 * another event to add a variable for a field, we need
3896 * to create a new trigger on that event and create the
3897 * variable at the same time.
3898 */
3899 hist_field = create_field_var_hist(hist_data, system, event, var);
3900 if (IS_ERR(hist_field))
3901 goto free;
3902 }
3903 out:
3904 return hist_field;
3905 free:
3906 destroy_field_var(field_var);
3907 hist_field = NULL;
3908 goto out;
3909 }
3910
trace_action_create(struct hist_trigger_data * hist_data,struct action_data * data)3911 static int trace_action_create(struct hist_trigger_data *hist_data,
3912 struct action_data *data)
3913 {
3914 struct trace_array *tr = hist_data->event_file->tr;
3915 char *event_name, *param, *system = NULL;
3916 struct hist_field *hist_field, *var_ref;
3917 unsigned int i;
3918 unsigned int field_pos = 0;
3919 struct synth_event *event;
3920 char *synth_event_name;
3921 int var_ref_idx, ret = 0;
3922
3923 lockdep_assert_held(&event_mutex);
3924
3925 if (data->use_trace_keyword)
3926 synth_event_name = data->synth_event_name;
3927 else
3928 synth_event_name = data->action_name;
3929
3930 event = find_synth_event(synth_event_name);
3931 if (!event) {
3932 hist_err(tr, HIST_ERR_SYNTH_EVENT_NOT_FOUND, errpos(synth_event_name));
3933 return -EINVAL;
3934 }
3935
3936 event->ref++;
3937
3938 for (i = 0; i < data->n_params; i++) {
3939 char *p;
3940
3941 p = param = kstrdup(data->params[i], GFP_KERNEL);
3942 if (!param) {
3943 ret = -ENOMEM;
3944 goto err;
3945 }
3946
3947 system = strsep(¶m, ".");
3948 if (!param) {
3949 param = (char *)system;
3950 system = event_name = NULL;
3951 } else {
3952 event_name = strsep(¶m, ".");
3953 if (!param) {
3954 kfree(p);
3955 ret = -EINVAL;
3956 goto err;
3957 }
3958 }
3959
3960 if (param[0] == '$')
3961 hist_field = trace_action_find_var(hist_data, data,
3962 system, event_name,
3963 param);
3964 else
3965 hist_field = trace_action_create_field_var(hist_data,
3966 data,
3967 system,
3968 event_name,
3969 param);
3970
3971 if (!hist_field) {
3972 kfree(p);
3973 ret = -EINVAL;
3974 goto err;
3975 }
3976
3977 if (check_synth_field(event, hist_field, field_pos) == 0) {
3978 var_ref = create_var_ref(hist_data, hist_field,
3979 system, event_name);
3980 if (!var_ref) {
3981 kfree(p);
3982 ret = -ENOMEM;
3983 goto err;
3984 }
3985
3986 var_ref_idx = find_var_ref_idx(hist_data, var_ref);
3987 if (WARN_ON(var_ref_idx < 0)) {
3988 kfree(p);
3989 ret = var_ref_idx;
3990 goto err;
3991 }
3992
3993 data->var_ref_idx[i] = var_ref_idx;
3994
3995 field_pos++;
3996 kfree(p);
3997 continue;
3998 }
3999
4000 hist_err(tr, HIST_ERR_SYNTH_TYPE_MISMATCH, errpos(param));
4001 kfree(p);
4002 ret = -EINVAL;
4003 goto err;
4004 }
4005
4006 if (field_pos != event->n_fields) {
4007 hist_err(tr, HIST_ERR_SYNTH_COUNT_MISMATCH, errpos(event->name));
4008 ret = -EINVAL;
4009 goto err;
4010 }
4011
4012 data->synth_event = event;
4013 out:
4014 return ret;
4015 err:
4016 event->ref--;
4017
4018 goto out;
4019 }
4020
action_create(struct hist_trigger_data * hist_data,struct action_data * data)4021 static int action_create(struct hist_trigger_data *hist_data,
4022 struct action_data *data)
4023 {
4024 struct trace_event_file *file = hist_data->event_file;
4025 struct trace_array *tr = file->tr;
4026 struct track_data *track_data;
4027 struct field_var *field_var;
4028 unsigned int i;
4029 char *param;
4030 int ret = 0;
4031
4032 if (data->action == ACTION_TRACE)
4033 return trace_action_create(hist_data, data);
4034
4035 if (data->action == ACTION_SNAPSHOT) {
4036 track_data = track_data_alloc(hist_data->key_size, data, hist_data);
4037 if (IS_ERR(track_data)) {
4038 ret = PTR_ERR(track_data);
4039 goto out;
4040 }
4041
4042 ret = tracing_snapshot_cond_enable(file->tr, track_data,
4043 cond_snapshot_update);
4044 if (ret)
4045 track_data_free(track_data);
4046
4047 goto out;
4048 }
4049
4050 if (data->action == ACTION_SAVE) {
4051 if (hist_data->n_save_vars) {
4052 ret = -EEXIST;
4053 hist_err(tr, HIST_ERR_TOO_MANY_SAVE_ACTIONS, 0);
4054 goto out;
4055 }
4056
4057 for (i = 0; i < data->n_params; i++) {
4058 param = kstrdup(data->params[i], GFP_KERNEL);
4059 if (!param) {
4060 ret = -ENOMEM;
4061 goto out;
4062 }
4063
4064 field_var = create_target_field_var(hist_data, NULL, NULL, param);
4065 if (IS_ERR(field_var)) {
4066 hist_err(tr, HIST_ERR_FIELD_VAR_CREATE_FAIL,
4067 errpos(param));
4068 ret = PTR_ERR(field_var);
4069 kfree(param);
4070 goto out;
4071 }
4072
4073 hist_data->save_vars[hist_data->n_save_vars++] = field_var;
4074 if (field_var->val->flags & HIST_FIELD_FL_STRING)
4075 hist_data->n_save_var_str++;
4076 kfree(param);
4077 }
4078 }
4079 out:
4080 return ret;
4081 }
4082
onmatch_create(struct hist_trigger_data * hist_data,struct action_data * data)4083 static int onmatch_create(struct hist_trigger_data *hist_data,
4084 struct action_data *data)
4085 {
4086 return action_create(hist_data, data);
4087 }
4088
onmatch_parse(struct trace_array * tr,char * str)4089 static struct action_data *onmatch_parse(struct trace_array *tr, char *str)
4090 {
4091 char *match_event, *match_event_system;
4092 struct action_data *data;
4093 int ret = -EINVAL;
4094
4095 data = kzalloc(sizeof(*data), GFP_KERNEL);
4096 if (!data)
4097 return ERR_PTR(-ENOMEM);
4098
4099 match_event = strsep(&str, ")");
4100 if (!match_event || !str) {
4101 hist_err(tr, HIST_ERR_NO_CLOSING_PAREN, errpos(match_event));
4102 goto free;
4103 }
4104
4105 match_event_system = strsep(&match_event, ".");
4106 if (!match_event) {
4107 hist_err(tr, HIST_ERR_SUBSYS_NOT_FOUND, errpos(match_event_system));
4108 goto free;
4109 }
4110
4111 if (IS_ERR(event_file(tr, match_event_system, match_event))) {
4112 hist_err(tr, HIST_ERR_INVALID_SUBSYS_EVENT, errpos(match_event));
4113 goto free;
4114 }
4115
4116 data->match_data.event = kstrdup(match_event, GFP_KERNEL);
4117 if (!data->match_data.event) {
4118 ret = -ENOMEM;
4119 goto free;
4120 }
4121
4122 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL);
4123 if (!data->match_data.event_system) {
4124 ret = -ENOMEM;
4125 goto free;
4126 }
4127
4128 ret = action_parse(tr, str, data, HANDLER_ONMATCH);
4129 if (ret)
4130 goto free;
4131 out:
4132 return data;
4133 free:
4134 onmatch_destroy(data);
4135 data = ERR_PTR(ret);
4136 goto out;
4137 }
4138
create_hitcount_val(struct hist_trigger_data * hist_data)4139 static int create_hitcount_val(struct hist_trigger_data *hist_data)
4140 {
4141 hist_data->fields[HITCOUNT_IDX] =
4142 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL);
4143 if (!hist_data->fields[HITCOUNT_IDX])
4144 return -ENOMEM;
4145
4146 hist_data->n_vals++;
4147 hist_data->n_fields++;
4148
4149 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
4150 return -EINVAL;
4151
4152 return 0;
4153 }
4154
__create_val_field(struct hist_trigger_data * hist_data,unsigned int val_idx,struct trace_event_file * file,char * var_name,char * field_str,unsigned long flags)4155 static int __create_val_field(struct hist_trigger_data *hist_data,
4156 unsigned int val_idx,
4157 struct trace_event_file *file,
4158 char *var_name, char *field_str,
4159 unsigned long flags)
4160 {
4161 struct hist_field *hist_field;
4162 int ret = 0, n_subexprs = 0;
4163
4164 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, &n_subexprs);
4165 if (IS_ERR(hist_field)) {
4166 ret = PTR_ERR(hist_field);
4167 goto out;
4168 }
4169
4170 hist_data->fields[val_idx] = hist_field;
4171
4172 ++hist_data->n_vals;
4173 ++hist_data->n_fields;
4174
4175 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
4176 ret = -EINVAL;
4177 out:
4178 return ret;
4179 }
4180
create_val_field(struct hist_trigger_data * hist_data,unsigned int val_idx,struct trace_event_file * file,char * field_str)4181 static int create_val_field(struct hist_trigger_data *hist_data,
4182 unsigned int val_idx,
4183 struct trace_event_file *file,
4184 char *field_str)
4185 {
4186 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
4187 return -EINVAL;
4188
4189 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
4190 }
4191
4192 static const char no_comm[] = "(no comm)";
4193
hist_field_execname(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)4194 static u64 hist_field_execname(struct hist_field *hist_field,
4195 struct tracing_map_elt *elt,
4196 struct trace_buffer *buffer,
4197 struct ring_buffer_event *rbe,
4198 void *event)
4199 {
4200 struct hist_elt_data *elt_data;
4201
4202 if (WARN_ON_ONCE(!elt))
4203 return (u64)(unsigned long)no_comm;
4204
4205 elt_data = elt->private_data;
4206
4207 if (WARN_ON_ONCE(!elt_data->comm))
4208 return (u64)(unsigned long)no_comm;
4209
4210 return (u64)(unsigned long)(elt_data->comm);
4211 }
4212
hist_fn_call(struct hist_field * hist_field,struct tracing_map_elt * elt,struct trace_buffer * buffer,struct ring_buffer_event * rbe,void * event)4213 static u64 hist_fn_call(struct hist_field *hist_field,
4214 struct tracing_map_elt *elt,
4215 struct trace_buffer *buffer,
4216 struct ring_buffer_event *rbe,
4217 void *event)
4218 {
4219 switch (hist_field->fn_num) {
4220 case HIST_FIELD_FN_VAR_REF:
4221 return hist_field_var_ref(hist_field, elt, buffer, rbe, event);
4222 case HIST_FIELD_FN_COUNTER:
4223 return hist_field_counter(hist_field, elt, buffer, rbe, event);
4224 case HIST_FIELD_FN_CONST:
4225 return hist_field_const(hist_field, elt, buffer, rbe, event);
4226 case HIST_FIELD_FN_LOG2:
4227 return hist_field_log2(hist_field, elt, buffer, rbe, event);
4228 case HIST_FIELD_FN_BUCKET:
4229 return hist_field_bucket(hist_field, elt, buffer, rbe, event);
4230 case HIST_FIELD_FN_TIMESTAMP:
4231 return hist_field_timestamp(hist_field, elt, buffer, rbe, event);
4232 case HIST_FIELD_FN_CPU:
4233 return hist_field_cpu(hist_field, elt, buffer, rbe, event);
4234 case HIST_FIELD_FN_STRING:
4235 return hist_field_string(hist_field, elt, buffer, rbe, event);
4236 case HIST_FIELD_FN_DYNSTRING:
4237 return hist_field_dynstring(hist_field, elt, buffer, rbe, event);
4238 case HIST_FIELD_FN_RELDYNSTRING:
4239 return hist_field_reldynstring(hist_field, elt, buffer, rbe, event);
4240 case HIST_FIELD_FN_PSTRING:
4241 return hist_field_pstring(hist_field, elt, buffer, rbe, event);
4242 case HIST_FIELD_FN_S64:
4243 return hist_field_s64(hist_field, elt, buffer, rbe, event);
4244 case HIST_FIELD_FN_U64:
4245 return hist_field_u64(hist_field, elt, buffer, rbe, event);
4246 case HIST_FIELD_FN_S32:
4247 return hist_field_s32(hist_field, elt, buffer, rbe, event);
4248 case HIST_FIELD_FN_U32:
4249 return hist_field_u32(hist_field, elt, buffer, rbe, event);
4250 case HIST_FIELD_FN_S16:
4251 return hist_field_s16(hist_field, elt, buffer, rbe, event);
4252 case HIST_FIELD_FN_U16:
4253 return hist_field_u16(hist_field, elt, buffer, rbe, event);
4254 case HIST_FIELD_FN_S8:
4255 return hist_field_s8(hist_field, elt, buffer, rbe, event);
4256 case HIST_FIELD_FN_U8:
4257 return hist_field_u8(hist_field, elt, buffer, rbe, event);
4258 case HIST_FIELD_FN_UMINUS:
4259 return hist_field_unary_minus(hist_field, elt, buffer, rbe, event);
4260 case HIST_FIELD_FN_MINUS:
4261 return hist_field_minus(hist_field, elt, buffer, rbe, event);
4262 case HIST_FIELD_FN_PLUS:
4263 return hist_field_plus(hist_field, elt, buffer, rbe, event);
4264 case HIST_FIELD_FN_DIV:
4265 return hist_field_div(hist_field, elt, buffer, rbe, event);
4266 case HIST_FIELD_FN_MULT:
4267 return hist_field_mult(hist_field, elt, buffer, rbe, event);
4268 case HIST_FIELD_FN_DIV_POWER2:
4269 return div_by_power_of_two(hist_field, elt, buffer, rbe, event);
4270 case HIST_FIELD_FN_DIV_NOT_POWER2:
4271 return div_by_not_power_of_two(hist_field, elt, buffer, rbe, event);
4272 case HIST_FIELD_FN_DIV_MULT_SHIFT:
4273 return div_by_mult_and_shift(hist_field, elt, buffer, rbe, event);
4274 case HIST_FIELD_FN_EXECNAME:
4275 return hist_field_execname(hist_field, elt, buffer, rbe, event);
4276 default:
4277 return 0;
4278 }
4279 }
4280
4281 /* Convert a var that points to common_pid.execname to a string */
update_var_execname(struct hist_field * hist_field)4282 static void update_var_execname(struct hist_field *hist_field)
4283 {
4284 hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR |
4285 HIST_FIELD_FL_EXECNAME;
4286 hist_field->size = MAX_FILTER_STR_VAL;
4287 hist_field->is_signed = 0;
4288
4289 kfree_const(hist_field->type);
4290 hist_field->type = "char[]";
4291
4292 hist_field->fn_num = HIST_FIELD_FN_EXECNAME;
4293 }
4294
create_var_field(struct hist_trigger_data * hist_data,unsigned int val_idx,struct trace_event_file * file,char * var_name,char * expr_str)4295 static int create_var_field(struct hist_trigger_data *hist_data,
4296 unsigned int val_idx,
4297 struct trace_event_file *file,
4298 char *var_name, char *expr_str)
4299 {
4300 struct trace_array *tr = hist_data->event_file->tr;
4301 unsigned long flags = 0;
4302 int ret;
4303
4304 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
4305 return -EINVAL;
4306
4307 if (find_var(hist_data, file, var_name) && !hist_data->remove) {
4308 hist_err(tr, HIST_ERR_DUPLICATE_VAR, errpos(var_name));
4309 return -EINVAL;
4310 }
4311
4312 flags |= HIST_FIELD_FL_VAR;
4313 hist_data->n_vars++;
4314 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX))
4315 return -EINVAL;
4316
4317 ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags);
4318
4319 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME)
4320 update_var_execname(hist_data->fields[val_idx]);
4321
4322 if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING)
4323 hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++;
4324
4325 return ret;
4326 }
4327
create_val_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)4328 static int create_val_fields(struct hist_trigger_data *hist_data,
4329 struct trace_event_file *file)
4330 {
4331 char *fields_str, *field_str;
4332 unsigned int i, j = 1;
4333 int ret;
4334
4335 ret = create_hitcount_val(hist_data);
4336 if (ret)
4337 goto out;
4338
4339 fields_str = hist_data->attrs->vals_str;
4340 if (!fields_str)
4341 goto out;
4342
4343 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
4344 j < TRACING_MAP_VALS_MAX; i++) {
4345 field_str = strsep(&fields_str, ",");
4346 if (!field_str)
4347 break;
4348
4349 if (strcmp(field_str, "hitcount") == 0)
4350 continue;
4351
4352 ret = create_val_field(hist_data, j++, file, field_str);
4353 if (ret)
4354 goto out;
4355 }
4356
4357 if (fields_str && (strcmp(fields_str, "hitcount") != 0))
4358 ret = -EINVAL;
4359 out:
4360 return ret;
4361 }
4362
create_key_field(struct hist_trigger_data * hist_data,unsigned int key_idx,unsigned int key_offset,struct trace_event_file * file,char * field_str)4363 static int create_key_field(struct hist_trigger_data *hist_data,
4364 unsigned int key_idx,
4365 unsigned int key_offset,
4366 struct trace_event_file *file,
4367 char *field_str)
4368 {
4369 struct trace_array *tr = hist_data->event_file->tr;
4370 struct hist_field *hist_field = NULL;
4371 unsigned long flags = 0;
4372 unsigned int key_size;
4373 int ret = 0, n_subexprs = 0;
4374
4375 if (WARN_ON(key_idx >= HIST_FIELDS_MAX))
4376 return -EINVAL;
4377
4378 flags |= HIST_FIELD_FL_KEY;
4379
4380 if (strcmp(field_str, "stacktrace") == 0) {
4381 flags |= HIST_FIELD_FL_STACKTRACE;
4382 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH;
4383 hist_field = create_hist_field(hist_data, NULL, flags, NULL);
4384 } else {
4385 hist_field = parse_expr(hist_data, file, field_str, flags,
4386 NULL, &n_subexprs);
4387 if (IS_ERR(hist_field)) {
4388 ret = PTR_ERR(hist_field);
4389 goto out;
4390 }
4391
4392 if (field_has_hist_vars(hist_field, 0)) {
4393 hist_err(tr, HIST_ERR_INVALID_REF_KEY, errpos(field_str));
4394 destroy_hist_field(hist_field, 0);
4395 ret = -EINVAL;
4396 goto out;
4397 }
4398
4399 key_size = hist_field->size;
4400 }
4401
4402 hist_data->fields[key_idx] = hist_field;
4403
4404 key_size = ALIGN(key_size, sizeof(u64));
4405 hist_data->fields[key_idx]->size = key_size;
4406 hist_data->fields[key_idx]->offset = key_offset;
4407
4408 hist_data->key_size += key_size;
4409
4410 if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
4411 ret = -EINVAL;
4412 goto out;
4413 }
4414
4415 hist_data->n_keys++;
4416 hist_data->n_fields++;
4417
4418 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX))
4419 return -EINVAL;
4420
4421 ret = key_size;
4422 out:
4423 return ret;
4424 }
4425
create_key_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)4426 static int create_key_fields(struct hist_trigger_data *hist_data,
4427 struct trace_event_file *file)
4428 {
4429 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals;
4430 char *fields_str, *field_str;
4431 int ret = -EINVAL;
4432
4433 fields_str = hist_data->attrs->keys_str;
4434 if (!fields_str)
4435 goto out;
4436
4437 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
4438 field_str = strsep(&fields_str, ",");
4439 if (!field_str)
4440 break;
4441 ret = create_key_field(hist_data, i, key_offset,
4442 file, field_str);
4443 if (ret < 0)
4444 goto out;
4445 key_offset += ret;
4446 }
4447 if (fields_str) {
4448 ret = -EINVAL;
4449 goto out;
4450 }
4451 ret = 0;
4452 out:
4453 return ret;
4454 }
4455
create_var_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)4456 static int create_var_fields(struct hist_trigger_data *hist_data,
4457 struct trace_event_file *file)
4458 {
4459 unsigned int i, j = hist_data->n_vals;
4460 int ret = 0;
4461
4462 unsigned int n_vars = hist_data->attrs->var_defs.n_vars;
4463
4464 for (i = 0; i < n_vars; i++) {
4465 char *var_name = hist_data->attrs->var_defs.name[i];
4466 char *expr = hist_data->attrs->var_defs.expr[i];
4467
4468 ret = create_var_field(hist_data, j++, file, var_name, expr);
4469 if (ret)
4470 goto out;
4471 }
4472 out:
4473 return ret;
4474 }
4475
free_var_defs(struct hist_trigger_data * hist_data)4476 static void free_var_defs(struct hist_trigger_data *hist_data)
4477 {
4478 unsigned int i;
4479
4480 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
4481 kfree(hist_data->attrs->var_defs.name[i]);
4482 kfree(hist_data->attrs->var_defs.expr[i]);
4483 }
4484
4485 hist_data->attrs->var_defs.n_vars = 0;
4486 }
4487
parse_var_defs(struct hist_trigger_data * hist_data)4488 static int parse_var_defs(struct hist_trigger_data *hist_data)
4489 {
4490 struct trace_array *tr = hist_data->event_file->tr;
4491 char *s, *str, *var_name, *field_str;
4492 unsigned int i, j, n_vars = 0;
4493 int ret = 0;
4494
4495 for (i = 0; i < hist_data->attrs->n_assignments; i++) {
4496 str = hist_data->attrs->assignment_str[i];
4497 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) {
4498 field_str = strsep(&str, ",");
4499 if (!field_str)
4500 break;
4501
4502 var_name = strsep(&field_str, "=");
4503 if (!var_name || !field_str) {
4504 hist_err(tr, HIST_ERR_MALFORMED_ASSIGNMENT,
4505 errpos(var_name));
4506 ret = -EINVAL;
4507 goto free;
4508 }
4509
4510 if (n_vars == TRACING_MAP_VARS_MAX) {
4511 hist_err(tr, HIST_ERR_TOO_MANY_VARS, errpos(var_name));
4512 ret = -EINVAL;
4513 goto free;
4514 }
4515
4516 s = kstrdup(var_name, GFP_KERNEL);
4517 if (!s) {
4518 ret = -ENOMEM;
4519 goto free;
4520 }
4521 hist_data->attrs->var_defs.name[n_vars] = s;
4522
4523 s = kstrdup(field_str, GFP_KERNEL);
4524 if (!s) {
4525 kfree(hist_data->attrs->var_defs.name[n_vars]);
4526 hist_data->attrs->var_defs.name[n_vars] = NULL;
4527 ret = -ENOMEM;
4528 goto free;
4529 }
4530 hist_data->attrs->var_defs.expr[n_vars++] = s;
4531
4532 hist_data->attrs->var_defs.n_vars = n_vars;
4533 }
4534 }
4535
4536 return ret;
4537 free:
4538 free_var_defs(hist_data);
4539
4540 return ret;
4541 }
4542
create_hist_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)4543 static int create_hist_fields(struct hist_trigger_data *hist_data,
4544 struct trace_event_file *file)
4545 {
4546 int ret;
4547
4548 ret = parse_var_defs(hist_data);
4549 if (ret)
4550 return ret;
4551
4552 ret = create_val_fields(hist_data, file);
4553 if (ret)
4554 goto out;
4555
4556 ret = create_var_fields(hist_data, file);
4557 if (ret)
4558 goto out;
4559
4560 ret = create_key_fields(hist_data, file);
4561
4562 out:
4563 free_var_defs(hist_data);
4564
4565 return ret;
4566 }
4567
is_descending(struct trace_array * tr,const char * str)4568 static int is_descending(struct trace_array *tr, const char *str)
4569 {
4570 if (!str)
4571 return 0;
4572
4573 if (strcmp(str, "descending") == 0)
4574 return 1;
4575
4576 if (strcmp(str, "ascending") == 0)
4577 return 0;
4578
4579 hist_err(tr, HIST_ERR_INVALID_SORT_MODIFIER, errpos((char *)str));
4580
4581 return -EINVAL;
4582 }
4583
create_sort_keys(struct hist_trigger_data * hist_data)4584 static int create_sort_keys(struct hist_trigger_data *hist_data)
4585 {
4586 struct trace_array *tr = hist_data->event_file->tr;
4587 char *fields_str = hist_data->attrs->sort_key_str;
4588 struct tracing_map_sort_key *sort_key;
4589 int descending, ret = 0;
4590 unsigned int i, j, k;
4591
4592 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
4593
4594 if (!fields_str)
4595 goto out;
4596
4597 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
4598 struct hist_field *hist_field;
4599 char *field_str, *field_name;
4600 const char *test_name;
4601
4602 sort_key = &hist_data->sort_keys[i];
4603
4604 field_str = strsep(&fields_str, ",");
4605 if (!field_str)
4606 break;
4607
4608 if (!*field_str) {
4609 ret = -EINVAL;
4610 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort="));
4611 break;
4612 }
4613
4614 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) {
4615 hist_err(tr, HIST_ERR_TOO_MANY_SORT_FIELDS, errpos("sort="));
4616 ret = -EINVAL;
4617 break;
4618 }
4619
4620 field_name = strsep(&field_str, ".");
4621 if (!field_name || !*field_name) {
4622 ret = -EINVAL;
4623 hist_err(tr, HIST_ERR_EMPTY_SORT_FIELD, errpos("sort="));
4624 break;
4625 }
4626
4627 if (strcmp(field_name, "hitcount") == 0) {
4628 descending = is_descending(tr, field_str);
4629 if (descending < 0) {
4630 ret = descending;
4631 break;
4632 }
4633 sort_key->descending = descending;
4634 continue;
4635 }
4636
4637 for (j = 1, k = 1; j < hist_data->n_fields; j++) {
4638 unsigned int idx;
4639
4640 hist_field = hist_data->fields[j];
4641 if (hist_field->flags & HIST_FIELD_FL_VAR)
4642 continue;
4643
4644 idx = k++;
4645
4646 test_name = hist_field_name(hist_field, 0);
4647
4648 if (strcmp(field_name, test_name) == 0) {
4649 sort_key->field_idx = idx;
4650 descending = is_descending(tr, field_str);
4651 if (descending < 0) {
4652 ret = descending;
4653 goto out;
4654 }
4655 sort_key->descending = descending;
4656 break;
4657 }
4658 }
4659 if (j == hist_data->n_fields) {
4660 ret = -EINVAL;
4661 hist_err(tr, HIST_ERR_INVALID_SORT_FIELD, errpos(field_name));
4662 break;
4663 }
4664 }
4665
4666 hist_data->n_sort_keys = i;
4667 out:
4668 return ret;
4669 }
4670
destroy_actions(struct hist_trigger_data * hist_data)4671 static void destroy_actions(struct hist_trigger_data *hist_data)
4672 {
4673 unsigned int i;
4674
4675 for (i = 0; i < hist_data->n_actions; i++) {
4676 struct action_data *data = hist_data->actions[i];
4677
4678 if (data->handler == HANDLER_ONMATCH)
4679 onmatch_destroy(data);
4680 else if (data->handler == HANDLER_ONMAX ||
4681 data->handler == HANDLER_ONCHANGE)
4682 track_data_destroy(hist_data, data);
4683 else
4684 kfree(data);
4685 }
4686 }
4687
parse_actions(struct hist_trigger_data * hist_data)4688 static int parse_actions(struct hist_trigger_data *hist_data)
4689 {
4690 struct trace_array *tr = hist_data->event_file->tr;
4691 struct action_data *data;
4692 unsigned int i;
4693 int ret = 0;
4694 char *str;
4695 int len;
4696
4697 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4698 str = hist_data->attrs->action_str[i];
4699
4700 if ((len = str_has_prefix(str, "onmatch("))) {
4701 char *action_str = str + len;
4702
4703 data = onmatch_parse(tr, action_str);
4704 if (IS_ERR(data)) {
4705 ret = PTR_ERR(data);
4706 break;
4707 }
4708 } else if ((len = str_has_prefix(str, "onmax("))) {
4709 char *action_str = str + len;
4710
4711 data = track_data_parse(hist_data, action_str,
4712 HANDLER_ONMAX);
4713 if (IS_ERR(data)) {
4714 ret = PTR_ERR(data);
4715 break;
4716 }
4717 } else if ((len = str_has_prefix(str, "onchange("))) {
4718 char *action_str = str + len;
4719
4720 data = track_data_parse(hist_data, action_str,
4721 HANDLER_ONCHANGE);
4722 if (IS_ERR(data)) {
4723 ret = PTR_ERR(data);
4724 break;
4725 }
4726 } else {
4727 ret = -EINVAL;
4728 break;
4729 }
4730
4731 hist_data->actions[hist_data->n_actions++] = data;
4732 }
4733
4734 return ret;
4735 }
4736
create_actions(struct hist_trigger_data * hist_data)4737 static int create_actions(struct hist_trigger_data *hist_data)
4738 {
4739 struct action_data *data;
4740 unsigned int i;
4741 int ret = 0;
4742
4743 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4744 data = hist_data->actions[i];
4745
4746 if (data->handler == HANDLER_ONMATCH) {
4747 ret = onmatch_create(hist_data, data);
4748 if (ret)
4749 break;
4750 } else if (data->handler == HANDLER_ONMAX ||
4751 data->handler == HANDLER_ONCHANGE) {
4752 ret = track_data_create(hist_data, data);
4753 if (ret)
4754 break;
4755 } else {
4756 ret = -EINVAL;
4757 break;
4758 }
4759 }
4760
4761 return ret;
4762 }
4763
print_actions(struct seq_file * m,struct hist_trigger_data * hist_data,struct tracing_map_elt * elt)4764 static void print_actions(struct seq_file *m,
4765 struct hist_trigger_data *hist_data,
4766 struct tracing_map_elt *elt)
4767 {
4768 unsigned int i;
4769
4770 for (i = 0; i < hist_data->n_actions; i++) {
4771 struct action_data *data = hist_data->actions[i];
4772
4773 if (data->action == ACTION_SNAPSHOT)
4774 continue;
4775
4776 if (data->handler == HANDLER_ONMAX ||
4777 data->handler == HANDLER_ONCHANGE)
4778 track_data_print(m, hist_data, elt, data);
4779 }
4780 }
4781
print_action_spec(struct seq_file * m,struct hist_trigger_data * hist_data,struct action_data * data)4782 static void print_action_spec(struct seq_file *m,
4783 struct hist_trigger_data *hist_data,
4784 struct action_data *data)
4785 {
4786 unsigned int i;
4787
4788 if (data->action == ACTION_SAVE) {
4789 for (i = 0; i < hist_data->n_save_vars; i++) {
4790 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name);
4791 if (i < hist_data->n_save_vars - 1)
4792 seq_puts(m, ",");
4793 }
4794 } else if (data->action == ACTION_TRACE) {
4795 if (data->use_trace_keyword)
4796 seq_printf(m, "%s", data->synth_event_name);
4797 for (i = 0; i < data->n_params; i++) {
4798 if (i || data->use_trace_keyword)
4799 seq_puts(m, ",");
4800 seq_printf(m, "%s", data->params[i]);
4801 }
4802 }
4803 }
4804
print_track_data_spec(struct seq_file * m,struct hist_trigger_data * hist_data,struct action_data * data)4805 static void print_track_data_spec(struct seq_file *m,
4806 struct hist_trigger_data *hist_data,
4807 struct action_data *data)
4808 {
4809 if (data->handler == HANDLER_ONMAX)
4810 seq_puts(m, ":onmax(");
4811 else if (data->handler == HANDLER_ONCHANGE)
4812 seq_puts(m, ":onchange(");
4813 seq_printf(m, "%s", data->track_data.var_str);
4814 seq_printf(m, ").%s(", data->action_name);
4815
4816 print_action_spec(m, hist_data, data);
4817
4818 seq_puts(m, ")");
4819 }
4820
print_onmatch_spec(struct seq_file * m,struct hist_trigger_data * hist_data,struct action_data * data)4821 static void print_onmatch_spec(struct seq_file *m,
4822 struct hist_trigger_data *hist_data,
4823 struct action_data *data)
4824 {
4825 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system,
4826 data->match_data.event);
4827
4828 seq_printf(m, "%s(", data->action_name);
4829
4830 print_action_spec(m, hist_data, data);
4831
4832 seq_puts(m, ")");
4833 }
4834
actions_match(struct hist_trigger_data * hist_data,struct hist_trigger_data * hist_data_test)4835 static bool actions_match(struct hist_trigger_data *hist_data,
4836 struct hist_trigger_data *hist_data_test)
4837 {
4838 unsigned int i, j;
4839
4840 if (hist_data->n_actions != hist_data_test->n_actions)
4841 return false;
4842
4843 for (i = 0; i < hist_data->n_actions; i++) {
4844 struct action_data *data = hist_data->actions[i];
4845 struct action_data *data_test = hist_data_test->actions[i];
4846 char *action_name, *action_name_test;
4847
4848 if (data->handler != data_test->handler)
4849 return false;
4850 if (data->action != data_test->action)
4851 return false;
4852
4853 if (data->n_params != data_test->n_params)
4854 return false;
4855
4856 for (j = 0; j < data->n_params; j++) {
4857 if (strcmp(data->params[j], data_test->params[j]) != 0)
4858 return false;
4859 }
4860
4861 if (data->use_trace_keyword)
4862 action_name = data->synth_event_name;
4863 else
4864 action_name = data->action_name;
4865
4866 if (data_test->use_trace_keyword)
4867 action_name_test = data_test->synth_event_name;
4868 else
4869 action_name_test = data_test->action_name;
4870
4871 if (strcmp(action_name, action_name_test) != 0)
4872 return false;
4873
4874 if (data->handler == HANDLER_ONMATCH) {
4875 if (strcmp(data->match_data.event_system,
4876 data_test->match_data.event_system) != 0)
4877 return false;
4878 if (strcmp(data->match_data.event,
4879 data_test->match_data.event) != 0)
4880 return false;
4881 } else if (data->handler == HANDLER_ONMAX ||
4882 data->handler == HANDLER_ONCHANGE) {
4883 if (strcmp(data->track_data.var_str,
4884 data_test->track_data.var_str) != 0)
4885 return false;
4886 }
4887 }
4888
4889 return true;
4890 }
4891
4892
print_actions_spec(struct seq_file * m,struct hist_trigger_data * hist_data)4893 static void print_actions_spec(struct seq_file *m,
4894 struct hist_trigger_data *hist_data)
4895 {
4896 unsigned int i;
4897
4898 for (i = 0; i < hist_data->n_actions; i++) {
4899 struct action_data *data = hist_data->actions[i];
4900
4901 if (data->handler == HANDLER_ONMATCH)
4902 print_onmatch_spec(m, hist_data, data);
4903 else if (data->handler == HANDLER_ONMAX ||
4904 data->handler == HANDLER_ONCHANGE)
4905 print_track_data_spec(m, hist_data, data);
4906 }
4907 }
4908
destroy_field_var_hists(struct hist_trigger_data * hist_data)4909 static void destroy_field_var_hists(struct hist_trigger_data *hist_data)
4910 {
4911 unsigned int i;
4912
4913 for (i = 0; i < hist_data->n_field_var_hists; i++) {
4914 kfree(hist_data->field_var_hists[i]->cmd);
4915 kfree(hist_data->field_var_hists[i]);
4916 }
4917 }
4918
destroy_hist_data(struct hist_trigger_data * hist_data)4919 static void destroy_hist_data(struct hist_trigger_data *hist_data)
4920 {
4921 if (!hist_data)
4922 return;
4923
4924 destroy_hist_trigger_attrs(hist_data->attrs);
4925 destroy_hist_fields(hist_data);
4926 tracing_map_destroy(hist_data->map);
4927
4928 destroy_actions(hist_data);
4929 destroy_field_vars(hist_data);
4930 destroy_field_var_hists(hist_data);
4931
4932 kfree(hist_data);
4933 }
4934
create_tracing_map_fields(struct hist_trigger_data * hist_data)4935 static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
4936 {
4937 struct tracing_map *map = hist_data->map;
4938 struct ftrace_event_field *field;
4939 struct hist_field *hist_field;
4940 int i, idx = 0;
4941
4942 for_each_hist_field(i, hist_data) {
4943 hist_field = hist_data->fields[i];
4944 if (hist_field->flags & HIST_FIELD_FL_KEY) {
4945 tracing_map_cmp_fn_t cmp_fn;
4946
4947 field = hist_field->field;
4948
4949 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
4950 cmp_fn = tracing_map_cmp_none;
4951 else if (!field || hist_field->flags & HIST_FIELD_FL_CPU)
4952 cmp_fn = tracing_map_cmp_num(hist_field->size,
4953 hist_field->is_signed);
4954 else if (is_string_field(field))
4955 cmp_fn = tracing_map_cmp_string;
4956 else
4957 cmp_fn = tracing_map_cmp_num(field->size,
4958 field->is_signed);
4959 idx = tracing_map_add_key_field(map,
4960 hist_field->offset,
4961 cmp_fn);
4962 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR))
4963 idx = tracing_map_add_sum_field(map);
4964
4965 if (idx < 0)
4966 return idx;
4967
4968 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4969 idx = tracing_map_add_var(map);
4970 if (idx < 0)
4971 return idx;
4972 hist_field->var.idx = idx;
4973 hist_field->var.hist_data = hist_data;
4974 }
4975 }
4976
4977 return 0;
4978 }
4979
4980 static struct hist_trigger_data *
create_hist_data(unsigned int map_bits,struct hist_trigger_attrs * attrs,struct trace_event_file * file,bool remove)4981 create_hist_data(unsigned int map_bits,
4982 struct hist_trigger_attrs *attrs,
4983 struct trace_event_file *file,
4984 bool remove)
4985 {
4986 const struct tracing_map_ops *map_ops = NULL;
4987 struct hist_trigger_data *hist_data;
4988 int ret = 0;
4989
4990 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL);
4991 if (!hist_data)
4992 return ERR_PTR(-ENOMEM);
4993
4994 hist_data->attrs = attrs;
4995 hist_data->remove = remove;
4996 hist_data->event_file = file;
4997
4998 ret = parse_actions(hist_data);
4999 if (ret)
5000 goto free;
5001
5002 ret = create_hist_fields(hist_data, file);
5003 if (ret)
5004 goto free;
5005
5006 ret = create_sort_keys(hist_data);
5007 if (ret)
5008 goto free;
5009
5010 map_ops = &hist_trigger_elt_data_ops;
5011
5012 hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
5013 map_ops, hist_data);
5014 if (IS_ERR(hist_data->map)) {
5015 ret = PTR_ERR(hist_data->map);
5016 hist_data->map = NULL;
5017 goto free;
5018 }
5019
5020 ret = create_tracing_map_fields(hist_data);
5021 if (ret)
5022 goto free;
5023 out:
5024 return hist_data;
5025 free:
5026 hist_data->attrs = NULL;
5027
5028 destroy_hist_data(hist_data);
5029
5030 hist_data = ERR_PTR(ret);
5031
5032 goto out;
5033 }
5034
hist_trigger_elt_update(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct trace_buffer * buffer,void * rec,struct ring_buffer_event * rbe,u64 * var_ref_vals)5035 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
5036 struct tracing_map_elt *elt,
5037 struct trace_buffer *buffer, void *rec,
5038 struct ring_buffer_event *rbe,
5039 u64 *var_ref_vals)
5040 {
5041 struct hist_elt_data *elt_data;
5042 struct hist_field *hist_field;
5043 unsigned int i, var_idx;
5044 u64 hist_val;
5045
5046 elt_data = elt->private_data;
5047 elt_data->var_ref_vals = var_ref_vals;
5048
5049 for_each_hist_val_field(i, hist_data) {
5050 hist_field = hist_data->fields[i];
5051 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec);
5052 if (hist_field->flags & HIST_FIELD_FL_VAR) {
5053 var_idx = hist_field->var.idx;
5054
5055 if (hist_field->flags & HIST_FIELD_FL_STRING) {
5056 unsigned int str_start, var_str_idx, idx;
5057 char *str, *val_str;
5058 unsigned int size;
5059
5060 str_start = hist_data->n_field_var_str +
5061 hist_data->n_save_var_str;
5062 var_str_idx = hist_field->var_str_idx;
5063 idx = str_start + var_str_idx;
5064
5065 str = elt_data->field_var_str[idx];
5066 val_str = (char *)(uintptr_t)hist_val;
5067
5068 size = min(hist_field->size, STR_VAR_LEN_MAX);
5069 strscpy(str, val_str, size);
5070
5071 hist_val = (u64)(uintptr_t)str;
5072 }
5073 tracing_map_set_var(elt, var_idx, hist_val);
5074 continue;
5075 }
5076 tracing_map_update_sum(elt, i, hist_val);
5077 }
5078
5079 for_each_hist_key_field(i, hist_data) {
5080 hist_field = hist_data->fields[i];
5081 if (hist_field->flags & HIST_FIELD_FL_VAR) {
5082 hist_val = hist_fn_call(hist_field, elt, buffer, rbe, rec);
5083 var_idx = hist_field->var.idx;
5084 tracing_map_set_var(elt, var_idx, hist_val);
5085 }
5086 }
5087
5088 update_field_vars(hist_data, elt, buffer, rbe, rec);
5089 }
5090
add_to_key(char * compound_key,void * key,struct hist_field * key_field,void * rec)5091 static inline void add_to_key(char *compound_key, void *key,
5092 struct hist_field *key_field, void *rec)
5093 {
5094 size_t size = key_field->size;
5095
5096 if (key_field->flags & HIST_FIELD_FL_STRING) {
5097 struct ftrace_event_field *field;
5098
5099 field = key_field->field;
5100 if (field->filter_type == FILTER_DYN_STRING ||
5101 field->filter_type == FILTER_RDYN_STRING)
5102 size = *(u32 *)(rec + field->offset) >> 16;
5103 else if (field->filter_type == FILTER_STATIC_STRING)
5104 size = field->size;
5105
5106 /* ensure NULL-termination */
5107 if (size > key_field->size - 1)
5108 size = key_field->size - 1;
5109
5110 strncpy(compound_key + key_field->offset, (char *)key, size);
5111 } else
5112 memcpy(compound_key + key_field->offset, key, size);
5113 }
5114
5115 static void
hist_trigger_actions(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct trace_buffer * buffer,void * rec,struct ring_buffer_event * rbe,void * key,u64 * var_ref_vals)5116 hist_trigger_actions(struct hist_trigger_data *hist_data,
5117 struct tracing_map_elt *elt,
5118 struct trace_buffer *buffer, void *rec,
5119 struct ring_buffer_event *rbe, void *key,
5120 u64 *var_ref_vals)
5121 {
5122 struct action_data *data;
5123 unsigned int i;
5124
5125 for (i = 0; i < hist_data->n_actions; i++) {
5126 data = hist_data->actions[i];
5127 data->fn(hist_data, elt, buffer, rec, rbe, key, data, var_ref_vals);
5128 }
5129 }
5130
event_hist_trigger(struct event_trigger_data * data,struct trace_buffer * buffer,void * rec,struct ring_buffer_event * rbe)5131 static void event_hist_trigger(struct event_trigger_data *data,
5132 struct trace_buffer *buffer, void *rec,
5133 struct ring_buffer_event *rbe)
5134 {
5135 struct hist_trigger_data *hist_data = data->private_data;
5136 bool use_compound_key = (hist_data->n_keys > 1);
5137 unsigned long entries[HIST_STACKTRACE_DEPTH];
5138 u64 var_ref_vals[TRACING_MAP_VARS_MAX];
5139 char compound_key[HIST_KEY_SIZE_MAX];
5140 struct tracing_map_elt *elt = NULL;
5141 struct hist_field *key_field;
5142 u64 field_contents;
5143 void *key = NULL;
5144 unsigned int i;
5145
5146 if (unlikely(!rbe))
5147 return;
5148
5149 memset(compound_key, 0, hist_data->key_size);
5150
5151 for_each_hist_key_field(i, hist_data) {
5152 key_field = hist_data->fields[i];
5153
5154 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
5155 memset(entries, 0, HIST_STACKTRACE_SIZE);
5156 stack_trace_save(entries, HIST_STACKTRACE_DEPTH,
5157 HIST_STACKTRACE_SKIP);
5158 key = entries;
5159 } else {
5160 field_contents = hist_fn_call(key_field, elt, buffer, rbe, rec);
5161 if (key_field->flags & HIST_FIELD_FL_STRING) {
5162 key = (void *)(unsigned long)field_contents;
5163 use_compound_key = true;
5164 } else
5165 key = (void *)&field_contents;
5166 }
5167
5168 if (use_compound_key)
5169 add_to_key(compound_key, key, key_field, rec);
5170 }
5171
5172 if (use_compound_key)
5173 key = compound_key;
5174
5175 if (hist_data->n_var_refs &&
5176 !resolve_var_refs(hist_data, key, var_ref_vals, false))
5177 return;
5178
5179 elt = tracing_map_insert(hist_data->map, key);
5180 if (!elt)
5181 return;
5182
5183 hist_trigger_elt_update(hist_data, elt, buffer, rec, rbe, var_ref_vals);
5184
5185 if (resolve_var_refs(hist_data, key, var_ref_vals, true))
5186 hist_trigger_actions(hist_data, elt, buffer, rec, rbe, key, var_ref_vals);
5187 }
5188
hist_trigger_stacktrace_print(struct seq_file * m,unsigned long * stacktrace_entries,unsigned int max_entries)5189 static void hist_trigger_stacktrace_print(struct seq_file *m,
5190 unsigned long *stacktrace_entries,
5191 unsigned int max_entries)
5192 {
5193 unsigned int spaces = 8;
5194 unsigned int i;
5195
5196 for (i = 0; i < max_entries; i++) {
5197 if (!stacktrace_entries[i])
5198 return;
5199
5200 seq_printf(m, "%*c", 1 + spaces, ' ');
5201 seq_printf(m, "%pS\n", (void*)stacktrace_entries[i]);
5202 }
5203 }
5204
hist_trigger_print_key(struct seq_file * m,struct hist_trigger_data * hist_data,void * key,struct tracing_map_elt * elt)5205 static void hist_trigger_print_key(struct seq_file *m,
5206 struct hist_trigger_data *hist_data,
5207 void *key,
5208 struct tracing_map_elt *elt)
5209 {
5210 struct hist_field *key_field;
5211 bool multiline = false;
5212 const char *field_name;
5213 unsigned int i;
5214 u64 uval;
5215
5216 seq_puts(m, "{ ");
5217
5218 for_each_hist_key_field(i, hist_data) {
5219 key_field = hist_data->fields[i];
5220
5221 if (i > hist_data->n_vals)
5222 seq_puts(m, ", ");
5223
5224 field_name = hist_field_name(key_field, 0);
5225
5226 if (key_field->flags & HIST_FIELD_FL_HEX) {
5227 uval = *(u64 *)(key + key_field->offset);
5228 seq_printf(m, "%s: %llx", field_name, uval);
5229 } else if (key_field->flags & HIST_FIELD_FL_SYM) {
5230 uval = *(u64 *)(key + key_field->offset);
5231 seq_printf(m, "%s: [%llx] %-45ps", field_name,
5232 uval, (void *)(uintptr_t)uval);
5233 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
5234 uval = *(u64 *)(key + key_field->offset);
5235 seq_printf(m, "%s: [%llx] %-55pS", field_name,
5236 uval, (void *)(uintptr_t)uval);
5237 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
5238 struct hist_elt_data *elt_data = elt->private_data;
5239 char *comm;
5240
5241 if (WARN_ON_ONCE(!elt_data))
5242 return;
5243
5244 comm = elt_data->comm;
5245
5246 uval = *(u64 *)(key + key_field->offset);
5247 seq_printf(m, "%s: %-16s[%10llu]", field_name,
5248 comm, uval);
5249 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
5250 const char *syscall_name;
5251
5252 uval = *(u64 *)(key + key_field->offset);
5253 syscall_name = get_syscall_name(uval);
5254 if (!syscall_name)
5255 syscall_name = "unknown_syscall";
5256
5257 seq_printf(m, "%s: %-30s[%3llu]", field_name,
5258 syscall_name, uval);
5259 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
5260 seq_puts(m, "stacktrace:\n");
5261 hist_trigger_stacktrace_print(m,
5262 key + key_field->offset,
5263 HIST_STACKTRACE_DEPTH);
5264 multiline = true;
5265 } else if (key_field->flags & HIST_FIELD_FL_LOG2) {
5266 seq_printf(m, "%s: ~ 2^%-2llu", field_name,
5267 *(u64 *)(key + key_field->offset));
5268 } else if (key_field->flags & HIST_FIELD_FL_BUCKET) {
5269 unsigned long buckets = key_field->buckets;
5270 uval = *(u64 *)(key + key_field->offset);
5271 seq_printf(m, "%s: ~ %llu-%llu", field_name,
5272 uval, uval + buckets -1);
5273 } else if (key_field->flags & HIST_FIELD_FL_STRING) {
5274 seq_printf(m, "%s: %-50s", field_name,
5275 (char *)(key + key_field->offset));
5276 } else {
5277 uval = *(u64 *)(key + key_field->offset);
5278 seq_printf(m, "%s: %10llu", field_name, uval);
5279 }
5280 }
5281
5282 if (!multiline)
5283 seq_puts(m, " ");
5284
5285 seq_puts(m, "}");
5286 }
5287
hist_trigger_entry_print(struct seq_file * m,struct hist_trigger_data * hist_data,void * key,struct tracing_map_elt * elt)5288 static void hist_trigger_entry_print(struct seq_file *m,
5289 struct hist_trigger_data *hist_data,
5290 void *key,
5291 struct tracing_map_elt *elt)
5292 {
5293 const char *field_name;
5294 unsigned int i;
5295
5296 hist_trigger_print_key(m, hist_data, key, elt);
5297
5298 seq_printf(m, " hitcount: %10llu",
5299 tracing_map_read_sum(elt, HITCOUNT_IDX));
5300
5301 for (i = 1; i < hist_data->n_vals; i++) {
5302 field_name = hist_field_name(hist_data->fields[i], 0);
5303
5304 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR ||
5305 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR)
5306 continue;
5307
5308 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) {
5309 seq_printf(m, " %s: %10llx", field_name,
5310 tracing_map_read_sum(elt, i));
5311 } else {
5312 seq_printf(m, " %s: %10llu", field_name,
5313 tracing_map_read_sum(elt, i));
5314 }
5315 }
5316
5317 print_actions(m, hist_data, elt);
5318
5319 seq_puts(m, "\n");
5320 }
5321
print_entries(struct seq_file * m,struct hist_trigger_data * hist_data)5322 static int print_entries(struct seq_file *m,
5323 struct hist_trigger_data *hist_data)
5324 {
5325 struct tracing_map_sort_entry **sort_entries = NULL;
5326 struct tracing_map *map = hist_data->map;
5327 int i, n_entries;
5328
5329 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys,
5330 hist_data->n_sort_keys,
5331 &sort_entries);
5332 if (n_entries < 0)
5333 return n_entries;
5334
5335 for (i = 0; i < n_entries; i++)
5336 hist_trigger_entry_print(m, hist_data,
5337 sort_entries[i]->key,
5338 sort_entries[i]->elt);
5339
5340 tracing_map_destroy_sort_entries(sort_entries, n_entries);
5341
5342 return n_entries;
5343 }
5344
hist_trigger_show(struct seq_file * m,struct event_trigger_data * data,int n)5345 static void hist_trigger_show(struct seq_file *m,
5346 struct event_trigger_data *data, int n)
5347 {
5348 struct hist_trigger_data *hist_data;
5349 int n_entries;
5350
5351 if (n > 0)
5352 seq_puts(m, "\n\n");
5353
5354 seq_puts(m, "# event histogram\n#\n# trigger info: ");
5355 data->ops->print(m, data);
5356 seq_puts(m, "#\n\n");
5357
5358 hist_data = data->private_data;
5359 n_entries = print_entries(m, hist_data);
5360 if (n_entries < 0)
5361 n_entries = 0;
5362
5363 track_data_snapshot_print(m, hist_data);
5364
5365 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
5366 (u64)atomic64_read(&hist_data->map->hits),
5367 n_entries, (u64)atomic64_read(&hist_data->map->drops));
5368 }
5369
hist_show(struct seq_file * m,void * v)5370 static int hist_show(struct seq_file *m, void *v)
5371 {
5372 struct event_trigger_data *data;
5373 struct trace_event_file *event_file;
5374 int n = 0, ret = 0;
5375
5376 mutex_lock(&event_mutex);
5377
5378 event_file = event_file_data(m->private);
5379 if (unlikely(!event_file)) {
5380 ret = -ENODEV;
5381 goto out_unlock;
5382 }
5383
5384 list_for_each_entry(data, &event_file->triggers, list) {
5385 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
5386 hist_trigger_show(m, data, n++);
5387 }
5388
5389 out_unlock:
5390 mutex_unlock(&event_mutex);
5391
5392 return ret;
5393 }
5394
event_hist_open(struct inode * inode,struct file * file)5395 static int event_hist_open(struct inode *inode, struct file *file)
5396 {
5397 int ret;
5398
5399 ret = security_locked_down(LOCKDOWN_TRACEFS);
5400 if (ret)
5401 return ret;
5402
5403 return single_open(file, hist_show, file);
5404 }
5405
5406 const struct file_operations event_hist_fops = {
5407 .open = event_hist_open,
5408 .read = seq_read,
5409 .llseek = seq_lseek,
5410 .release = single_release,
5411 };
5412
5413 #ifdef CONFIG_HIST_TRIGGERS_DEBUG
hist_field_debug_show_flags(struct seq_file * m,unsigned long flags)5414 static void hist_field_debug_show_flags(struct seq_file *m,
5415 unsigned long flags)
5416 {
5417 seq_puts(m, " flags:\n");
5418
5419 if (flags & HIST_FIELD_FL_KEY)
5420 seq_puts(m, " HIST_FIELD_FL_KEY\n");
5421 else if (flags & HIST_FIELD_FL_HITCOUNT)
5422 seq_puts(m, " VAL: HIST_FIELD_FL_HITCOUNT\n");
5423 else if (flags & HIST_FIELD_FL_VAR)
5424 seq_puts(m, " HIST_FIELD_FL_VAR\n");
5425 else if (flags & HIST_FIELD_FL_VAR_REF)
5426 seq_puts(m, " HIST_FIELD_FL_VAR_REF\n");
5427 else
5428 seq_puts(m, " VAL: normal u64 value\n");
5429
5430 if (flags & HIST_FIELD_FL_ALIAS)
5431 seq_puts(m, " HIST_FIELD_FL_ALIAS\n");
5432 else if (flags & HIST_FIELD_FL_CONST)
5433 seq_puts(m, " HIST_FIELD_FL_CONST\n");
5434 }
5435
hist_field_debug_show(struct seq_file * m,struct hist_field * field,unsigned long flags)5436 static int hist_field_debug_show(struct seq_file *m,
5437 struct hist_field *field, unsigned long flags)
5438 {
5439 if ((field->flags & flags) != flags) {
5440 seq_printf(m, "ERROR: bad flags - %lx\n", flags);
5441 return -EINVAL;
5442 }
5443
5444 hist_field_debug_show_flags(m, field->flags);
5445 if (field->field)
5446 seq_printf(m, " ftrace_event_field name: %s\n",
5447 field->field->name);
5448
5449 if (field->flags & HIST_FIELD_FL_VAR) {
5450 seq_printf(m, " var.name: %s\n", field->var.name);
5451 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
5452 field->var.idx);
5453 }
5454
5455 if (field->flags & HIST_FIELD_FL_CONST)
5456 seq_printf(m, " constant: %llu\n", field->constant);
5457
5458 if (field->flags & HIST_FIELD_FL_ALIAS)
5459 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n",
5460 field->var_ref_idx);
5461
5462 if (field->flags & HIST_FIELD_FL_VAR_REF) {
5463 seq_printf(m, " name: %s\n", field->name);
5464 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
5465 field->var.idx);
5466 seq_printf(m, " var.hist_data: %p\n", field->var.hist_data);
5467 seq_printf(m, " var_ref_idx (into hist_data->var_refs[]): %u\n",
5468 field->var_ref_idx);
5469 if (field->system)
5470 seq_printf(m, " system: %s\n", field->system);
5471 if (field->event_name)
5472 seq_printf(m, " event_name: %s\n", field->event_name);
5473 }
5474
5475 seq_printf(m, " type: %s\n", field->type);
5476 seq_printf(m, " size: %u\n", field->size);
5477 seq_printf(m, " is_signed: %u\n", field->is_signed);
5478
5479 return 0;
5480 }
5481
field_var_debug_show(struct seq_file * m,struct field_var * field_var,unsigned int i,bool save_vars)5482 static int field_var_debug_show(struct seq_file *m,
5483 struct field_var *field_var, unsigned int i,
5484 bool save_vars)
5485 {
5486 const char *vars_name = save_vars ? "save_vars" : "field_vars";
5487 struct hist_field *field;
5488 int ret = 0;
5489
5490 seq_printf(m, "\n hist_data->%s[%d]:\n", vars_name, i);
5491
5492 field = field_var->var;
5493
5494 seq_printf(m, "\n %s[%d].var:\n", vars_name, i);
5495
5496 hist_field_debug_show_flags(m, field->flags);
5497 seq_printf(m, " var.name: %s\n", field->var.name);
5498 seq_printf(m, " var.idx (into tracing_map_elt.vars[]): %u\n",
5499 field->var.idx);
5500
5501 field = field_var->val;
5502
5503 seq_printf(m, "\n %s[%d].val:\n", vars_name, i);
5504 if (field->field)
5505 seq_printf(m, " ftrace_event_field name: %s\n",
5506 field->field->name);
5507 else {
5508 ret = -EINVAL;
5509 goto out;
5510 }
5511
5512 seq_printf(m, " type: %s\n", field->type);
5513 seq_printf(m, " size: %u\n", field->size);
5514 seq_printf(m, " is_signed: %u\n", field->is_signed);
5515 out:
5516 return ret;
5517 }
5518
hist_action_debug_show(struct seq_file * m,struct action_data * data,int i)5519 static int hist_action_debug_show(struct seq_file *m,
5520 struct action_data *data, int i)
5521 {
5522 int ret = 0;
5523
5524 if (data->handler == HANDLER_ONMAX ||
5525 data->handler == HANDLER_ONCHANGE) {
5526 seq_printf(m, "\n hist_data->actions[%d].track_data.var_ref:\n", i);
5527 ret = hist_field_debug_show(m, data->track_data.var_ref,
5528 HIST_FIELD_FL_VAR_REF);
5529 if (ret)
5530 goto out;
5531
5532 seq_printf(m, "\n hist_data->actions[%d].track_data.track_var:\n", i);
5533 ret = hist_field_debug_show(m, data->track_data.track_var,
5534 HIST_FIELD_FL_VAR);
5535 if (ret)
5536 goto out;
5537 }
5538
5539 if (data->handler == HANDLER_ONMATCH) {
5540 seq_printf(m, "\n hist_data->actions[%d].match_data.event_system: %s\n",
5541 i, data->match_data.event_system);
5542 seq_printf(m, " hist_data->actions[%d].match_data.event: %s\n",
5543 i, data->match_data.event);
5544 }
5545 out:
5546 return ret;
5547 }
5548
hist_actions_debug_show(struct seq_file * m,struct hist_trigger_data * hist_data)5549 static int hist_actions_debug_show(struct seq_file *m,
5550 struct hist_trigger_data *hist_data)
5551 {
5552 int i, ret = 0;
5553
5554 if (hist_data->n_actions)
5555 seq_puts(m, "\n action tracking variables (for onmax()/onchange()/onmatch()):\n");
5556
5557 for (i = 0; i < hist_data->n_actions; i++) {
5558 struct action_data *action = hist_data->actions[i];
5559
5560 ret = hist_action_debug_show(m, action, i);
5561 if (ret)
5562 goto out;
5563 }
5564
5565 if (hist_data->n_save_vars)
5566 seq_puts(m, "\n save action variables (save() params):\n");
5567
5568 for (i = 0; i < hist_data->n_save_vars; i++) {
5569 ret = field_var_debug_show(m, hist_data->save_vars[i], i, true);
5570 if (ret)
5571 goto out;
5572 }
5573 out:
5574 return ret;
5575 }
5576
hist_trigger_debug_show(struct seq_file * m,struct event_trigger_data * data,int n)5577 static void hist_trigger_debug_show(struct seq_file *m,
5578 struct event_trigger_data *data, int n)
5579 {
5580 struct hist_trigger_data *hist_data;
5581 int i, ret;
5582
5583 if (n > 0)
5584 seq_puts(m, "\n\n");
5585
5586 seq_puts(m, "# event histogram\n#\n# trigger info: ");
5587 data->ops->print(m, data);
5588 seq_puts(m, "#\n\n");
5589
5590 hist_data = data->private_data;
5591
5592 seq_printf(m, "hist_data: %p\n\n", hist_data);
5593 seq_printf(m, " n_vals: %u\n", hist_data->n_vals);
5594 seq_printf(m, " n_keys: %u\n", hist_data->n_keys);
5595 seq_printf(m, " n_fields: %u\n", hist_data->n_fields);
5596
5597 seq_puts(m, "\n val fields:\n\n");
5598
5599 seq_puts(m, " hist_data->fields[0]:\n");
5600 ret = hist_field_debug_show(m, hist_data->fields[0],
5601 HIST_FIELD_FL_HITCOUNT);
5602 if (ret)
5603 return;
5604
5605 for (i = 1; i < hist_data->n_vals; i++) {
5606 seq_printf(m, "\n hist_data->fields[%d]:\n", i);
5607 ret = hist_field_debug_show(m, hist_data->fields[i], 0);
5608 if (ret)
5609 return;
5610 }
5611
5612 seq_puts(m, "\n key fields:\n");
5613
5614 for (i = hist_data->n_vals; i < hist_data->n_fields; i++) {
5615 seq_printf(m, "\n hist_data->fields[%d]:\n", i);
5616 ret = hist_field_debug_show(m, hist_data->fields[i],
5617 HIST_FIELD_FL_KEY);
5618 if (ret)
5619 return;
5620 }
5621
5622 if (hist_data->n_var_refs)
5623 seq_puts(m, "\n variable reference fields:\n");
5624
5625 for (i = 0; i < hist_data->n_var_refs; i++) {
5626 seq_printf(m, "\n hist_data->var_refs[%d]:\n", i);
5627 ret = hist_field_debug_show(m, hist_data->var_refs[i],
5628 HIST_FIELD_FL_VAR_REF);
5629 if (ret)
5630 return;
5631 }
5632
5633 if (hist_data->n_field_vars)
5634 seq_puts(m, "\n field variables:\n");
5635
5636 for (i = 0; i < hist_data->n_field_vars; i++) {
5637 ret = field_var_debug_show(m, hist_data->field_vars[i], i, false);
5638 if (ret)
5639 return;
5640 }
5641
5642 ret = hist_actions_debug_show(m, hist_data);
5643 if (ret)
5644 return;
5645 }
5646
hist_debug_show(struct seq_file * m,void * v)5647 static int hist_debug_show(struct seq_file *m, void *v)
5648 {
5649 struct event_trigger_data *data;
5650 struct trace_event_file *event_file;
5651 int n = 0, ret = 0;
5652
5653 mutex_lock(&event_mutex);
5654
5655 event_file = event_file_data(m->private);
5656 if (unlikely(!event_file)) {
5657 ret = -ENODEV;
5658 goto out_unlock;
5659 }
5660
5661 list_for_each_entry(data, &event_file->triggers, list) {
5662 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
5663 hist_trigger_debug_show(m, data, n++);
5664 }
5665
5666 out_unlock:
5667 mutex_unlock(&event_mutex);
5668
5669 return ret;
5670 }
5671
event_hist_debug_open(struct inode * inode,struct file * file)5672 static int event_hist_debug_open(struct inode *inode, struct file *file)
5673 {
5674 int ret;
5675
5676 ret = security_locked_down(LOCKDOWN_TRACEFS);
5677 if (ret)
5678 return ret;
5679
5680 return single_open(file, hist_debug_show, file);
5681 }
5682
5683 const struct file_operations event_hist_debug_fops = {
5684 .open = event_hist_debug_open,
5685 .read = seq_read,
5686 .llseek = seq_lseek,
5687 .release = single_release,
5688 };
5689 #endif
5690
hist_field_print(struct seq_file * m,struct hist_field * hist_field)5691 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
5692 {
5693 const char *field_name = hist_field_name(hist_field, 0);
5694
5695 if (hist_field->var.name)
5696 seq_printf(m, "%s=", hist_field->var.name);
5697
5698 if (hist_field->flags & HIST_FIELD_FL_CPU)
5699 seq_puts(m, "common_cpu");
5700 else if (hist_field->flags & HIST_FIELD_FL_CONST)
5701 seq_printf(m, "%llu", hist_field->constant);
5702 else if (field_name) {
5703 if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
5704 hist_field->flags & HIST_FIELD_FL_ALIAS)
5705 seq_putc(m, '$');
5706 seq_printf(m, "%s", field_name);
5707 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP)
5708 seq_puts(m, "common_timestamp");
5709
5710 if (hist_field->flags) {
5711 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) &&
5712 !(hist_field->flags & HIST_FIELD_FL_EXPR)) {
5713 const char *flags = get_hist_field_flags(hist_field);
5714
5715 if (flags)
5716 seq_printf(m, ".%s", flags);
5717 }
5718 }
5719 if (hist_field->buckets)
5720 seq_printf(m, "=%ld", hist_field->buckets);
5721 }
5722
event_hist_trigger_print(struct seq_file * m,struct event_trigger_data * data)5723 static int event_hist_trigger_print(struct seq_file *m,
5724 struct event_trigger_data *data)
5725 {
5726 struct hist_trigger_data *hist_data = data->private_data;
5727 struct hist_field *field;
5728 bool have_var = false;
5729 unsigned int i;
5730
5731 seq_puts(m, HIST_PREFIX);
5732
5733 if (data->name)
5734 seq_printf(m, "%s:", data->name);
5735
5736 seq_puts(m, "keys=");
5737
5738 for_each_hist_key_field(i, hist_data) {
5739 field = hist_data->fields[i];
5740
5741 if (i > hist_data->n_vals)
5742 seq_puts(m, ",");
5743
5744 if (field->flags & HIST_FIELD_FL_STACKTRACE)
5745 seq_puts(m, "stacktrace");
5746 else
5747 hist_field_print(m, field);
5748 }
5749
5750 seq_puts(m, ":vals=");
5751
5752 for_each_hist_val_field(i, hist_data) {
5753 field = hist_data->fields[i];
5754 if (field->flags & HIST_FIELD_FL_VAR) {
5755 have_var = true;
5756 continue;
5757 }
5758
5759 if (i == HITCOUNT_IDX)
5760 seq_puts(m, "hitcount");
5761 else {
5762 seq_puts(m, ",");
5763 hist_field_print(m, field);
5764 }
5765 }
5766
5767 if (have_var) {
5768 unsigned int n = 0;
5769
5770 seq_puts(m, ":");
5771
5772 for_each_hist_val_field(i, hist_data) {
5773 field = hist_data->fields[i];
5774
5775 if (field->flags & HIST_FIELD_FL_VAR) {
5776 if (n++)
5777 seq_puts(m, ",");
5778 hist_field_print(m, field);
5779 }
5780 }
5781 }
5782
5783 seq_puts(m, ":sort=");
5784
5785 for (i = 0; i < hist_data->n_sort_keys; i++) {
5786 struct tracing_map_sort_key *sort_key;
5787 unsigned int idx, first_key_idx;
5788
5789 /* skip VAR vals */
5790 first_key_idx = hist_data->n_vals - hist_data->n_vars;
5791
5792 sort_key = &hist_data->sort_keys[i];
5793 idx = sort_key->field_idx;
5794
5795 if (WARN_ON(idx >= HIST_FIELDS_MAX))
5796 return -EINVAL;
5797
5798 if (i > 0)
5799 seq_puts(m, ",");
5800
5801 if (idx == HITCOUNT_IDX)
5802 seq_puts(m, "hitcount");
5803 else {
5804 if (idx >= first_key_idx)
5805 idx += hist_data->n_vars;
5806 hist_field_print(m, hist_data->fields[idx]);
5807 }
5808
5809 if (sort_key->descending)
5810 seq_puts(m, ".descending");
5811 }
5812 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
5813 if (hist_data->enable_timestamps)
5814 seq_printf(m, ":clock=%s", hist_data->attrs->clock);
5815
5816 print_actions_spec(m, hist_data);
5817
5818 if (data->filter_str)
5819 seq_printf(m, " if %s", data->filter_str);
5820
5821 if (data->paused)
5822 seq_puts(m, " [paused]");
5823 else
5824 seq_puts(m, " [active]");
5825
5826 seq_putc(m, '\n');
5827
5828 return 0;
5829 }
5830
event_hist_trigger_init(struct event_trigger_data * data)5831 static int event_hist_trigger_init(struct event_trigger_data *data)
5832 {
5833 struct hist_trigger_data *hist_data = data->private_data;
5834
5835 if (!data->ref && hist_data->attrs->name)
5836 save_named_trigger(hist_data->attrs->name, data);
5837
5838 data->ref++;
5839
5840 return 0;
5841 }
5842
unregister_field_var_hists(struct hist_trigger_data * hist_data)5843 static void unregister_field_var_hists(struct hist_trigger_data *hist_data)
5844 {
5845 struct trace_event_file *file;
5846 unsigned int i;
5847 char *cmd;
5848 int ret;
5849
5850 for (i = 0; i < hist_data->n_field_var_hists; i++) {
5851 file = hist_data->field_var_hists[i]->hist_data->event_file;
5852 cmd = hist_data->field_var_hists[i]->cmd;
5853 ret = event_hist_trigger_parse(&trigger_hist_cmd, file,
5854 "!hist", "hist", cmd);
5855 WARN_ON_ONCE(ret < 0);
5856 }
5857 }
5858
event_hist_trigger_free(struct event_trigger_data * data)5859 static void event_hist_trigger_free(struct event_trigger_data *data)
5860 {
5861 struct hist_trigger_data *hist_data = data->private_data;
5862
5863 if (WARN_ON_ONCE(data->ref <= 0))
5864 return;
5865
5866 data->ref--;
5867 if (!data->ref) {
5868 if (data->name)
5869 del_named_trigger(data);
5870
5871 trigger_data_free(data);
5872
5873 remove_hist_vars(hist_data);
5874
5875 unregister_field_var_hists(hist_data);
5876
5877 destroy_hist_data(hist_data);
5878 }
5879 }
5880
5881 static struct event_trigger_ops event_hist_trigger_ops = {
5882 .trigger = event_hist_trigger,
5883 .print = event_hist_trigger_print,
5884 .init = event_hist_trigger_init,
5885 .free = event_hist_trigger_free,
5886 };
5887
event_hist_trigger_named_init(struct event_trigger_data * data)5888 static int event_hist_trigger_named_init(struct event_trigger_data *data)
5889 {
5890 data->ref++;
5891
5892 save_named_trigger(data->named_data->name, data);
5893
5894 event_hist_trigger_init(data->named_data);
5895
5896 return 0;
5897 }
5898
event_hist_trigger_named_free(struct event_trigger_data * data)5899 static void event_hist_trigger_named_free(struct event_trigger_data *data)
5900 {
5901 if (WARN_ON_ONCE(data->ref <= 0))
5902 return;
5903
5904 event_hist_trigger_free(data->named_data);
5905
5906 data->ref--;
5907 if (!data->ref) {
5908 del_named_trigger(data);
5909 trigger_data_free(data);
5910 }
5911 }
5912
5913 static struct event_trigger_ops event_hist_trigger_named_ops = {
5914 .trigger = event_hist_trigger,
5915 .print = event_hist_trigger_print,
5916 .init = event_hist_trigger_named_init,
5917 .free = event_hist_trigger_named_free,
5918 };
5919
event_hist_get_trigger_ops(char * cmd,char * param)5920 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
5921 char *param)
5922 {
5923 return &event_hist_trigger_ops;
5924 }
5925
hist_clear(struct event_trigger_data * data)5926 static void hist_clear(struct event_trigger_data *data)
5927 {
5928 struct hist_trigger_data *hist_data = data->private_data;
5929
5930 if (data->name)
5931 pause_named_trigger(data);
5932
5933 tracepoint_synchronize_unregister();
5934
5935 tracing_map_clear(hist_data->map);
5936
5937 if (data->name)
5938 unpause_named_trigger(data);
5939 }
5940
compatible_field(struct ftrace_event_field * field,struct ftrace_event_field * test_field)5941 static bool compatible_field(struct ftrace_event_field *field,
5942 struct ftrace_event_field *test_field)
5943 {
5944 if (field == test_field)
5945 return true;
5946 if (field == NULL || test_field == NULL)
5947 return false;
5948 if (strcmp(field->name, test_field->name) != 0)
5949 return false;
5950 if (strcmp(field->type, test_field->type) != 0)
5951 return false;
5952 if (field->size != test_field->size)
5953 return false;
5954 if (field->is_signed != test_field->is_signed)
5955 return false;
5956
5957 return true;
5958 }
5959
hist_trigger_match(struct event_trigger_data * data,struct event_trigger_data * data_test,struct event_trigger_data * named_data,bool ignore_filter)5960 static bool hist_trigger_match(struct event_trigger_data *data,
5961 struct event_trigger_data *data_test,
5962 struct event_trigger_data *named_data,
5963 bool ignore_filter)
5964 {
5965 struct tracing_map_sort_key *sort_key, *sort_key_test;
5966 struct hist_trigger_data *hist_data, *hist_data_test;
5967 struct hist_field *key_field, *key_field_test;
5968 unsigned int i;
5969
5970 if (named_data && (named_data != data_test) &&
5971 (named_data != data_test->named_data))
5972 return false;
5973
5974 if (!named_data && is_named_trigger(data_test))
5975 return false;
5976
5977 hist_data = data->private_data;
5978 hist_data_test = data_test->private_data;
5979
5980 if (hist_data->n_vals != hist_data_test->n_vals ||
5981 hist_data->n_fields != hist_data_test->n_fields ||
5982 hist_data->n_sort_keys != hist_data_test->n_sort_keys)
5983 return false;
5984
5985 if (!ignore_filter) {
5986 if ((data->filter_str && !data_test->filter_str) ||
5987 (!data->filter_str && data_test->filter_str))
5988 return false;
5989 }
5990
5991 for_each_hist_field(i, hist_data) {
5992 key_field = hist_data->fields[i];
5993 key_field_test = hist_data_test->fields[i];
5994
5995 if (key_field->flags != key_field_test->flags)
5996 return false;
5997 if (!compatible_field(key_field->field, key_field_test->field))
5998 return false;
5999 if (key_field->offset != key_field_test->offset)
6000 return false;
6001 if (key_field->size != key_field_test->size)
6002 return false;
6003 if (key_field->is_signed != key_field_test->is_signed)
6004 return false;
6005 if (!!key_field->var.name != !!key_field_test->var.name)
6006 return false;
6007 if (key_field->var.name &&
6008 strcmp(key_field->var.name, key_field_test->var.name) != 0)
6009 return false;
6010 }
6011
6012 for (i = 0; i < hist_data->n_sort_keys; i++) {
6013 sort_key = &hist_data->sort_keys[i];
6014 sort_key_test = &hist_data_test->sort_keys[i];
6015
6016 if (sort_key->field_idx != sort_key_test->field_idx ||
6017 sort_key->descending != sort_key_test->descending)
6018 return false;
6019 }
6020
6021 if (!ignore_filter && data->filter_str &&
6022 (strcmp(data->filter_str, data_test->filter_str) != 0))
6023 return false;
6024
6025 if (!actions_match(hist_data, hist_data_test))
6026 return false;
6027
6028 return true;
6029 }
6030
existing_hist_update_only(char * glob,struct event_trigger_data * data,struct trace_event_file * file)6031 static bool existing_hist_update_only(char *glob,
6032 struct event_trigger_data *data,
6033 struct trace_event_file *file)
6034 {
6035 struct hist_trigger_data *hist_data = data->private_data;
6036 struct event_trigger_data *test, *named_data = NULL;
6037 bool updated = false;
6038
6039 if (!hist_data->attrs->pause && !hist_data->attrs->cont &&
6040 !hist_data->attrs->clear)
6041 goto out;
6042
6043 if (hist_data->attrs->name) {
6044 named_data = find_named_trigger(hist_data->attrs->name);
6045 if (named_data) {
6046 if (!hist_trigger_match(data, named_data, named_data,
6047 true))
6048 goto out;
6049 }
6050 }
6051
6052 if (hist_data->attrs->name && !named_data)
6053 goto out;
6054
6055 list_for_each_entry(test, &file->triggers, list) {
6056 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6057 if (!hist_trigger_match(data, test, named_data, false))
6058 continue;
6059 if (hist_data->attrs->pause)
6060 test->paused = true;
6061 else if (hist_data->attrs->cont)
6062 test->paused = false;
6063 else if (hist_data->attrs->clear)
6064 hist_clear(test);
6065 updated = true;
6066 goto out;
6067 }
6068 }
6069 out:
6070 return updated;
6071 }
6072
hist_register_trigger(char * glob,struct event_trigger_data * data,struct trace_event_file * file)6073 static int hist_register_trigger(char *glob,
6074 struct event_trigger_data *data,
6075 struct trace_event_file *file)
6076 {
6077 struct hist_trigger_data *hist_data = data->private_data;
6078 struct event_trigger_data *test, *named_data = NULL;
6079 struct trace_array *tr = file->tr;
6080 int ret = 0;
6081
6082 if (hist_data->attrs->name) {
6083 named_data = find_named_trigger(hist_data->attrs->name);
6084 if (named_data) {
6085 if (!hist_trigger_match(data, named_data, named_data,
6086 true)) {
6087 hist_err(tr, HIST_ERR_NAMED_MISMATCH, errpos(hist_data->attrs->name));
6088 ret = -EINVAL;
6089 goto out;
6090 }
6091 }
6092 }
6093
6094 if (hist_data->attrs->name && !named_data)
6095 goto new;
6096
6097 lockdep_assert_held(&event_mutex);
6098
6099 list_for_each_entry(test, &file->triggers, list) {
6100 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6101 if (hist_trigger_match(data, test, named_data, false)) {
6102 hist_err(tr, HIST_ERR_TRIGGER_EEXIST, 0);
6103 ret = -EEXIST;
6104 goto out;
6105 }
6106 }
6107 }
6108 new:
6109 if (hist_data->attrs->cont || hist_data->attrs->clear) {
6110 hist_err(tr, HIST_ERR_TRIGGER_ENOENT_CLEAR, 0);
6111 ret = -ENOENT;
6112 goto out;
6113 }
6114
6115 if (hist_data->attrs->pause)
6116 data->paused = true;
6117
6118 if (named_data) {
6119 data->private_data = named_data->private_data;
6120 set_named_trigger_data(data, named_data);
6121 data->ops = &event_hist_trigger_named_ops;
6122 }
6123
6124 if (data->ops->init) {
6125 ret = data->ops->init(data);
6126 if (ret < 0)
6127 goto out;
6128 }
6129
6130 if (hist_data->enable_timestamps) {
6131 char *clock = hist_data->attrs->clock;
6132
6133 ret = tracing_set_clock(file->tr, hist_data->attrs->clock);
6134 if (ret) {
6135 hist_err(tr, HIST_ERR_SET_CLOCK_FAIL, errpos(clock));
6136 goto out;
6137 }
6138
6139 tracing_set_filter_buffering(file->tr, true);
6140 }
6141
6142 if (named_data)
6143 destroy_hist_data(hist_data);
6144 out:
6145 return ret;
6146 }
6147
hist_trigger_enable(struct event_trigger_data * data,struct trace_event_file * file)6148 static int hist_trigger_enable(struct event_trigger_data *data,
6149 struct trace_event_file *file)
6150 {
6151 int ret = 0;
6152
6153 list_add_tail_rcu(&data->list, &file->triggers);
6154
6155 update_cond_flag(file);
6156
6157 if (trace_event_trigger_enable_disable(file, 1) < 0) {
6158 list_del_rcu(&data->list);
6159 update_cond_flag(file);
6160 ret--;
6161 }
6162
6163 return ret;
6164 }
6165
have_hist_trigger_match(struct event_trigger_data * data,struct trace_event_file * file)6166 static bool have_hist_trigger_match(struct event_trigger_data *data,
6167 struct trace_event_file *file)
6168 {
6169 struct hist_trigger_data *hist_data = data->private_data;
6170 struct event_trigger_data *test, *named_data = NULL;
6171 bool match = false;
6172
6173 lockdep_assert_held(&event_mutex);
6174
6175 if (hist_data->attrs->name)
6176 named_data = find_named_trigger(hist_data->attrs->name);
6177
6178 list_for_each_entry(test, &file->triggers, list) {
6179 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6180 if (hist_trigger_match(data, test, named_data, false)) {
6181 match = true;
6182 break;
6183 }
6184 }
6185 }
6186
6187 return match;
6188 }
6189
hist_trigger_check_refs(struct event_trigger_data * data,struct trace_event_file * file)6190 static bool hist_trigger_check_refs(struct event_trigger_data *data,
6191 struct trace_event_file *file)
6192 {
6193 struct hist_trigger_data *hist_data = data->private_data;
6194 struct event_trigger_data *test, *named_data = NULL;
6195
6196 lockdep_assert_held(&event_mutex);
6197
6198 if (hist_data->attrs->name)
6199 named_data = find_named_trigger(hist_data->attrs->name);
6200
6201 list_for_each_entry(test, &file->triggers, list) {
6202 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6203 if (!hist_trigger_match(data, test, named_data, false))
6204 continue;
6205 hist_data = test->private_data;
6206 if (check_var_refs(hist_data))
6207 return true;
6208 break;
6209 }
6210 }
6211
6212 return false;
6213 }
6214
hist_unregister_trigger(char * glob,struct event_trigger_data * data,struct trace_event_file * file)6215 static void hist_unregister_trigger(char *glob,
6216 struct event_trigger_data *data,
6217 struct trace_event_file *file)
6218 {
6219 struct event_trigger_data *test = NULL, *iter, *named_data = NULL;
6220 struct hist_trigger_data *hist_data = data->private_data;
6221
6222 lockdep_assert_held(&event_mutex);
6223
6224 if (hist_data->attrs->name)
6225 named_data = find_named_trigger(hist_data->attrs->name);
6226
6227 list_for_each_entry(iter, &file->triggers, list) {
6228 if (iter->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6229 if (!hist_trigger_match(data, iter, named_data, false))
6230 continue;
6231 test = iter;
6232 list_del_rcu(&test->list);
6233 trace_event_trigger_enable_disable(file, 0);
6234 update_cond_flag(file);
6235 break;
6236 }
6237 }
6238
6239 if (test && test->ops->free)
6240 test->ops->free(test);
6241
6242 if (hist_data->enable_timestamps) {
6243 if (!hist_data->remove || test)
6244 tracing_set_filter_buffering(file->tr, false);
6245 }
6246 }
6247
hist_file_check_refs(struct trace_event_file * file)6248 static bool hist_file_check_refs(struct trace_event_file *file)
6249 {
6250 struct hist_trigger_data *hist_data;
6251 struct event_trigger_data *test;
6252
6253 lockdep_assert_held(&event_mutex);
6254
6255 list_for_each_entry(test, &file->triggers, list) {
6256 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6257 hist_data = test->private_data;
6258 if (check_var_refs(hist_data))
6259 return true;
6260 }
6261 }
6262
6263 return false;
6264 }
6265
hist_unreg_all(struct trace_event_file * file)6266 static void hist_unreg_all(struct trace_event_file *file)
6267 {
6268 struct event_trigger_data *test, *n;
6269 struct hist_trigger_data *hist_data;
6270 struct synth_event *se;
6271 const char *se_name;
6272
6273 lockdep_assert_held(&event_mutex);
6274
6275 if (hist_file_check_refs(file))
6276 return;
6277
6278 list_for_each_entry_safe(test, n, &file->triggers, list) {
6279 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6280 hist_data = test->private_data;
6281 list_del_rcu(&test->list);
6282 trace_event_trigger_enable_disable(file, 0);
6283
6284 se_name = trace_event_name(file->event_call);
6285 se = find_synth_event(se_name);
6286 if (se)
6287 se->ref--;
6288
6289 update_cond_flag(file);
6290 if (hist_data->enable_timestamps)
6291 tracing_set_filter_buffering(file->tr, false);
6292 if (test->ops->free)
6293 test->ops->free(test);
6294 }
6295 }
6296 }
6297
event_hist_trigger_parse(struct event_command * cmd_ops,struct trace_event_file * file,char * glob,char * cmd,char * param_and_filter)6298 static int event_hist_trigger_parse(struct event_command *cmd_ops,
6299 struct trace_event_file *file,
6300 char *glob, char *cmd,
6301 char *param_and_filter)
6302 {
6303 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
6304 struct event_trigger_data *trigger_data;
6305 struct hist_trigger_attrs *attrs;
6306 struct hist_trigger_data *hist_data;
6307 char *param, *filter, *p, *start;
6308 struct synth_event *se;
6309 const char *se_name;
6310 bool remove;
6311 int ret = 0;
6312
6313 lockdep_assert_held(&event_mutex);
6314
6315 if (WARN_ON(!glob))
6316 return -EINVAL;
6317
6318 if (glob[0]) {
6319 hist_err_clear();
6320 last_cmd_set(file, param_and_filter);
6321 }
6322
6323 remove = event_trigger_check_remove(glob);
6324
6325 if (event_trigger_empty_param(param_and_filter))
6326 return -EINVAL;
6327
6328 /*
6329 * separate the trigger from the filter (k:v [if filter])
6330 * allowing for whitespace in the trigger
6331 */
6332 p = param = param_and_filter;
6333 do {
6334 p = strstr(p, "if");
6335 if (!p)
6336 break;
6337 if (p == param_and_filter)
6338 return -EINVAL;
6339 if (*(p - 1) != ' ' && *(p - 1) != '\t') {
6340 p++;
6341 continue;
6342 }
6343 if (p >= param_and_filter + strlen(param_and_filter) - (sizeof("if") - 1) - 1)
6344 return -EINVAL;
6345 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') {
6346 p++;
6347 continue;
6348 }
6349 break;
6350 } while (1);
6351
6352 if (!p)
6353 filter = NULL;
6354 else {
6355 *(p - 1) = '\0';
6356 filter = strstrip(p);
6357 param = strstrip(param);
6358 }
6359
6360 /*
6361 * To simplify arithmetic expression parsing, replace occurrences of
6362 * '.sym-offset' modifier with '.symXoffset'
6363 */
6364 start = strstr(param, ".sym-offset");
6365 while (start) {
6366 *(start + 4) = 'X';
6367 start = strstr(start + 11, ".sym-offset");
6368 }
6369
6370 attrs = parse_hist_trigger_attrs(file->tr, param);
6371 if (IS_ERR(attrs))
6372 return PTR_ERR(attrs);
6373
6374 if (attrs->map_bits)
6375 hist_trigger_bits = attrs->map_bits;
6376
6377 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove);
6378 if (IS_ERR(hist_data)) {
6379 destroy_hist_trigger_attrs(attrs);
6380 return PTR_ERR(hist_data);
6381 }
6382
6383 trigger_data = event_trigger_alloc(cmd_ops, cmd, param, hist_data);
6384 if (!trigger_data) {
6385 ret = -ENOMEM;
6386 goto out_free;
6387 }
6388
6389 ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data);
6390 if (ret < 0)
6391 goto out_free;
6392
6393 if (remove) {
6394 if (!have_hist_trigger_match(trigger_data, file))
6395 goto out_free;
6396
6397 if (hist_trigger_check_refs(trigger_data, file)) {
6398 ret = -EBUSY;
6399 goto out_free;
6400 }
6401
6402 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
6403 se_name = trace_event_name(file->event_call);
6404 se = find_synth_event(se_name);
6405 if (se)
6406 se->ref--;
6407 ret = 0;
6408 goto out_free;
6409 }
6410
6411 if (existing_hist_update_only(glob, trigger_data, file))
6412 goto out_free;
6413
6414 ret = event_trigger_register(cmd_ops, file, glob, trigger_data);
6415 if (ret < 0)
6416 goto out_free;
6417
6418 if (get_named_trigger_data(trigger_data))
6419 goto enable;
6420
6421 if (has_hist_vars(hist_data))
6422 save_hist_vars(hist_data);
6423
6424 ret = create_actions(hist_data);
6425 if (ret)
6426 goto out_unreg;
6427
6428 ret = tracing_map_init(hist_data->map);
6429 if (ret)
6430 goto out_unreg;
6431 enable:
6432 ret = hist_trigger_enable(trigger_data, file);
6433 if (ret)
6434 goto out_unreg;
6435
6436 se_name = trace_event_name(file->event_call);
6437 se = find_synth_event(se_name);
6438 if (se)
6439 se->ref++;
6440 out:
6441 if (ret == 0)
6442 hist_err_clear();
6443
6444 return ret;
6445 out_unreg:
6446 event_trigger_unregister(cmd_ops, file, glob+1, trigger_data);
6447 out_free:
6448 event_trigger_reset_filter(cmd_ops, trigger_data);
6449
6450 remove_hist_vars(hist_data);
6451
6452 kfree(trigger_data);
6453
6454 destroy_hist_data(hist_data);
6455 goto out;
6456 }
6457
6458 static struct event_command trigger_hist_cmd = {
6459 .name = "hist",
6460 .trigger_type = ETT_EVENT_HIST,
6461 .flags = EVENT_CMD_FL_NEEDS_REC,
6462 .parse = event_hist_trigger_parse,
6463 .reg = hist_register_trigger,
6464 .unreg = hist_unregister_trigger,
6465 .unreg_all = hist_unreg_all,
6466 .get_trigger_ops = event_hist_get_trigger_ops,
6467 .set_filter = set_trigger_filter,
6468 };
6469
register_trigger_hist_cmd(void)6470 __init int register_trigger_hist_cmd(void)
6471 {
6472 int ret;
6473
6474 ret = register_event_command(&trigger_hist_cmd);
6475 WARN_ON(ret < 0);
6476
6477 return ret;
6478 }
6479
6480 static void
hist_enable_trigger(struct event_trigger_data * data,struct trace_buffer * buffer,void * rec,struct ring_buffer_event * event)6481 hist_enable_trigger(struct event_trigger_data *data,
6482 struct trace_buffer *buffer, void *rec,
6483 struct ring_buffer_event *event)
6484 {
6485 struct enable_trigger_data *enable_data = data->private_data;
6486 struct event_trigger_data *test;
6487
6488 list_for_each_entry_rcu(test, &enable_data->file->triggers, list,
6489 lockdep_is_held(&event_mutex)) {
6490 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
6491 if (enable_data->enable)
6492 test->paused = false;
6493 else
6494 test->paused = true;
6495 }
6496 }
6497 }
6498
6499 static void
hist_enable_count_trigger(struct event_trigger_data * data,struct trace_buffer * buffer,void * rec,struct ring_buffer_event * event)6500 hist_enable_count_trigger(struct event_trigger_data *data,
6501 struct trace_buffer *buffer, void *rec,
6502 struct ring_buffer_event *event)
6503 {
6504 if (!data->count)
6505 return;
6506
6507 if (data->count != -1)
6508 (data->count)--;
6509
6510 hist_enable_trigger(data, buffer, rec, event);
6511 }
6512
6513 static struct event_trigger_ops hist_enable_trigger_ops = {
6514 .trigger = hist_enable_trigger,
6515 .print = event_enable_trigger_print,
6516 .init = event_trigger_init,
6517 .free = event_enable_trigger_free,
6518 };
6519
6520 static struct event_trigger_ops hist_enable_count_trigger_ops = {
6521 .trigger = hist_enable_count_trigger,
6522 .print = event_enable_trigger_print,
6523 .init = event_trigger_init,
6524 .free = event_enable_trigger_free,
6525 };
6526
6527 static struct event_trigger_ops hist_disable_trigger_ops = {
6528 .trigger = hist_enable_trigger,
6529 .print = event_enable_trigger_print,
6530 .init = event_trigger_init,
6531 .free = event_enable_trigger_free,
6532 };
6533
6534 static struct event_trigger_ops hist_disable_count_trigger_ops = {
6535 .trigger = hist_enable_count_trigger,
6536 .print = event_enable_trigger_print,
6537 .init = event_trigger_init,
6538 .free = event_enable_trigger_free,
6539 };
6540
6541 static struct event_trigger_ops *
hist_enable_get_trigger_ops(char * cmd,char * param)6542 hist_enable_get_trigger_ops(char *cmd, char *param)
6543 {
6544 struct event_trigger_ops *ops;
6545 bool enable;
6546
6547 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0);
6548
6549 if (enable)
6550 ops = param ? &hist_enable_count_trigger_ops :
6551 &hist_enable_trigger_ops;
6552 else
6553 ops = param ? &hist_disable_count_trigger_ops :
6554 &hist_disable_trigger_ops;
6555
6556 return ops;
6557 }
6558
hist_enable_unreg_all(struct trace_event_file * file)6559 static void hist_enable_unreg_all(struct trace_event_file *file)
6560 {
6561 struct event_trigger_data *test, *n;
6562
6563 list_for_each_entry_safe(test, n, &file->triggers, list) {
6564 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) {
6565 list_del_rcu(&test->list);
6566 update_cond_flag(file);
6567 trace_event_trigger_enable_disable(file, 0);
6568 if (test->ops->free)
6569 test->ops->free(test);
6570 }
6571 }
6572 }
6573
6574 static struct event_command trigger_hist_enable_cmd = {
6575 .name = ENABLE_HIST_STR,
6576 .trigger_type = ETT_HIST_ENABLE,
6577 .parse = event_enable_trigger_parse,
6578 .reg = event_enable_register_trigger,
6579 .unreg = event_enable_unregister_trigger,
6580 .unreg_all = hist_enable_unreg_all,
6581 .get_trigger_ops = hist_enable_get_trigger_ops,
6582 .set_filter = set_trigger_filter,
6583 };
6584
6585 static struct event_command trigger_hist_disable_cmd = {
6586 .name = DISABLE_HIST_STR,
6587 .trigger_type = ETT_HIST_ENABLE,
6588 .parse = event_enable_trigger_parse,
6589 .reg = event_enable_register_trigger,
6590 .unreg = event_enable_unregister_trigger,
6591 .unreg_all = hist_enable_unreg_all,
6592 .get_trigger_ops = hist_enable_get_trigger_ops,
6593 .set_filter = set_trigger_filter,
6594 };
6595
unregister_trigger_hist_enable_disable_cmds(void)6596 static __init void unregister_trigger_hist_enable_disable_cmds(void)
6597 {
6598 unregister_event_command(&trigger_hist_enable_cmd);
6599 unregister_event_command(&trigger_hist_disable_cmd);
6600 }
6601
register_trigger_hist_enable_disable_cmds(void)6602 __init int register_trigger_hist_enable_disable_cmds(void)
6603 {
6604 int ret;
6605
6606 ret = register_event_command(&trigger_hist_enable_cmd);
6607 if (WARN_ON(ret < 0))
6608 return ret;
6609 ret = register_event_command(&trigger_hist_disable_cmd);
6610 if (WARN_ON(ret < 0))
6611 unregister_trigger_hist_enable_disable_cmds();
6612
6613 return ret;
6614 }
6615
