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