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/mutex.h>
11 #include <linux/slab.h>
12 #include <linux/stacktrace.h>
13 #include <linux/rculist.h>
14 #include <linux/tracefs.h>
15
16 #include "tracing_map.h"
17 #include "trace.h"
18
19 #define SYNTH_SYSTEM "synthetic"
20 #define SYNTH_FIELDS_MAX 16
21
22 #define STR_VAR_LEN_MAX 32 /* must be multiple of sizeof(u64) */
23
24 struct hist_field;
25
26 typedef u64 (*hist_field_fn_t) (struct hist_field *field,
27 struct tracing_map_elt *elt,
28 struct ring_buffer_event *rbe,
29 void *event);
30
31 #define HIST_FIELD_OPERANDS_MAX 2
32 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX)
33 #define HIST_ACTIONS_MAX 8
34
35 enum field_op_id {
36 FIELD_OP_NONE,
37 FIELD_OP_PLUS,
38 FIELD_OP_MINUS,
39 FIELD_OP_UNARY_MINUS,
40 };
41
42 struct hist_var {
43 char *name;
44 struct hist_trigger_data *hist_data;
45 unsigned int idx;
46 };
47
48 struct hist_field {
49 struct ftrace_event_field *field;
50 unsigned long flags;
51 hist_field_fn_t fn;
52 unsigned int size;
53 unsigned int offset;
54 unsigned int is_signed;
55 const char *type;
56 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX];
57 struct hist_trigger_data *hist_data;
58 struct hist_var var;
59 enum field_op_id operator;
60 char *system;
61 char *event_name;
62 char *name;
63 unsigned int var_idx;
64 unsigned int var_ref_idx;
65 bool read_once;
66 };
67
hist_field_none(struct hist_field * field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)68 static u64 hist_field_none(struct hist_field *field,
69 struct tracing_map_elt *elt,
70 struct ring_buffer_event *rbe,
71 void *event)
72 {
73 return 0;
74 }
75
hist_field_counter(struct hist_field * field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)76 static u64 hist_field_counter(struct hist_field *field,
77 struct tracing_map_elt *elt,
78 struct ring_buffer_event *rbe,
79 void *event)
80 {
81 return 1;
82 }
83
hist_field_string(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)84 static u64 hist_field_string(struct hist_field *hist_field,
85 struct tracing_map_elt *elt,
86 struct ring_buffer_event *rbe,
87 void *event)
88 {
89 char *addr = (char *)(event + hist_field->field->offset);
90
91 return (u64)(unsigned long)addr;
92 }
93
hist_field_dynstring(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)94 static u64 hist_field_dynstring(struct hist_field *hist_field,
95 struct tracing_map_elt *elt,
96 struct ring_buffer_event *rbe,
97 void *event)
98 {
99 u32 str_item = *(u32 *)(event + hist_field->field->offset);
100 int str_loc = str_item & 0xffff;
101 char *addr = (char *)(event + str_loc);
102
103 return (u64)(unsigned long)addr;
104 }
105
hist_field_pstring(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)106 static u64 hist_field_pstring(struct hist_field *hist_field,
107 struct tracing_map_elt *elt,
108 struct ring_buffer_event *rbe,
109 void *event)
110 {
111 char **addr = (char **)(event + hist_field->field->offset);
112
113 return (u64)(unsigned long)*addr;
114 }
115
hist_field_log2(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)116 static u64 hist_field_log2(struct hist_field *hist_field,
117 struct tracing_map_elt *elt,
118 struct ring_buffer_event *rbe,
119 void *event)
120 {
121 struct hist_field *operand = hist_field->operands[0];
122
123 u64 val = operand->fn(operand, elt, rbe, event);
124
125 return (u64) ilog2(roundup_pow_of_two(val));
126 }
127
hist_field_plus(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)128 static u64 hist_field_plus(struct hist_field *hist_field,
129 struct tracing_map_elt *elt,
130 struct ring_buffer_event *rbe,
131 void *event)
132 {
133 struct hist_field *operand1 = hist_field->operands[0];
134 struct hist_field *operand2 = hist_field->operands[1];
135
136 u64 val1 = operand1->fn(operand1, elt, rbe, event);
137 u64 val2 = operand2->fn(operand2, elt, rbe, event);
138
139 return val1 + val2;
140 }
141
hist_field_minus(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)142 static u64 hist_field_minus(struct hist_field *hist_field,
143 struct tracing_map_elt *elt,
144 struct ring_buffer_event *rbe,
145 void *event)
146 {
147 struct hist_field *operand1 = hist_field->operands[0];
148 struct hist_field *operand2 = hist_field->operands[1];
149
150 u64 val1 = operand1->fn(operand1, elt, rbe, event);
151 u64 val2 = operand2->fn(operand2, elt, rbe, event);
152
153 return val1 - val2;
154 }
155
hist_field_unary_minus(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)156 static u64 hist_field_unary_minus(struct hist_field *hist_field,
157 struct tracing_map_elt *elt,
158 struct ring_buffer_event *rbe,
159 void *event)
160 {
161 struct hist_field *operand = hist_field->operands[0];
162
163 s64 sval = (s64)operand->fn(operand, elt, rbe, event);
164 u64 val = (u64)-sval;
165
166 return val;
167 }
168
169 #define DEFINE_HIST_FIELD_FN(type) \
170 static u64 hist_field_##type(struct hist_field *hist_field, \
171 struct tracing_map_elt *elt, \
172 struct ring_buffer_event *rbe, \
173 void *event) \
174 { \
175 type *addr = (type *)(event + hist_field->field->offset); \
176 \
177 return (u64)(unsigned long)*addr; \
178 }
179
180 DEFINE_HIST_FIELD_FN(s64);
181 DEFINE_HIST_FIELD_FN(u64);
182 DEFINE_HIST_FIELD_FN(s32);
183 DEFINE_HIST_FIELD_FN(u32);
184 DEFINE_HIST_FIELD_FN(s16);
185 DEFINE_HIST_FIELD_FN(u16);
186 DEFINE_HIST_FIELD_FN(s8);
187 DEFINE_HIST_FIELD_FN(u8);
188
189 #define for_each_hist_field(i, hist_data) \
190 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++)
191
192 #define for_each_hist_val_field(i, hist_data) \
193 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++)
194
195 #define for_each_hist_key_field(i, hist_data) \
196 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++)
197
198 #define HIST_STACKTRACE_DEPTH 16
199 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
200 #define HIST_STACKTRACE_SKIP 5
201
202 #define HITCOUNT_IDX 0
203 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE)
204
205 enum hist_field_flags {
206 HIST_FIELD_FL_HITCOUNT = 1 << 0,
207 HIST_FIELD_FL_KEY = 1 << 1,
208 HIST_FIELD_FL_STRING = 1 << 2,
209 HIST_FIELD_FL_HEX = 1 << 3,
210 HIST_FIELD_FL_SYM = 1 << 4,
211 HIST_FIELD_FL_SYM_OFFSET = 1 << 5,
212 HIST_FIELD_FL_EXECNAME = 1 << 6,
213 HIST_FIELD_FL_SYSCALL = 1 << 7,
214 HIST_FIELD_FL_STACKTRACE = 1 << 8,
215 HIST_FIELD_FL_LOG2 = 1 << 9,
216 HIST_FIELD_FL_TIMESTAMP = 1 << 10,
217 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11,
218 HIST_FIELD_FL_VAR = 1 << 12,
219 HIST_FIELD_FL_EXPR = 1 << 13,
220 HIST_FIELD_FL_VAR_REF = 1 << 14,
221 HIST_FIELD_FL_CPU = 1 << 15,
222 HIST_FIELD_FL_ALIAS = 1 << 16,
223 };
224
225 struct var_defs {
226 unsigned int n_vars;
227 char *name[TRACING_MAP_VARS_MAX];
228 char *expr[TRACING_MAP_VARS_MAX];
229 };
230
231 struct hist_trigger_attrs {
232 char *keys_str;
233 char *vals_str;
234 char *sort_key_str;
235 char *name;
236 char *clock;
237 bool pause;
238 bool cont;
239 bool clear;
240 bool ts_in_usecs;
241 unsigned int map_bits;
242
243 char *assignment_str[TRACING_MAP_VARS_MAX];
244 unsigned int n_assignments;
245
246 char *action_str[HIST_ACTIONS_MAX];
247 unsigned int n_actions;
248
249 struct var_defs var_defs;
250 };
251
252 struct field_var {
253 struct hist_field *var;
254 struct hist_field *val;
255 };
256
257 struct field_var_hist {
258 struct hist_trigger_data *hist_data;
259 char *cmd;
260 };
261
262 struct hist_trigger_data {
263 struct hist_field *fields[HIST_FIELDS_MAX];
264 unsigned int n_vals;
265 unsigned int n_keys;
266 unsigned int n_fields;
267 unsigned int n_vars;
268 unsigned int key_size;
269 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX];
270 unsigned int n_sort_keys;
271 struct trace_event_file *event_file;
272 struct hist_trigger_attrs *attrs;
273 struct tracing_map *map;
274 bool enable_timestamps;
275 bool remove;
276 struct hist_field *var_refs[TRACING_MAP_VARS_MAX];
277 unsigned int n_var_refs;
278
279 struct action_data *actions[HIST_ACTIONS_MAX];
280 unsigned int n_actions;
281
282 struct hist_field *synth_var_refs[SYNTH_FIELDS_MAX];
283 unsigned int n_synth_var_refs;
284 struct field_var *field_vars[SYNTH_FIELDS_MAX];
285 unsigned int n_field_vars;
286 unsigned int n_field_var_str;
287 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX];
288 unsigned int n_field_var_hists;
289
290 struct field_var *max_vars[SYNTH_FIELDS_MAX];
291 unsigned int n_max_vars;
292 unsigned int n_max_var_str;
293 };
294
295 struct synth_field {
296 char *type;
297 char *name;
298 size_t size;
299 bool is_signed;
300 bool is_string;
301 };
302
303 struct synth_event {
304 struct list_head list;
305 int ref;
306 char *name;
307 struct synth_field **fields;
308 unsigned int n_fields;
309 unsigned int n_u64;
310 struct trace_event_class class;
311 struct trace_event_call call;
312 struct tracepoint *tp;
313 };
314
315 struct action_data;
316
317 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data,
318 struct tracing_map_elt *elt, void *rec,
319 struct ring_buffer_event *rbe,
320 struct action_data *data, u64 *var_ref_vals);
321
322 struct action_data {
323 action_fn_t fn;
324 unsigned int n_params;
325 char *params[SYNTH_FIELDS_MAX];
326
327 union {
328 struct {
329 unsigned int var_ref_idx;
330 char *match_event;
331 char *match_event_system;
332 char *synth_event_name;
333 struct synth_event *synth_event;
334 } onmatch;
335
336 struct {
337 char *var_str;
338 char *fn_name;
339 unsigned int max_var_ref_idx;
340 struct hist_field *max_var;
341 struct hist_field *var;
342 } onmax;
343 };
344 };
345
346
347 static char last_hist_cmd[MAX_FILTER_STR_VAL];
348 static char hist_err_str[MAX_FILTER_STR_VAL];
349
last_cmd_set(char * str)350 static void last_cmd_set(char *str)
351 {
352 if (!str)
353 return;
354
355 strncpy(last_hist_cmd, str, MAX_FILTER_STR_VAL - 1);
356 }
357
hist_err(char * str,char * var)358 static void hist_err(char *str, char *var)
359 {
360 int maxlen = MAX_FILTER_STR_VAL - 1;
361
362 if (!str)
363 return;
364
365 if (strlen(hist_err_str))
366 return;
367
368 if (!var)
369 var = "";
370
371 if (strlen(hist_err_str) + strlen(str) + strlen(var) > maxlen)
372 return;
373
374 strcat(hist_err_str, str);
375 strcat(hist_err_str, var);
376 }
377
hist_err_event(char * str,char * system,char * event,char * var)378 static void hist_err_event(char *str, char *system, char *event, char *var)
379 {
380 char err[MAX_FILTER_STR_VAL];
381
382 if (system && var)
383 snprintf(err, MAX_FILTER_STR_VAL, "%s.%s.%s", system, event, var);
384 else if (system)
385 snprintf(err, MAX_FILTER_STR_VAL, "%s.%s", system, event);
386 else
387 strscpy(err, var, MAX_FILTER_STR_VAL);
388
389 hist_err(str, err);
390 }
391
hist_err_clear(void)392 static void hist_err_clear(void)
393 {
394 hist_err_str[0] = '\0';
395 }
396
have_hist_err(void)397 static bool have_hist_err(void)
398 {
399 if (strlen(hist_err_str))
400 return true;
401
402 return false;
403 }
404
405 static LIST_HEAD(synth_event_list);
406 static DEFINE_MUTEX(synth_event_mutex);
407
408 struct synth_trace_event {
409 struct trace_entry ent;
410 u64 fields[];
411 };
412
synth_event_define_fields(struct trace_event_call * call)413 static int synth_event_define_fields(struct trace_event_call *call)
414 {
415 struct synth_trace_event trace;
416 int offset = offsetof(typeof(trace), fields);
417 struct synth_event *event = call->data;
418 unsigned int i, size, n_u64;
419 char *name, *type;
420 bool is_signed;
421 int ret = 0;
422
423 for (i = 0, n_u64 = 0; i < event->n_fields; i++) {
424 size = event->fields[i]->size;
425 is_signed = event->fields[i]->is_signed;
426 type = event->fields[i]->type;
427 name = event->fields[i]->name;
428 ret = trace_define_field(call, type, name, offset, size,
429 is_signed, FILTER_OTHER);
430 if (ret)
431 break;
432
433 if (event->fields[i]->is_string) {
434 offset += STR_VAR_LEN_MAX;
435 n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
436 } else {
437 offset += sizeof(u64);
438 n_u64++;
439 }
440 }
441
442 event->n_u64 = n_u64;
443
444 return ret;
445 }
446
synth_field_signed(char * type)447 static bool synth_field_signed(char *type)
448 {
449 if (strncmp(type, "u", 1) == 0)
450 return false;
451
452 return true;
453 }
454
synth_field_is_string(char * type)455 static int synth_field_is_string(char *type)
456 {
457 if (strstr(type, "char[") != NULL)
458 return true;
459
460 return false;
461 }
462
synth_field_string_size(char * type)463 static int synth_field_string_size(char *type)
464 {
465 char buf[4], *end, *start;
466 unsigned int len;
467 int size, err;
468
469 start = strstr(type, "char[");
470 if (start == NULL)
471 return -EINVAL;
472 start += strlen("char[");
473
474 end = strchr(type, ']');
475 if (!end || end < start)
476 return -EINVAL;
477
478 len = end - start;
479 if (len > 3)
480 return -EINVAL;
481
482 strncpy(buf, start, len);
483 buf[len] = '\0';
484
485 err = kstrtouint(buf, 0, &size);
486 if (err)
487 return err;
488
489 if (size > STR_VAR_LEN_MAX)
490 return -EINVAL;
491
492 return size;
493 }
494
synth_field_size(char * type)495 static int synth_field_size(char *type)
496 {
497 int size = 0;
498
499 if (strcmp(type, "s64") == 0)
500 size = sizeof(s64);
501 else if (strcmp(type, "u64") == 0)
502 size = sizeof(u64);
503 else if (strcmp(type, "s32") == 0)
504 size = sizeof(s32);
505 else if (strcmp(type, "u32") == 0)
506 size = sizeof(u32);
507 else if (strcmp(type, "s16") == 0)
508 size = sizeof(s16);
509 else if (strcmp(type, "u16") == 0)
510 size = sizeof(u16);
511 else if (strcmp(type, "s8") == 0)
512 size = sizeof(s8);
513 else if (strcmp(type, "u8") == 0)
514 size = sizeof(u8);
515 else if (strcmp(type, "char") == 0)
516 size = sizeof(char);
517 else if (strcmp(type, "unsigned char") == 0)
518 size = sizeof(unsigned char);
519 else if (strcmp(type, "int") == 0)
520 size = sizeof(int);
521 else if (strcmp(type, "unsigned int") == 0)
522 size = sizeof(unsigned int);
523 else if (strcmp(type, "long") == 0)
524 size = sizeof(long);
525 else if (strcmp(type, "unsigned long") == 0)
526 size = sizeof(unsigned long);
527 else if (strcmp(type, "pid_t") == 0)
528 size = sizeof(pid_t);
529 else if (synth_field_is_string(type))
530 size = synth_field_string_size(type);
531
532 return size;
533 }
534
synth_field_fmt(char * type)535 static const char *synth_field_fmt(char *type)
536 {
537 const char *fmt = "%llu";
538
539 if (strcmp(type, "s64") == 0)
540 fmt = "%lld";
541 else if (strcmp(type, "u64") == 0)
542 fmt = "%llu";
543 else if (strcmp(type, "s32") == 0)
544 fmt = "%d";
545 else if (strcmp(type, "u32") == 0)
546 fmt = "%u";
547 else if (strcmp(type, "s16") == 0)
548 fmt = "%d";
549 else if (strcmp(type, "u16") == 0)
550 fmt = "%u";
551 else if (strcmp(type, "s8") == 0)
552 fmt = "%d";
553 else if (strcmp(type, "u8") == 0)
554 fmt = "%u";
555 else if (strcmp(type, "char") == 0)
556 fmt = "%d";
557 else if (strcmp(type, "unsigned char") == 0)
558 fmt = "%u";
559 else if (strcmp(type, "int") == 0)
560 fmt = "%d";
561 else if (strcmp(type, "unsigned int") == 0)
562 fmt = "%u";
563 else if (strcmp(type, "long") == 0)
564 fmt = "%ld";
565 else if (strcmp(type, "unsigned long") == 0)
566 fmt = "%lu";
567 else if (strcmp(type, "pid_t") == 0)
568 fmt = "%d";
569 else if (synth_field_is_string(type))
570 fmt = "%s";
571
572 return fmt;
573 }
574
print_synth_event(struct trace_iterator * iter,int flags,struct trace_event * event)575 static enum print_line_t print_synth_event(struct trace_iterator *iter,
576 int flags,
577 struct trace_event *event)
578 {
579 struct trace_array *tr = iter->tr;
580 struct trace_seq *s = &iter->seq;
581 struct synth_trace_event *entry;
582 struct synth_event *se;
583 unsigned int i, n_u64;
584 char print_fmt[32];
585 const char *fmt;
586
587 entry = (struct synth_trace_event *)iter->ent;
588 se = container_of(event, struct synth_event, call.event);
589
590 trace_seq_printf(s, "%s: ", se->name);
591
592 for (i = 0, n_u64 = 0; i < se->n_fields; i++) {
593 if (trace_seq_has_overflowed(s))
594 goto end;
595
596 fmt = synth_field_fmt(se->fields[i]->type);
597
598 /* parameter types */
599 if (tr->trace_flags & TRACE_ITER_VERBOSE)
600 trace_seq_printf(s, "%s ", fmt);
601
602 snprintf(print_fmt, sizeof(print_fmt), "%%s=%s%%s", fmt);
603
604 /* parameter values */
605 if (se->fields[i]->is_string) {
606 trace_seq_printf(s, print_fmt, se->fields[i]->name,
607 (char *)&entry->fields[n_u64],
608 i == se->n_fields - 1 ? "" : " ");
609 n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
610 } else {
611 trace_seq_printf(s, print_fmt, se->fields[i]->name,
612 entry->fields[n_u64],
613 i == se->n_fields - 1 ? "" : " ");
614 n_u64++;
615 }
616 }
617 end:
618 trace_seq_putc(s, '\n');
619
620 return trace_handle_return(s);
621 }
622
623 static struct trace_event_functions synth_event_funcs = {
624 .trace = print_synth_event
625 };
626
trace_event_raw_event_synth(void * __data,u64 * var_ref_vals,unsigned int var_ref_idx)627 static notrace void trace_event_raw_event_synth(void *__data,
628 u64 *var_ref_vals,
629 unsigned int var_ref_idx)
630 {
631 struct trace_event_file *trace_file = __data;
632 struct synth_trace_event *entry;
633 struct trace_event_buffer fbuffer;
634 struct ring_buffer *buffer;
635 struct synth_event *event;
636 unsigned int i, n_u64;
637 int fields_size = 0;
638
639 event = trace_file->event_call->data;
640
641 if (trace_trigger_soft_disabled(trace_file))
642 return;
643
644 fields_size = event->n_u64 * sizeof(u64);
645
646 /*
647 * Avoid ring buffer recursion detection, as this event
648 * is being performed within another event.
649 */
650 buffer = trace_file->tr->trace_buffer.buffer;
651 ring_buffer_nest_start(buffer);
652
653 entry = trace_event_buffer_reserve(&fbuffer, trace_file,
654 sizeof(*entry) + fields_size);
655 if (!entry)
656 goto out;
657
658 for (i = 0, n_u64 = 0; i < event->n_fields; i++) {
659 if (event->fields[i]->is_string) {
660 char *str_val = (char *)(long)var_ref_vals[var_ref_idx + i];
661 char *str_field = (char *)&entry->fields[n_u64];
662
663 strscpy(str_field, str_val, STR_VAR_LEN_MAX);
664 n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
665 } else {
666 entry->fields[n_u64] = var_ref_vals[var_ref_idx + i];
667 n_u64++;
668 }
669 }
670
671 trace_event_buffer_commit(&fbuffer);
672 out:
673 ring_buffer_nest_end(buffer);
674 }
675
free_synth_event_print_fmt(struct trace_event_call * call)676 static void free_synth_event_print_fmt(struct trace_event_call *call)
677 {
678 if (call) {
679 kfree(call->print_fmt);
680 call->print_fmt = NULL;
681 }
682 }
683
__set_synth_event_print_fmt(struct synth_event * event,char * buf,int len)684 static int __set_synth_event_print_fmt(struct synth_event *event,
685 char *buf, int len)
686 {
687 const char *fmt;
688 int pos = 0;
689 int i;
690
691 /* When len=0, we just calculate the needed length */
692 #define LEN_OR_ZERO (len ? len - pos : 0)
693
694 pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
695 for (i = 0; i < event->n_fields; i++) {
696 fmt = synth_field_fmt(event->fields[i]->type);
697 pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s%s",
698 event->fields[i]->name, fmt,
699 i == event->n_fields - 1 ? "" : ", ");
700 }
701 pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
702
703 for (i = 0; i < event->n_fields; i++) {
704 pos += snprintf(buf + pos, LEN_OR_ZERO,
705 ", REC->%s", event->fields[i]->name);
706 }
707
708 #undef LEN_OR_ZERO
709
710 /* return the length of print_fmt */
711 return pos;
712 }
713
set_synth_event_print_fmt(struct trace_event_call * call)714 static int set_synth_event_print_fmt(struct trace_event_call *call)
715 {
716 struct synth_event *event = call->data;
717 char *print_fmt;
718 int len;
719
720 /* First: called with 0 length to calculate the needed length */
721 len = __set_synth_event_print_fmt(event, NULL, 0);
722
723 print_fmt = kmalloc(len + 1, GFP_KERNEL);
724 if (!print_fmt)
725 return -ENOMEM;
726
727 /* Second: actually write the @print_fmt */
728 __set_synth_event_print_fmt(event, print_fmt, len + 1);
729 call->print_fmt = print_fmt;
730
731 return 0;
732 }
733
free_synth_field(struct synth_field * field)734 static void free_synth_field(struct synth_field *field)
735 {
736 kfree(field->type);
737 kfree(field->name);
738 kfree(field);
739 }
740
parse_synth_field(int argc,char ** argv,int * consumed)741 static struct synth_field *parse_synth_field(int argc, char **argv,
742 int *consumed)
743 {
744 struct synth_field *field;
745 const char *prefix = NULL;
746 char *field_type = argv[0], *field_name;
747 int len, ret = 0;
748 char *array;
749
750 if (field_type[0] == ';')
751 field_type++;
752
753 if (!strcmp(field_type, "unsigned")) {
754 if (argc < 3)
755 return ERR_PTR(-EINVAL);
756 prefix = "unsigned ";
757 field_type = argv[1];
758 field_name = argv[2];
759 *consumed = 3;
760 } else {
761 field_name = argv[1];
762 *consumed = 2;
763 }
764
765 len = strlen(field_name);
766 if (field_name[len - 1] == ';')
767 field_name[len - 1] = '\0';
768
769 field = kzalloc(sizeof(*field), GFP_KERNEL);
770 if (!field)
771 return ERR_PTR(-ENOMEM);
772
773 len = strlen(field_type) + 1;
774 array = strchr(field_name, '[');
775 if (array)
776 len += strlen(array);
777 if (prefix)
778 len += strlen(prefix);
779 field->type = kzalloc(len, GFP_KERNEL);
780 if (!field->type) {
781 ret = -ENOMEM;
782 goto free;
783 }
784 if (prefix)
785 strcat(field->type, prefix);
786 strcat(field->type, field_type);
787 if (array) {
788 strcat(field->type, array);
789 *array = '\0';
790 }
791
792 field->size = synth_field_size(field->type);
793 if (!field->size) {
794 ret = -EINVAL;
795 goto free;
796 }
797
798 if (synth_field_is_string(field->type))
799 field->is_string = true;
800
801 field->is_signed = synth_field_signed(field->type);
802
803 field->name = kstrdup(field_name, GFP_KERNEL);
804 if (!field->name) {
805 ret = -ENOMEM;
806 goto free;
807 }
808 out:
809 return field;
810 free:
811 free_synth_field(field);
812 field = ERR_PTR(ret);
813 goto out;
814 }
815
free_synth_tracepoint(struct tracepoint * tp)816 static void free_synth_tracepoint(struct tracepoint *tp)
817 {
818 if (!tp)
819 return;
820
821 kfree(tp->name);
822 kfree(tp);
823 }
824
alloc_synth_tracepoint(char * name)825 static struct tracepoint *alloc_synth_tracepoint(char *name)
826 {
827 struct tracepoint *tp;
828
829 tp = kzalloc(sizeof(*tp), GFP_KERNEL);
830 if (!tp)
831 return ERR_PTR(-ENOMEM);
832
833 tp->name = kstrdup(name, GFP_KERNEL);
834 if (!tp->name) {
835 kfree(tp);
836 return ERR_PTR(-ENOMEM);
837 }
838
839 return tp;
840 }
841
842 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals,
843 unsigned int var_ref_idx);
844
trace_synth(struct synth_event * event,u64 * var_ref_vals,unsigned int var_ref_idx)845 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals,
846 unsigned int var_ref_idx)
847 {
848 struct tracepoint *tp = event->tp;
849
850 if (unlikely(atomic_read(&tp->key.enabled) > 0)) {
851 struct tracepoint_func *probe_func_ptr;
852 synth_probe_func_t probe_func;
853 void *__data;
854
855 if (!(cpu_online(raw_smp_processor_id())))
856 return;
857
858 probe_func_ptr = rcu_dereference_sched((tp)->funcs);
859 if (probe_func_ptr) {
860 do {
861 probe_func = probe_func_ptr->func;
862 __data = probe_func_ptr->data;
863 probe_func(__data, var_ref_vals, var_ref_idx);
864 } while ((++probe_func_ptr)->func);
865 }
866 }
867 }
868
find_synth_event(const char * name)869 static struct synth_event *find_synth_event(const char *name)
870 {
871 struct synth_event *event;
872
873 list_for_each_entry(event, &synth_event_list, list) {
874 if (strcmp(event->name, name) == 0)
875 return event;
876 }
877
878 return NULL;
879 }
880
register_synth_event(struct synth_event * event)881 static int register_synth_event(struct synth_event *event)
882 {
883 struct trace_event_call *call = &event->call;
884 int ret = 0;
885
886 event->call.class = &event->class;
887 event->class.system = kstrdup(SYNTH_SYSTEM, GFP_KERNEL);
888 if (!event->class.system) {
889 ret = -ENOMEM;
890 goto out;
891 }
892
893 event->tp = alloc_synth_tracepoint(event->name);
894 if (IS_ERR(event->tp)) {
895 ret = PTR_ERR(event->tp);
896 event->tp = NULL;
897 goto out;
898 }
899
900 INIT_LIST_HEAD(&call->class->fields);
901 call->event.funcs = &synth_event_funcs;
902 call->class->define_fields = synth_event_define_fields;
903
904 ret = register_trace_event(&call->event);
905 if (!ret) {
906 ret = -ENODEV;
907 goto out;
908 }
909 call->flags = TRACE_EVENT_FL_TRACEPOINT;
910 call->class->reg = trace_event_reg;
911 call->class->probe = trace_event_raw_event_synth;
912 call->data = event;
913 call->tp = event->tp;
914
915 ret = trace_add_event_call(call);
916 if (ret) {
917 pr_warn("Failed to register synthetic event: %s\n",
918 trace_event_name(call));
919 goto err;
920 }
921
922 ret = set_synth_event_print_fmt(call);
923 if (ret < 0) {
924 trace_remove_event_call(call);
925 goto err;
926 }
927 out:
928 return ret;
929 err:
930 unregister_trace_event(&call->event);
931 goto out;
932 }
933
unregister_synth_event(struct synth_event * event)934 static int unregister_synth_event(struct synth_event *event)
935 {
936 struct trace_event_call *call = &event->call;
937 int ret;
938
939 ret = trace_remove_event_call(call);
940
941 return ret;
942 }
943
free_synth_event(struct synth_event * event)944 static void free_synth_event(struct synth_event *event)
945 {
946 unsigned int i;
947
948 if (!event)
949 return;
950
951 for (i = 0; i < event->n_fields; i++)
952 free_synth_field(event->fields[i]);
953
954 kfree(event->fields);
955 kfree(event->name);
956 kfree(event->class.system);
957 free_synth_tracepoint(event->tp);
958 free_synth_event_print_fmt(&event->call);
959 kfree(event);
960 }
961
alloc_synth_event(char * event_name,int n_fields,struct synth_field ** fields)962 static struct synth_event *alloc_synth_event(char *event_name, int n_fields,
963 struct synth_field **fields)
964 {
965 struct synth_event *event;
966 unsigned int i;
967
968 event = kzalloc(sizeof(*event), GFP_KERNEL);
969 if (!event) {
970 event = ERR_PTR(-ENOMEM);
971 goto out;
972 }
973
974 event->name = kstrdup(event_name, GFP_KERNEL);
975 if (!event->name) {
976 kfree(event);
977 event = ERR_PTR(-ENOMEM);
978 goto out;
979 }
980
981 event->fields = kcalloc(n_fields, sizeof(*event->fields), GFP_KERNEL);
982 if (!event->fields) {
983 free_synth_event(event);
984 event = ERR_PTR(-ENOMEM);
985 goto out;
986 }
987
988 for (i = 0; i < n_fields; i++)
989 event->fields[i] = fields[i];
990
991 event->n_fields = n_fields;
992 out:
993 return event;
994 }
995
action_trace(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,struct action_data * data,u64 * var_ref_vals)996 static void action_trace(struct hist_trigger_data *hist_data,
997 struct tracing_map_elt *elt, void *rec,
998 struct ring_buffer_event *rbe,
999 struct action_data *data, u64 *var_ref_vals)
1000 {
1001 struct synth_event *event = data->onmatch.synth_event;
1002
1003 trace_synth(event, var_ref_vals, data->onmatch.var_ref_idx);
1004 }
1005
1006 struct hist_var_data {
1007 struct list_head list;
1008 struct hist_trigger_data *hist_data;
1009 };
1010
add_or_delete_synth_event(struct synth_event * event,int delete)1011 static void add_or_delete_synth_event(struct synth_event *event, int delete)
1012 {
1013 if (delete)
1014 free_synth_event(event);
1015 else {
1016 mutex_lock(&synth_event_mutex);
1017 if (!find_synth_event(event->name))
1018 list_add(&event->list, &synth_event_list);
1019 else
1020 free_synth_event(event);
1021 mutex_unlock(&synth_event_mutex);
1022 }
1023 }
1024
create_synth_event(int argc,char ** argv)1025 static int create_synth_event(int argc, char **argv)
1026 {
1027 struct synth_field *field, *fields[SYNTH_FIELDS_MAX];
1028 struct synth_event *event = NULL;
1029 bool delete_event = false;
1030 int i, consumed = 0, n_fields = 0, ret = 0;
1031 char *name;
1032
1033 mutex_lock(&synth_event_mutex);
1034
1035 /*
1036 * Argument syntax:
1037 * - Add synthetic event: <event_name> field[;field] ...
1038 * - Remove synthetic event: !<event_name> field[;field] ...
1039 * where 'field' = type field_name
1040 */
1041 if (argc < 1) {
1042 ret = -EINVAL;
1043 goto out;
1044 }
1045
1046 name = argv[0];
1047 if (name[0] == '!') {
1048 delete_event = true;
1049 name++;
1050 }
1051
1052 event = find_synth_event(name);
1053 if (event) {
1054 if (delete_event) {
1055 if (event->ref) {
1056 event = NULL;
1057 ret = -EBUSY;
1058 goto out;
1059 }
1060 list_del(&event->list);
1061 goto out;
1062 }
1063 event = NULL;
1064 ret = -EEXIST;
1065 goto out;
1066 } else if (delete_event)
1067 goto out;
1068
1069 if (argc < 2) {
1070 ret = -EINVAL;
1071 goto out;
1072 }
1073
1074 for (i = 1; i < argc - 1; i++) {
1075 if (strcmp(argv[i], ";") == 0)
1076 continue;
1077 if (n_fields == SYNTH_FIELDS_MAX) {
1078 ret = -EINVAL;
1079 goto err;
1080 }
1081
1082 field = parse_synth_field(argc - i, &argv[i], &consumed);
1083 if (IS_ERR(field)) {
1084 ret = PTR_ERR(field);
1085 goto err;
1086 }
1087 fields[n_fields++] = field;
1088 i += consumed - 1;
1089 }
1090
1091 if (i < argc && strcmp(argv[i], ";") != 0) {
1092 ret = -EINVAL;
1093 goto err;
1094 }
1095
1096 event = alloc_synth_event(name, n_fields, fields);
1097 if (IS_ERR(event)) {
1098 ret = PTR_ERR(event);
1099 event = NULL;
1100 goto err;
1101 }
1102 out:
1103 mutex_unlock(&synth_event_mutex);
1104
1105 if (event) {
1106 if (delete_event) {
1107 ret = unregister_synth_event(event);
1108 add_or_delete_synth_event(event, !ret);
1109 } else {
1110 ret = register_synth_event(event);
1111 add_or_delete_synth_event(event, ret);
1112 }
1113 }
1114
1115 return ret;
1116 err:
1117 mutex_unlock(&synth_event_mutex);
1118
1119 for (i = 0; i < n_fields; i++)
1120 free_synth_field(fields[i]);
1121 free_synth_event(event);
1122
1123 return ret;
1124 }
1125
release_all_synth_events(void)1126 static int release_all_synth_events(void)
1127 {
1128 struct list_head release_events;
1129 struct synth_event *event, *e;
1130 int ret = 0;
1131
1132 INIT_LIST_HEAD(&release_events);
1133
1134 mutex_lock(&synth_event_mutex);
1135
1136 list_for_each_entry(event, &synth_event_list, list) {
1137 if (event->ref) {
1138 mutex_unlock(&synth_event_mutex);
1139 return -EBUSY;
1140 }
1141 }
1142
1143 list_splice_init(&event->list, &release_events);
1144
1145 mutex_unlock(&synth_event_mutex);
1146
1147 list_for_each_entry_safe(event, e, &release_events, list) {
1148 list_del(&event->list);
1149
1150 ret = unregister_synth_event(event);
1151 add_or_delete_synth_event(event, !ret);
1152 }
1153
1154 return ret;
1155 }
1156
1157
synth_events_seq_start(struct seq_file * m,loff_t * pos)1158 static void *synth_events_seq_start(struct seq_file *m, loff_t *pos)
1159 {
1160 mutex_lock(&synth_event_mutex);
1161
1162 return seq_list_start(&synth_event_list, *pos);
1163 }
1164
synth_events_seq_next(struct seq_file * m,void * v,loff_t * pos)1165 static void *synth_events_seq_next(struct seq_file *m, void *v, loff_t *pos)
1166 {
1167 return seq_list_next(v, &synth_event_list, pos);
1168 }
1169
synth_events_seq_stop(struct seq_file * m,void * v)1170 static void synth_events_seq_stop(struct seq_file *m, void *v)
1171 {
1172 mutex_unlock(&synth_event_mutex);
1173 }
1174
synth_events_seq_show(struct seq_file * m,void * v)1175 static int synth_events_seq_show(struct seq_file *m, void *v)
1176 {
1177 struct synth_field *field;
1178 struct synth_event *event = v;
1179 unsigned int i;
1180
1181 seq_printf(m, "%s\t", event->name);
1182
1183 for (i = 0; i < event->n_fields; i++) {
1184 field = event->fields[i];
1185
1186 /* parameter values */
1187 seq_printf(m, "%s %s%s", field->type, field->name,
1188 i == event->n_fields - 1 ? "" : "; ");
1189 }
1190
1191 seq_putc(m, '\n');
1192
1193 return 0;
1194 }
1195
1196 static const struct seq_operations synth_events_seq_op = {
1197 .start = synth_events_seq_start,
1198 .next = synth_events_seq_next,
1199 .stop = synth_events_seq_stop,
1200 .show = synth_events_seq_show
1201 };
1202
synth_events_open(struct inode * inode,struct file * file)1203 static int synth_events_open(struct inode *inode, struct file *file)
1204 {
1205 int ret;
1206
1207 if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
1208 ret = release_all_synth_events();
1209 if (ret < 0)
1210 return ret;
1211 }
1212
1213 return seq_open(file, &synth_events_seq_op);
1214 }
1215
synth_events_write(struct file * file,const char __user * buffer,size_t count,loff_t * ppos)1216 static ssize_t synth_events_write(struct file *file,
1217 const char __user *buffer,
1218 size_t count, loff_t *ppos)
1219 {
1220 return trace_parse_run_command(file, buffer, count, ppos,
1221 create_synth_event);
1222 }
1223
1224 static const struct file_operations synth_events_fops = {
1225 .open = synth_events_open,
1226 .write = synth_events_write,
1227 .read = seq_read,
1228 .llseek = seq_lseek,
1229 .release = seq_release,
1230 };
1231
hist_field_timestamp(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)1232 static u64 hist_field_timestamp(struct hist_field *hist_field,
1233 struct tracing_map_elt *elt,
1234 struct ring_buffer_event *rbe,
1235 void *event)
1236 {
1237 struct hist_trigger_data *hist_data = hist_field->hist_data;
1238 struct trace_array *tr = hist_data->event_file->tr;
1239
1240 u64 ts = ring_buffer_event_time_stamp(rbe);
1241
1242 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr))
1243 ts = ns2usecs(ts);
1244
1245 return ts;
1246 }
1247
hist_field_cpu(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)1248 static u64 hist_field_cpu(struct hist_field *hist_field,
1249 struct tracing_map_elt *elt,
1250 struct ring_buffer_event *rbe,
1251 void *event)
1252 {
1253 int cpu = smp_processor_id();
1254
1255 return cpu;
1256 }
1257
1258 static struct hist_field *
check_field_for_var_ref(struct hist_field * hist_field,struct hist_trigger_data * var_data,unsigned int var_idx)1259 check_field_for_var_ref(struct hist_field *hist_field,
1260 struct hist_trigger_data *var_data,
1261 unsigned int var_idx)
1262 {
1263 struct hist_field *found = NULL;
1264
1265 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF) {
1266 if (hist_field->var.idx == var_idx &&
1267 hist_field->var.hist_data == var_data) {
1268 found = hist_field;
1269 }
1270 }
1271
1272 return found;
1273 }
1274
1275 static struct hist_field *
check_field_for_var_refs(struct hist_trigger_data * hist_data,struct hist_field * hist_field,struct hist_trigger_data * var_data,unsigned int var_idx,unsigned int level)1276 check_field_for_var_refs(struct hist_trigger_data *hist_data,
1277 struct hist_field *hist_field,
1278 struct hist_trigger_data *var_data,
1279 unsigned int var_idx,
1280 unsigned int level)
1281 {
1282 struct hist_field *found = NULL;
1283 unsigned int i;
1284
1285 if (level > 3)
1286 return found;
1287
1288 if (!hist_field)
1289 return found;
1290
1291 found = check_field_for_var_ref(hist_field, var_data, var_idx);
1292 if (found)
1293 return found;
1294
1295 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
1296 struct hist_field *operand;
1297
1298 operand = hist_field->operands[i];
1299 found = check_field_for_var_refs(hist_data, operand, var_data,
1300 var_idx, level + 1);
1301 if (found)
1302 return found;
1303 }
1304
1305 return found;
1306 }
1307
find_var_ref(struct hist_trigger_data * hist_data,struct hist_trigger_data * var_data,unsigned int var_idx)1308 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data,
1309 struct hist_trigger_data *var_data,
1310 unsigned int var_idx)
1311 {
1312 struct hist_field *hist_field, *found = NULL;
1313 unsigned int i;
1314
1315 for_each_hist_field(i, hist_data) {
1316 hist_field = hist_data->fields[i];
1317 found = check_field_for_var_refs(hist_data, hist_field,
1318 var_data, var_idx, 0);
1319 if (found)
1320 return found;
1321 }
1322
1323 for (i = 0; i < hist_data->n_synth_var_refs; i++) {
1324 hist_field = hist_data->synth_var_refs[i];
1325 found = check_field_for_var_refs(hist_data, hist_field,
1326 var_data, var_idx, 0);
1327 if (found)
1328 return found;
1329 }
1330
1331 return found;
1332 }
1333
find_any_var_ref(struct hist_trigger_data * hist_data,unsigned int var_idx)1334 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data,
1335 unsigned int var_idx)
1336 {
1337 struct trace_array *tr = hist_data->event_file->tr;
1338 struct hist_field *found = NULL;
1339 struct hist_var_data *var_data;
1340
1341 list_for_each_entry(var_data, &tr->hist_vars, list) {
1342 if (var_data->hist_data == hist_data)
1343 continue;
1344 found = find_var_ref(var_data->hist_data, hist_data, var_idx);
1345 if (found)
1346 break;
1347 }
1348
1349 return found;
1350 }
1351
check_var_refs(struct hist_trigger_data * hist_data)1352 static bool check_var_refs(struct hist_trigger_data *hist_data)
1353 {
1354 struct hist_field *field;
1355 bool found = false;
1356 int i;
1357
1358 for_each_hist_field(i, hist_data) {
1359 field = hist_data->fields[i];
1360 if (field && field->flags & HIST_FIELD_FL_VAR) {
1361 if (find_any_var_ref(hist_data, field->var.idx)) {
1362 found = true;
1363 break;
1364 }
1365 }
1366 }
1367
1368 return found;
1369 }
1370
find_hist_vars(struct hist_trigger_data * hist_data)1371 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data)
1372 {
1373 struct trace_array *tr = hist_data->event_file->tr;
1374 struct hist_var_data *var_data, *found = NULL;
1375
1376 list_for_each_entry(var_data, &tr->hist_vars, list) {
1377 if (var_data->hist_data == hist_data) {
1378 found = var_data;
1379 break;
1380 }
1381 }
1382
1383 return found;
1384 }
1385
field_has_hist_vars(struct hist_field * hist_field,unsigned int level)1386 static bool field_has_hist_vars(struct hist_field *hist_field,
1387 unsigned int level)
1388 {
1389 int i;
1390
1391 if (level > 3)
1392 return false;
1393
1394 if (!hist_field)
1395 return false;
1396
1397 if (hist_field->flags & HIST_FIELD_FL_VAR ||
1398 hist_field->flags & HIST_FIELD_FL_VAR_REF)
1399 return true;
1400
1401 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
1402 struct hist_field *operand;
1403
1404 operand = hist_field->operands[i];
1405 if (field_has_hist_vars(operand, level + 1))
1406 return true;
1407 }
1408
1409 return false;
1410 }
1411
has_hist_vars(struct hist_trigger_data * hist_data)1412 static bool has_hist_vars(struct hist_trigger_data *hist_data)
1413 {
1414 struct hist_field *hist_field;
1415 int i;
1416
1417 for_each_hist_field(i, hist_data) {
1418 hist_field = hist_data->fields[i];
1419 if (field_has_hist_vars(hist_field, 0))
1420 return true;
1421 }
1422
1423 return false;
1424 }
1425
save_hist_vars(struct hist_trigger_data * hist_data)1426 static int save_hist_vars(struct hist_trigger_data *hist_data)
1427 {
1428 struct trace_array *tr = hist_data->event_file->tr;
1429 struct hist_var_data *var_data;
1430
1431 var_data = find_hist_vars(hist_data);
1432 if (var_data)
1433 return 0;
1434
1435 if (trace_array_get(tr) < 0)
1436 return -ENODEV;
1437
1438 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL);
1439 if (!var_data) {
1440 trace_array_put(tr);
1441 return -ENOMEM;
1442 }
1443
1444 var_data->hist_data = hist_data;
1445 list_add(&var_data->list, &tr->hist_vars);
1446
1447 return 0;
1448 }
1449
remove_hist_vars(struct hist_trigger_data * hist_data)1450 static void remove_hist_vars(struct hist_trigger_data *hist_data)
1451 {
1452 struct trace_array *tr = hist_data->event_file->tr;
1453 struct hist_var_data *var_data;
1454
1455 var_data = find_hist_vars(hist_data);
1456 if (!var_data)
1457 return;
1458
1459 if (WARN_ON(check_var_refs(hist_data)))
1460 return;
1461
1462 list_del(&var_data->list);
1463
1464 kfree(var_data);
1465
1466 trace_array_put(tr);
1467 }
1468
find_var_field(struct hist_trigger_data * hist_data,const char * var_name)1469 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data,
1470 const char *var_name)
1471 {
1472 struct hist_field *hist_field, *found = NULL;
1473 int i;
1474
1475 for_each_hist_field(i, hist_data) {
1476 hist_field = hist_data->fields[i];
1477 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR &&
1478 strcmp(hist_field->var.name, var_name) == 0) {
1479 found = hist_field;
1480 break;
1481 }
1482 }
1483
1484 return found;
1485 }
1486
find_var(struct hist_trigger_data * hist_data,struct trace_event_file * file,const char * var_name)1487 static struct hist_field *find_var(struct hist_trigger_data *hist_data,
1488 struct trace_event_file *file,
1489 const char *var_name)
1490 {
1491 struct hist_trigger_data *test_data;
1492 struct event_trigger_data *test;
1493 struct hist_field *hist_field;
1494
1495 hist_field = find_var_field(hist_data, var_name);
1496 if (hist_field)
1497 return hist_field;
1498
1499 list_for_each_entry_rcu(test, &file->triggers, list) {
1500 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
1501 test_data = test->private_data;
1502 hist_field = find_var_field(test_data, var_name);
1503 if (hist_field)
1504 return hist_field;
1505 }
1506 }
1507
1508 return NULL;
1509 }
1510
find_var_file(struct trace_array * tr,char * system,char * event_name,char * var_name)1511 static struct trace_event_file *find_var_file(struct trace_array *tr,
1512 char *system,
1513 char *event_name,
1514 char *var_name)
1515 {
1516 struct hist_trigger_data *var_hist_data;
1517 struct hist_var_data *var_data;
1518 struct trace_event_file *file, *found = NULL;
1519
1520 if (system)
1521 return find_event_file(tr, system, event_name);
1522
1523 list_for_each_entry(var_data, &tr->hist_vars, list) {
1524 var_hist_data = var_data->hist_data;
1525 file = var_hist_data->event_file;
1526 if (file == found)
1527 continue;
1528
1529 if (find_var_field(var_hist_data, var_name)) {
1530 if (found) {
1531 hist_err_event("Variable name not unique, need to use fully qualified name (subsys.event.var) for variable: ", system, event_name, var_name);
1532 return NULL;
1533 }
1534
1535 found = file;
1536 }
1537 }
1538
1539 return found;
1540 }
1541
find_file_var(struct trace_event_file * file,const char * var_name)1542 static struct hist_field *find_file_var(struct trace_event_file *file,
1543 const char *var_name)
1544 {
1545 struct hist_trigger_data *test_data;
1546 struct event_trigger_data *test;
1547 struct hist_field *hist_field;
1548
1549 list_for_each_entry_rcu(test, &file->triggers, list) {
1550 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
1551 test_data = test->private_data;
1552 hist_field = find_var_field(test_data, var_name);
1553 if (hist_field)
1554 return hist_field;
1555 }
1556 }
1557
1558 return NULL;
1559 }
1560
1561 static struct hist_field *
find_match_var(struct hist_trigger_data * hist_data,char * var_name)1562 find_match_var(struct hist_trigger_data *hist_data, char *var_name)
1563 {
1564 struct trace_array *tr = hist_data->event_file->tr;
1565 struct hist_field *hist_field, *found = NULL;
1566 struct trace_event_file *file;
1567 unsigned int i;
1568
1569 for (i = 0; i < hist_data->n_actions; i++) {
1570 struct action_data *data = hist_data->actions[i];
1571
1572 if (data->fn == action_trace) {
1573 char *system = data->onmatch.match_event_system;
1574 char *event_name = data->onmatch.match_event;
1575
1576 file = find_var_file(tr, system, event_name, var_name);
1577 if (!file)
1578 continue;
1579 hist_field = find_file_var(file, var_name);
1580 if (hist_field) {
1581 if (found) {
1582 hist_err_event("Variable name not unique, need to use fully qualified name (subsys.event.var) for variable: ", system, event_name, var_name);
1583 return ERR_PTR(-EINVAL);
1584 }
1585
1586 found = hist_field;
1587 }
1588 }
1589 }
1590 return found;
1591 }
1592
find_event_var(struct hist_trigger_data * hist_data,char * system,char * event_name,char * var_name)1593 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data,
1594 char *system,
1595 char *event_name,
1596 char *var_name)
1597 {
1598 struct trace_array *tr = hist_data->event_file->tr;
1599 struct hist_field *hist_field = NULL;
1600 struct trace_event_file *file;
1601
1602 if (!system || !event_name) {
1603 hist_field = find_match_var(hist_data, var_name);
1604 if (IS_ERR(hist_field))
1605 return NULL;
1606 if (hist_field)
1607 return hist_field;
1608 }
1609
1610 file = find_var_file(tr, system, event_name, var_name);
1611 if (!file)
1612 return NULL;
1613
1614 hist_field = find_file_var(file, var_name);
1615
1616 return hist_field;
1617 }
1618
1619 struct hist_elt_data {
1620 char *comm;
1621 u64 *var_ref_vals;
1622 char *field_var_str[SYNTH_FIELDS_MAX];
1623 };
1624
hist_field_var_ref(struct hist_field * hist_field,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * event)1625 static u64 hist_field_var_ref(struct hist_field *hist_field,
1626 struct tracing_map_elt *elt,
1627 struct ring_buffer_event *rbe,
1628 void *event)
1629 {
1630 struct hist_elt_data *elt_data;
1631 u64 var_val = 0;
1632
1633 elt_data = elt->private_data;
1634 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx];
1635
1636 return var_val;
1637 }
1638
resolve_var_refs(struct hist_trigger_data * hist_data,void * key,u64 * var_ref_vals,bool self)1639 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key,
1640 u64 *var_ref_vals, bool self)
1641 {
1642 struct hist_trigger_data *var_data;
1643 struct tracing_map_elt *var_elt;
1644 struct hist_field *hist_field;
1645 unsigned int i, var_idx;
1646 bool resolved = true;
1647 u64 var_val = 0;
1648
1649 for (i = 0; i < hist_data->n_var_refs; i++) {
1650 hist_field = hist_data->var_refs[i];
1651 var_idx = hist_field->var.idx;
1652 var_data = hist_field->var.hist_data;
1653
1654 if (var_data == NULL) {
1655 resolved = false;
1656 break;
1657 }
1658
1659 if ((self && var_data != hist_data) ||
1660 (!self && var_data == hist_data))
1661 continue;
1662
1663 var_elt = tracing_map_lookup(var_data->map, key);
1664 if (!var_elt) {
1665 resolved = false;
1666 break;
1667 }
1668
1669 if (!tracing_map_var_set(var_elt, var_idx)) {
1670 resolved = false;
1671 break;
1672 }
1673
1674 if (self || !hist_field->read_once)
1675 var_val = tracing_map_read_var(var_elt, var_idx);
1676 else
1677 var_val = tracing_map_read_var_once(var_elt, var_idx);
1678
1679 var_ref_vals[i] = var_val;
1680 }
1681
1682 return resolved;
1683 }
1684
hist_field_name(struct hist_field * field,unsigned int level)1685 static const char *hist_field_name(struct hist_field *field,
1686 unsigned int level)
1687 {
1688 const char *field_name = "";
1689
1690 if (level > 1)
1691 return field_name;
1692
1693 if (field->field)
1694 field_name = field->field->name;
1695 else if (field->flags & HIST_FIELD_FL_LOG2 ||
1696 field->flags & HIST_FIELD_FL_ALIAS)
1697 field_name = hist_field_name(field->operands[0], ++level);
1698 else if (field->flags & HIST_FIELD_FL_CPU)
1699 field_name = "cpu";
1700 else if (field->flags & HIST_FIELD_FL_EXPR ||
1701 field->flags & HIST_FIELD_FL_VAR_REF) {
1702 if (field->system) {
1703 static char full_name[MAX_FILTER_STR_VAL];
1704
1705 strcat(full_name, field->system);
1706 strcat(full_name, ".");
1707 strcat(full_name, field->event_name);
1708 strcat(full_name, ".");
1709 strcat(full_name, field->name);
1710 field_name = full_name;
1711 } else
1712 field_name = field->name;
1713 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP)
1714 field_name = "common_timestamp";
1715
1716 if (field_name == NULL)
1717 field_name = "";
1718
1719 return field_name;
1720 }
1721
select_value_fn(int field_size,int field_is_signed)1722 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed)
1723 {
1724 hist_field_fn_t fn = NULL;
1725
1726 switch (field_size) {
1727 case 8:
1728 if (field_is_signed)
1729 fn = hist_field_s64;
1730 else
1731 fn = hist_field_u64;
1732 break;
1733 case 4:
1734 if (field_is_signed)
1735 fn = hist_field_s32;
1736 else
1737 fn = hist_field_u32;
1738 break;
1739 case 2:
1740 if (field_is_signed)
1741 fn = hist_field_s16;
1742 else
1743 fn = hist_field_u16;
1744 break;
1745 case 1:
1746 if (field_is_signed)
1747 fn = hist_field_s8;
1748 else
1749 fn = hist_field_u8;
1750 break;
1751 }
1752
1753 return fn;
1754 }
1755
parse_map_size(char * str)1756 static int parse_map_size(char *str)
1757 {
1758 unsigned long size, map_bits;
1759 int ret;
1760
1761 strsep(&str, "=");
1762 if (!str) {
1763 ret = -EINVAL;
1764 goto out;
1765 }
1766
1767 ret = kstrtoul(str, 0, &size);
1768 if (ret)
1769 goto out;
1770
1771 map_bits = ilog2(roundup_pow_of_two(size));
1772 if (map_bits < TRACING_MAP_BITS_MIN ||
1773 map_bits > TRACING_MAP_BITS_MAX)
1774 ret = -EINVAL;
1775 else
1776 ret = map_bits;
1777 out:
1778 return ret;
1779 }
1780
destroy_hist_trigger_attrs(struct hist_trigger_attrs * attrs)1781 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
1782 {
1783 unsigned int i;
1784
1785 if (!attrs)
1786 return;
1787
1788 for (i = 0; i < attrs->n_assignments; i++)
1789 kfree(attrs->assignment_str[i]);
1790
1791 for (i = 0; i < attrs->n_actions; i++)
1792 kfree(attrs->action_str[i]);
1793
1794 kfree(attrs->name);
1795 kfree(attrs->sort_key_str);
1796 kfree(attrs->keys_str);
1797 kfree(attrs->vals_str);
1798 kfree(attrs->clock);
1799 kfree(attrs);
1800 }
1801
parse_action(char * str,struct hist_trigger_attrs * attrs)1802 static int parse_action(char *str, struct hist_trigger_attrs *attrs)
1803 {
1804 int ret = -EINVAL;
1805
1806 if (attrs->n_actions >= HIST_ACTIONS_MAX)
1807 return ret;
1808
1809 if ((strncmp(str, "onmatch(", strlen("onmatch(")) == 0) ||
1810 (strncmp(str, "onmax(", strlen("onmax(")) == 0)) {
1811 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL);
1812 if (!attrs->action_str[attrs->n_actions]) {
1813 ret = -ENOMEM;
1814 return ret;
1815 }
1816 attrs->n_actions++;
1817 ret = 0;
1818 }
1819
1820 return ret;
1821 }
1822
parse_assignment(char * str,struct hist_trigger_attrs * attrs)1823 static int parse_assignment(char *str, struct hist_trigger_attrs *attrs)
1824 {
1825 int ret = 0;
1826
1827 if ((strncmp(str, "key=", strlen("key=")) == 0) ||
1828 (strncmp(str, "keys=", strlen("keys=")) == 0)) {
1829 attrs->keys_str = kstrdup(str, GFP_KERNEL);
1830 if (!attrs->keys_str) {
1831 ret = -ENOMEM;
1832 goto out;
1833 }
1834 } else if ((strncmp(str, "val=", strlen("val=")) == 0) ||
1835 (strncmp(str, "vals=", strlen("vals=")) == 0) ||
1836 (strncmp(str, "values=", strlen("values=")) == 0)) {
1837 attrs->vals_str = kstrdup(str, GFP_KERNEL);
1838 if (!attrs->vals_str) {
1839 ret = -ENOMEM;
1840 goto out;
1841 }
1842 } else if (strncmp(str, "sort=", strlen("sort=")) == 0) {
1843 attrs->sort_key_str = kstrdup(str, GFP_KERNEL);
1844 if (!attrs->sort_key_str) {
1845 ret = -ENOMEM;
1846 goto out;
1847 }
1848 } else if (strncmp(str, "name=", strlen("name=")) == 0) {
1849 attrs->name = kstrdup(str, GFP_KERNEL);
1850 if (!attrs->name) {
1851 ret = -ENOMEM;
1852 goto out;
1853 }
1854 } else if (strncmp(str, "clock=", strlen("clock=")) == 0) {
1855 strsep(&str, "=");
1856 if (!str) {
1857 ret = -EINVAL;
1858 goto out;
1859 }
1860
1861 str = strstrip(str);
1862 attrs->clock = kstrdup(str, GFP_KERNEL);
1863 if (!attrs->clock) {
1864 ret = -ENOMEM;
1865 goto out;
1866 }
1867 } else if (strncmp(str, "size=", strlen("size=")) == 0) {
1868 int map_bits = parse_map_size(str);
1869
1870 if (map_bits < 0) {
1871 ret = map_bits;
1872 goto out;
1873 }
1874 attrs->map_bits = map_bits;
1875 } else {
1876 char *assignment;
1877
1878 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) {
1879 hist_err("Too many variables defined: ", str);
1880 ret = -EINVAL;
1881 goto out;
1882 }
1883
1884 assignment = kstrdup(str, GFP_KERNEL);
1885 if (!assignment) {
1886 ret = -ENOMEM;
1887 goto out;
1888 }
1889
1890 attrs->assignment_str[attrs->n_assignments++] = assignment;
1891 }
1892 out:
1893 return ret;
1894 }
1895
parse_hist_trigger_attrs(char * trigger_str)1896 static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
1897 {
1898 struct hist_trigger_attrs *attrs;
1899 int ret = 0;
1900
1901 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL);
1902 if (!attrs)
1903 return ERR_PTR(-ENOMEM);
1904
1905 while (trigger_str) {
1906 char *str = strsep(&trigger_str, ":");
1907
1908 if (strchr(str, '=')) {
1909 ret = parse_assignment(str, attrs);
1910 if (ret)
1911 goto free;
1912 } else if (strcmp(str, "pause") == 0)
1913 attrs->pause = true;
1914 else if ((strcmp(str, "cont") == 0) ||
1915 (strcmp(str, "continue") == 0))
1916 attrs->cont = true;
1917 else if (strcmp(str, "clear") == 0)
1918 attrs->clear = true;
1919 else {
1920 ret = parse_action(str, attrs);
1921 if (ret)
1922 goto free;
1923 }
1924 }
1925
1926 if (!attrs->keys_str) {
1927 ret = -EINVAL;
1928 goto free;
1929 }
1930
1931 if (!attrs->clock) {
1932 attrs->clock = kstrdup("global", GFP_KERNEL);
1933 if (!attrs->clock) {
1934 ret = -ENOMEM;
1935 goto free;
1936 }
1937 }
1938
1939 return attrs;
1940 free:
1941 destroy_hist_trigger_attrs(attrs);
1942
1943 return ERR_PTR(ret);
1944 }
1945
save_comm(char * comm,struct task_struct * task)1946 static inline void save_comm(char *comm, struct task_struct *task)
1947 {
1948 if (!task->pid) {
1949 strcpy(comm, "<idle>");
1950 return;
1951 }
1952
1953 if (WARN_ON_ONCE(task->pid < 0)) {
1954 strcpy(comm, "<XXX>");
1955 return;
1956 }
1957
1958 memcpy(comm, task->comm, TASK_COMM_LEN);
1959 }
1960
hist_elt_data_free(struct hist_elt_data * elt_data)1961 static void hist_elt_data_free(struct hist_elt_data *elt_data)
1962 {
1963 unsigned int i;
1964
1965 for (i = 0; i < SYNTH_FIELDS_MAX; i++)
1966 kfree(elt_data->field_var_str[i]);
1967
1968 kfree(elt_data->comm);
1969 kfree(elt_data);
1970 }
1971
hist_trigger_elt_data_free(struct tracing_map_elt * elt)1972 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt)
1973 {
1974 struct hist_elt_data *elt_data = elt->private_data;
1975
1976 hist_elt_data_free(elt_data);
1977 }
1978
hist_trigger_elt_data_alloc(struct tracing_map_elt * elt)1979 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
1980 {
1981 struct hist_trigger_data *hist_data = elt->map->private_data;
1982 unsigned int size = TASK_COMM_LEN;
1983 struct hist_elt_data *elt_data;
1984 struct hist_field *key_field;
1985 unsigned int i, n_str;
1986
1987 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
1988 if (!elt_data)
1989 return -ENOMEM;
1990
1991 for_each_hist_key_field(i, hist_data) {
1992 key_field = hist_data->fields[i];
1993
1994 if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
1995 elt_data->comm = kzalloc(size, GFP_KERNEL);
1996 if (!elt_data->comm) {
1997 kfree(elt_data);
1998 return -ENOMEM;
1999 }
2000 break;
2001 }
2002 }
2003
2004 n_str = hist_data->n_field_var_str + hist_data->n_max_var_str;
2005
2006 size = STR_VAR_LEN_MAX;
2007
2008 for (i = 0; i < n_str; i++) {
2009 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL);
2010 if (!elt_data->field_var_str[i]) {
2011 hist_elt_data_free(elt_data);
2012 return -ENOMEM;
2013 }
2014 }
2015
2016 elt->private_data = elt_data;
2017
2018 return 0;
2019 }
2020
hist_trigger_elt_data_init(struct tracing_map_elt * elt)2021 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt)
2022 {
2023 struct hist_elt_data *elt_data = elt->private_data;
2024
2025 if (elt_data->comm)
2026 save_comm(elt_data->comm, current);
2027 }
2028
2029 static const struct tracing_map_ops hist_trigger_elt_data_ops = {
2030 .elt_alloc = hist_trigger_elt_data_alloc,
2031 .elt_free = hist_trigger_elt_data_free,
2032 .elt_init = hist_trigger_elt_data_init,
2033 };
2034
get_hist_field_flags(struct hist_field * hist_field)2035 static const char *get_hist_field_flags(struct hist_field *hist_field)
2036 {
2037 const char *flags_str = NULL;
2038
2039 if (hist_field->flags & HIST_FIELD_FL_HEX)
2040 flags_str = "hex";
2041 else if (hist_field->flags & HIST_FIELD_FL_SYM)
2042 flags_str = "sym";
2043 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET)
2044 flags_str = "sym-offset";
2045 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME)
2046 flags_str = "execname";
2047 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL)
2048 flags_str = "syscall";
2049 else if (hist_field->flags & HIST_FIELD_FL_LOG2)
2050 flags_str = "log2";
2051 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS)
2052 flags_str = "usecs";
2053
2054 return flags_str;
2055 }
2056
expr_field_str(struct hist_field * field,char * expr)2057 static void expr_field_str(struct hist_field *field, char *expr)
2058 {
2059 if (field->flags & HIST_FIELD_FL_VAR_REF)
2060 strcat(expr, "$");
2061
2062 strcat(expr, hist_field_name(field, 0));
2063
2064 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) {
2065 const char *flags_str = get_hist_field_flags(field);
2066
2067 if (flags_str) {
2068 strcat(expr, ".");
2069 strcat(expr, flags_str);
2070 }
2071 }
2072 }
2073
expr_str(struct hist_field * field,unsigned int level)2074 static char *expr_str(struct hist_field *field, unsigned int level)
2075 {
2076 char *expr;
2077
2078 if (level > 1)
2079 return NULL;
2080
2081 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2082 if (!expr)
2083 return NULL;
2084
2085 if (!field->operands[0]) {
2086 expr_field_str(field, expr);
2087 return expr;
2088 }
2089
2090 if (field->operator == FIELD_OP_UNARY_MINUS) {
2091 char *subexpr;
2092
2093 strcat(expr, "-(");
2094 subexpr = expr_str(field->operands[0], ++level);
2095 if (!subexpr) {
2096 kfree(expr);
2097 return NULL;
2098 }
2099 strcat(expr, subexpr);
2100 strcat(expr, ")");
2101
2102 kfree(subexpr);
2103
2104 return expr;
2105 }
2106
2107 expr_field_str(field->operands[0], expr);
2108
2109 switch (field->operator) {
2110 case FIELD_OP_MINUS:
2111 strcat(expr, "-");
2112 break;
2113 case FIELD_OP_PLUS:
2114 strcat(expr, "+");
2115 break;
2116 default:
2117 kfree(expr);
2118 return NULL;
2119 }
2120
2121 expr_field_str(field->operands[1], expr);
2122
2123 return expr;
2124 }
2125
contains_operator(char * str)2126 static int contains_operator(char *str)
2127 {
2128 enum field_op_id field_op = FIELD_OP_NONE;
2129 char *op;
2130
2131 op = strpbrk(str, "+-");
2132 if (!op)
2133 return FIELD_OP_NONE;
2134
2135 switch (*op) {
2136 case '-':
2137 if (*str == '-')
2138 field_op = FIELD_OP_UNARY_MINUS;
2139 else
2140 field_op = FIELD_OP_MINUS;
2141 break;
2142 case '+':
2143 field_op = FIELD_OP_PLUS;
2144 break;
2145 default:
2146 break;
2147 }
2148
2149 return field_op;
2150 }
2151
destroy_hist_field(struct hist_field * hist_field,unsigned int level)2152 static void destroy_hist_field(struct hist_field *hist_field,
2153 unsigned int level)
2154 {
2155 unsigned int i;
2156
2157 if (level > 3)
2158 return;
2159
2160 if (!hist_field)
2161 return;
2162
2163 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++)
2164 destroy_hist_field(hist_field->operands[i], level + 1);
2165
2166 kfree(hist_field->var.name);
2167 kfree(hist_field->name);
2168 kfree(hist_field->type);
2169
2170 kfree(hist_field);
2171 }
2172
create_hist_field(struct hist_trigger_data * hist_data,struct ftrace_event_field * field,unsigned long flags,char * var_name)2173 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
2174 struct ftrace_event_field *field,
2175 unsigned long flags,
2176 char *var_name)
2177 {
2178 struct hist_field *hist_field;
2179
2180 if (field && is_function_field(field))
2181 return NULL;
2182
2183 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
2184 if (!hist_field)
2185 return NULL;
2186
2187 hist_field->hist_data = hist_data;
2188
2189 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS)
2190 goto out; /* caller will populate */
2191
2192 if (flags & HIST_FIELD_FL_VAR_REF) {
2193 hist_field->fn = hist_field_var_ref;
2194 goto out;
2195 }
2196
2197 if (flags & HIST_FIELD_FL_HITCOUNT) {
2198 hist_field->fn = hist_field_counter;
2199 hist_field->size = sizeof(u64);
2200 hist_field->type = kstrdup("u64", GFP_KERNEL);
2201 if (!hist_field->type)
2202 goto free;
2203 goto out;
2204 }
2205
2206 if (flags & HIST_FIELD_FL_STACKTRACE) {
2207 hist_field->fn = hist_field_none;
2208 goto out;
2209 }
2210
2211 if (flags & HIST_FIELD_FL_LOG2) {
2212 unsigned long fl = flags & ~HIST_FIELD_FL_LOG2;
2213 hist_field->fn = hist_field_log2;
2214 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL);
2215 hist_field->size = hist_field->operands[0]->size;
2216 hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL);
2217 if (!hist_field->type)
2218 goto free;
2219 goto out;
2220 }
2221
2222 if (flags & HIST_FIELD_FL_TIMESTAMP) {
2223 hist_field->fn = hist_field_timestamp;
2224 hist_field->size = sizeof(u64);
2225 hist_field->type = kstrdup("u64", GFP_KERNEL);
2226 if (!hist_field->type)
2227 goto free;
2228 goto out;
2229 }
2230
2231 if (flags & HIST_FIELD_FL_CPU) {
2232 hist_field->fn = hist_field_cpu;
2233 hist_field->size = sizeof(int);
2234 hist_field->type = kstrdup("unsigned int", GFP_KERNEL);
2235 if (!hist_field->type)
2236 goto free;
2237 goto out;
2238 }
2239
2240 if (WARN_ON_ONCE(!field))
2241 goto out;
2242
2243 if (is_string_field(field)) {
2244 flags |= HIST_FIELD_FL_STRING;
2245
2246 hist_field->size = MAX_FILTER_STR_VAL;
2247 hist_field->type = kstrdup(field->type, GFP_KERNEL);
2248 if (!hist_field->type)
2249 goto free;
2250
2251 if (field->filter_type == FILTER_STATIC_STRING)
2252 hist_field->fn = hist_field_string;
2253 else if (field->filter_type == FILTER_DYN_STRING)
2254 hist_field->fn = hist_field_dynstring;
2255 else
2256 hist_field->fn = hist_field_pstring;
2257 } else {
2258 hist_field->size = field->size;
2259 hist_field->is_signed = field->is_signed;
2260 hist_field->type = kstrdup(field->type, GFP_KERNEL);
2261 if (!hist_field->type)
2262 goto free;
2263
2264 hist_field->fn = select_value_fn(field->size,
2265 field->is_signed);
2266 if (!hist_field->fn) {
2267 destroy_hist_field(hist_field, 0);
2268 return NULL;
2269 }
2270 }
2271 out:
2272 hist_field->field = field;
2273 hist_field->flags = flags;
2274
2275 if (var_name) {
2276 hist_field->var.name = kstrdup(var_name, GFP_KERNEL);
2277 if (!hist_field->var.name)
2278 goto free;
2279 }
2280
2281 return hist_field;
2282 free:
2283 destroy_hist_field(hist_field, 0);
2284 return NULL;
2285 }
2286
destroy_hist_fields(struct hist_trigger_data * hist_data)2287 static void destroy_hist_fields(struct hist_trigger_data *hist_data)
2288 {
2289 unsigned int i;
2290
2291 for (i = 0; i < HIST_FIELDS_MAX; i++) {
2292 if (hist_data->fields[i]) {
2293 destroy_hist_field(hist_data->fields[i], 0);
2294 hist_data->fields[i] = NULL;
2295 }
2296 }
2297 }
2298
init_var_ref(struct hist_field * ref_field,struct hist_field * var_field,char * system,char * event_name)2299 static int init_var_ref(struct hist_field *ref_field,
2300 struct hist_field *var_field,
2301 char *system, char *event_name)
2302 {
2303 int err = 0;
2304
2305 ref_field->var.idx = var_field->var.idx;
2306 ref_field->var.hist_data = var_field->hist_data;
2307 ref_field->size = var_field->size;
2308 ref_field->is_signed = var_field->is_signed;
2309 ref_field->flags |= var_field->flags &
2310 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2311
2312 if (system) {
2313 ref_field->system = kstrdup(system, GFP_KERNEL);
2314 if (!ref_field->system)
2315 return -ENOMEM;
2316 }
2317
2318 if (event_name) {
2319 ref_field->event_name = kstrdup(event_name, GFP_KERNEL);
2320 if (!ref_field->event_name) {
2321 err = -ENOMEM;
2322 goto free;
2323 }
2324 }
2325
2326 if (var_field->var.name) {
2327 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL);
2328 if (!ref_field->name) {
2329 err = -ENOMEM;
2330 goto free;
2331 }
2332 } else if (var_field->name) {
2333 ref_field->name = kstrdup(var_field->name, GFP_KERNEL);
2334 if (!ref_field->name) {
2335 err = -ENOMEM;
2336 goto free;
2337 }
2338 }
2339
2340 ref_field->type = kstrdup(var_field->type, GFP_KERNEL);
2341 if (!ref_field->type) {
2342 err = -ENOMEM;
2343 goto free;
2344 }
2345 out:
2346 return err;
2347 free:
2348 kfree(ref_field->system);
2349 kfree(ref_field->event_name);
2350 kfree(ref_field->name);
2351
2352 goto out;
2353 }
2354
create_var_ref(struct hist_field * var_field,char * system,char * event_name)2355 static struct hist_field *create_var_ref(struct hist_field *var_field,
2356 char *system, char *event_name)
2357 {
2358 unsigned long flags = HIST_FIELD_FL_VAR_REF;
2359 struct hist_field *ref_field;
2360
2361 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL);
2362 if (ref_field) {
2363 if (init_var_ref(ref_field, var_field, system, event_name)) {
2364 destroy_hist_field(ref_field, 0);
2365 return NULL;
2366 }
2367 }
2368
2369 return ref_field;
2370 }
2371
is_var_ref(char * var_name)2372 static bool is_var_ref(char *var_name)
2373 {
2374 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$')
2375 return false;
2376
2377 return true;
2378 }
2379
field_name_from_var(struct hist_trigger_data * hist_data,char * var_name)2380 static char *field_name_from_var(struct hist_trigger_data *hist_data,
2381 char *var_name)
2382 {
2383 char *name, *field;
2384 unsigned int i;
2385
2386 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
2387 name = hist_data->attrs->var_defs.name[i];
2388
2389 if (strcmp(var_name, name) == 0) {
2390 field = hist_data->attrs->var_defs.expr[i];
2391 if (contains_operator(field) || is_var_ref(field))
2392 continue;
2393 return field;
2394 }
2395 }
2396
2397 return NULL;
2398 }
2399
local_field_var_ref(struct hist_trigger_data * hist_data,char * system,char * event_name,char * var_name)2400 static char *local_field_var_ref(struct hist_trigger_data *hist_data,
2401 char *system, char *event_name,
2402 char *var_name)
2403 {
2404 struct trace_event_call *call;
2405
2406 if (system && event_name) {
2407 call = hist_data->event_file->event_call;
2408
2409 if (strcmp(system, call->class->system) != 0)
2410 return NULL;
2411
2412 if (strcmp(event_name, trace_event_name(call)) != 0)
2413 return NULL;
2414 }
2415
2416 if (!!system != !!event_name)
2417 return NULL;
2418
2419 if (!is_var_ref(var_name))
2420 return NULL;
2421
2422 var_name++;
2423
2424 return field_name_from_var(hist_data, var_name);
2425 }
2426
parse_var_ref(struct hist_trigger_data * hist_data,char * system,char * event_name,char * var_name)2427 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data,
2428 char *system, char *event_name,
2429 char *var_name)
2430 {
2431 struct hist_field *var_field = NULL, *ref_field = NULL;
2432
2433 if (!is_var_ref(var_name))
2434 return NULL;
2435
2436 var_name++;
2437
2438 var_field = find_event_var(hist_data, system, event_name, var_name);
2439 if (var_field)
2440 ref_field = create_var_ref(var_field, system, event_name);
2441
2442 if (!ref_field)
2443 hist_err_event("Couldn't find variable: $",
2444 system, event_name, var_name);
2445
2446 return ref_field;
2447 }
2448
2449 static struct ftrace_event_field *
parse_field(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * field_str,unsigned long * flags)2450 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
2451 char *field_str, unsigned long *flags)
2452 {
2453 struct ftrace_event_field *field = NULL;
2454 char *field_name, *modifier, *str;
2455
2456 modifier = str = kstrdup(field_str, GFP_KERNEL);
2457 if (!modifier)
2458 return ERR_PTR(-ENOMEM);
2459
2460 field_name = strsep(&modifier, ".");
2461 if (modifier) {
2462 if (strcmp(modifier, "hex") == 0)
2463 *flags |= HIST_FIELD_FL_HEX;
2464 else if (strcmp(modifier, "sym") == 0)
2465 *flags |= HIST_FIELD_FL_SYM;
2466 else if (strcmp(modifier, "sym-offset") == 0)
2467 *flags |= HIST_FIELD_FL_SYM_OFFSET;
2468 else if ((strcmp(modifier, "execname") == 0) &&
2469 (strcmp(field_name, "common_pid") == 0))
2470 *flags |= HIST_FIELD_FL_EXECNAME;
2471 else if (strcmp(modifier, "syscall") == 0)
2472 *flags |= HIST_FIELD_FL_SYSCALL;
2473 else if (strcmp(modifier, "log2") == 0)
2474 *flags |= HIST_FIELD_FL_LOG2;
2475 else if (strcmp(modifier, "usecs") == 0)
2476 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS;
2477 else {
2478 hist_err("Invalid field modifier: ", modifier);
2479 field = ERR_PTR(-EINVAL);
2480 goto out;
2481 }
2482 }
2483
2484 if (strcmp(field_name, "common_timestamp") == 0) {
2485 *flags |= HIST_FIELD_FL_TIMESTAMP;
2486 hist_data->enable_timestamps = true;
2487 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS)
2488 hist_data->attrs->ts_in_usecs = true;
2489 } else if (strcmp(field_name, "cpu") == 0)
2490 *flags |= HIST_FIELD_FL_CPU;
2491 else {
2492 field = trace_find_event_field(file->event_call, field_name);
2493 if (!field || !field->size) {
2494 hist_err("Couldn't find field: ", field_name);
2495 field = ERR_PTR(-EINVAL);
2496 goto out;
2497 }
2498 }
2499 out:
2500 kfree(str);
2501
2502 return field;
2503 }
2504
create_alias(struct hist_trigger_data * hist_data,struct hist_field * var_ref,char * var_name)2505 static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
2506 struct hist_field *var_ref,
2507 char *var_name)
2508 {
2509 struct hist_field *alias = NULL;
2510 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR;
2511
2512 alias = create_hist_field(hist_data, NULL, flags, var_name);
2513 if (!alias)
2514 return NULL;
2515
2516 alias->fn = var_ref->fn;
2517 alias->operands[0] = var_ref;
2518
2519 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) {
2520 destroy_hist_field(alias, 0);
2521 return NULL;
2522 }
2523
2524 return alias;
2525 }
2526
parse_atom(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long * flags,char * var_name)2527 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
2528 struct trace_event_file *file, char *str,
2529 unsigned long *flags, char *var_name)
2530 {
2531 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
2532 struct ftrace_event_field *field = NULL;
2533 struct hist_field *hist_field = NULL;
2534 int ret = 0;
2535
2536 s = strchr(str, '.');
2537 if (s) {
2538 s = strchr(++s, '.');
2539 if (s) {
2540 ref_system = strsep(&str, ".");
2541 if (!str) {
2542 ret = -EINVAL;
2543 goto out;
2544 }
2545 ref_event = strsep(&str, ".");
2546 if (!str) {
2547 ret = -EINVAL;
2548 goto out;
2549 }
2550 ref_var = str;
2551 }
2552 }
2553
2554 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var);
2555 if (!s) {
2556 hist_field = parse_var_ref(hist_data, ref_system, ref_event, ref_var);
2557 if (hist_field) {
2558 hist_data->var_refs[hist_data->n_var_refs] = hist_field;
2559 hist_field->var_ref_idx = hist_data->n_var_refs++;
2560 if (var_name) {
2561 hist_field = create_alias(hist_data, hist_field, var_name);
2562 if (!hist_field) {
2563 ret = -ENOMEM;
2564 goto out;
2565 }
2566 }
2567 return hist_field;
2568 }
2569 } else
2570 str = s;
2571
2572 field = parse_field(hist_data, file, str, flags);
2573 if (IS_ERR(field)) {
2574 ret = PTR_ERR(field);
2575 goto out;
2576 }
2577
2578 hist_field = create_hist_field(hist_data, field, *flags, var_name);
2579 if (!hist_field) {
2580 ret = -ENOMEM;
2581 goto out;
2582 }
2583
2584 return hist_field;
2585 out:
2586 return ERR_PTR(ret);
2587 }
2588
2589 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2590 struct trace_event_file *file,
2591 char *str, unsigned long flags,
2592 char *var_name, unsigned int level);
2593
parse_unary(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long flags,char * var_name,unsigned int level)2594 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
2595 struct trace_event_file *file,
2596 char *str, unsigned long flags,
2597 char *var_name, unsigned int level)
2598 {
2599 struct hist_field *operand1, *expr = NULL;
2600 unsigned long operand_flags;
2601 int ret = 0;
2602 char *s;
2603
2604 /* we support only -(xxx) i.e. explicit parens required */
2605
2606 if (level > 3) {
2607 hist_err("Too many subexpressions (3 max): ", str);
2608 ret = -EINVAL;
2609 goto free;
2610 }
2611
2612 str++; /* skip leading '-' */
2613
2614 s = strchr(str, '(');
2615 if (s)
2616 str++;
2617 else {
2618 ret = -EINVAL;
2619 goto free;
2620 }
2621
2622 s = strrchr(str, ')');
2623 if (s)
2624 *s = '\0';
2625 else {
2626 ret = -EINVAL; /* no closing ')' */
2627 goto free;
2628 }
2629
2630 flags |= HIST_FIELD_FL_EXPR;
2631 expr = create_hist_field(hist_data, NULL, flags, var_name);
2632 if (!expr) {
2633 ret = -ENOMEM;
2634 goto free;
2635 }
2636
2637 operand_flags = 0;
2638 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2639 if (IS_ERR(operand1)) {
2640 ret = PTR_ERR(operand1);
2641 goto free;
2642 }
2643
2644 expr->flags |= operand1->flags &
2645 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2646 expr->fn = hist_field_unary_minus;
2647 expr->operands[0] = operand1;
2648 expr->operator = FIELD_OP_UNARY_MINUS;
2649 expr->name = expr_str(expr, 0);
2650 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2651 if (!expr->type) {
2652 ret = -ENOMEM;
2653 goto free;
2654 }
2655
2656 return expr;
2657 free:
2658 destroy_hist_field(expr, 0);
2659 return ERR_PTR(ret);
2660 }
2661
check_expr_operands(struct hist_field * operand1,struct hist_field * operand2)2662 static int check_expr_operands(struct hist_field *operand1,
2663 struct hist_field *operand2)
2664 {
2665 unsigned long operand1_flags = operand1->flags;
2666 unsigned long operand2_flags = operand2->flags;
2667
2668 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) ||
2669 (operand1_flags & HIST_FIELD_FL_ALIAS)) {
2670 struct hist_field *var;
2671
2672 var = find_var_field(operand1->var.hist_data, operand1->name);
2673 if (!var)
2674 return -EINVAL;
2675 operand1_flags = var->flags;
2676 }
2677
2678 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) ||
2679 (operand2_flags & HIST_FIELD_FL_ALIAS)) {
2680 struct hist_field *var;
2681
2682 var = find_var_field(operand2->var.hist_data, operand2->name);
2683 if (!var)
2684 return -EINVAL;
2685 operand2_flags = var->flags;
2686 }
2687
2688 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) !=
2689 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) {
2690 hist_err("Timestamp units in expression don't match", NULL);
2691 return -EINVAL;
2692 }
2693
2694 return 0;
2695 }
2696
parse_expr(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * str,unsigned long flags,char * var_name,unsigned int level)2697 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2698 struct trace_event_file *file,
2699 char *str, unsigned long flags,
2700 char *var_name, unsigned int level)
2701 {
2702 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL;
2703 unsigned long operand_flags;
2704 int field_op, ret = -EINVAL;
2705 char *sep, *operand1_str;
2706
2707 if (level > 3) {
2708 hist_err("Too many subexpressions (3 max): ", str);
2709 return ERR_PTR(-EINVAL);
2710 }
2711
2712 field_op = contains_operator(str);
2713
2714 if (field_op == FIELD_OP_NONE)
2715 return parse_atom(hist_data, file, str, &flags, var_name);
2716
2717 if (field_op == FIELD_OP_UNARY_MINUS)
2718 return parse_unary(hist_data, file, str, flags, var_name, ++level);
2719
2720 switch (field_op) {
2721 case FIELD_OP_MINUS:
2722 sep = "-";
2723 break;
2724 case FIELD_OP_PLUS:
2725 sep = "+";
2726 break;
2727 default:
2728 goto free;
2729 }
2730
2731 operand1_str = strsep(&str, sep);
2732 if (!operand1_str || !str)
2733 goto free;
2734
2735 operand_flags = 0;
2736 operand1 = parse_atom(hist_data, file, operand1_str,
2737 &operand_flags, NULL);
2738 if (IS_ERR(operand1)) {
2739 ret = PTR_ERR(operand1);
2740 operand1 = NULL;
2741 goto free;
2742 }
2743
2744 /* rest of string could be another expression e.g. b+c in a+b+c */
2745 operand_flags = 0;
2746 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2747 if (IS_ERR(operand2)) {
2748 ret = PTR_ERR(operand2);
2749 operand2 = NULL;
2750 goto free;
2751 }
2752
2753 ret = check_expr_operands(operand1, operand2);
2754 if (ret)
2755 goto free;
2756
2757 flags |= HIST_FIELD_FL_EXPR;
2758
2759 flags |= operand1->flags &
2760 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2761
2762 expr = create_hist_field(hist_data, NULL, flags, var_name);
2763 if (!expr) {
2764 ret = -ENOMEM;
2765 goto free;
2766 }
2767
2768 operand1->read_once = true;
2769 operand2->read_once = true;
2770
2771 expr->operands[0] = operand1;
2772 expr->operands[1] = operand2;
2773 expr->operator = field_op;
2774 expr->name = expr_str(expr, 0);
2775 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2776 if (!expr->type) {
2777 ret = -ENOMEM;
2778 goto free;
2779 }
2780
2781 switch (field_op) {
2782 case FIELD_OP_MINUS:
2783 expr->fn = hist_field_minus;
2784 break;
2785 case FIELD_OP_PLUS:
2786 expr->fn = hist_field_plus;
2787 break;
2788 default:
2789 ret = -EINVAL;
2790 goto free;
2791 }
2792
2793 return expr;
2794 free:
2795 destroy_hist_field(operand1, 0);
2796 destroy_hist_field(operand2, 0);
2797 destroy_hist_field(expr, 0);
2798
2799 return ERR_PTR(ret);
2800 }
2801
find_trigger_filter(struct hist_trigger_data * hist_data,struct trace_event_file * file)2802 static char *find_trigger_filter(struct hist_trigger_data *hist_data,
2803 struct trace_event_file *file)
2804 {
2805 struct event_trigger_data *test;
2806
2807 list_for_each_entry_rcu(test, &file->triggers, list) {
2808 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2809 if (test->private_data == hist_data)
2810 return test->filter_str;
2811 }
2812 }
2813
2814 return NULL;
2815 }
2816
2817 static struct event_command trigger_hist_cmd;
2818 static int event_hist_trigger_func(struct event_command *cmd_ops,
2819 struct trace_event_file *file,
2820 char *glob, char *cmd, char *param);
2821
compatible_keys(struct hist_trigger_data * target_hist_data,struct hist_trigger_data * hist_data,unsigned int n_keys)2822 static bool compatible_keys(struct hist_trigger_data *target_hist_data,
2823 struct hist_trigger_data *hist_data,
2824 unsigned int n_keys)
2825 {
2826 struct hist_field *target_hist_field, *hist_field;
2827 unsigned int n, i, j;
2828
2829 if (hist_data->n_fields - hist_data->n_vals != n_keys)
2830 return false;
2831
2832 i = hist_data->n_vals;
2833 j = target_hist_data->n_vals;
2834
2835 for (n = 0; n < n_keys; n++) {
2836 hist_field = hist_data->fields[i + n];
2837 target_hist_field = target_hist_data->fields[j + n];
2838
2839 if (strcmp(hist_field->type, target_hist_field->type) != 0)
2840 return false;
2841 if (hist_field->size != target_hist_field->size)
2842 return false;
2843 if (hist_field->is_signed != target_hist_field->is_signed)
2844 return false;
2845 }
2846
2847 return true;
2848 }
2849
2850 static struct hist_trigger_data *
find_compatible_hist(struct hist_trigger_data * target_hist_data,struct trace_event_file * file)2851 find_compatible_hist(struct hist_trigger_data *target_hist_data,
2852 struct trace_event_file *file)
2853 {
2854 struct hist_trigger_data *hist_data;
2855 struct event_trigger_data *test;
2856 unsigned int n_keys;
2857
2858 n_keys = target_hist_data->n_fields - target_hist_data->n_vals;
2859
2860 list_for_each_entry_rcu(test, &file->triggers, list) {
2861 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2862 hist_data = test->private_data;
2863
2864 if (compatible_keys(target_hist_data, hist_data, n_keys))
2865 return hist_data;
2866 }
2867 }
2868
2869 return NULL;
2870 }
2871
event_file(struct trace_array * tr,char * system,char * event_name)2872 static struct trace_event_file *event_file(struct trace_array *tr,
2873 char *system, char *event_name)
2874 {
2875 struct trace_event_file *file;
2876
2877 file = __find_event_file(tr, system, event_name);
2878 if (!file)
2879 return ERR_PTR(-EINVAL);
2880
2881 return file;
2882 }
2883
2884 static struct hist_field *
find_synthetic_field_var(struct hist_trigger_data * target_hist_data,char * system,char * event_name,char * field_name)2885 find_synthetic_field_var(struct hist_trigger_data *target_hist_data,
2886 char *system, char *event_name, char *field_name)
2887 {
2888 struct hist_field *event_var;
2889 char *synthetic_name;
2890
2891 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2892 if (!synthetic_name)
2893 return ERR_PTR(-ENOMEM);
2894
2895 strcpy(synthetic_name, "synthetic_");
2896 strcat(synthetic_name, field_name);
2897
2898 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name);
2899
2900 kfree(synthetic_name);
2901
2902 return event_var;
2903 }
2904
2905 /**
2906 * create_field_var_hist - Automatically create a histogram and var for a field
2907 * @target_hist_data: The target hist trigger
2908 * @subsys_name: Optional subsystem name
2909 * @event_name: Optional event name
2910 * @field_name: The name of the field (and the resulting variable)
2911 *
2912 * Hist trigger actions fetch data from variables, not directly from
2913 * events. However, for convenience, users are allowed to directly
2914 * specify an event field in an action, which will be automatically
2915 * converted into a variable on their behalf.
2916
2917 * If a user specifies a field on an event that isn't the event the
2918 * histogram currently being defined (the target event histogram), the
2919 * only way that can be accomplished is if a new hist trigger is
2920 * created and the field variable defined on that.
2921 *
2922 * This function creates a new histogram compatible with the target
2923 * event (meaning a histogram with the same key as the target
2924 * histogram), and creates a variable for the specified field, but
2925 * with 'synthetic_' prepended to the variable name in order to avoid
2926 * collision with normal field variables.
2927 *
2928 * Return: The variable created for the field.
2929 */
2930 static struct hist_field *
create_field_var_hist(struct hist_trigger_data * target_hist_data,char * subsys_name,char * event_name,char * field_name)2931 create_field_var_hist(struct hist_trigger_data *target_hist_data,
2932 char *subsys_name, char *event_name, char *field_name)
2933 {
2934 struct trace_array *tr = target_hist_data->event_file->tr;
2935 struct hist_field *event_var = ERR_PTR(-EINVAL);
2936 struct hist_trigger_data *hist_data;
2937 unsigned int i, n, first = true;
2938 struct field_var_hist *var_hist;
2939 struct trace_event_file *file;
2940 struct hist_field *key_field;
2941 char *saved_filter;
2942 char *cmd;
2943 int ret;
2944
2945 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) {
2946 hist_err_event("onmatch: Too many field variables defined: ",
2947 subsys_name, event_name, field_name);
2948 return ERR_PTR(-EINVAL);
2949 }
2950
2951 file = event_file(tr, subsys_name, event_name);
2952
2953 if (IS_ERR(file)) {
2954 hist_err_event("onmatch: Event file not found: ",
2955 subsys_name, event_name, field_name);
2956 ret = PTR_ERR(file);
2957 return ERR_PTR(ret);
2958 }
2959
2960 /*
2961 * Look for a histogram compatible with target. We'll use the
2962 * found histogram specification to create a new matching
2963 * histogram with our variable on it. target_hist_data is not
2964 * yet a registered histogram so we can't use that.
2965 */
2966 hist_data = find_compatible_hist(target_hist_data, file);
2967 if (!hist_data) {
2968 hist_err_event("onmatch: Matching event histogram not found: ",
2969 subsys_name, event_name, field_name);
2970 return ERR_PTR(-EINVAL);
2971 }
2972
2973 /* See if a synthetic field variable has already been created */
2974 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
2975 event_name, field_name);
2976 if (!IS_ERR_OR_NULL(event_var))
2977 return event_var;
2978
2979 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL);
2980 if (!var_hist)
2981 return ERR_PTR(-ENOMEM);
2982
2983 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2984 if (!cmd) {
2985 kfree(var_hist);
2986 return ERR_PTR(-ENOMEM);
2987 }
2988
2989 /* Use the same keys as the compatible histogram */
2990 strcat(cmd, "keys=");
2991
2992 for_each_hist_key_field(i, hist_data) {
2993 key_field = hist_data->fields[i];
2994 if (!first)
2995 strcat(cmd, ",");
2996 strcat(cmd, key_field->field->name);
2997 first = false;
2998 }
2999
3000 /* Create the synthetic field variable specification */
3001 strcat(cmd, ":synthetic_");
3002 strcat(cmd, field_name);
3003 strcat(cmd, "=");
3004 strcat(cmd, field_name);
3005
3006 /* Use the same filter as the compatible histogram */
3007 saved_filter = find_trigger_filter(hist_data, file);
3008 if (saved_filter) {
3009 strcat(cmd, " if ");
3010 strcat(cmd, saved_filter);
3011 }
3012
3013 var_hist->cmd = kstrdup(cmd, GFP_KERNEL);
3014 if (!var_hist->cmd) {
3015 kfree(cmd);
3016 kfree(var_hist);
3017 return ERR_PTR(-ENOMEM);
3018 }
3019
3020 /* Save the compatible histogram information */
3021 var_hist->hist_data = hist_data;
3022
3023 /* Create the new histogram with our variable */
3024 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
3025 "", "hist", cmd);
3026 if (ret) {
3027 kfree(cmd);
3028 kfree(var_hist->cmd);
3029 kfree(var_hist);
3030 hist_err_event("onmatch: Couldn't create histogram for field: ",
3031 subsys_name, event_name, field_name);
3032 return ERR_PTR(ret);
3033 }
3034
3035 kfree(cmd);
3036
3037 /* If we can't find the variable, something went wrong */
3038 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
3039 event_name, field_name);
3040 if (IS_ERR_OR_NULL(event_var)) {
3041 kfree(var_hist->cmd);
3042 kfree(var_hist);
3043 hist_err_event("onmatch: Couldn't find synthetic variable: ",
3044 subsys_name, event_name, field_name);
3045 return ERR_PTR(-EINVAL);
3046 }
3047
3048 n = target_hist_data->n_field_var_hists;
3049 target_hist_data->field_var_hists[n] = var_hist;
3050 target_hist_data->n_field_var_hists++;
3051
3052 return event_var;
3053 }
3054
3055 static struct hist_field *
find_target_event_var(struct hist_trigger_data * hist_data,char * subsys_name,char * event_name,char * var_name)3056 find_target_event_var(struct hist_trigger_data *hist_data,
3057 char *subsys_name, char *event_name, char *var_name)
3058 {
3059 struct trace_event_file *file = hist_data->event_file;
3060 struct hist_field *hist_field = NULL;
3061
3062 if (subsys_name) {
3063 struct trace_event_call *call;
3064
3065 if (!event_name)
3066 return NULL;
3067
3068 call = file->event_call;
3069
3070 if (strcmp(subsys_name, call->class->system) != 0)
3071 return NULL;
3072
3073 if (strcmp(event_name, trace_event_name(call)) != 0)
3074 return NULL;
3075 }
3076
3077 hist_field = find_var_field(hist_data, var_name);
3078
3079 return hist_field;
3080 }
3081
__update_field_vars(struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * rec,struct field_var ** field_vars,unsigned int n_field_vars,unsigned int field_var_str_start)3082 static inline void __update_field_vars(struct tracing_map_elt *elt,
3083 struct ring_buffer_event *rbe,
3084 void *rec,
3085 struct field_var **field_vars,
3086 unsigned int n_field_vars,
3087 unsigned int field_var_str_start)
3088 {
3089 struct hist_elt_data *elt_data = elt->private_data;
3090 unsigned int i, j, var_idx;
3091 u64 var_val;
3092
3093 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) {
3094 struct field_var *field_var = field_vars[i];
3095 struct hist_field *var = field_var->var;
3096 struct hist_field *val = field_var->val;
3097
3098 var_val = val->fn(val, elt, rbe, rec);
3099 var_idx = var->var.idx;
3100
3101 if (val->flags & HIST_FIELD_FL_STRING) {
3102 char *str = elt_data->field_var_str[j++];
3103 char *val_str = (char *)(uintptr_t)var_val;
3104
3105 strscpy(str, val_str, STR_VAR_LEN_MAX);
3106 var_val = (u64)(uintptr_t)str;
3107 }
3108 tracing_map_set_var(elt, var_idx, var_val);
3109 }
3110 }
3111
update_field_vars(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * rec)3112 static void update_field_vars(struct hist_trigger_data *hist_data,
3113 struct tracing_map_elt *elt,
3114 struct ring_buffer_event *rbe,
3115 void *rec)
3116 {
3117 __update_field_vars(elt, rbe, rec, hist_data->field_vars,
3118 hist_data->n_field_vars, 0);
3119 }
3120
update_max_vars(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct ring_buffer_event * rbe,void * rec)3121 static void update_max_vars(struct hist_trigger_data *hist_data,
3122 struct tracing_map_elt *elt,
3123 struct ring_buffer_event *rbe,
3124 void *rec)
3125 {
3126 __update_field_vars(elt, rbe, rec, hist_data->max_vars,
3127 hist_data->n_max_vars, hist_data->n_field_var_str);
3128 }
3129
create_var(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * name,int size,const char * type)3130 static struct hist_field *create_var(struct hist_trigger_data *hist_data,
3131 struct trace_event_file *file,
3132 char *name, int size, const char *type)
3133 {
3134 struct hist_field *var;
3135 int idx;
3136
3137 if (find_var(hist_data, file, name) && !hist_data->remove) {
3138 var = ERR_PTR(-EINVAL);
3139 goto out;
3140 }
3141
3142 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
3143 if (!var) {
3144 var = ERR_PTR(-ENOMEM);
3145 goto out;
3146 }
3147
3148 idx = tracing_map_add_var(hist_data->map);
3149 if (idx < 0) {
3150 kfree(var);
3151 var = ERR_PTR(-EINVAL);
3152 goto out;
3153 }
3154
3155 var->flags = HIST_FIELD_FL_VAR;
3156 var->var.idx = idx;
3157 var->var.hist_data = var->hist_data = hist_data;
3158 var->size = size;
3159 var->var.name = kstrdup(name, GFP_KERNEL);
3160 var->type = kstrdup(type, GFP_KERNEL);
3161 if (!var->var.name || !var->type) {
3162 kfree(var->var.name);
3163 kfree(var->type);
3164 kfree(var);
3165 var = ERR_PTR(-ENOMEM);
3166 }
3167 out:
3168 return var;
3169 }
3170
create_field_var(struct hist_trigger_data * hist_data,struct trace_event_file * file,char * field_name)3171 static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
3172 struct trace_event_file *file,
3173 char *field_name)
3174 {
3175 struct hist_field *val = NULL, *var = NULL;
3176 unsigned long flags = HIST_FIELD_FL_VAR;
3177 struct field_var *field_var;
3178 int ret = 0;
3179
3180 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) {
3181 hist_err("Too many field variables defined: ", field_name);
3182 ret = -EINVAL;
3183 goto err;
3184 }
3185
3186 val = parse_atom(hist_data, file, field_name, &flags, NULL);
3187 if (IS_ERR(val)) {
3188 hist_err("Couldn't parse field variable: ", field_name);
3189 ret = PTR_ERR(val);
3190 goto err;
3191 }
3192
3193 var = create_var(hist_data, file, field_name, val->size, val->type);
3194 if (IS_ERR(var)) {
3195 hist_err("Couldn't create or find variable: ", field_name);
3196 kfree(val);
3197 ret = PTR_ERR(var);
3198 goto err;
3199 }
3200
3201 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL);
3202 if (!field_var) {
3203 kfree(val);
3204 kfree(var);
3205 ret = -ENOMEM;
3206 goto err;
3207 }
3208
3209 field_var->var = var;
3210 field_var->val = val;
3211 out:
3212 return field_var;
3213 err:
3214 field_var = ERR_PTR(ret);
3215 goto out;
3216 }
3217
3218 /**
3219 * create_target_field_var - Automatically create a variable for a field
3220 * @target_hist_data: The target hist trigger
3221 * @subsys_name: Optional subsystem name
3222 * @event_name: Optional event name
3223 * @var_name: The name of the field (and the resulting variable)
3224 *
3225 * Hist trigger actions fetch data from variables, not directly from
3226 * events. However, for convenience, users are allowed to directly
3227 * specify an event field in an action, which will be automatically
3228 * converted into a variable on their behalf.
3229
3230 * This function creates a field variable with the name var_name on
3231 * the hist trigger currently being defined on the target event. If
3232 * subsys_name and event_name are specified, this function simply
3233 * verifies that they do in fact match the target event subsystem and
3234 * event name.
3235 *
3236 * Return: The variable created for the field.
3237 */
3238 static struct field_var *
create_target_field_var(struct hist_trigger_data * target_hist_data,char * subsys_name,char * event_name,char * var_name)3239 create_target_field_var(struct hist_trigger_data *target_hist_data,
3240 char *subsys_name, char *event_name, char *var_name)
3241 {
3242 struct trace_event_file *file = target_hist_data->event_file;
3243
3244 if (subsys_name) {
3245 struct trace_event_call *call;
3246
3247 if (!event_name)
3248 return NULL;
3249
3250 call = file->event_call;
3251
3252 if (strcmp(subsys_name, call->class->system) != 0)
3253 return NULL;
3254
3255 if (strcmp(event_name, trace_event_name(call)) != 0)
3256 return NULL;
3257 }
3258
3259 return create_field_var(target_hist_data, file, var_name);
3260 }
3261
onmax_print(struct seq_file * m,struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,struct action_data * data)3262 static void onmax_print(struct seq_file *m,
3263 struct hist_trigger_data *hist_data,
3264 struct tracing_map_elt *elt,
3265 struct action_data *data)
3266 {
3267 unsigned int i, save_var_idx, max_idx = data->onmax.max_var->var.idx;
3268
3269 seq_printf(m, "\n\tmax: %10llu", tracing_map_read_var(elt, max_idx));
3270
3271 for (i = 0; i < hist_data->n_max_vars; i++) {
3272 struct hist_field *save_val = hist_data->max_vars[i]->val;
3273 struct hist_field *save_var = hist_data->max_vars[i]->var;
3274 u64 val;
3275
3276 save_var_idx = save_var->var.idx;
3277
3278 val = tracing_map_read_var(elt, save_var_idx);
3279
3280 if (save_val->flags & HIST_FIELD_FL_STRING) {
3281 seq_printf(m, " %s: %-32s", save_var->var.name,
3282 (char *)(uintptr_t)(val));
3283 } else
3284 seq_printf(m, " %s: %10llu", save_var->var.name, val);
3285 }
3286 }
3287
onmax_save(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,struct action_data * data,u64 * var_ref_vals)3288 static void onmax_save(struct hist_trigger_data *hist_data,
3289 struct tracing_map_elt *elt, void *rec,
3290 struct ring_buffer_event *rbe,
3291 struct action_data *data, u64 *var_ref_vals)
3292 {
3293 unsigned int max_idx = data->onmax.max_var->var.idx;
3294 unsigned int max_var_ref_idx = data->onmax.max_var_ref_idx;
3295
3296 u64 var_val, max_val;
3297
3298 var_val = var_ref_vals[max_var_ref_idx];
3299 max_val = tracing_map_read_var(elt, max_idx);
3300
3301 if (var_val <= max_val)
3302 return;
3303
3304 tracing_map_set_var(elt, max_idx, var_val);
3305
3306 update_max_vars(hist_data, elt, rbe, rec);
3307 }
3308
onmax_destroy(struct action_data * data)3309 static void onmax_destroy(struct action_data *data)
3310 {
3311 unsigned int i;
3312
3313 destroy_hist_field(data->onmax.max_var, 0);
3314 destroy_hist_field(data->onmax.var, 0);
3315
3316 kfree(data->onmax.var_str);
3317 kfree(data->onmax.fn_name);
3318
3319 for (i = 0; i < data->n_params; i++)
3320 kfree(data->params[i]);
3321
3322 kfree(data);
3323 }
3324
onmax_create(struct hist_trigger_data * hist_data,struct action_data * data)3325 static int onmax_create(struct hist_trigger_data *hist_data,
3326 struct action_data *data)
3327 {
3328 struct trace_event_file *file = hist_data->event_file;
3329 struct hist_field *var_field, *ref_field, *max_var;
3330 unsigned int var_ref_idx = hist_data->n_var_refs;
3331 struct field_var *field_var;
3332 char *onmax_var_str, *param;
3333 unsigned long flags;
3334 unsigned int i;
3335 int ret = 0;
3336
3337 onmax_var_str = data->onmax.var_str;
3338 if (onmax_var_str[0] != '$') {
3339 hist_err("onmax: For onmax(x), x must be a variable: ", onmax_var_str);
3340 return -EINVAL;
3341 }
3342 onmax_var_str++;
3343
3344 var_field = find_target_event_var(hist_data, NULL, NULL, onmax_var_str);
3345 if (!var_field) {
3346 hist_err("onmax: Couldn't find onmax variable: ", onmax_var_str);
3347 return -EINVAL;
3348 }
3349
3350 flags = HIST_FIELD_FL_VAR_REF;
3351 ref_field = create_hist_field(hist_data, NULL, flags, NULL);
3352 if (!ref_field)
3353 return -ENOMEM;
3354
3355 if (init_var_ref(ref_field, var_field, NULL, NULL)) {
3356 destroy_hist_field(ref_field, 0);
3357 ret = -ENOMEM;
3358 goto out;
3359 }
3360 hist_data->var_refs[hist_data->n_var_refs] = ref_field;
3361 ref_field->var_ref_idx = hist_data->n_var_refs++;
3362 data->onmax.var = ref_field;
3363
3364 data->fn = onmax_save;
3365 data->onmax.max_var_ref_idx = var_ref_idx;
3366 max_var = create_var(hist_data, file, "max", sizeof(u64), "u64");
3367 if (IS_ERR(max_var)) {
3368 hist_err("onmax: Couldn't create onmax variable: ", "max");
3369 ret = PTR_ERR(max_var);
3370 goto out;
3371 }
3372 data->onmax.max_var = max_var;
3373
3374 for (i = 0; i < data->n_params; i++) {
3375 param = kstrdup(data->params[i], GFP_KERNEL);
3376 if (!param) {
3377 ret = -ENOMEM;
3378 goto out;
3379 }
3380
3381 field_var = create_target_field_var(hist_data, NULL, NULL, param);
3382 if (IS_ERR(field_var)) {
3383 hist_err("onmax: Couldn't create field variable: ", param);
3384 ret = PTR_ERR(field_var);
3385 kfree(param);
3386 goto out;
3387 }
3388
3389 hist_data->max_vars[hist_data->n_max_vars++] = field_var;
3390 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3391 hist_data->n_max_var_str++;
3392
3393 kfree(param);
3394 }
3395 out:
3396 return ret;
3397 }
3398
parse_action_params(char * params,struct action_data * data)3399 static int parse_action_params(char *params, struct action_data *data)
3400 {
3401 char *param, *saved_param;
3402 int ret = 0;
3403
3404 while (params) {
3405 if (data->n_params >= SYNTH_FIELDS_MAX)
3406 goto out;
3407
3408 param = strsep(¶ms, ",");
3409 if (!param) {
3410 ret = -EINVAL;
3411 goto out;
3412 }
3413
3414 param = strstrip(param);
3415 if (strlen(param) < 2) {
3416 hist_err("Invalid action param: ", param);
3417 ret = -EINVAL;
3418 goto out;
3419 }
3420
3421 saved_param = kstrdup(param, GFP_KERNEL);
3422 if (!saved_param) {
3423 ret = -ENOMEM;
3424 goto out;
3425 }
3426
3427 data->params[data->n_params++] = saved_param;
3428 }
3429 out:
3430 return ret;
3431 }
3432
onmax_parse(char * str)3433 static struct action_data *onmax_parse(char *str)
3434 {
3435 char *onmax_fn_name, *onmax_var_str;
3436 struct action_data *data;
3437 int ret = -EINVAL;
3438
3439 data = kzalloc(sizeof(*data), GFP_KERNEL);
3440 if (!data)
3441 return ERR_PTR(-ENOMEM);
3442
3443 onmax_var_str = strsep(&str, ")");
3444 if (!onmax_var_str || !str) {
3445 ret = -EINVAL;
3446 goto free;
3447 }
3448
3449 data->onmax.var_str = kstrdup(onmax_var_str, GFP_KERNEL);
3450 if (!data->onmax.var_str) {
3451 ret = -ENOMEM;
3452 goto free;
3453 }
3454
3455 strsep(&str, ".");
3456 if (!str)
3457 goto free;
3458
3459 onmax_fn_name = strsep(&str, "(");
3460 if (!onmax_fn_name || !str)
3461 goto free;
3462
3463 if (strncmp(onmax_fn_name, "save", strlen("save")) == 0) {
3464 char *params = strsep(&str, ")");
3465
3466 if (!params) {
3467 ret = -EINVAL;
3468 goto free;
3469 }
3470
3471 ret = parse_action_params(params, data);
3472 if (ret)
3473 goto free;
3474 } else
3475 goto free;
3476
3477 data->onmax.fn_name = kstrdup(onmax_fn_name, GFP_KERNEL);
3478 if (!data->onmax.fn_name) {
3479 ret = -ENOMEM;
3480 goto free;
3481 }
3482 out:
3483 return data;
3484 free:
3485 onmax_destroy(data);
3486 data = ERR_PTR(ret);
3487 goto out;
3488 }
3489
onmatch_destroy(struct action_data * data)3490 static void onmatch_destroy(struct action_data *data)
3491 {
3492 unsigned int i;
3493
3494 mutex_lock(&synth_event_mutex);
3495
3496 kfree(data->onmatch.match_event);
3497 kfree(data->onmatch.match_event_system);
3498 kfree(data->onmatch.synth_event_name);
3499
3500 for (i = 0; i < data->n_params; i++)
3501 kfree(data->params[i]);
3502
3503 if (data->onmatch.synth_event)
3504 data->onmatch.synth_event->ref--;
3505
3506 kfree(data);
3507
3508 mutex_unlock(&synth_event_mutex);
3509 }
3510
destroy_field_var(struct field_var * field_var)3511 static void destroy_field_var(struct field_var *field_var)
3512 {
3513 if (!field_var)
3514 return;
3515
3516 destroy_hist_field(field_var->var, 0);
3517 destroy_hist_field(field_var->val, 0);
3518
3519 kfree(field_var);
3520 }
3521
destroy_field_vars(struct hist_trigger_data * hist_data)3522 static void destroy_field_vars(struct hist_trigger_data *hist_data)
3523 {
3524 unsigned int i;
3525
3526 for (i = 0; i < hist_data->n_field_vars; i++)
3527 destroy_field_var(hist_data->field_vars[i]);
3528 }
3529
save_field_var(struct hist_trigger_data * hist_data,struct field_var * field_var)3530 static void save_field_var(struct hist_trigger_data *hist_data,
3531 struct field_var *field_var)
3532 {
3533 hist_data->field_vars[hist_data->n_field_vars++] = field_var;
3534
3535 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3536 hist_data->n_field_var_str++;
3537 }
3538
3539
destroy_synth_var_refs(struct hist_trigger_data * hist_data)3540 static void destroy_synth_var_refs(struct hist_trigger_data *hist_data)
3541 {
3542 unsigned int i;
3543
3544 for (i = 0; i < hist_data->n_synth_var_refs; i++)
3545 destroy_hist_field(hist_data->synth_var_refs[i], 0);
3546 }
3547
save_synth_var_ref(struct hist_trigger_data * hist_data,struct hist_field * var_ref)3548 static void save_synth_var_ref(struct hist_trigger_data *hist_data,
3549 struct hist_field *var_ref)
3550 {
3551 hist_data->synth_var_refs[hist_data->n_synth_var_refs++] = var_ref;
3552
3553 hist_data->var_refs[hist_data->n_var_refs] = var_ref;
3554 var_ref->var_ref_idx = hist_data->n_var_refs++;
3555 }
3556
check_synth_field(struct synth_event * event,struct hist_field * hist_field,unsigned int field_pos)3557 static int check_synth_field(struct synth_event *event,
3558 struct hist_field *hist_field,
3559 unsigned int field_pos)
3560 {
3561 struct synth_field *field;
3562
3563 if (field_pos >= event->n_fields)
3564 return -EINVAL;
3565
3566 field = event->fields[field_pos];
3567
3568 if (strcmp(field->type, hist_field->type) != 0)
3569 return -EINVAL;
3570
3571 return 0;
3572 }
3573
3574 static struct hist_field *
onmatch_find_var(struct hist_trigger_data * hist_data,struct action_data * data,char * system,char * event,char * var)3575 onmatch_find_var(struct hist_trigger_data *hist_data, struct action_data *data,
3576 char *system, char *event, char *var)
3577 {
3578 struct hist_field *hist_field;
3579
3580 var++; /* skip '$' */
3581
3582 hist_field = find_target_event_var(hist_data, system, event, var);
3583 if (!hist_field) {
3584 if (!system) {
3585 system = data->onmatch.match_event_system;
3586 event = data->onmatch.match_event;
3587 }
3588
3589 hist_field = find_event_var(hist_data, system, event, var);
3590 }
3591
3592 if (!hist_field)
3593 hist_err_event("onmatch: Couldn't find onmatch param: $", system, event, var);
3594
3595 return hist_field;
3596 }
3597
3598 static struct hist_field *
onmatch_create_field_var(struct hist_trigger_data * hist_data,struct action_data * data,char * system,char * event,char * var)3599 onmatch_create_field_var(struct hist_trigger_data *hist_data,
3600 struct action_data *data, char *system,
3601 char *event, char *var)
3602 {
3603 struct hist_field *hist_field = NULL;
3604 struct field_var *field_var;
3605
3606 /*
3607 * First try to create a field var on the target event (the
3608 * currently being defined). This will create a variable for
3609 * unqualified fields on the target event, or if qualified,
3610 * target fields that have qualified names matching the target.
3611 */
3612 field_var = create_target_field_var(hist_data, system, event, var);
3613
3614 if (field_var && !IS_ERR(field_var)) {
3615 save_field_var(hist_data, field_var);
3616 hist_field = field_var->var;
3617 } else {
3618 field_var = NULL;
3619 /*
3620 * If no explicit system.event is specfied, default to
3621 * looking for fields on the onmatch(system.event.xxx)
3622 * event.
3623 */
3624 if (!system) {
3625 system = data->onmatch.match_event_system;
3626 event = data->onmatch.match_event;
3627 }
3628
3629 /*
3630 * At this point, we're looking at a field on another
3631 * event. Because we can't modify a hist trigger on
3632 * another event to add a variable for a field, we need
3633 * to create a new trigger on that event and create the
3634 * variable at the same time.
3635 */
3636 hist_field = create_field_var_hist(hist_data, system, event, var);
3637 if (IS_ERR(hist_field))
3638 goto free;
3639 }
3640 out:
3641 return hist_field;
3642 free:
3643 destroy_field_var(field_var);
3644 hist_field = NULL;
3645 goto out;
3646 }
3647
onmatch_create(struct hist_trigger_data * hist_data,struct trace_event_file * file,struct action_data * data)3648 static int onmatch_create(struct hist_trigger_data *hist_data,
3649 struct trace_event_file *file,
3650 struct action_data *data)
3651 {
3652 char *event_name, *param, *system = NULL;
3653 struct hist_field *hist_field, *var_ref;
3654 unsigned int i, var_ref_idx;
3655 unsigned int field_pos = 0;
3656 struct synth_event *event;
3657 int ret = 0;
3658
3659 mutex_lock(&synth_event_mutex);
3660 event = find_synth_event(data->onmatch.synth_event_name);
3661 if (!event) {
3662 hist_err("onmatch: Couldn't find synthetic event: ", data->onmatch.synth_event_name);
3663 mutex_unlock(&synth_event_mutex);
3664 return -EINVAL;
3665 }
3666 event->ref++;
3667 mutex_unlock(&synth_event_mutex);
3668
3669 var_ref_idx = hist_data->n_var_refs;
3670
3671 for (i = 0; i < data->n_params; i++) {
3672 char *p;
3673
3674 p = param = kstrdup(data->params[i], GFP_KERNEL);
3675 if (!param) {
3676 ret = -ENOMEM;
3677 goto err;
3678 }
3679
3680 system = strsep(¶m, ".");
3681 if (!param) {
3682 param = (char *)system;
3683 system = event_name = NULL;
3684 } else {
3685 event_name = strsep(¶m, ".");
3686 if (!param) {
3687 kfree(p);
3688 ret = -EINVAL;
3689 goto err;
3690 }
3691 }
3692
3693 if (param[0] == '$')
3694 hist_field = onmatch_find_var(hist_data, data, system,
3695 event_name, param);
3696 else
3697 hist_field = onmatch_create_field_var(hist_data, data,
3698 system,
3699 event_name,
3700 param);
3701
3702 if (!hist_field) {
3703 kfree(p);
3704 ret = -EINVAL;
3705 goto err;
3706 }
3707
3708 if (check_synth_field(event, hist_field, field_pos) == 0) {
3709 var_ref = create_var_ref(hist_field, system, event_name);
3710 if (!var_ref) {
3711 kfree(p);
3712 ret = -ENOMEM;
3713 goto err;
3714 }
3715
3716 save_synth_var_ref(hist_data, var_ref);
3717 field_pos++;
3718 kfree(p);
3719 continue;
3720 }
3721
3722 hist_err_event("onmatch: Param type doesn't match synthetic event field type: ",
3723 system, event_name, param);
3724 kfree(p);
3725 ret = -EINVAL;
3726 goto err;
3727 }
3728
3729 if (field_pos != event->n_fields) {
3730 hist_err("onmatch: Param count doesn't match synthetic event field count: ", event->name);
3731 ret = -EINVAL;
3732 goto err;
3733 }
3734
3735 data->fn = action_trace;
3736 data->onmatch.synth_event = event;
3737 data->onmatch.var_ref_idx = var_ref_idx;
3738 out:
3739 return ret;
3740 err:
3741 mutex_lock(&synth_event_mutex);
3742 event->ref--;
3743 mutex_unlock(&synth_event_mutex);
3744
3745 goto out;
3746 }
3747
onmatch_parse(struct trace_array * tr,char * str)3748 static struct action_data *onmatch_parse(struct trace_array *tr, char *str)
3749 {
3750 char *match_event, *match_event_system;
3751 char *synth_event_name, *params;
3752 struct action_data *data;
3753 int ret = -EINVAL;
3754
3755 data = kzalloc(sizeof(*data), GFP_KERNEL);
3756 if (!data)
3757 return ERR_PTR(-ENOMEM);
3758
3759 match_event = strsep(&str, ")");
3760 if (!match_event || !str) {
3761 hist_err("onmatch: Missing closing paren: ", match_event);
3762 goto free;
3763 }
3764
3765 match_event_system = strsep(&match_event, ".");
3766 if (!match_event) {
3767 hist_err("onmatch: Missing subsystem for match event: ", match_event_system);
3768 goto free;
3769 }
3770
3771 if (IS_ERR(event_file(tr, match_event_system, match_event))) {
3772 hist_err_event("onmatch: Invalid subsystem or event name: ",
3773 match_event_system, match_event, NULL);
3774 goto free;
3775 }
3776
3777 data->onmatch.match_event = kstrdup(match_event, GFP_KERNEL);
3778 if (!data->onmatch.match_event) {
3779 ret = -ENOMEM;
3780 goto free;
3781 }
3782
3783 data->onmatch.match_event_system = kstrdup(match_event_system, GFP_KERNEL);
3784 if (!data->onmatch.match_event_system) {
3785 ret = -ENOMEM;
3786 goto free;
3787 }
3788
3789 strsep(&str, ".");
3790 if (!str) {
3791 hist_err("onmatch: Missing . after onmatch(): ", str);
3792 goto free;
3793 }
3794
3795 synth_event_name = strsep(&str, "(");
3796 if (!synth_event_name || !str) {
3797 hist_err("onmatch: Missing opening paramlist paren: ", synth_event_name);
3798 goto free;
3799 }
3800
3801 data->onmatch.synth_event_name = kstrdup(synth_event_name, GFP_KERNEL);
3802 if (!data->onmatch.synth_event_name) {
3803 ret = -ENOMEM;
3804 goto free;
3805 }
3806
3807 params = strsep(&str, ")");
3808 if (!params || !str || (str && strlen(str))) {
3809 hist_err("onmatch: Missing closing paramlist paren: ", params);
3810 goto free;
3811 }
3812
3813 ret = parse_action_params(params, data);
3814 if (ret)
3815 goto free;
3816 out:
3817 return data;
3818 free:
3819 onmatch_destroy(data);
3820 data = ERR_PTR(ret);
3821 goto out;
3822 }
3823
create_hitcount_val(struct hist_trigger_data * hist_data)3824 static int create_hitcount_val(struct hist_trigger_data *hist_data)
3825 {
3826 hist_data->fields[HITCOUNT_IDX] =
3827 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL);
3828 if (!hist_data->fields[HITCOUNT_IDX])
3829 return -ENOMEM;
3830
3831 hist_data->n_vals++;
3832 hist_data->n_fields++;
3833
3834 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
3835 return -EINVAL;
3836
3837 return 0;
3838 }
3839
__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)3840 static int __create_val_field(struct hist_trigger_data *hist_data,
3841 unsigned int val_idx,
3842 struct trace_event_file *file,
3843 char *var_name, char *field_str,
3844 unsigned long flags)
3845 {
3846 struct hist_field *hist_field;
3847 int ret = 0;
3848
3849 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0);
3850 if (IS_ERR(hist_field)) {
3851 ret = PTR_ERR(hist_field);
3852 goto out;
3853 }
3854
3855 hist_data->fields[val_idx] = hist_field;
3856
3857 ++hist_data->n_vals;
3858 ++hist_data->n_fields;
3859
3860 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3861 ret = -EINVAL;
3862 out:
3863 return ret;
3864 }
3865
create_val_field(struct hist_trigger_data * hist_data,unsigned int val_idx,struct trace_event_file * file,char * field_str)3866 static int create_val_field(struct hist_trigger_data *hist_data,
3867 unsigned int val_idx,
3868 struct trace_event_file *file,
3869 char *field_str)
3870 {
3871 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
3872 return -EINVAL;
3873
3874 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
3875 }
3876
create_var_field(struct hist_trigger_data * hist_data,unsigned int val_idx,struct trace_event_file * file,char * var_name,char * expr_str)3877 static int create_var_field(struct hist_trigger_data *hist_data,
3878 unsigned int val_idx,
3879 struct trace_event_file *file,
3880 char *var_name, char *expr_str)
3881 {
3882 unsigned long flags = 0;
3883
3884 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3885 return -EINVAL;
3886
3887 if (find_var(hist_data, file, var_name) && !hist_data->remove) {
3888 hist_err("Variable already defined: ", var_name);
3889 return -EINVAL;
3890 }
3891
3892 flags |= HIST_FIELD_FL_VAR;
3893 hist_data->n_vars++;
3894 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX))
3895 return -EINVAL;
3896
3897 return __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags);
3898 }
3899
create_val_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)3900 static int create_val_fields(struct hist_trigger_data *hist_data,
3901 struct trace_event_file *file)
3902 {
3903 char *fields_str, *field_str;
3904 unsigned int i, j = 1;
3905 int ret;
3906
3907 ret = create_hitcount_val(hist_data);
3908 if (ret)
3909 goto out;
3910
3911 fields_str = hist_data->attrs->vals_str;
3912 if (!fields_str)
3913 goto out;
3914
3915 strsep(&fields_str, "=");
3916 if (!fields_str)
3917 goto out;
3918
3919 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
3920 j < TRACING_MAP_VALS_MAX; i++) {
3921 field_str = strsep(&fields_str, ",");
3922 if (!field_str)
3923 break;
3924
3925 if (strcmp(field_str, "hitcount") == 0)
3926 continue;
3927
3928 ret = create_val_field(hist_data, j++, file, field_str);
3929 if (ret)
3930 goto out;
3931 }
3932
3933 if (fields_str && (strcmp(fields_str, "hitcount") != 0))
3934 ret = -EINVAL;
3935 out:
3936 return ret;
3937 }
3938
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)3939 static int create_key_field(struct hist_trigger_data *hist_data,
3940 unsigned int key_idx,
3941 unsigned int key_offset,
3942 struct trace_event_file *file,
3943 char *field_str)
3944 {
3945 struct hist_field *hist_field = NULL;
3946
3947 unsigned long flags = 0;
3948 unsigned int key_size;
3949 int ret = 0;
3950
3951 if (WARN_ON(key_idx >= HIST_FIELDS_MAX))
3952 return -EINVAL;
3953
3954 flags |= HIST_FIELD_FL_KEY;
3955
3956 if (strcmp(field_str, "stacktrace") == 0) {
3957 flags |= HIST_FIELD_FL_STACKTRACE;
3958 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH;
3959 hist_field = create_hist_field(hist_data, NULL, flags, NULL);
3960 } else {
3961 hist_field = parse_expr(hist_data, file, field_str, flags,
3962 NULL, 0);
3963 if (IS_ERR(hist_field)) {
3964 ret = PTR_ERR(hist_field);
3965 goto out;
3966 }
3967
3968 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) {
3969 hist_err("Using variable references as keys not supported: ", field_str);
3970 destroy_hist_field(hist_field, 0);
3971 ret = -EINVAL;
3972 goto out;
3973 }
3974
3975 key_size = hist_field->size;
3976 }
3977
3978 hist_data->fields[key_idx] = hist_field;
3979
3980 key_size = ALIGN(key_size, sizeof(u64));
3981 hist_data->fields[key_idx]->size = key_size;
3982 hist_data->fields[key_idx]->offset = key_offset;
3983
3984 hist_data->key_size += key_size;
3985
3986 if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
3987 ret = -EINVAL;
3988 goto out;
3989 }
3990
3991 hist_data->n_keys++;
3992 hist_data->n_fields++;
3993
3994 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX))
3995 return -EINVAL;
3996
3997 ret = key_size;
3998 out:
3999 return ret;
4000 }
4001
create_key_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)4002 static int create_key_fields(struct hist_trigger_data *hist_data,
4003 struct trace_event_file *file)
4004 {
4005 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals;
4006 char *fields_str, *field_str;
4007 int ret = -EINVAL;
4008
4009 fields_str = hist_data->attrs->keys_str;
4010 if (!fields_str)
4011 goto out;
4012
4013 strsep(&fields_str, "=");
4014 if (!fields_str)
4015 goto out;
4016
4017 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
4018 field_str = strsep(&fields_str, ",");
4019 if (!field_str)
4020 break;
4021 ret = create_key_field(hist_data, i, key_offset,
4022 file, field_str);
4023 if (ret < 0)
4024 goto out;
4025 key_offset += ret;
4026 }
4027 if (fields_str) {
4028 ret = -EINVAL;
4029 goto out;
4030 }
4031 ret = 0;
4032 out:
4033 return ret;
4034 }
4035
create_var_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)4036 static int create_var_fields(struct hist_trigger_data *hist_data,
4037 struct trace_event_file *file)
4038 {
4039 unsigned int i, j = hist_data->n_vals;
4040 int ret = 0;
4041
4042 unsigned int n_vars = hist_data->attrs->var_defs.n_vars;
4043
4044 for (i = 0; i < n_vars; i++) {
4045 char *var_name = hist_data->attrs->var_defs.name[i];
4046 char *expr = hist_data->attrs->var_defs.expr[i];
4047
4048 ret = create_var_field(hist_data, j++, file, var_name, expr);
4049 if (ret)
4050 goto out;
4051 }
4052 out:
4053 return ret;
4054 }
4055
free_var_defs(struct hist_trigger_data * hist_data)4056 static void free_var_defs(struct hist_trigger_data *hist_data)
4057 {
4058 unsigned int i;
4059
4060 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
4061 kfree(hist_data->attrs->var_defs.name[i]);
4062 kfree(hist_data->attrs->var_defs.expr[i]);
4063 }
4064
4065 hist_data->attrs->var_defs.n_vars = 0;
4066 }
4067
parse_var_defs(struct hist_trigger_data * hist_data)4068 static int parse_var_defs(struct hist_trigger_data *hist_data)
4069 {
4070 char *s, *str, *var_name, *field_str;
4071 unsigned int i, j, n_vars = 0;
4072 int ret = 0;
4073
4074 for (i = 0; i < hist_data->attrs->n_assignments; i++) {
4075 str = hist_data->attrs->assignment_str[i];
4076 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) {
4077 field_str = strsep(&str, ",");
4078 if (!field_str)
4079 break;
4080
4081 var_name = strsep(&field_str, "=");
4082 if (!var_name || !field_str) {
4083 hist_err("Malformed assignment: ", var_name);
4084 ret = -EINVAL;
4085 goto free;
4086 }
4087
4088 if (n_vars == TRACING_MAP_VARS_MAX) {
4089 hist_err("Too many variables defined: ", var_name);
4090 ret = -EINVAL;
4091 goto free;
4092 }
4093
4094 s = kstrdup(var_name, GFP_KERNEL);
4095 if (!s) {
4096 ret = -ENOMEM;
4097 goto free;
4098 }
4099 hist_data->attrs->var_defs.name[n_vars] = s;
4100
4101 s = kstrdup(field_str, GFP_KERNEL);
4102 if (!s) {
4103 kfree(hist_data->attrs->var_defs.name[n_vars]);
4104 ret = -ENOMEM;
4105 goto free;
4106 }
4107 hist_data->attrs->var_defs.expr[n_vars++] = s;
4108
4109 hist_data->attrs->var_defs.n_vars = n_vars;
4110 }
4111 }
4112
4113 return ret;
4114 free:
4115 free_var_defs(hist_data);
4116
4117 return ret;
4118 }
4119
create_hist_fields(struct hist_trigger_data * hist_data,struct trace_event_file * file)4120 static int create_hist_fields(struct hist_trigger_data *hist_data,
4121 struct trace_event_file *file)
4122 {
4123 int ret;
4124
4125 ret = parse_var_defs(hist_data);
4126 if (ret)
4127 goto out;
4128
4129 ret = create_val_fields(hist_data, file);
4130 if (ret)
4131 goto out;
4132
4133 ret = create_var_fields(hist_data, file);
4134 if (ret)
4135 goto out;
4136
4137 ret = create_key_fields(hist_data, file);
4138 if (ret)
4139 goto out;
4140 out:
4141 free_var_defs(hist_data);
4142
4143 return ret;
4144 }
4145
is_descending(const char * str)4146 static int is_descending(const char *str)
4147 {
4148 if (!str)
4149 return 0;
4150
4151 if (strcmp(str, "descending") == 0)
4152 return 1;
4153
4154 if (strcmp(str, "ascending") == 0)
4155 return 0;
4156
4157 return -EINVAL;
4158 }
4159
create_sort_keys(struct hist_trigger_data * hist_data)4160 static int create_sort_keys(struct hist_trigger_data *hist_data)
4161 {
4162 char *fields_str = hist_data->attrs->sort_key_str;
4163 struct tracing_map_sort_key *sort_key;
4164 int descending, ret = 0;
4165 unsigned int i, j, k;
4166
4167 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
4168
4169 if (!fields_str)
4170 goto out;
4171
4172 strsep(&fields_str, "=");
4173 if (!fields_str) {
4174 ret = -EINVAL;
4175 goto out;
4176 }
4177
4178 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
4179 struct hist_field *hist_field;
4180 char *field_str, *field_name;
4181 const char *test_name;
4182
4183 sort_key = &hist_data->sort_keys[i];
4184
4185 field_str = strsep(&fields_str, ",");
4186 if (!field_str) {
4187 if (i == 0)
4188 ret = -EINVAL;
4189 break;
4190 }
4191
4192 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) {
4193 ret = -EINVAL;
4194 break;
4195 }
4196
4197 field_name = strsep(&field_str, ".");
4198 if (!field_name) {
4199 ret = -EINVAL;
4200 break;
4201 }
4202
4203 if (strcmp(field_name, "hitcount") == 0) {
4204 descending = is_descending(field_str);
4205 if (descending < 0) {
4206 ret = descending;
4207 break;
4208 }
4209 sort_key->descending = descending;
4210 continue;
4211 }
4212
4213 for (j = 1, k = 1; j < hist_data->n_fields; j++) {
4214 unsigned int idx;
4215
4216 hist_field = hist_data->fields[j];
4217 if (hist_field->flags & HIST_FIELD_FL_VAR)
4218 continue;
4219
4220 idx = k++;
4221
4222 test_name = hist_field_name(hist_field, 0);
4223
4224 if (strcmp(field_name, test_name) == 0) {
4225 sort_key->field_idx = idx;
4226 descending = is_descending(field_str);
4227 if (descending < 0) {
4228 ret = descending;
4229 goto out;
4230 }
4231 sort_key->descending = descending;
4232 break;
4233 }
4234 }
4235 if (j == hist_data->n_fields) {
4236 ret = -EINVAL;
4237 break;
4238 }
4239 }
4240
4241 hist_data->n_sort_keys = i;
4242 out:
4243 return ret;
4244 }
4245
destroy_actions(struct hist_trigger_data * hist_data)4246 static void destroy_actions(struct hist_trigger_data *hist_data)
4247 {
4248 unsigned int i;
4249
4250 for (i = 0; i < hist_data->n_actions; i++) {
4251 struct action_data *data = hist_data->actions[i];
4252
4253 if (data->fn == action_trace)
4254 onmatch_destroy(data);
4255 else if (data->fn == onmax_save)
4256 onmax_destroy(data);
4257 else
4258 kfree(data);
4259 }
4260 }
4261
parse_actions(struct hist_trigger_data * hist_data)4262 static int parse_actions(struct hist_trigger_data *hist_data)
4263 {
4264 struct trace_array *tr = hist_data->event_file->tr;
4265 struct action_data *data;
4266 unsigned int i;
4267 int ret = 0;
4268 char *str;
4269
4270 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4271 str = hist_data->attrs->action_str[i];
4272
4273 if (strncmp(str, "onmatch(", strlen("onmatch(")) == 0) {
4274 char *action_str = str + strlen("onmatch(");
4275
4276 data = onmatch_parse(tr, action_str);
4277 if (IS_ERR(data)) {
4278 ret = PTR_ERR(data);
4279 break;
4280 }
4281 data->fn = action_trace;
4282 } else if (strncmp(str, "onmax(", strlen("onmax(")) == 0) {
4283 char *action_str = str + strlen("onmax(");
4284
4285 data = onmax_parse(action_str);
4286 if (IS_ERR(data)) {
4287 ret = PTR_ERR(data);
4288 break;
4289 }
4290 data->fn = onmax_save;
4291 } else {
4292 ret = -EINVAL;
4293 break;
4294 }
4295
4296 hist_data->actions[hist_data->n_actions++] = data;
4297 }
4298
4299 return ret;
4300 }
4301
create_actions(struct hist_trigger_data * hist_data,struct trace_event_file * file)4302 static int create_actions(struct hist_trigger_data *hist_data,
4303 struct trace_event_file *file)
4304 {
4305 struct action_data *data;
4306 unsigned int i;
4307 int ret = 0;
4308
4309 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4310 data = hist_data->actions[i];
4311
4312 if (data->fn == action_trace) {
4313 ret = onmatch_create(hist_data, file, data);
4314 if (ret)
4315 return ret;
4316 } else if (data->fn == onmax_save) {
4317 ret = onmax_create(hist_data, data);
4318 if (ret)
4319 return ret;
4320 }
4321 }
4322
4323 return ret;
4324 }
4325
print_actions(struct seq_file * m,struct hist_trigger_data * hist_data,struct tracing_map_elt * elt)4326 static void print_actions(struct seq_file *m,
4327 struct hist_trigger_data *hist_data,
4328 struct tracing_map_elt *elt)
4329 {
4330 unsigned int i;
4331
4332 for (i = 0; i < hist_data->n_actions; i++) {
4333 struct action_data *data = hist_data->actions[i];
4334
4335 if (data->fn == onmax_save)
4336 onmax_print(m, hist_data, elt, data);
4337 }
4338 }
4339
print_onmax_spec(struct seq_file * m,struct hist_trigger_data * hist_data,struct action_data * data)4340 static void print_onmax_spec(struct seq_file *m,
4341 struct hist_trigger_data *hist_data,
4342 struct action_data *data)
4343 {
4344 unsigned int i;
4345
4346 seq_puts(m, ":onmax(");
4347 seq_printf(m, "%s", data->onmax.var_str);
4348 seq_printf(m, ").%s(", data->onmax.fn_name);
4349
4350 for (i = 0; i < hist_data->n_max_vars; i++) {
4351 seq_printf(m, "%s", hist_data->max_vars[i]->var->var.name);
4352 if (i < hist_data->n_max_vars - 1)
4353 seq_puts(m, ",");
4354 }
4355 seq_puts(m, ")");
4356 }
4357
print_onmatch_spec(struct seq_file * m,struct hist_trigger_data * hist_data,struct action_data * data)4358 static void print_onmatch_spec(struct seq_file *m,
4359 struct hist_trigger_data *hist_data,
4360 struct action_data *data)
4361 {
4362 unsigned int i;
4363
4364 seq_printf(m, ":onmatch(%s.%s).", data->onmatch.match_event_system,
4365 data->onmatch.match_event);
4366
4367 seq_printf(m, "%s(", data->onmatch.synth_event->name);
4368
4369 for (i = 0; i < data->n_params; i++) {
4370 if (i)
4371 seq_puts(m, ",");
4372 seq_printf(m, "%s", data->params[i]);
4373 }
4374
4375 seq_puts(m, ")");
4376 }
4377
actions_match(struct hist_trigger_data * hist_data,struct hist_trigger_data * hist_data_test)4378 static bool actions_match(struct hist_trigger_data *hist_data,
4379 struct hist_trigger_data *hist_data_test)
4380 {
4381 unsigned int i, j;
4382
4383 if (hist_data->n_actions != hist_data_test->n_actions)
4384 return false;
4385
4386 for (i = 0; i < hist_data->n_actions; i++) {
4387 struct action_data *data = hist_data->actions[i];
4388 struct action_data *data_test = hist_data_test->actions[i];
4389
4390 if (data->fn != data_test->fn)
4391 return false;
4392
4393 if (data->n_params != data_test->n_params)
4394 return false;
4395
4396 for (j = 0; j < data->n_params; j++) {
4397 if (strcmp(data->params[j], data_test->params[j]) != 0)
4398 return false;
4399 }
4400
4401 if (data->fn == action_trace) {
4402 if (strcmp(data->onmatch.synth_event_name,
4403 data_test->onmatch.synth_event_name) != 0)
4404 return false;
4405 if (strcmp(data->onmatch.match_event_system,
4406 data_test->onmatch.match_event_system) != 0)
4407 return false;
4408 if (strcmp(data->onmatch.match_event,
4409 data_test->onmatch.match_event) != 0)
4410 return false;
4411 } else if (data->fn == onmax_save) {
4412 if (strcmp(data->onmax.var_str,
4413 data_test->onmax.var_str) != 0)
4414 return false;
4415 if (strcmp(data->onmax.fn_name,
4416 data_test->onmax.fn_name) != 0)
4417 return false;
4418 }
4419 }
4420
4421 return true;
4422 }
4423
4424
print_actions_spec(struct seq_file * m,struct hist_trigger_data * hist_data)4425 static void print_actions_spec(struct seq_file *m,
4426 struct hist_trigger_data *hist_data)
4427 {
4428 unsigned int i;
4429
4430 for (i = 0; i < hist_data->n_actions; i++) {
4431 struct action_data *data = hist_data->actions[i];
4432
4433 if (data->fn == action_trace)
4434 print_onmatch_spec(m, hist_data, data);
4435 else if (data->fn == onmax_save)
4436 print_onmax_spec(m, hist_data, data);
4437 }
4438 }
4439
destroy_field_var_hists(struct hist_trigger_data * hist_data)4440 static void destroy_field_var_hists(struct hist_trigger_data *hist_data)
4441 {
4442 unsigned int i;
4443
4444 for (i = 0; i < hist_data->n_field_var_hists; i++) {
4445 kfree(hist_data->field_var_hists[i]->cmd);
4446 kfree(hist_data->field_var_hists[i]);
4447 }
4448 }
4449
destroy_hist_data(struct hist_trigger_data * hist_data)4450 static void destroy_hist_data(struct hist_trigger_data *hist_data)
4451 {
4452 if (!hist_data)
4453 return;
4454
4455 destroy_hist_trigger_attrs(hist_data->attrs);
4456 destroy_hist_fields(hist_data);
4457 tracing_map_destroy(hist_data->map);
4458
4459 destroy_actions(hist_data);
4460 destroy_field_vars(hist_data);
4461 destroy_field_var_hists(hist_data);
4462 destroy_synth_var_refs(hist_data);
4463
4464 kfree(hist_data);
4465 }
4466
create_tracing_map_fields(struct hist_trigger_data * hist_data)4467 static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
4468 {
4469 struct tracing_map *map = hist_data->map;
4470 struct ftrace_event_field *field;
4471 struct hist_field *hist_field;
4472 int i, idx = 0;
4473
4474 for_each_hist_field(i, hist_data) {
4475 hist_field = hist_data->fields[i];
4476 if (hist_field->flags & HIST_FIELD_FL_KEY) {
4477 tracing_map_cmp_fn_t cmp_fn;
4478
4479 field = hist_field->field;
4480
4481 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
4482 cmp_fn = tracing_map_cmp_none;
4483 else if (!field)
4484 cmp_fn = tracing_map_cmp_num(hist_field->size,
4485 hist_field->is_signed);
4486 else if (is_string_field(field))
4487 cmp_fn = tracing_map_cmp_string;
4488 else
4489 cmp_fn = tracing_map_cmp_num(field->size,
4490 field->is_signed);
4491 idx = tracing_map_add_key_field(map,
4492 hist_field->offset,
4493 cmp_fn);
4494 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR))
4495 idx = tracing_map_add_sum_field(map);
4496
4497 if (idx < 0)
4498 return idx;
4499
4500 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4501 idx = tracing_map_add_var(map);
4502 if (idx < 0)
4503 return idx;
4504 hist_field->var.idx = idx;
4505 hist_field->var.hist_data = hist_data;
4506 }
4507 }
4508
4509 return 0;
4510 }
4511
4512 static struct hist_trigger_data *
create_hist_data(unsigned int map_bits,struct hist_trigger_attrs * attrs,struct trace_event_file * file,bool remove)4513 create_hist_data(unsigned int map_bits,
4514 struct hist_trigger_attrs *attrs,
4515 struct trace_event_file *file,
4516 bool remove)
4517 {
4518 const struct tracing_map_ops *map_ops = NULL;
4519 struct hist_trigger_data *hist_data;
4520 int ret = 0;
4521
4522 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL);
4523 if (!hist_data)
4524 return ERR_PTR(-ENOMEM);
4525
4526 hist_data->attrs = attrs;
4527 hist_data->remove = remove;
4528 hist_data->event_file = file;
4529
4530 ret = parse_actions(hist_data);
4531 if (ret)
4532 goto free;
4533
4534 ret = create_hist_fields(hist_data, file);
4535 if (ret)
4536 goto free;
4537
4538 ret = create_sort_keys(hist_data);
4539 if (ret)
4540 goto free;
4541
4542 map_ops = &hist_trigger_elt_data_ops;
4543
4544 hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
4545 map_ops, hist_data);
4546 if (IS_ERR(hist_data->map)) {
4547 ret = PTR_ERR(hist_data->map);
4548 hist_data->map = NULL;
4549 goto free;
4550 }
4551
4552 ret = create_tracing_map_fields(hist_data);
4553 if (ret)
4554 goto free;
4555 out:
4556 return hist_data;
4557 free:
4558 hist_data->attrs = NULL;
4559
4560 destroy_hist_data(hist_data);
4561
4562 hist_data = ERR_PTR(ret);
4563
4564 goto out;
4565 }
4566
hist_trigger_elt_update(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,u64 * var_ref_vals)4567 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
4568 struct tracing_map_elt *elt, void *rec,
4569 struct ring_buffer_event *rbe,
4570 u64 *var_ref_vals)
4571 {
4572 struct hist_elt_data *elt_data;
4573 struct hist_field *hist_field;
4574 unsigned int i, var_idx;
4575 u64 hist_val;
4576
4577 elt_data = elt->private_data;
4578 elt_data->var_ref_vals = var_ref_vals;
4579
4580 for_each_hist_val_field(i, hist_data) {
4581 hist_field = hist_data->fields[i];
4582 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4583 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4584 var_idx = hist_field->var.idx;
4585 tracing_map_set_var(elt, var_idx, hist_val);
4586 continue;
4587 }
4588 tracing_map_update_sum(elt, i, hist_val);
4589 }
4590
4591 for_each_hist_key_field(i, hist_data) {
4592 hist_field = hist_data->fields[i];
4593 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4594 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4595 var_idx = hist_field->var.idx;
4596 tracing_map_set_var(elt, var_idx, hist_val);
4597 }
4598 }
4599
4600 update_field_vars(hist_data, elt, rbe, rec);
4601 }
4602
add_to_key(char * compound_key,void * key,struct hist_field * key_field,void * rec)4603 static inline void add_to_key(char *compound_key, void *key,
4604 struct hist_field *key_field, void *rec)
4605 {
4606 size_t size = key_field->size;
4607
4608 if (key_field->flags & HIST_FIELD_FL_STRING) {
4609 struct ftrace_event_field *field;
4610
4611 field = key_field->field;
4612 if (field->filter_type == FILTER_DYN_STRING)
4613 size = *(u32 *)(rec + field->offset) >> 16;
4614 else if (field->filter_type == FILTER_PTR_STRING)
4615 size = strlen(key);
4616 else if (field->filter_type == FILTER_STATIC_STRING)
4617 size = field->size;
4618
4619 /* ensure NULL-termination */
4620 if (size > key_field->size - 1)
4621 size = key_field->size - 1;
4622 }
4623
4624 memcpy(compound_key + key_field->offset, key, size);
4625 }
4626
4627 static void
hist_trigger_actions(struct hist_trigger_data * hist_data,struct tracing_map_elt * elt,void * rec,struct ring_buffer_event * rbe,u64 * var_ref_vals)4628 hist_trigger_actions(struct hist_trigger_data *hist_data,
4629 struct tracing_map_elt *elt, void *rec,
4630 struct ring_buffer_event *rbe, u64 *var_ref_vals)
4631 {
4632 struct action_data *data;
4633 unsigned int i;
4634
4635 for (i = 0; i < hist_data->n_actions; i++) {
4636 data = hist_data->actions[i];
4637 data->fn(hist_data, elt, rec, rbe, data, var_ref_vals);
4638 }
4639 }
4640
event_hist_trigger(struct event_trigger_data * data,void * rec,struct ring_buffer_event * rbe)4641 static void event_hist_trigger(struct event_trigger_data *data, void *rec,
4642 struct ring_buffer_event *rbe)
4643 {
4644 struct hist_trigger_data *hist_data = data->private_data;
4645 bool use_compound_key = (hist_data->n_keys > 1);
4646 unsigned long entries[HIST_STACKTRACE_DEPTH];
4647 u64 var_ref_vals[TRACING_MAP_VARS_MAX];
4648 char compound_key[HIST_KEY_SIZE_MAX];
4649 struct tracing_map_elt *elt = NULL;
4650 struct stack_trace stacktrace;
4651 struct hist_field *key_field;
4652 u64 field_contents;
4653 void *key = NULL;
4654 unsigned int i;
4655
4656 memset(compound_key, 0, hist_data->key_size);
4657
4658 for_each_hist_key_field(i, hist_data) {
4659 key_field = hist_data->fields[i];
4660
4661 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4662 stacktrace.max_entries = HIST_STACKTRACE_DEPTH;
4663 stacktrace.entries = entries;
4664 stacktrace.nr_entries = 0;
4665 stacktrace.skip = HIST_STACKTRACE_SKIP;
4666
4667 memset(stacktrace.entries, 0, HIST_STACKTRACE_SIZE);
4668 save_stack_trace(&stacktrace);
4669
4670 key = entries;
4671 } else {
4672 field_contents = key_field->fn(key_field, elt, rbe, rec);
4673 if (key_field->flags & HIST_FIELD_FL_STRING) {
4674 key = (void *)(unsigned long)field_contents;
4675 use_compound_key = true;
4676 } else
4677 key = (void *)&field_contents;
4678 }
4679
4680 if (use_compound_key)
4681 add_to_key(compound_key, key, key_field, rec);
4682 }
4683
4684 if (use_compound_key)
4685 key = compound_key;
4686
4687 if (hist_data->n_var_refs &&
4688 !resolve_var_refs(hist_data, key, var_ref_vals, false))
4689 return;
4690
4691 elt = tracing_map_insert(hist_data->map, key);
4692 if (!elt)
4693 return;
4694
4695 hist_trigger_elt_update(hist_data, elt, rec, rbe, var_ref_vals);
4696
4697 if (resolve_var_refs(hist_data, key, var_ref_vals, true))
4698 hist_trigger_actions(hist_data, elt, rec, rbe, var_ref_vals);
4699 }
4700
hist_trigger_stacktrace_print(struct seq_file * m,unsigned long * stacktrace_entries,unsigned int max_entries)4701 static void hist_trigger_stacktrace_print(struct seq_file *m,
4702 unsigned long *stacktrace_entries,
4703 unsigned int max_entries)
4704 {
4705 char str[KSYM_SYMBOL_LEN];
4706 unsigned int spaces = 8;
4707 unsigned int i;
4708
4709 for (i = 0; i < max_entries; i++) {
4710 if (stacktrace_entries[i] == ULONG_MAX)
4711 return;
4712
4713 seq_printf(m, "%*c", 1 + spaces, ' ');
4714 sprint_symbol(str, stacktrace_entries[i]);
4715 seq_printf(m, "%s\n", str);
4716 }
4717 }
4718
4719 static void
hist_trigger_entry_print(struct seq_file * m,struct hist_trigger_data * hist_data,void * key,struct tracing_map_elt * elt)4720 hist_trigger_entry_print(struct seq_file *m,
4721 struct hist_trigger_data *hist_data, void *key,
4722 struct tracing_map_elt *elt)
4723 {
4724 struct hist_field *key_field;
4725 char str[KSYM_SYMBOL_LEN];
4726 bool multiline = false;
4727 const char *field_name;
4728 unsigned int i;
4729 u64 uval;
4730
4731 seq_puts(m, "{ ");
4732
4733 for_each_hist_key_field(i, hist_data) {
4734 key_field = hist_data->fields[i];
4735
4736 if (i > hist_data->n_vals)
4737 seq_puts(m, ", ");
4738
4739 field_name = hist_field_name(key_field, 0);
4740
4741 if (key_field->flags & HIST_FIELD_FL_HEX) {
4742 uval = *(u64 *)(key + key_field->offset);
4743 seq_printf(m, "%s: %llx", field_name, uval);
4744 } else if (key_field->flags & HIST_FIELD_FL_SYM) {
4745 uval = *(u64 *)(key + key_field->offset);
4746 sprint_symbol_no_offset(str, uval);
4747 seq_printf(m, "%s: [%llx] %-45s", field_name,
4748 uval, str);
4749 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
4750 uval = *(u64 *)(key + key_field->offset);
4751 sprint_symbol(str, uval);
4752 seq_printf(m, "%s: [%llx] %-55s", field_name,
4753 uval, str);
4754 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
4755 struct hist_elt_data *elt_data = elt->private_data;
4756 char *comm;
4757
4758 if (WARN_ON_ONCE(!elt_data))
4759 return;
4760
4761 comm = elt_data->comm;
4762
4763 uval = *(u64 *)(key + key_field->offset);
4764 seq_printf(m, "%s: %-16s[%10llu]", field_name,
4765 comm, uval);
4766 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
4767 const char *syscall_name;
4768
4769 uval = *(u64 *)(key + key_field->offset);
4770 syscall_name = get_syscall_name(uval);
4771 if (!syscall_name)
4772 syscall_name = "unknown_syscall";
4773
4774 seq_printf(m, "%s: %-30s[%3llu]", field_name,
4775 syscall_name, uval);
4776 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4777 seq_puts(m, "stacktrace:\n");
4778 hist_trigger_stacktrace_print(m,
4779 key + key_field->offset,
4780 HIST_STACKTRACE_DEPTH);
4781 multiline = true;
4782 } else if (key_field->flags & HIST_FIELD_FL_LOG2) {
4783 seq_printf(m, "%s: ~ 2^%-2llu", field_name,
4784 *(u64 *)(key + key_field->offset));
4785 } else if (key_field->flags & HIST_FIELD_FL_STRING) {
4786 seq_printf(m, "%s: %-50s", field_name,
4787 (char *)(key + key_field->offset));
4788 } else {
4789 uval = *(u64 *)(key + key_field->offset);
4790 seq_printf(m, "%s: %10llu", field_name, uval);
4791 }
4792 }
4793
4794 if (!multiline)
4795 seq_puts(m, " ");
4796
4797 seq_puts(m, "}");
4798
4799 seq_printf(m, " hitcount: %10llu",
4800 tracing_map_read_sum(elt, HITCOUNT_IDX));
4801
4802 for (i = 1; i < hist_data->n_vals; i++) {
4803 field_name = hist_field_name(hist_data->fields[i], 0);
4804
4805 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR ||
4806 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR)
4807 continue;
4808
4809 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) {
4810 seq_printf(m, " %s: %10llx", field_name,
4811 tracing_map_read_sum(elt, i));
4812 } else {
4813 seq_printf(m, " %s: %10llu", field_name,
4814 tracing_map_read_sum(elt, i));
4815 }
4816 }
4817
4818 print_actions(m, hist_data, elt);
4819
4820 seq_puts(m, "\n");
4821 }
4822
print_entries(struct seq_file * m,struct hist_trigger_data * hist_data)4823 static int print_entries(struct seq_file *m,
4824 struct hist_trigger_data *hist_data)
4825 {
4826 struct tracing_map_sort_entry **sort_entries = NULL;
4827 struct tracing_map *map = hist_data->map;
4828 int i, n_entries;
4829
4830 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys,
4831 hist_data->n_sort_keys,
4832 &sort_entries);
4833 if (n_entries < 0)
4834 return n_entries;
4835
4836 for (i = 0; i < n_entries; i++)
4837 hist_trigger_entry_print(m, hist_data,
4838 sort_entries[i]->key,
4839 sort_entries[i]->elt);
4840
4841 tracing_map_destroy_sort_entries(sort_entries, n_entries);
4842
4843 return n_entries;
4844 }
4845
hist_trigger_show(struct seq_file * m,struct event_trigger_data * data,int n)4846 static void hist_trigger_show(struct seq_file *m,
4847 struct event_trigger_data *data, int n)
4848 {
4849 struct hist_trigger_data *hist_data;
4850 int n_entries;
4851
4852 if (n > 0)
4853 seq_puts(m, "\n\n");
4854
4855 seq_puts(m, "# event histogram\n#\n# trigger info: ");
4856 data->ops->print(m, data->ops, data);
4857 seq_puts(m, "#\n\n");
4858
4859 hist_data = data->private_data;
4860 n_entries = print_entries(m, hist_data);
4861 if (n_entries < 0)
4862 n_entries = 0;
4863
4864 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
4865 (u64)atomic64_read(&hist_data->map->hits),
4866 n_entries, (u64)atomic64_read(&hist_data->map->drops));
4867 }
4868
hist_show(struct seq_file * m,void * v)4869 static int hist_show(struct seq_file *m, void *v)
4870 {
4871 struct event_trigger_data *data;
4872 struct trace_event_file *event_file;
4873 int n = 0, ret = 0;
4874
4875 mutex_lock(&event_mutex);
4876
4877 event_file = event_file_data(m->private);
4878 if (unlikely(!event_file)) {
4879 ret = -ENODEV;
4880 goto out_unlock;
4881 }
4882
4883 list_for_each_entry_rcu(data, &event_file->triggers, list) {
4884 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
4885 hist_trigger_show(m, data, n++);
4886 }
4887
4888 if (have_hist_err()) {
4889 seq_printf(m, "\nERROR: %s\n", hist_err_str);
4890 seq_printf(m, " Last command: %s\n", last_hist_cmd);
4891 }
4892
4893 out_unlock:
4894 mutex_unlock(&event_mutex);
4895
4896 return ret;
4897 }
4898
event_hist_open(struct inode * inode,struct file * file)4899 static int event_hist_open(struct inode *inode, struct file *file)
4900 {
4901 return single_open(file, hist_show, file);
4902 }
4903
4904 const struct file_operations event_hist_fops = {
4905 .open = event_hist_open,
4906 .read = seq_read,
4907 .llseek = seq_lseek,
4908 .release = single_release,
4909 };
4910
hist_field_print(struct seq_file * m,struct hist_field * hist_field)4911 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
4912 {
4913 const char *field_name = hist_field_name(hist_field, 0);
4914
4915 if (hist_field->var.name)
4916 seq_printf(m, "%s=", hist_field->var.name);
4917
4918 if (hist_field->flags & HIST_FIELD_FL_CPU)
4919 seq_puts(m, "cpu");
4920 else if (field_name) {
4921 if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
4922 hist_field->flags & HIST_FIELD_FL_ALIAS)
4923 seq_putc(m, '$');
4924 seq_printf(m, "%s", field_name);
4925 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP)
4926 seq_puts(m, "common_timestamp");
4927
4928 if (hist_field->flags) {
4929 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) &&
4930 !(hist_field->flags & HIST_FIELD_FL_EXPR)) {
4931 const char *flags = get_hist_field_flags(hist_field);
4932
4933 if (flags)
4934 seq_printf(m, ".%s", flags);
4935 }
4936 }
4937 }
4938
event_hist_trigger_print(struct seq_file * m,struct event_trigger_ops * ops,struct event_trigger_data * data)4939 static int event_hist_trigger_print(struct seq_file *m,
4940 struct event_trigger_ops *ops,
4941 struct event_trigger_data *data)
4942 {
4943 struct hist_trigger_data *hist_data = data->private_data;
4944 struct hist_field *field;
4945 bool have_var = false;
4946 unsigned int i;
4947
4948 seq_puts(m, "hist:");
4949
4950 if (data->name)
4951 seq_printf(m, "%s:", data->name);
4952
4953 seq_puts(m, "keys=");
4954
4955 for_each_hist_key_field(i, hist_data) {
4956 field = hist_data->fields[i];
4957
4958 if (i > hist_data->n_vals)
4959 seq_puts(m, ",");
4960
4961 if (field->flags & HIST_FIELD_FL_STACKTRACE)
4962 seq_puts(m, "stacktrace");
4963 else
4964 hist_field_print(m, field);
4965 }
4966
4967 seq_puts(m, ":vals=");
4968
4969 for_each_hist_val_field(i, hist_data) {
4970 field = hist_data->fields[i];
4971 if (field->flags & HIST_FIELD_FL_VAR) {
4972 have_var = true;
4973 continue;
4974 }
4975
4976 if (i == HITCOUNT_IDX)
4977 seq_puts(m, "hitcount");
4978 else {
4979 seq_puts(m, ",");
4980 hist_field_print(m, field);
4981 }
4982 }
4983
4984 if (have_var) {
4985 unsigned int n = 0;
4986
4987 seq_puts(m, ":");
4988
4989 for_each_hist_val_field(i, hist_data) {
4990 field = hist_data->fields[i];
4991
4992 if (field->flags & HIST_FIELD_FL_VAR) {
4993 if (n++)
4994 seq_puts(m, ",");
4995 hist_field_print(m, field);
4996 }
4997 }
4998 }
4999
5000 seq_puts(m, ":sort=");
5001
5002 for (i = 0; i < hist_data->n_sort_keys; i++) {
5003 struct tracing_map_sort_key *sort_key;
5004 unsigned int idx, first_key_idx;
5005
5006 /* skip VAR vals */
5007 first_key_idx = hist_data->n_vals - hist_data->n_vars;
5008
5009 sort_key = &hist_data->sort_keys[i];
5010 idx = sort_key->field_idx;
5011
5012 if (WARN_ON(idx >= HIST_FIELDS_MAX))
5013 return -EINVAL;
5014
5015 if (i > 0)
5016 seq_puts(m, ",");
5017
5018 if (idx == HITCOUNT_IDX)
5019 seq_puts(m, "hitcount");
5020 else {
5021 if (idx >= first_key_idx)
5022 idx += hist_data->n_vars;
5023 hist_field_print(m, hist_data->fields[idx]);
5024 }
5025
5026 if (sort_key->descending)
5027 seq_puts(m, ".descending");
5028 }
5029 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
5030 if (hist_data->enable_timestamps)
5031 seq_printf(m, ":clock=%s", hist_data->attrs->clock);
5032
5033 print_actions_spec(m, hist_data);
5034
5035 if (data->filter_str)
5036 seq_printf(m, " if %s", data->filter_str);
5037
5038 if (data->paused)
5039 seq_puts(m, " [paused]");
5040 else
5041 seq_puts(m, " [active]");
5042
5043 seq_putc(m, '\n');
5044
5045 return 0;
5046 }
5047
event_hist_trigger_init(struct event_trigger_ops * ops,struct event_trigger_data * data)5048 static int event_hist_trigger_init(struct event_trigger_ops *ops,
5049 struct event_trigger_data *data)
5050 {
5051 struct hist_trigger_data *hist_data = data->private_data;
5052
5053 if (!data->ref && hist_data->attrs->name)
5054 save_named_trigger(hist_data->attrs->name, data);
5055
5056 data->ref++;
5057
5058 return 0;
5059 }
5060
unregister_field_var_hists(struct hist_trigger_data * hist_data)5061 static void unregister_field_var_hists(struct hist_trigger_data *hist_data)
5062 {
5063 struct trace_event_file *file;
5064 unsigned int i;
5065 char *cmd;
5066 int ret;
5067
5068 for (i = 0; i < hist_data->n_field_var_hists; i++) {
5069 file = hist_data->field_var_hists[i]->hist_data->event_file;
5070 cmd = hist_data->field_var_hists[i]->cmd;
5071 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
5072 "!hist", "hist", cmd);
5073 }
5074 }
5075
event_hist_trigger_free(struct event_trigger_ops * ops,struct event_trigger_data * data)5076 static void event_hist_trigger_free(struct event_trigger_ops *ops,
5077 struct event_trigger_data *data)
5078 {
5079 struct hist_trigger_data *hist_data = data->private_data;
5080
5081 if (WARN_ON_ONCE(data->ref <= 0))
5082 return;
5083
5084 data->ref--;
5085 if (!data->ref) {
5086 if (data->name)
5087 del_named_trigger(data);
5088
5089 trigger_data_free(data);
5090
5091 remove_hist_vars(hist_data);
5092
5093 unregister_field_var_hists(hist_data);
5094
5095 destroy_hist_data(hist_data);
5096 }
5097 }
5098
5099 static struct event_trigger_ops event_hist_trigger_ops = {
5100 .func = event_hist_trigger,
5101 .print = event_hist_trigger_print,
5102 .init = event_hist_trigger_init,
5103 .free = event_hist_trigger_free,
5104 };
5105
event_hist_trigger_named_init(struct event_trigger_ops * ops,struct event_trigger_data * data)5106 static int event_hist_trigger_named_init(struct event_trigger_ops *ops,
5107 struct event_trigger_data *data)
5108 {
5109 data->ref++;
5110
5111 save_named_trigger(data->named_data->name, data);
5112
5113 event_hist_trigger_init(ops, data->named_data);
5114
5115 return 0;
5116 }
5117
event_hist_trigger_named_free(struct event_trigger_ops * ops,struct event_trigger_data * data)5118 static void event_hist_trigger_named_free(struct event_trigger_ops *ops,
5119 struct event_trigger_data *data)
5120 {
5121 if (WARN_ON_ONCE(data->ref <= 0))
5122 return;
5123
5124 event_hist_trigger_free(ops, data->named_data);
5125
5126 data->ref--;
5127 if (!data->ref) {
5128 del_named_trigger(data);
5129 trigger_data_free(data);
5130 }
5131 }
5132
5133 static struct event_trigger_ops event_hist_trigger_named_ops = {
5134 .func = event_hist_trigger,
5135 .print = event_hist_trigger_print,
5136 .init = event_hist_trigger_named_init,
5137 .free = event_hist_trigger_named_free,
5138 };
5139
event_hist_get_trigger_ops(char * cmd,char * param)5140 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
5141 char *param)
5142 {
5143 return &event_hist_trigger_ops;
5144 }
5145
hist_clear(struct event_trigger_data * data)5146 static void hist_clear(struct event_trigger_data *data)
5147 {
5148 struct hist_trigger_data *hist_data = data->private_data;
5149
5150 if (data->name)
5151 pause_named_trigger(data);
5152
5153 tracepoint_synchronize_unregister();
5154
5155 tracing_map_clear(hist_data->map);
5156
5157 if (data->name)
5158 unpause_named_trigger(data);
5159 }
5160
compatible_field(struct ftrace_event_field * field,struct ftrace_event_field * test_field)5161 static bool compatible_field(struct ftrace_event_field *field,
5162 struct ftrace_event_field *test_field)
5163 {
5164 if (field == test_field)
5165 return true;
5166 if (field == NULL || test_field == NULL)
5167 return false;
5168 if (strcmp(field->name, test_field->name) != 0)
5169 return false;
5170 if (strcmp(field->type, test_field->type) != 0)
5171 return false;
5172 if (field->size != test_field->size)
5173 return false;
5174 if (field->is_signed != test_field->is_signed)
5175 return false;
5176
5177 return true;
5178 }
5179
hist_trigger_match(struct event_trigger_data * data,struct event_trigger_data * data_test,struct event_trigger_data * named_data,bool ignore_filter)5180 static bool hist_trigger_match(struct event_trigger_data *data,
5181 struct event_trigger_data *data_test,
5182 struct event_trigger_data *named_data,
5183 bool ignore_filter)
5184 {
5185 struct tracing_map_sort_key *sort_key, *sort_key_test;
5186 struct hist_trigger_data *hist_data, *hist_data_test;
5187 struct hist_field *key_field, *key_field_test;
5188 unsigned int i;
5189
5190 if (named_data && (named_data != data_test) &&
5191 (named_data != data_test->named_data))
5192 return false;
5193
5194 if (!named_data && is_named_trigger(data_test))
5195 return false;
5196
5197 hist_data = data->private_data;
5198 hist_data_test = data_test->private_data;
5199
5200 if (hist_data->n_vals != hist_data_test->n_vals ||
5201 hist_data->n_fields != hist_data_test->n_fields ||
5202 hist_data->n_sort_keys != hist_data_test->n_sort_keys)
5203 return false;
5204
5205 if (!ignore_filter) {
5206 if ((data->filter_str && !data_test->filter_str) ||
5207 (!data->filter_str && data_test->filter_str))
5208 return false;
5209 }
5210
5211 for_each_hist_field(i, hist_data) {
5212 key_field = hist_data->fields[i];
5213 key_field_test = hist_data_test->fields[i];
5214
5215 if (key_field->flags != key_field_test->flags)
5216 return false;
5217 if (!compatible_field(key_field->field, key_field_test->field))
5218 return false;
5219 if (key_field->offset != key_field_test->offset)
5220 return false;
5221 if (key_field->size != key_field_test->size)
5222 return false;
5223 if (key_field->is_signed != key_field_test->is_signed)
5224 return false;
5225 if (!!key_field->var.name != !!key_field_test->var.name)
5226 return false;
5227 if (key_field->var.name &&
5228 strcmp(key_field->var.name, key_field_test->var.name) != 0)
5229 return false;
5230 }
5231
5232 for (i = 0; i < hist_data->n_sort_keys; i++) {
5233 sort_key = &hist_data->sort_keys[i];
5234 sort_key_test = &hist_data_test->sort_keys[i];
5235
5236 if (sort_key->field_idx != sort_key_test->field_idx ||
5237 sort_key->descending != sort_key_test->descending)
5238 return false;
5239 }
5240
5241 if (!ignore_filter && data->filter_str &&
5242 (strcmp(data->filter_str, data_test->filter_str) != 0))
5243 return false;
5244
5245 if (!actions_match(hist_data, hist_data_test))
5246 return false;
5247
5248 return true;
5249 }
5250
hist_register_trigger(char * glob,struct event_trigger_ops * ops,struct event_trigger_data * data,struct trace_event_file * file)5251 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
5252 struct event_trigger_data *data,
5253 struct trace_event_file *file)
5254 {
5255 struct hist_trigger_data *hist_data = data->private_data;
5256 struct event_trigger_data *test, *named_data = NULL;
5257 int ret = 0;
5258
5259 if (hist_data->attrs->name) {
5260 named_data = find_named_trigger(hist_data->attrs->name);
5261 if (named_data) {
5262 if (!hist_trigger_match(data, named_data, named_data,
5263 true)) {
5264 hist_err("Named hist trigger doesn't match existing named trigger (includes variables): ", hist_data->attrs->name);
5265 ret = -EINVAL;
5266 goto out;
5267 }
5268 }
5269 }
5270
5271 if (hist_data->attrs->name && !named_data)
5272 goto new;
5273
5274 list_for_each_entry_rcu(test, &file->triggers, list) {
5275 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5276 if (!hist_trigger_match(data, test, named_data, false))
5277 continue;
5278 if (hist_data->attrs->pause)
5279 test->paused = true;
5280 else if (hist_data->attrs->cont)
5281 test->paused = false;
5282 else if (hist_data->attrs->clear)
5283 hist_clear(test);
5284 else {
5285 hist_err("Hist trigger already exists", NULL);
5286 ret = -EEXIST;
5287 }
5288 goto out;
5289 }
5290 }
5291 new:
5292 if (hist_data->attrs->cont || hist_data->attrs->clear) {
5293 hist_err("Can't clear or continue a nonexistent hist trigger", NULL);
5294 ret = -ENOENT;
5295 goto out;
5296 }
5297
5298 if (hist_data->attrs->pause)
5299 data->paused = true;
5300
5301 if (named_data) {
5302 data->private_data = named_data->private_data;
5303 set_named_trigger_data(data, named_data);
5304 data->ops = &event_hist_trigger_named_ops;
5305 }
5306
5307 if (data->ops->init) {
5308 ret = data->ops->init(data->ops, data);
5309 if (ret < 0)
5310 goto out;
5311 }
5312
5313 if (hist_data->enable_timestamps) {
5314 char *clock = hist_data->attrs->clock;
5315
5316 ret = tracing_set_clock(file->tr, hist_data->attrs->clock);
5317 if (ret) {
5318 hist_err("Couldn't set trace_clock: ", clock);
5319 goto out;
5320 }
5321
5322 tracing_set_time_stamp_abs(file->tr, true);
5323 }
5324
5325 if (named_data)
5326 destroy_hist_data(hist_data);
5327
5328 ret++;
5329 out:
5330 return ret;
5331 }
5332
hist_trigger_enable(struct event_trigger_data * data,struct trace_event_file * file)5333 static int hist_trigger_enable(struct event_trigger_data *data,
5334 struct trace_event_file *file)
5335 {
5336 int ret = 0;
5337
5338 list_add_tail_rcu(&data->list, &file->triggers);
5339
5340 update_cond_flag(file);
5341
5342 if (trace_event_trigger_enable_disable(file, 1) < 0) {
5343 list_del_rcu(&data->list);
5344 update_cond_flag(file);
5345 ret--;
5346 }
5347
5348 return ret;
5349 }
5350
have_hist_trigger_match(struct event_trigger_data * data,struct trace_event_file * file)5351 static bool have_hist_trigger_match(struct event_trigger_data *data,
5352 struct trace_event_file *file)
5353 {
5354 struct hist_trigger_data *hist_data = data->private_data;
5355 struct event_trigger_data *test, *named_data = NULL;
5356 bool match = false;
5357
5358 if (hist_data->attrs->name)
5359 named_data = find_named_trigger(hist_data->attrs->name);
5360
5361 list_for_each_entry_rcu(test, &file->triggers, list) {
5362 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5363 if (hist_trigger_match(data, test, named_data, false)) {
5364 match = true;
5365 break;
5366 }
5367 }
5368 }
5369
5370 return match;
5371 }
5372
hist_trigger_check_refs(struct event_trigger_data * data,struct trace_event_file * file)5373 static bool hist_trigger_check_refs(struct event_trigger_data *data,
5374 struct trace_event_file *file)
5375 {
5376 struct hist_trigger_data *hist_data = data->private_data;
5377 struct event_trigger_data *test, *named_data = NULL;
5378
5379 if (hist_data->attrs->name)
5380 named_data = find_named_trigger(hist_data->attrs->name);
5381
5382 list_for_each_entry_rcu(test, &file->triggers, list) {
5383 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5384 if (!hist_trigger_match(data, test, named_data, false))
5385 continue;
5386 hist_data = test->private_data;
5387 if (check_var_refs(hist_data))
5388 return true;
5389 break;
5390 }
5391 }
5392
5393 return false;
5394 }
5395
hist_unregister_trigger(char * glob,struct event_trigger_ops * ops,struct event_trigger_data * data,struct trace_event_file * file)5396 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops,
5397 struct event_trigger_data *data,
5398 struct trace_event_file *file)
5399 {
5400 struct hist_trigger_data *hist_data = data->private_data;
5401 struct event_trigger_data *test, *named_data = NULL;
5402 bool unregistered = false;
5403
5404 if (hist_data->attrs->name)
5405 named_data = find_named_trigger(hist_data->attrs->name);
5406
5407 list_for_each_entry_rcu(test, &file->triggers, list) {
5408 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5409 if (!hist_trigger_match(data, test, named_data, false))
5410 continue;
5411 unregistered = true;
5412 list_del_rcu(&test->list);
5413 trace_event_trigger_enable_disable(file, 0);
5414 update_cond_flag(file);
5415 break;
5416 }
5417 }
5418
5419 if (unregistered && test->ops->free)
5420 test->ops->free(test->ops, test);
5421
5422 if (hist_data->enable_timestamps) {
5423 if (!hist_data->remove || unregistered)
5424 tracing_set_time_stamp_abs(file->tr, false);
5425 }
5426 }
5427
hist_file_check_refs(struct trace_event_file * file)5428 static bool hist_file_check_refs(struct trace_event_file *file)
5429 {
5430 struct hist_trigger_data *hist_data;
5431 struct event_trigger_data *test;
5432
5433 list_for_each_entry_rcu(test, &file->triggers, list) {
5434 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5435 hist_data = test->private_data;
5436 if (check_var_refs(hist_data))
5437 return true;
5438 }
5439 }
5440
5441 return false;
5442 }
5443
hist_unreg_all(struct trace_event_file * file)5444 static void hist_unreg_all(struct trace_event_file *file)
5445 {
5446 struct event_trigger_data *test, *n;
5447 struct hist_trigger_data *hist_data;
5448 struct synth_event *se;
5449 const char *se_name;
5450
5451 if (hist_file_check_refs(file))
5452 return;
5453
5454 list_for_each_entry_safe(test, n, &file->triggers, list) {
5455 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5456 hist_data = test->private_data;
5457 list_del_rcu(&test->list);
5458 trace_event_trigger_enable_disable(file, 0);
5459
5460 mutex_lock(&synth_event_mutex);
5461 se_name = trace_event_name(file->event_call);
5462 se = find_synth_event(se_name);
5463 if (se)
5464 se->ref--;
5465 mutex_unlock(&synth_event_mutex);
5466
5467 update_cond_flag(file);
5468 if (hist_data->enable_timestamps)
5469 tracing_set_time_stamp_abs(file->tr, false);
5470 if (test->ops->free)
5471 test->ops->free(test->ops, test);
5472 }
5473 }
5474 }
5475
event_hist_trigger_func(struct event_command * cmd_ops,struct trace_event_file * file,char * glob,char * cmd,char * param)5476 static int event_hist_trigger_func(struct event_command *cmd_ops,
5477 struct trace_event_file *file,
5478 char *glob, char *cmd, char *param)
5479 {
5480 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
5481 struct event_trigger_data *trigger_data;
5482 struct hist_trigger_attrs *attrs;
5483 struct event_trigger_ops *trigger_ops;
5484 struct hist_trigger_data *hist_data;
5485 struct synth_event *se;
5486 const char *se_name;
5487 bool remove = false;
5488 char *trigger, *p;
5489 int ret = 0;
5490
5491 if (glob && strlen(glob)) {
5492 last_cmd_set(param);
5493 hist_err_clear();
5494 }
5495
5496 if (!param)
5497 return -EINVAL;
5498
5499 if (glob[0] == '!')
5500 remove = true;
5501
5502 /*
5503 * separate the trigger from the filter (k:v [if filter])
5504 * allowing for whitespace in the trigger
5505 */
5506 p = trigger = param;
5507 do {
5508 p = strstr(p, "if");
5509 if (!p)
5510 break;
5511 if (p == param)
5512 return -EINVAL;
5513 if (*(p - 1) != ' ' && *(p - 1) != '\t') {
5514 p++;
5515 continue;
5516 }
5517 if (p >= param + strlen(param) - strlen("if") - 1)
5518 return -EINVAL;
5519 if (*(p + strlen("if")) != ' ' && *(p + strlen("if")) != '\t') {
5520 p++;
5521 continue;
5522 }
5523 break;
5524 } while (p);
5525
5526 if (!p)
5527 param = NULL;
5528 else {
5529 *(p - 1) = '\0';
5530 param = strstrip(p);
5531 trigger = strstrip(trigger);
5532 }
5533
5534 attrs = parse_hist_trigger_attrs(trigger);
5535 if (IS_ERR(attrs))
5536 return PTR_ERR(attrs);
5537
5538 if (attrs->map_bits)
5539 hist_trigger_bits = attrs->map_bits;
5540
5541 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove);
5542 if (IS_ERR(hist_data)) {
5543 destroy_hist_trigger_attrs(attrs);
5544 return PTR_ERR(hist_data);
5545 }
5546
5547 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
5548
5549 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
5550 if (!trigger_data) {
5551 ret = -ENOMEM;
5552 goto out_free;
5553 }
5554
5555 trigger_data->count = -1;
5556 trigger_data->ops = trigger_ops;
5557 trigger_data->cmd_ops = cmd_ops;
5558
5559 INIT_LIST_HEAD(&trigger_data->list);
5560 RCU_INIT_POINTER(trigger_data->filter, NULL);
5561
5562 trigger_data->private_data = hist_data;
5563
5564 /* if param is non-empty, it's supposed to be a filter */
5565 if (param && cmd_ops->set_filter) {
5566 ret = cmd_ops->set_filter(param, trigger_data, file);
5567 if (ret < 0)
5568 goto out_free;
5569 }
5570
5571 if (remove) {
5572 if (!have_hist_trigger_match(trigger_data, file))
5573 goto out_free;
5574
5575 if (hist_trigger_check_refs(trigger_data, file)) {
5576 ret = -EBUSY;
5577 goto out_free;
5578 }
5579
5580 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5581
5582 mutex_lock(&synth_event_mutex);
5583 se_name = trace_event_name(file->event_call);
5584 se = find_synth_event(se_name);
5585 if (se)
5586 se->ref--;
5587 mutex_unlock(&synth_event_mutex);
5588
5589 ret = 0;
5590 goto out_free;
5591 }
5592
5593 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
5594 /*
5595 * The above returns on success the # of triggers registered,
5596 * but if it didn't register any it returns zero. Consider no
5597 * triggers registered a failure too.
5598 */
5599 if (!ret) {
5600 if (!(attrs->pause || attrs->cont || attrs->clear))
5601 ret = -ENOENT;
5602 goto out_free;
5603 } else if (ret < 0)
5604 goto out_free;
5605
5606 if (get_named_trigger_data(trigger_data))
5607 goto enable;
5608
5609 if (has_hist_vars(hist_data))
5610 save_hist_vars(hist_data);
5611
5612 ret = create_actions(hist_data, file);
5613 if (ret)
5614 goto out_unreg;
5615
5616 ret = tracing_map_init(hist_data->map);
5617 if (ret)
5618 goto out_unreg;
5619 enable:
5620 ret = hist_trigger_enable(trigger_data, file);
5621 if (ret)
5622 goto out_unreg;
5623
5624 mutex_lock(&synth_event_mutex);
5625 se_name = trace_event_name(file->event_call);
5626 se = find_synth_event(se_name);
5627 if (se)
5628 se->ref++;
5629 mutex_unlock(&synth_event_mutex);
5630
5631 /* Just return zero, not the number of registered triggers */
5632 ret = 0;
5633 out:
5634 if (ret == 0)
5635 hist_err_clear();
5636
5637 return ret;
5638 out_unreg:
5639 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5640 out_free:
5641 if (cmd_ops->set_filter)
5642 cmd_ops->set_filter(NULL, trigger_data, NULL);
5643
5644 remove_hist_vars(hist_data);
5645
5646 kfree(trigger_data);
5647
5648 destroy_hist_data(hist_data);
5649 goto out;
5650 }
5651
5652 static struct event_command trigger_hist_cmd = {
5653 .name = "hist",
5654 .trigger_type = ETT_EVENT_HIST,
5655 .flags = EVENT_CMD_FL_NEEDS_REC,
5656 .func = event_hist_trigger_func,
5657 .reg = hist_register_trigger,
5658 .unreg = hist_unregister_trigger,
5659 .unreg_all = hist_unreg_all,
5660 .get_trigger_ops = event_hist_get_trigger_ops,
5661 .set_filter = set_trigger_filter,
5662 };
5663
register_trigger_hist_cmd(void)5664 __init int register_trigger_hist_cmd(void)
5665 {
5666 int ret;
5667
5668 ret = register_event_command(&trigger_hist_cmd);
5669 WARN_ON(ret < 0);
5670
5671 return ret;
5672 }
5673
5674 static void
hist_enable_trigger(struct event_trigger_data * data,void * rec,struct ring_buffer_event * event)5675 hist_enable_trigger(struct event_trigger_data *data, void *rec,
5676 struct ring_buffer_event *event)
5677 {
5678 struct enable_trigger_data *enable_data = data->private_data;
5679 struct event_trigger_data *test;
5680
5681 list_for_each_entry_rcu(test, &enable_data->file->triggers, list) {
5682 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5683 if (enable_data->enable)
5684 test->paused = false;
5685 else
5686 test->paused = true;
5687 }
5688 }
5689 }
5690
5691 static void
hist_enable_count_trigger(struct event_trigger_data * data,void * rec,struct ring_buffer_event * event)5692 hist_enable_count_trigger(struct event_trigger_data *data, void *rec,
5693 struct ring_buffer_event *event)
5694 {
5695 if (!data->count)
5696 return;
5697
5698 if (data->count != -1)
5699 (data->count)--;
5700
5701 hist_enable_trigger(data, rec, event);
5702 }
5703
5704 static struct event_trigger_ops hist_enable_trigger_ops = {
5705 .func = hist_enable_trigger,
5706 .print = event_enable_trigger_print,
5707 .init = event_trigger_init,
5708 .free = event_enable_trigger_free,
5709 };
5710
5711 static struct event_trigger_ops hist_enable_count_trigger_ops = {
5712 .func = hist_enable_count_trigger,
5713 .print = event_enable_trigger_print,
5714 .init = event_trigger_init,
5715 .free = event_enable_trigger_free,
5716 };
5717
5718 static struct event_trigger_ops hist_disable_trigger_ops = {
5719 .func = hist_enable_trigger,
5720 .print = event_enable_trigger_print,
5721 .init = event_trigger_init,
5722 .free = event_enable_trigger_free,
5723 };
5724
5725 static struct event_trigger_ops hist_disable_count_trigger_ops = {
5726 .func = hist_enable_count_trigger,
5727 .print = event_enable_trigger_print,
5728 .init = event_trigger_init,
5729 .free = event_enable_trigger_free,
5730 };
5731
5732 static struct event_trigger_ops *
hist_enable_get_trigger_ops(char * cmd,char * param)5733 hist_enable_get_trigger_ops(char *cmd, char *param)
5734 {
5735 struct event_trigger_ops *ops;
5736 bool enable;
5737
5738 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0);
5739
5740 if (enable)
5741 ops = param ? &hist_enable_count_trigger_ops :
5742 &hist_enable_trigger_ops;
5743 else
5744 ops = param ? &hist_disable_count_trigger_ops :
5745 &hist_disable_trigger_ops;
5746
5747 return ops;
5748 }
5749
hist_enable_unreg_all(struct trace_event_file * file)5750 static void hist_enable_unreg_all(struct trace_event_file *file)
5751 {
5752 struct event_trigger_data *test, *n;
5753
5754 list_for_each_entry_safe(test, n, &file->triggers, list) {
5755 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) {
5756 list_del_rcu(&test->list);
5757 update_cond_flag(file);
5758 trace_event_trigger_enable_disable(file, 0);
5759 if (test->ops->free)
5760 test->ops->free(test->ops, test);
5761 }
5762 }
5763 }
5764
5765 static struct event_command trigger_hist_enable_cmd = {
5766 .name = ENABLE_HIST_STR,
5767 .trigger_type = ETT_HIST_ENABLE,
5768 .func = event_enable_trigger_func,
5769 .reg = event_enable_register_trigger,
5770 .unreg = event_enable_unregister_trigger,
5771 .unreg_all = hist_enable_unreg_all,
5772 .get_trigger_ops = hist_enable_get_trigger_ops,
5773 .set_filter = set_trigger_filter,
5774 };
5775
5776 static struct event_command trigger_hist_disable_cmd = {
5777 .name = DISABLE_HIST_STR,
5778 .trigger_type = ETT_HIST_ENABLE,
5779 .func = event_enable_trigger_func,
5780 .reg = event_enable_register_trigger,
5781 .unreg = event_enable_unregister_trigger,
5782 .unreg_all = hist_enable_unreg_all,
5783 .get_trigger_ops = hist_enable_get_trigger_ops,
5784 .set_filter = set_trigger_filter,
5785 };
5786
unregister_trigger_hist_enable_disable_cmds(void)5787 static __init void unregister_trigger_hist_enable_disable_cmds(void)
5788 {
5789 unregister_event_command(&trigger_hist_enable_cmd);
5790 unregister_event_command(&trigger_hist_disable_cmd);
5791 }
5792
register_trigger_hist_enable_disable_cmds(void)5793 __init int register_trigger_hist_enable_disable_cmds(void)
5794 {
5795 int ret;
5796
5797 ret = register_event_command(&trigger_hist_enable_cmd);
5798 if (WARN_ON(ret < 0))
5799 return ret;
5800 ret = register_event_command(&trigger_hist_disable_cmd);
5801 if (WARN_ON(ret < 0))
5802 unregister_trigger_hist_enable_disable_cmds();
5803
5804 return ret;
5805 }
5806
trace_events_hist_init(void)5807 static __init int trace_events_hist_init(void)
5808 {
5809 struct dentry *entry = NULL;
5810 struct dentry *d_tracer;
5811 int err = 0;
5812
5813 d_tracer = tracing_init_dentry();
5814 if (IS_ERR(d_tracer)) {
5815 err = PTR_ERR(d_tracer);
5816 goto err;
5817 }
5818
5819 entry = tracefs_create_file("synthetic_events", 0644, d_tracer,
5820 NULL, &synth_events_fops);
5821 if (!entry) {
5822 err = -ENODEV;
5823 goto err;
5824 }
5825
5826 return err;
5827 err:
5828 pr_warn("Could not create tracefs 'synthetic_events' entry\n");
5829
5830 return err;
5831 }
5832
5833 fs_initcall(trace_events_hist_init);
5834
