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mm/hmm.c: remove superfluous RCU protection around radix tree lookup
[linux/fpc-iii.git] / kernel / trace / trace_events_hist.c
blob0d7b3ffbecc2a03a7604509e2f19cdd3df5e4973
1 /*
2 * trace_events_hist - trace event hist triggers
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com>
15 */
16
17 #include <linux/module.h>
18 #include <linux/kallsyms.h>
19 #include <linux/mutex.h>
20 #include <linux/slab.h>
21 #include <linux/stacktrace.h>
22 #include <linux/rculist.h>
23 #include <linux/tracefs.h>
24
25 #include "tracing_map.h"
26 #include "trace.h"
27
28 #define SYNTH_SYSTEM "synthetic"
29 #define SYNTH_FIELDS_MAX 16
30
31 #define STR_VAR_LEN_MAX 32 /* must be multiple of sizeof(u64) */
32
33 struct hist_field;
34
35 typedef u64 (*hist_field_fn_t) (struct hist_field *field,
36 struct tracing_map_elt *elt,
37 struct ring_buffer_event *rbe,
38 void *event);
39
40 #define HIST_FIELD_OPERANDS_MAX 2
41 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX)
42 #define HIST_ACTIONS_MAX 8
43
44 enum field_op_id {
45 FIELD_OP_NONE,
46 FIELD_OP_PLUS,
47 FIELD_OP_MINUS,
48 FIELD_OP_UNARY_MINUS,
49 };
50
51 struct hist_var {
52 char *name;
53 struct hist_trigger_data *hist_data;
54 unsigned int idx;
55 };
56
57 struct hist_field {
58 struct ftrace_event_field *field;
59 unsigned long flags;
60 hist_field_fn_t fn;
61 unsigned int size;
62 unsigned int offset;
63 unsigned int is_signed;
64 const char *type;
65 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX];
66 struct hist_trigger_data *hist_data;
67 struct hist_var var;
68 enum field_op_id operator;
69 char *system;
70 char *event_name;
71 char *name;
72 unsigned int var_idx;
73 unsigned int var_ref_idx;
74 bool read_once;
75 };
76
77 static u64 hist_field_none(struct hist_field *field,
78 struct tracing_map_elt *elt,
79 struct ring_buffer_event *rbe,
80 void *event)
81 {
82 return 0;
83 }
84
85 static u64 hist_field_counter(struct hist_field *field,
86 struct tracing_map_elt *elt,
87 struct ring_buffer_event *rbe,
88 void *event)
89 {
90 return 1;
91 }
92
93 static u64 hist_field_string(struct hist_field *hist_field,
94 struct tracing_map_elt *elt,
95 struct ring_buffer_event *rbe,
96 void *event)
97 {
98 char *addr = (char *)(event + hist_field->field->offset);
99
100 return (u64)(unsigned long)addr;
101 }
102
103 static u64 hist_field_dynstring(struct hist_field *hist_field,
104 struct tracing_map_elt *elt,
105 struct ring_buffer_event *rbe,
106 void *event)
107 {
108 u32 str_item = *(u32 *)(event + hist_field->field->offset);
109 int str_loc = str_item & 0xffff;
110 char *addr = (char *)(event + str_loc);
111
112 return (u64)(unsigned long)addr;
113 }
114
115 static u64 hist_field_pstring(struct hist_field *hist_field,
116 struct tracing_map_elt *elt,
117 struct ring_buffer_event *rbe,
118 void *event)
119 {
120 char **addr = (char **)(event + hist_field->field->offset);
121
122 return (u64)(unsigned long)*addr;
123 }
124
125 static u64 hist_field_log2(struct hist_field *hist_field,
126 struct tracing_map_elt *elt,
127 struct ring_buffer_event *rbe,
128 void *event)
129 {
130 struct hist_field *operand = hist_field->operands[0];
131
132 u64 val = operand->fn(operand, elt, rbe, event);
133
134 return (u64) ilog2(roundup_pow_of_two(val));
135 }
136
137 static u64 hist_field_plus(struct hist_field *hist_field,
138 struct tracing_map_elt *elt,
139 struct ring_buffer_event *rbe,
140 void *event)
141 {
142 struct hist_field *operand1 = hist_field->operands[0];
143 struct hist_field *operand2 = hist_field->operands[1];
144
145 u64 val1 = operand1->fn(operand1, elt, rbe, event);
146 u64 val2 = operand2->fn(operand2, elt, rbe, event);
147
148 return val1 + val2;
149 }
150
151 static u64 hist_field_minus(struct hist_field *hist_field,
152 struct tracing_map_elt *elt,
153 struct ring_buffer_event *rbe,
154 void *event)
155 {
156 struct hist_field *operand1 = hist_field->operands[0];
157 struct hist_field *operand2 = hist_field->operands[1];
158
159 u64 val1 = operand1->fn(operand1, elt, rbe, event);
160 u64 val2 = operand2->fn(operand2, elt, rbe, event);
161
162 return val1 - val2;
163 }
164
165 static u64 hist_field_unary_minus(struct hist_field *hist_field,
166 struct tracing_map_elt *elt,
167 struct ring_buffer_event *rbe,
168 void *event)
169 {
170 struct hist_field *operand = hist_field->operands[0];
171
172 s64 sval = (s64)operand->fn(operand, elt, rbe, event);
173 u64 val = (u64)-sval;
174
175 return val;
176 }
177
178 #define DEFINE_HIST_FIELD_FN(type) \
179 static u64 hist_field_##type(struct hist_field *hist_field, \
180 struct tracing_map_elt *elt, \
181 struct ring_buffer_event *rbe, \
182 void *event) \
183 { \
184 type *addr = (type *)(event + hist_field->field->offset); \
185 \
186 return (u64)(unsigned long)*addr; \
187 }
188
189 DEFINE_HIST_FIELD_FN(s64);
190 DEFINE_HIST_FIELD_FN(u64);
191 DEFINE_HIST_FIELD_FN(s32);
192 DEFINE_HIST_FIELD_FN(u32);
193 DEFINE_HIST_FIELD_FN(s16);
194 DEFINE_HIST_FIELD_FN(u16);
195 DEFINE_HIST_FIELD_FN(s8);
196 DEFINE_HIST_FIELD_FN(u8);
197
198 #define for_each_hist_field(i, hist_data) \
199 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++)
200
201 #define for_each_hist_val_field(i, hist_data) \
202 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++)
203
204 #define for_each_hist_key_field(i, hist_data) \
205 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++)
206
207 #define HIST_STACKTRACE_DEPTH 16
208 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
209 #define HIST_STACKTRACE_SKIP 5
210
211 #define HITCOUNT_IDX 0
212 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE)
213
214 enum hist_field_flags {
215 HIST_FIELD_FL_HITCOUNT = 1 << 0,
216 HIST_FIELD_FL_KEY = 1 << 1,
217 HIST_FIELD_FL_STRING = 1 << 2,
218 HIST_FIELD_FL_HEX = 1 << 3,
219 HIST_FIELD_FL_SYM = 1 << 4,
220 HIST_FIELD_FL_SYM_OFFSET = 1 << 5,
221 HIST_FIELD_FL_EXECNAME = 1 << 6,
222 HIST_FIELD_FL_SYSCALL = 1 << 7,
223 HIST_FIELD_FL_STACKTRACE = 1 << 8,
224 HIST_FIELD_FL_LOG2 = 1 << 9,
225 HIST_FIELD_FL_TIMESTAMP = 1 << 10,
226 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11,
227 HIST_FIELD_FL_VAR = 1 << 12,
228 HIST_FIELD_FL_EXPR = 1 << 13,
229 HIST_FIELD_FL_VAR_REF = 1 << 14,
230 HIST_FIELD_FL_CPU = 1 << 15,
231 HIST_FIELD_FL_ALIAS = 1 << 16,
232 };
233
234 struct var_defs {
235 unsigned int n_vars;
236 char *name[TRACING_MAP_VARS_MAX];
237 char *expr[TRACING_MAP_VARS_MAX];
238 };
239
240 struct hist_trigger_attrs {
241 char *keys_str;
242 char *vals_str;
243 char *sort_key_str;
244 char *name;
245 char *clock;
246 bool pause;
247 bool cont;
248 bool clear;
249 bool ts_in_usecs;
250 unsigned int map_bits;
251
252 char *assignment_str[TRACING_MAP_VARS_MAX];
253 unsigned int n_assignments;
254
255 char *action_str[HIST_ACTIONS_MAX];
256 unsigned int n_actions;
257
258 struct var_defs var_defs;
259 };
260
261 struct field_var {
262 struct hist_field *var;
263 struct hist_field *val;
264 };
265
266 struct field_var_hist {
267 struct hist_trigger_data *hist_data;
268 char *cmd;
269 };
270
271 struct hist_trigger_data {
272 struct hist_field *fields[HIST_FIELDS_MAX];
273 unsigned int n_vals;
274 unsigned int n_keys;
275 unsigned int n_fields;
276 unsigned int n_vars;
277 unsigned int key_size;
278 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX];
279 unsigned int n_sort_keys;
280 struct trace_event_file *event_file;
281 struct hist_trigger_attrs *attrs;
282 struct tracing_map *map;
283 bool enable_timestamps;
284 bool remove;
285 struct hist_field *var_refs[TRACING_MAP_VARS_MAX];
286 unsigned int n_var_refs;
287
288 struct action_data *actions[HIST_ACTIONS_MAX];
289 unsigned int n_actions;
290
291 struct hist_field *synth_var_refs[SYNTH_FIELDS_MAX];
292 unsigned int n_synth_var_refs;
293 struct field_var *field_vars[SYNTH_FIELDS_MAX];
294 unsigned int n_field_vars;
295 unsigned int n_field_var_str;
296 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX];
297 unsigned int n_field_var_hists;
298
299 struct field_var *max_vars[SYNTH_FIELDS_MAX];
300 unsigned int n_max_vars;
301 unsigned int n_max_var_str;
302 };
303
304 struct synth_field {
305 char *type;
306 char *name;
307 size_t size;
308 bool is_signed;
309 bool is_string;
310 };
311
312 struct synth_event {
313 struct list_head list;
314 int ref;
315 char *name;
316 struct synth_field **fields;
317 unsigned int n_fields;
318 unsigned int n_u64;
319 struct trace_event_class class;
320 struct trace_event_call call;
321 struct tracepoint *tp;
322 };
323
324 struct action_data;
325
326 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data,
327 struct tracing_map_elt *elt, void *rec,
328 struct ring_buffer_event *rbe,
329 struct action_data *data, u64 *var_ref_vals);
330
331 struct action_data {
332 action_fn_t fn;
333 unsigned int n_params;
334 char *params[SYNTH_FIELDS_MAX];
335
336 union {
337 struct {
338 unsigned int var_ref_idx;
339 char *match_event;
340 char *match_event_system;
341 char *synth_event_name;
342 struct synth_event *synth_event;
343 } onmatch;
344
345 struct {
346 char *var_str;
347 char *fn_name;
348 unsigned int max_var_ref_idx;
349 struct hist_field *max_var;
350 struct hist_field *var;
351 } onmax;
352 };
353 };
354
355
356 static char last_hist_cmd[MAX_FILTER_STR_VAL];
357 static char hist_err_str[MAX_FILTER_STR_VAL];
358
359 static void last_cmd_set(char *str)
360 {
361 if (!str)
362 return;
363
364 strncpy(last_hist_cmd, str, MAX_FILTER_STR_VAL - 1);
365 }
366
367 static void hist_err(char *str, char *var)
368 {
369 int maxlen = MAX_FILTER_STR_VAL - 1;
370
371 if (!str)
372 return;
373
374 if (strlen(hist_err_str))
375 return;
376
377 if (!var)
378 var = "";
379
380 if (strlen(hist_err_str) + strlen(str) + strlen(var) > maxlen)
381 return;
382
383 strcat(hist_err_str, str);
384 strcat(hist_err_str, var);
385 }
386
387 static void hist_err_event(char *str, char *system, char *event, char *var)
388 {
389 char err[MAX_FILTER_STR_VAL];
390
391 if (system && var)
392 snprintf(err, MAX_FILTER_STR_VAL, "%s.%s.%s", system, event, var);
393 else if (system)
394 snprintf(err, MAX_FILTER_STR_VAL, "%s.%s", system, event);
395 else
396 strncpy(err, var, MAX_FILTER_STR_VAL);
397
398 hist_err(str, err);
399 }
400
401 static void hist_err_clear(void)
402 {
403 hist_err_str[0] = '\0';
404 }
405
406 static bool have_hist_err(void)
407 {
408 if (strlen(hist_err_str))
409 return true;
410
411 return false;
412 }
413
414 static LIST_HEAD(synth_event_list);
415 static DEFINE_MUTEX(synth_event_mutex);
416
417 struct synth_trace_event {
418 struct trace_entry ent;
419 u64 fields[];
420 };
421
422 static int synth_event_define_fields(struct trace_event_call *call)
423 {
424 struct synth_trace_event trace;
425 int offset = offsetof(typeof(trace), fields);
426 struct synth_event *event = call->data;
427 unsigned int i, size, n_u64;
428 char *name, *type;
429 bool is_signed;
430 int ret = 0;
431
432 for (i = 0, n_u64 = 0; i < event->n_fields; i++) {
433 size = event->fields[i]->size;
434 is_signed = event->fields[i]->is_signed;
435 type = event->fields[i]->type;
436 name = event->fields[i]->name;
437 ret = trace_define_field(call, type, name, offset, size,
438 is_signed, FILTER_OTHER);
439 if (ret)
440 break;
441
442 if (event->fields[i]->is_string) {
443 offset += STR_VAR_LEN_MAX;
444 n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
445 } else {
446 offset += sizeof(u64);
447 n_u64++;
448 }
449 }
450
451 event->n_u64 = n_u64;
452
453 return ret;
454 }
455
456 static bool synth_field_signed(char *type)
457 {
458 if (strncmp(type, "u", 1) == 0)
459 return false;
460
461 return true;
462 }
463
464 static int synth_field_is_string(char *type)
465 {
466 if (strstr(type, "char[") != NULL)
467 return true;
468
469 return false;
470 }
471
472 static int synth_field_string_size(char *type)
473 {
474 char buf[4], *end, *start;
475 unsigned int len;
476 int size, err;
477
478 start = strstr(type, "char[");
479 if (start == NULL)
480 return -EINVAL;
481 start += strlen("char[");
482
483 end = strchr(type, ']');
484 if (!end || end < start)
485 return -EINVAL;
486
487 len = end - start;
488 if (len > 3)
489 return -EINVAL;
490
491 strncpy(buf, start, len);
492 buf[len] = '\0';
493
494 err = kstrtouint(buf, 0, &size);
495 if (err)
496 return err;
497
498 if (size > STR_VAR_LEN_MAX)
499 return -EINVAL;
500
501 return size;
502 }
503
504 static int synth_field_size(char *type)
505 {
506 int size = 0;
507
508 if (strcmp(type, "s64") == 0)
509 size = sizeof(s64);
510 else if (strcmp(type, "u64") == 0)
511 size = sizeof(u64);
512 else if (strcmp(type, "s32") == 0)
513 size = sizeof(s32);
514 else if (strcmp(type, "u32") == 0)
515 size = sizeof(u32);
516 else if (strcmp(type, "s16") == 0)
517 size = sizeof(s16);
518 else if (strcmp(type, "u16") == 0)
519 size = sizeof(u16);
520 else if (strcmp(type, "s8") == 0)
521 size = sizeof(s8);
522 else if (strcmp(type, "u8") == 0)
523 size = sizeof(u8);
524 else if (strcmp(type, "char") == 0)
525 size = sizeof(char);
526 else if (strcmp(type, "unsigned char") == 0)
527 size = sizeof(unsigned char);
528 else if (strcmp(type, "int") == 0)
529 size = sizeof(int);
530 else if (strcmp(type, "unsigned int") == 0)
531 size = sizeof(unsigned int);
532 else if (strcmp(type, "long") == 0)
533 size = sizeof(long);
534 else if (strcmp(type, "unsigned long") == 0)
535 size = sizeof(unsigned long);
536 else if (strcmp(type, "pid_t") == 0)
537 size = sizeof(pid_t);
538 else if (synth_field_is_string(type))
539 size = synth_field_string_size(type);
540
541 return size;
542 }
543
544 static const char *synth_field_fmt(char *type)
545 {
546 const char *fmt = "%llu";
547
548 if (strcmp(type, "s64") == 0)
549 fmt = "%lld";
550 else if (strcmp(type, "u64") == 0)
551 fmt = "%llu";
552 else if (strcmp(type, "s32") == 0)
553 fmt = "%d";
554 else if (strcmp(type, "u32") == 0)
555 fmt = "%u";
556 else if (strcmp(type, "s16") == 0)
557 fmt = "%d";
558 else if (strcmp(type, "u16") == 0)
559 fmt = "%u";
560 else if (strcmp(type, "s8") == 0)
561 fmt = "%d";
562 else if (strcmp(type, "u8") == 0)
563 fmt = "%u";
564 else if (strcmp(type, "char") == 0)
565 fmt = "%d";
566 else if (strcmp(type, "unsigned char") == 0)
567 fmt = "%u";
568 else if (strcmp(type, "int") == 0)
569 fmt = "%d";
570 else if (strcmp(type, "unsigned int") == 0)
571 fmt = "%u";
572 else if (strcmp(type, "long") == 0)
573 fmt = "%ld";
574 else if (strcmp(type, "unsigned long") == 0)
575 fmt = "%lu";
576 else if (strcmp(type, "pid_t") == 0)
577 fmt = "%d";
578 else if (synth_field_is_string(type))
579 fmt = "%s";
580
581 return fmt;
582 }
583
584 static enum print_line_t print_synth_event(struct trace_iterator *iter,
585 int flags,
586 struct trace_event *event)
587 {
588 struct trace_array *tr = iter->tr;
589 struct trace_seq *s = &iter->seq;
590 struct synth_trace_event *entry;
591 struct synth_event *se;
592 unsigned int i, n_u64;
593 char print_fmt[32];
594 const char *fmt;
595
596 entry = (struct synth_trace_event *)iter->ent;
597 se = container_of(event, struct synth_event, call.event);
598
599 trace_seq_printf(s, "%s: ", se->name);
600
601 for (i = 0, n_u64 = 0; i < se->n_fields; i++) {
602 if (trace_seq_has_overflowed(s))
603 goto end;
604
605 fmt = synth_field_fmt(se->fields[i]->type);
606
607 /* parameter types */
608 if (tr->trace_flags & TRACE_ITER_VERBOSE)
609 trace_seq_printf(s, "%s ", fmt);
610
611 snprintf(print_fmt, sizeof(print_fmt), "%%s=%s%%s", fmt);
612
613 /* parameter values */
614 if (se->fields[i]->is_string) {
615 trace_seq_printf(s, print_fmt, se->fields[i]->name,
616 (char *)&entry->fields[n_u64],
617 i == se->n_fields - 1 ? "" : " ");
618 n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
619 } else {
620 trace_seq_printf(s, print_fmt, se->fields[i]->name,
621 entry->fields[n_u64],
622 i == se->n_fields - 1 ? "" : " ");
623 n_u64++;
624 }
625 }
626 end:
627 trace_seq_putc(s, '\n');
628
629 return trace_handle_return(s);
630 }
631
632 static struct trace_event_functions synth_event_funcs = {
633 .trace = print_synth_event
634 };
635
636 static notrace void trace_event_raw_event_synth(void *__data,
637 u64 *var_ref_vals,
638 unsigned int var_ref_idx)
639 {
640 struct trace_event_file *trace_file = __data;
641 struct synth_trace_event *entry;
642 struct trace_event_buffer fbuffer;
643 struct ring_buffer *buffer;
644 struct synth_event *event;
645 unsigned int i, n_u64;
646 int fields_size = 0;
647
648 event = trace_file->event_call->data;
649
650 if (trace_trigger_soft_disabled(trace_file))
651 return;
652
653 fields_size = event->n_u64 * sizeof(u64);
654
655 /*
656 * Avoid ring buffer recursion detection, as this event
657 * is being performed within another event.
658 */
659 buffer = trace_file->tr->trace_buffer.buffer;
660 ring_buffer_nest_start(buffer);
661
662 entry = trace_event_buffer_reserve(&fbuffer, trace_file,
663 sizeof(*entry) + fields_size);
664 if (!entry)
665 goto out;
666
667 for (i = 0, n_u64 = 0; i < event->n_fields; i++) {
668 if (event->fields[i]->is_string) {
669 char *str_val = (char *)(long)var_ref_vals[var_ref_idx + i];
670 char *str_field = (char *)&entry->fields[n_u64];
671
672 strscpy(str_field, str_val, STR_VAR_LEN_MAX);
673 n_u64 += STR_VAR_LEN_MAX / sizeof(u64);
674 } else {
675 entry->fields[n_u64] = var_ref_vals[var_ref_idx + i];
676 n_u64++;
677 }
678 }
679
680 trace_event_buffer_commit(&fbuffer);
681 out:
682 ring_buffer_nest_end(buffer);
683 }
684
685 static void free_synth_event_print_fmt(struct trace_event_call *call)
686 {
687 if (call) {
688 kfree(call->print_fmt);
689 call->print_fmt = NULL;
690 }
691 }
692
693 static int __set_synth_event_print_fmt(struct synth_event *event,
694 char *buf, int len)
695 {
696 const char *fmt;
697 int pos = 0;
698 int i;
699
700 /* When len=0, we just calculate the needed length */
701 #define LEN_OR_ZERO (len ? len - pos : 0)
702
703 pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
704 for (i = 0; i < event->n_fields; i++) {
705 fmt = synth_field_fmt(event->fields[i]->type);
706 pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s%s",
707 event->fields[i]->name, fmt,
708 i == event->n_fields - 1 ? "" : ", ");
709 }
710 pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
711
712 for (i = 0; i < event->n_fields; i++) {
713 pos += snprintf(buf + pos, LEN_OR_ZERO,
714 ", REC->%s", event->fields[i]->name);
715 }
716
717 #undef LEN_OR_ZERO
718
719 /* return the length of print_fmt */
720 return pos;
721 }
722
723 static int set_synth_event_print_fmt(struct trace_event_call *call)
724 {
725 struct synth_event *event = call->data;
726 char *print_fmt;
727 int len;
728
729 /* First: called with 0 length to calculate the needed length */
730 len = __set_synth_event_print_fmt(event, NULL, 0);
731
732 print_fmt = kmalloc(len + 1, GFP_KERNEL);
733 if (!print_fmt)
734 return -ENOMEM;
735
736 /* Second: actually write the @print_fmt */
737 __set_synth_event_print_fmt(event, print_fmt, len + 1);
738 call->print_fmt = print_fmt;
739
740 return 0;
741 }
742
743 static void free_synth_field(struct synth_field *field)
744 {
745 kfree(field->type);
746 kfree(field->name);
747 kfree(field);
748 }
749
750 static struct synth_field *parse_synth_field(char *field_type,
751 char *field_name)
752 {
753 struct synth_field *field;
754 int len, ret = 0;
755 char *array;
756
757 if (field_type[0] == ';')
758 field_type++;
759
760 len = strlen(field_name);
761 if (field_name[len - 1] == ';')
762 field_name[len - 1] = '\0';
763
764 field = kzalloc(sizeof(*field), GFP_KERNEL);
765 if (!field)
766 return ERR_PTR(-ENOMEM);
767
768 len = strlen(field_type) + 1;
769 array = strchr(field_name, '[');
770 if (array)
771 len += strlen(array);
772 field->type = kzalloc(len, GFP_KERNEL);
773 if (!field->type) {
774 ret = -ENOMEM;
775 goto free;
776 }
777 strcat(field->type, field_type);
778 if (array) {
779 strcat(field->type, array);
780 *array = '\0';
781 }
782
783 field->size = synth_field_size(field->type);
784 if (!field->size) {
785 ret = -EINVAL;
786 goto free;
787 }
788
789 if (synth_field_is_string(field->type))
790 field->is_string = true;
791
792 field->is_signed = synth_field_signed(field->type);
793
794 field->name = kstrdup(field_name, GFP_KERNEL);
795 if (!field->name) {
796 ret = -ENOMEM;
797 goto free;
798 }
799 out:
800 return field;
801 free:
802 free_synth_field(field);
803 field = ERR_PTR(ret);
804 goto out;
805 }
806
807 static void free_synth_tracepoint(struct tracepoint *tp)
808 {
809 if (!tp)
810 return;
811
812 kfree(tp->name);
813 kfree(tp);
814 }
815
816 static struct tracepoint *alloc_synth_tracepoint(char *name)
817 {
818 struct tracepoint *tp;
819
820 tp = kzalloc(sizeof(*tp), GFP_KERNEL);
821 if (!tp)
822 return ERR_PTR(-ENOMEM);
823
824 tp->name = kstrdup(name, GFP_KERNEL);
825 if (!tp->name) {
826 kfree(tp);
827 return ERR_PTR(-ENOMEM);
828 }
829
830 return tp;
831 }
832
833 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals,
834 unsigned int var_ref_idx);
835
836 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals,
837 unsigned int var_ref_idx)
838 {
839 struct tracepoint *tp = event->tp;
840
841 if (unlikely(atomic_read(&tp->key.enabled) > 0)) {
842 struct tracepoint_func *probe_func_ptr;
843 synth_probe_func_t probe_func;
844 void *__data;
845
846 if (!(cpu_online(raw_smp_processor_id())))
847 return;
848
849 probe_func_ptr = rcu_dereference_sched((tp)->funcs);
850 if (probe_func_ptr) {
851 do {
852 probe_func = probe_func_ptr->func;
853 __data = probe_func_ptr->data;
854 probe_func(__data, var_ref_vals, var_ref_idx);
855 } while ((++probe_func_ptr)->func);
856 }
857 }
858 }
859
860 static struct synth_event *find_synth_event(const char *name)
861 {
862 struct synth_event *event;
863
864 list_for_each_entry(event, &synth_event_list, list) {
865 if (strcmp(event->name, name) == 0)
866 return event;
867 }
868
869 return NULL;
870 }
871
872 static int register_synth_event(struct synth_event *event)
873 {
874 struct trace_event_call *call = &event->call;
875 int ret = 0;
876
877 event->call.class = &event->class;
878 event->class.system = kstrdup(SYNTH_SYSTEM, GFP_KERNEL);
879 if (!event->class.system) {
880 ret = -ENOMEM;
881 goto out;
882 }
883
884 event->tp = alloc_synth_tracepoint(event->name);
885 if (IS_ERR(event->tp)) {
886 ret = PTR_ERR(event->tp);
887 event->tp = NULL;
888 goto out;
889 }
890
891 INIT_LIST_HEAD(&call->class->fields);
892 call->event.funcs = &synth_event_funcs;
893 call->class->define_fields = synth_event_define_fields;
894
895 ret = register_trace_event(&call->event);
896 if (!ret) {
897 ret = -ENODEV;
898 goto out;
899 }
900 call->flags = TRACE_EVENT_FL_TRACEPOINT;
901 call->class->reg = trace_event_reg;
902 call->class->probe = trace_event_raw_event_synth;
903 call->data = event;
904 call->tp = event->tp;
905
906 ret = trace_add_event_call(call);
907 if (ret) {
908 pr_warn("Failed to register synthetic event: %s\n",
909 trace_event_name(call));
910 goto err;
911 }
912
913 ret = set_synth_event_print_fmt(call);
914 if (ret < 0) {
915 trace_remove_event_call(call);
916 goto err;
917 }
918 out:
919 return ret;
920 err:
921 unregister_trace_event(&call->event);
922 goto out;
923 }
924
925 static int unregister_synth_event(struct synth_event *event)
926 {
927 struct trace_event_call *call = &event->call;
928 int ret;
929
930 ret = trace_remove_event_call(call);
931
932 return ret;
933 }
934
935 static void free_synth_event(struct synth_event *event)
936 {
937 unsigned int i;
938
939 if (!event)
940 return;
941
942 for (i = 0; i < event->n_fields; i++)
943 free_synth_field(event->fields[i]);
944
945 kfree(event->fields);
946 kfree(event->name);
947 kfree(event->class.system);
948 free_synth_tracepoint(event->tp);
949 free_synth_event_print_fmt(&event->call);
950 kfree(event);
951 }
952
953 static struct synth_event *alloc_synth_event(char *event_name, int n_fields,
954 struct synth_field **fields)
955 {
956 struct synth_event *event;
957 unsigned int i;
958
959 event = kzalloc(sizeof(*event), GFP_KERNEL);
960 if (!event) {
961 event = ERR_PTR(-ENOMEM);
962 goto out;
963 }
964
965 event->name = kstrdup(event_name, GFP_KERNEL);
966 if (!event->name) {
967 kfree(event);
968 event = ERR_PTR(-ENOMEM);
969 goto out;
970 }
971
972 event->fields = kcalloc(n_fields, sizeof(*event->fields), GFP_KERNEL);
973 if (!event->fields) {
974 free_synth_event(event);
975 event = ERR_PTR(-ENOMEM);
976 goto out;
977 }
978
979 for (i = 0; i < n_fields; i++)
980 event->fields[i] = fields[i];
981
982 event->n_fields = n_fields;
983 out:
984 return event;
985 }
986
987 static void action_trace(struct hist_trigger_data *hist_data,
988 struct tracing_map_elt *elt, void *rec,
989 struct ring_buffer_event *rbe,
990 struct action_data *data, u64 *var_ref_vals)
991 {
992 struct synth_event *event = data->onmatch.synth_event;
993
994 trace_synth(event, var_ref_vals, data->onmatch.var_ref_idx);
995 }
996
997 struct hist_var_data {
998 struct list_head list;
999 struct hist_trigger_data *hist_data;
1000 };
1001
1002 static void add_or_delete_synth_event(struct synth_event *event, int delete)
1003 {
1004 if (delete)
1005 free_synth_event(event);
1006 else {
1007 mutex_lock(&synth_event_mutex);
1008 if (!find_synth_event(event->name))
1009 list_add(&event->list, &synth_event_list);
1010 else
1011 free_synth_event(event);
1012 mutex_unlock(&synth_event_mutex);
1013 }
1014 }
1015
1016 static int create_synth_event(int argc, char **argv)
1017 {
1018 struct synth_field *field, *fields[SYNTH_FIELDS_MAX];
1019 struct synth_event *event = NULL;
1020 bool delete_event = false;
1021 int i, n_fields = 0, ret = 0;
1022 char *name;
1023
1024 mutex_lock(&synth_event_mutex);
1025
1026 /*
1027 * Argument syntax:
1028 * - Add synthetic event: <event_name> field[;field] ...
1029 * - Remove synthetic event: !<event_name> field[;field] ...
1030 * where 'field' = type field_name
1031 */
1032 if (argc < 1) {
1033 ret = -EINVAL;
1034 goto out;
1035 }
1036
1037 name = argv[0];
1038 if (name[0] == '!') {
1039 delete_event = true;
1040 name++;
1041 }
1042
1043 event = find_synth_event(name);
1044 if (event) {
1045 if (delete_event) {
1046 if (event->ref) {
1047 event = NULL;
1048 ret = -EBUSY;
1049 goto out;
1050 }
1051 list_del(&event->list);
1052 goto out;
1053 }
1054 event = NULL;
1055 ret = -EEXIST;
1056 goto out;
1057 } else if (delete_event)
1058 goto out;
1059
1060 if (argc < 2) {
1061 ret = -EINVAL;
1062 goto out;
1063 }
1064
1065 for (i = 1; i < argc - 1; i++) {
1066 if (strcmp(argv[i], ";") == 0)
1067 continue;
1068 if (n_fields == SYNTH_FIELDS_MAX) {
1069 ret = -EINVAL;
1070 goto err;
1071 }
1072
1073 field = parse_synth_field(argv[i], argv[i + 1]);
1074 if (IS_ERR(field)) {
1075 ret = PTR_ERR(field);
1076 goto err;
1077 }
1078 fields[n_fields] = field;
1079 i++; n_fields++;
1080 }
1081
1082 if (i < argc) {
1083 ret = -EINVAL;
1084 goto err;
1085 }
1086
1087 event = alloc_synth_event(name, n_fields, fields);
1088 if (IS_ERR(event)) {
1089 ret = PTR_ERR(event);
1090 event = NULL;
1091 goto err;
1092 }
1093 out:
1094 mutex_unlock(&synth_event_mutex);
1095
1096 if (event) {
1097 if (delete_event) {
1098 ret = unregister_synth_event(event);
1099 add_or_delete_synth_event(event, !ret);
1100 } else {
1101 ret = register_synth_event(event);
1102 add_or_delete_synth_event(event, ret);
1103 }
1104 }
1105
1106 return ret;
1107 err:
1108 mutex_unlock(&synth_event_mutex);
1109
1110 for (i = 0; i < n_fields; i++)
1111 free_synth_field(fields[i]);
1112 free_synth_event(event);
1113
1114 return ret;
1115 }
1116
1117 static int release_all_synth_events(void)
1118 {
1119 struct list_head release_events;
1120 struct synth_event *event, *e;
1121 int ret = 0;
1122
1123 INIT_LIST_HEAD(&release_events);
1124
1125 mutex_lock(&synth_event_mutex);
1126
1127 list_for_each_entry(event, &synth_event_list, list) {
1128 if (event->ref) {
1129 mutex_unlock(&synth_event_mutex);
1130 return -EBUSY;
1131 }
1132 }
1133
1134 list_splice_init(&event->list, &release_events);
1135
1136 mutex_unlock(&synth_event_mutex);
1137
1138 list_for_each_entry_safe(event, e, &release_events, list) {
1139 list_del(&event->list);
1140
1141 ret = unregister_synth_event(event);
1142 add_or_delete_synth_event(event, !ret);
1143 }
1144
1145 return ret;
1146 }
1147
1148
1149 static void *synth_events_seq_start(struct seq_file *m, loff_t *pos)
1150 {
1151 mutex_lock(&synth_event_mutex);
1152
1153 return seq_list_start(&synth_event_list, *pos);
1154 }
1155
1156 static void *synth_events_seq_next(struct seq_file *m, void *v, loff_t *pos)
1157 {
1158 return seq_list_next(v, &synth_event_list, pos);
1159 }
1160
1161 static void synth_events_seq_stop(struct seq_file *m, void *v)
1162 {
1163 mutex_unlock(&synth_event_mutex);
1164 }
1165
1166 static int synth_events_seq_show(struct seq_file *m, void *v)
1167 {
1168 struct synth_field *field;
1169 struct synth_event *event = v;
1170 unsigned int i;
1171
1172 seq_printf(m, "%s\t", event->name);
1173
1174 for (i = 0; i < event->n_fields; i++) {
1175 field = event->fields[i];
1176
1177 /* parameter values */
1178 seq_printf(m, "%s %s%s", field->type, field->name,
1179 i == event->n_fields - 1 ? "" : "; ");
1180 }
1181
1182 seq_putc(m, '\n');
1183
1184 return 0;
1185 }
1186
1187 static const struct seq_operations synth_events_seq_op = {
1188 .start = synth_events_seq_start,
1189 .next = synth_events_seq_next,
1190 .stop = synth_events_seq_stop,
1191 .show = synth_events_seq_show
1192 };
1193
1194 static int synth_events_open(struct inode *inode, struct file *file)
1195 {
1196 int ret;
1197
1198 if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
1199 ret = release_all_synth_events();
1200 if (ret < 0)
1201 return ret;
1202 }
1203
1204 return seq_open(file, &synth_events_seq_op);
1205 }
1206
1207 static ssize_t synth_events_write(struct file *file,
1208 const char __user *buffer,
1209 size_t count, loff_t *ppos)
1210 {
1211 return trace_parse_run_command(file, buffer, count, ppos,
1212 create_synth_event);
1213 }
1214
1215 static const struct file_operations synth_events_fops = {
1216 .open = synth_events_open,
1217 .write = synth_events_write,
1218 .read = seq_read,
1219 .llseek = seq_lseek,
1220 .release = seq_release,
1221 };
1222
1223 static u64 hist_field_timestamp(struct hist_field *hist_field,
1224 struct tracing_map_elt *elt,
1225 struct ring_buffer_event *rbe,
1226 void *event)
1227 {
1228 struct hist_trigger_data *hist_data = hist_field->hist_data;
1229 struct trace_array *tr = hist_data->event_file->tr;
1230
1231 u64 ts = ring_buffer_event_time_stamp(rbe);
1232
1233 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr))
1234 ts = ns2usecs(ts);
1235
1236 return ts;
1237 }
1238
1239 static u64 hist_field_cpu(struct hist_field *hist_field,
1240 struct tracing_map_elt *elt,
1241 struct ring_buffer_event *rbe,
1242 void *event)
1243 {
1244 int cpu = smp_processor_id();
1245
1246 return cpu;
1247 }
1248
1249 static struct hist_field *
1250 check_field_for_var_ref(struct hist_field *hist_field,
1251 struct hist_trigger_data *var_data,
1252 unsigned int var_idx)
1253 {
1254 struct hist_field *found = NULL;
1255
1256 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF) {
1257 if (hist_field->var.idx == var_idx &&
1258 hist_field->var.hist_data == var_data) {
1259 found = hist_field;
1260 }
1261 }
1262
1263 return found;
1264 }
1265
1266 static struct hist_field *
1267 check_field_for_var_refs(struct hist_trigger_data *hist_data,
1268 struct hist_field *hist_field,
1269 struct hist_trigger_data *var_data,
1270 unsigned int var_idx,
1271 unsigned int level)
1272 {
1273 struct hist_field *found = NULL;
1274 unsigned int i;
1275
1276 if (level > 3)
1277 return found;
1278
1279 if (!hist_field)
1280 return found;
1281
1282 found = check_field_for_var_ref(hist_field, var_data, var_idx);
1283 if (found)
1284 return found;
1285
1286 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
1287 struct hist_field *operand;
1288
1289 operand = hist_field->operands[i];
1290 found = check_field_for_var_refs(hist_data, operand, var_data,
1291 var_idx, level + 1);
1292 if (found)
1293 return found;
1294 }
1295
1296 return found;
1297 }
1298
1299 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data,
1300 struct hist_trigger_data *var_data,
1301 unsigned int var_idx)
1302 {
1303 struct hist_field *hist_field, *found = NULL;
1304 unsigned int i;
1305
1306 for_each_hist_field(i, hist_data) {
1307 hist_field = hist_data->fields[i];
1308 found = check_field_for_var_refs(hist_data, hist_field,
1309 var_data, var_idx, 0);
1310 if (found)
1311 return found;
1312 }
1313
1314 for (i = 0; i < hist_data->n_synth_var_refs; i++) {
1315 hist_field = hist_data->synth_var_refs[i];
1316 found = check_field_for_var_refs(hist_data, hist_field,
1317 var_data, var_idx, 0);
1318 if (found)
1319 return found;
1320 }
1321
1322 return found;
1323 }
1324
1325 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data,
1326 unsigned int var_idx)
1327 {
1328 struct trace_array *tr = hist_data->event_file->tr;
1329 struct hist_field *found = NULL;
1330 struct hist_var_data *var_data;
1331
1332 list_for_each_entry(var_data, &tr->hist_vars, list) {
1333 if (var_data->hist_data == hist_data)
1334 continue;
1335 found = find_var_ref(var_data->hist_data, hist_data, var_idx);
1336 if (found)
1337 break;
1338 }
1339
1340 return found;
1341 }
1342
1343 static bool check_var_refs(struct hist_trigger_data *hist_data)
1344 {
1345 struct hist_field *field;
1346 bool found = false;
1347 int i;
1348
1349 for_each_hist_field(i, hist_data) {
1350 field = hist_data->fields[i];
1351 if (field && field->flags & HIST_FIELD_FL_VAR) {
1352 if (find_any_var_ref(hist_data, field->var.idx)) {
1353 found = true;
1354 break;
1355 }
1356 }
1357 }
1358
1359 return found;
1360 }
1361
1362 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data)
1363 {
1364 struct trace_array *tr = hist_data->event_file->tr;
1365 struct hist_var_data *var_data, *found = NULL;
1366
1367 list_for_each_entry(var_data, &tr->hist_vars, list) {
1368 if (var_data->hist_data == hist_data) {
1369 found = var_data;
1370 break;
1371 }
1372 }
1373
1374 return found;
1375 }
1376
1377 static bool field_has_hist_vars(struct hist_field *hist_field,
1378 unsigned int level)
1379 {
1380 int i;
1381
1382 if (level > 3)
1383 return false;
1384
1385 if (!hist_field)
1386 return false;
1387
1388 if (hist_field->flags & HIST_FIELD_FL_VAR ||
1389 hist_field->flags & HIST_FIELD_FL_VAR_REF)
1390 return true;
1391
1392 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) {
1393 struct hist_field *operand;
1394
1395 operand = hist_field->operands[i];
1396 if (field_has_hist_vars(operand, level + 1))
1397 return true;
1398 }
1399
1400 return false;
1401 }
1402
1403 static bool has_hist_vars(struct hist_trigger_data *hist_data)
1404 {
1405 struct hist_field *hist_field;
1406 int i;
1407
1408 for_each_hist_field(i, hist_data) {
1409 hist_field = hist_data->fields[i];
1410 if (field_has_hist_vars(hist_field, 0))
1411 return true;
1412 }
1413
1414 return false;
1415 }
1416
1417 static int save_hist_vars(struct hist_trigger_data *hist_data)
1418 {
1419 struct trace_array *tr = hist_data->event_file->tr;
1420 struct hist_var_data *var_data;
1421
1422 var_data = find_hist_vars(hist_data);
1423 if (var_data)
1424 return 0;
1425
1426 if (trace_array_get(tr) < 0)
1427 return -ENODEV;
1428
1429 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL);
1430 if (!var_data) {
1431 trace_array_put(tr);
1432 return -ENOMEM;
1433 }
1434
1435 var_data->hist_data = hist_data;
1436 list_add(&var_data->list, &tr->hist_vars);
1437
1438 return 0;
1439 }
1440
1441 static void remove_hist_vars(struct hist_trigger_data *hist_data)
1442 {
1443 struct trace_array *tr = hist_data->event_file->tr;
1444 struct hist_var_data *var_data;
1445
1446 var_data = find_hist_vars(hist_data);
1447 if (!var_data)
1448 return;
1449
1450 if (WARN_ON(check_var_refs(hist_data)))
1451 return;
1452
1453 list_del(&var_data->list);
1454
1455 kfree(var_data);
1456
1457 trace_array_put(tr);
1458 }
1459
1460 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data,
1461 const char *var_name)
1462 {
1463 struct hist_field *hist_field, *found = NULL;
1464 int i;
1465
1466 for_each_hist_field(i, hist_data) {
1467 hist_field = hist_data->fields[i];
1468 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR &&
1469 strcmp(hist_field->var.name, var_name) == 0) {
1470 found = hist_field;
1471 break;
1472 }
1473 }
1474
1475 return found;
1476 }
1477
1478 static struct hist_field *find_var(struct hist_trigger_data *hist_data,
1479 struct trace_event_file *file,
1480 const char *var_name)
1481 {
1482 struct hist_trigger_data *test_data;
1483 struct event_trigger_data *test;
1484 struct hist_field *hist_field;
1485
1486 hist_field = find_var_field(hist_data, var_name);
1487 if (hist_field)
1488 return hist_field;
1489
1490 list_for_each_entry_rcu(test, &file->triggers, list) {
1491 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
1492 test_data = test->private_data;
1493 hist_field = find_var_field(test_data, var_name);
1494 if (hist_field)
1495 return hist_field;
1496 }
1497 }
1498
1499 return NULL;
1500 }
1501
1502 static struct trace_event_file *find_var_file(struct trace_array *tr,
1503 char *system,
1504 char *event_name,
1505 char *var_name)
1506 {
1507 struct hist_trigger_data *var_hist_data;
1508 struct hist_var_data *var_data;
1509 struct trace_event_file *file, *found = NULL;
1510
1511 if (system)
1512 return find_event_file(tr, system, event_name);
1513
1514 list_for_each_entry(var_data, &tr->hist_vars, list) {
1515 var_hist_data = var_data->hist_data;
1516 file = var_hist_data->event_file;
1517 if (file == found)
1518 continue;
1519
1520 if (find_var_field(var_hist_data, var_name)) {
1521 if (found) {
1522 hist_err_event("Variable name not unique, need to use fully qualified name (subsys.event.var) for variable: ", system, event_name, var_name);
1523 return NULL;
1524 }
1525
1526 found = file;
1527 }
1528 }
1529
1530 return found;
1531 }
1532
1533 static struct hist_field *find_file_var(struct trace_event_file *file,
1534 const char *var_name)
1535 {
1536 struct hist_trigger_data *test_data;
1537 struct event_trigger_data *test;
1538 struct hist_field *hist_field;
1539
1540 list_for_each_entry_rcu(test, &file->triggers, list) {
1541 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
1542 test_data = test->private_data;
1543 hist_field = find_var_field(test_data, var_name);
1544 if (hist_field)
1545 return hist_field;
1546 }
1547 }
1548
1549 return NULL;
1550 }
1551
1552 static struct hist_field *
1553 find_match_var(struct hist_trigger_data *hist_data, char *var_name)
1554 {
1555 struct trace_array *tr = hist_data->event_file->tr;
1556 struct hist_field *hist_field, *found = NULL;
1557 struct trace_event_file *file;
1558 unsigned int i;
1559
1560 for (i = 0; i < hist_data->n_actions; i++) {
1561 struct action_data *data = hist_data->actions[i];
1562
1563 if (data->fn == action_trace) {
1564 char *system = data->onmatch.match_event_system;
1565 char *event_name = data->onmatch.match_event;
1566
1567 file = find_var_file(tr, system, event_name, var_name);
1568 if (!file)
1569 continue;
1570 hist_field = find_file_var(file, var_name);
1571 if (hist_field) {
1572 if (found) {
1573 hist_err_event("Variable name not unique, need to use fully qualified name (subsys.event.var) for variable: ", system, event_name, var_name);
1574 return ERR_PTR(-EINVAL);
1575 }
1576
1577 found = hist_field;
1578 }
1579 }
1580 }
1581 return found;
1582 }
1583
1584 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data,
1585 char *system,
1586 char *event_name,
1587 char *var_name)
1588 {
1589 struct trace_array *tr = hist_data->event_file->tr;
1590 struct hist_field *hist_field = NULL;
1591 struct trace_event_file *file;
1592
1593 if (!system || !event_name) {
1594 hist_field = find_match_var(hist_data, var_name);
1595 if (IS_ERR(hist_field))
1596 return NULL;
1597 if (hist_field)
1598 return hist_field;
1599 }
1600
1601 file = find_var_file(tr, system, event_name, var_name);
1602 if (!file)
1603 return NULL;
1604
1605 hist_field = find_file_var(file, var_name);
1606
1607 return hist_field;
1608 }
1609
1610 struct hist_elt_data {
1611 char *comm;
1612 u64 *var_ref_vals;
1613 char *field_var_str[SYNTH_FIELDS_MAX];
1614 };
1615
1616 static u64 hist_field_var_ref(struct hist_field *hist_field,
1617 struct tracing_map_elt *elt,
1618 struct ring_buffer_event *rbe,
1619 void *event)
1620 {
1621 struct hist_elt_data *elt_data;
1622 u64 var_val = 0;
1623
1624 elt_data = elt->private_data;
1625 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx];
1626
1627 return var_val;
1628 }
1629
1630 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key,
1631 u64 *var_ref_vals, bool self)
1632 {
1633 struct hist_trigger_data *var_data;
1634 struct tracing_map_elt *var_elt;
1635 struct hist_field *hist_field;
1636 unsigned int i, var_idx;
1637 bool resolved = true;
1638 u64 var_val = 0;
1639
1640 for (i = 0; i < hist_data->n_var_refs; i++) {
1641 hist_field = hist_data->var_refs[i];
1642 var_idx = hist_field->var.idx;
1643 var_data = hist_field->var.hist_data;
1644
1645 if (var_data == NULL) {
1646 resolved = false;
1647 break;
1648 }
1649
1650 if ((self && var_data != hist_data) ||
1651 (!self && var_data == hist_data))
1652 continue;
1653
1654 var_elt = tracing_map_lookup(var_data->map, key);
1655 if (!var_elt) {
1656 resolved = false;
1657 break;
1658 }
1659
1660 if (!tracing_map_var_set(var_elt, var_idx)) {
1661 resolved = false;
1662 break;
1663 }
1664
1665 if (self || !hist_field->read_once)
1666 var_val = tracing_map_read_var(var_elt, var_idx);
1667 else
1668 var_val = tracing_map_read_var_once(var_elt, var_idx);
1669
1670 var_ref_vals[i] = var_val;
1671 }
1672
1673 return resolved;
1674 }
1675
1676 static const char *hist_field_name(struct hist_field *field,
1677 unsigned int level)
1678 {
1679 const char *field_name = "";
1680
1681 if (level > 1)
1682 return field_name;
1683
1684 if (field->field)
1685 field_name = field->field->name;
1686 else if (field->flags & HIST_FIELD_FL_LOG2 ||
1687 field->flags & HIST_FIELD_FL_ALIAS)
1688 field_name = hist_field_name(field->operands[0], ++level);
1689 else if (field->flags & HIST_FIELD_FL_CPU)
1690 field_name = "cpu";
1691 else if (field->flags & HIST_FIELD_FL_EXPR ||
1692 field->flags & HIST_FIELD_FL_VAR_REF) {
1693 if (field->system) {
1694 static char full_name[MAX_FILTER_STR_VAL];
1695
1696 strcat(full_name, field->system);
1697 strcat(full_name, ".");
1698 strcat(full_name, field->event_name);
1699 strcat(full_name, ".");
1700 strcat(full_name, field->name);
1701 field_name = full_name;
1702 } else
1703 field_name = field->name;
1704 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP)
1705 field_name = "common_timestamp";
1706
1707 if (field_name == NULL)
1708 field_name = "";
1709
1710 return field_name;
1711 }
1712
1713 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed)
1714 {
1715 hist_field_fn_t fn = NULL;
1716
1717 switch (field_size) {
1718 case 8:
1719 if (field_is_signed)
1720 fn = hist_field_s64;
1721 else
1722 fn = hist_field_u64;
1723 break;
1724 case 4:
1725 if (field_is_signed)
1726 fn = hist_field_s32;
1727 else
1728 fn = hist_field_u32;
1729 break;
1730 case 2:
1731 if (field_is_signed)
1732 fn = hist_field_s16;
1733 else
1734 fn = hist_field_u16;
1735 break;
1736 case 1:
1737 if (field_is_signed)
1738 fn = hist_field_s8;
1739 else
1740 fn = hist_field_u8;
1741 break;
1742 }
1743
1744 return fn;
1745 }
1746
1747 static int parse_map_size(char *str)
1748 {
1749 unsigned long size, map_bits;
1750 int ret;
1751
1752 strsep(&str, "=");
1753 if (!str) {
1754 ret = -EINVAL;
1755 goto out;
1756 }
1757
1758 ret = kstrtoul(str, 0, &size);
1759 if (ret)
1760 goto out;
1761
1762 map_bits = ilog2(roundup_pow_of_two(size));
1763 if (map_bits < TRACING_MAP_BITS_MIN ||
1764 map_bits > TRACING_MAP_BITS_MAX)
1765 ret = -EINVAL;
1766 else
1767 ret = map_bits;
1768 out:
1769 return ret;
1770 }
1771
1772 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs)
1773 {
1774 unsigned int i;
1775
1776 if (!attrs)
1777 return;
1778
1779 for (i = 0; i < attrs->n_assignments; i++)
1780 kfree(attrs->assignment_str[i]);
1781
1782 for (i = 0; i < attrs->n_actions; i++)
1783 kfree(attrs->action_str[i]);
1784
1785 kfree(attrs->name);
1786 kfree(attrs->sort_key_str);
1787 kfree(attrs->keys_str);
1788 kfree(attrs->vals_str);
1789 kfree(attrs->clock);
1790 kfree(attrs);
1791 }
1792
1793 static int parse_action(char *str, struct hist_trigger_attrs *attrs)
1794 {
1795 int ret = -EINVAL;
1796
1797 if (attrs->n_actions >= HIST_ACTIONS_MAX)
1798 return ret;
1799
1800 if ((strncmp(str, "onmatch(", strlen("onmatch(")) == 0) ||
1801 (strncmp(str, "onmax(", strlen("onmax(")) == 0)) {
1802 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL);
1803 if (!attrs->action_str[attrs->n_actions]) {
1804 ret = -ENOMEM;
1805 return ret;
1806 }
1807 attrs->n_actions++;
1808 ret = 0;
1809 }
1810
1811 return ret;
1812 }
1813
1814 static int parse_assignment(char *str, struct hist_trigger_attrs *attrs)
1815 {
1816 int ret = 0;
1817
1818 if ((strncmp(str, "key=", strlen("key=")) == 0) ||
1819 (strncmp(str, "keys=", strlen("keys=")) == 0)) {
1820 attrs->keys_str = kstrdup(str, GFP_KERNEL);
1821 if (!attrs->keys_str) {
1822 ret = -ENOMEM;
1823 goto out;
1824 }
1825 } else if ((strncmp(str, "val=", strlen("val=")) == 0) ||
1826 (strncmp(str, "vals=", strlen("vals=")) == 0) ||
1827 (strncmp(str, "values=", strlen("values=")) == 0)) {
1828 attrs->vals_str = kstrdup(str, GFP_KERNEL);
1829 if (!attrs->vals_str) {
1830 ret = -ENOMEM;
1831 goto out;
1832 }
1833 } else if (strncmp(str, "sort=", strlen("sort=")) == 0) {
1834 attrs->sort_key_str = kstrdup(str, GFP_KERNEL);
1835 if (!attrs->sort_key_str) {
1836 ret = -ENOMEM;
1837 goto out;
1838 }
1839 } else if (strncmp(str, "name=", strlen("name=")) == 0) {
1840 attrs->name = kstrdup(str, GFP_KERNEL);
1841 if (!attrs->name) {
1842 ret = -ENOMEM;
1843 goto out;
1844 }
1845 } else if (strncmp(str, "clock=", strlen("clock=")) == 0) {
1846 strsep(&str, "=");
1847 if (!str) {
1848 ret = -EINVAL;
1849 goto out;
1850 }
1851
1852 str = strstrip(str);
1853 attrs->clock = kstrdup(str, GFP_KERNEL);
1854 if (!attrs->clock) {
1855 ret = -ENOMEM;
1856 goto out;
1857 }
1858 } else if (strncmp(str, "size=", strlen("size=")) == 0) {
1859 int map_bits = parse_map_size(str);
1860
1861 if (map_bits < 0) {
1862 ret = map_bits;
1863 goto out;
1864 }
1865 attrs->map_bits = map_bits;
1866 } else {
1867 char *assignment;
1868
1869 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) {
1870 hist_err("Too many variables defined: ", str);
1871 ret = -EINVAL;
1872 goto out;
1873 }
1874
1875 assignment = kstrdup(str, GFP_KERNEL);
1876 if (!assignment) {
1877 ret = -ENOMEM;
1878 goto out;
1879 }
1880
1881 attrs->assignment_str[attrs->n_assignments++] = assignment;
1882 }
1883 out:
1884 return ret;
1885 }
1886
1887 static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str)
1888 {
1889 struct hist_trigger_attrs *attrs;
1890 int ret = 0;
1891
1892 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL);
1893 if (!attrs)
1894 return ERR_PTR(-ENOMEM);
1895
1896 while (trigger_str) {
1897 char *str = strsep(&trigger_str, ":");
1898
1899 if (strchr(str, '=')) {
1900 ret = parse_assignment(str, attrs);
1901 if (ret)
1902 goto free;
1903 } else if (strcmp(str, "pause") == 0)
1904 attrs->pause = true;
1905 else if ((strcmp(str, "cont") == 0) ||
1906 (strcmp(str, "continue") == 0))
1907 attrs->cont = true;
1908 else if (strcmp(str, "clear") == 0)
1909 attrs->clear = true;
1910 else {
1911 ret = parse_action(str, attrs);
1912 if (ret)
1913 goto free;
1914 }
1915 }
1916
1917 if (!attrs->keys_str) {
1918 ret = -EINVAL;
1919 goto free;
1920 }
1921
1922 if (!attrs->clock) {
1923 attrs->clock = kstrdup("global", GFP_KERNEL);
1924 if (!attrs->clock) {
1925 ret = -ENOMEM;
1926 goto free;
1927 }
1928 }
1929
1930 return attrs;
1931 free:
1932 destroy_hist_trigger_attrs(attrs);
1933
1934 return ERR_PTR(ret);
1935 }
1936
1937 static inline void save_comm(char *comm, struct task_struct *task)
1938 {
1939 if (!task->pid) {
1940 strcpy(comm, "<idle>");
1941 return;
1942 }
1943
1944 if (WARN_ON_ONCE(task->pid < 0)) {
1945 strcpy(comm, "<XXX>");
1946 return;
1947 }
1948
1949 memcpy(comm, task->comm, TASK_COMM_LEN);
1950 }
1951
1952 static void hist_elt_data_free(struct hist_elt_data *elt_data)
1953 {
1954 unsigned int i;
1955
1956 for (i = 0; i < SYNTH_FIELDS_MAX; i++)
1957 kfree(elt_data->field_var_str[i]);
1958
1959 kfree(elt_data->comm);
1960 kfree(elt_data);
1961 }
1962
1963 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt)
1964 {
1965 struct hist_elt_data *elt_data = elt->private_data;
1966
1967 hist_elt_data_free(elt_data);
1968 }
1969
1970 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
1971 {
1972 struct hist_trigger_data *hist_data = elt->map->private_data;
1973 unsigned int size = TASK_COMM_LEN;
1974 struct hist_elt_data *elt_data;
1975 struct hist_field *key_field;
1976 unsigned int i, n_str;
1977
1978 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
1979 if (!elt_data)
1980 return -ENOMEM;
1981
1982 for_each_hist_key_field(i, hist_data) {
1983 key_field = hist_data->fields[i];
1984
1985 if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
1986 elt_data->comm = kzalloc(size, GFP_KERNEL);
1987 if (!elt_data->comm) {
1988 kfree(elt_data);
1989 return -ENOMEM;
1990 }
1991 break;
1992 }
1993 }
1994
1995 n_str = hist_data->n_field_var_str + hist_data->n_max_var_str;
1996
1997 size = STR_VAR_LEN_MAX;
1998
1999 for (i = 0; i < n_str; i++) {
2000 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL);
2001 if (!elt_data->field_var_str[i]) {
2002 hist_elt_data_free(elt_data);
2003 return -ENOMEM;
2004 }
2005 }
2006
2007 elt->private_data = elt_data;
2008
2009 return 0;
2010 }
2011
2012 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt)
2013 {
2014 struct hist_elt_data *elt_data = elt->private_data;
2015
2016 if (elt_data->comm)
2017 save_comm(elt_data->comm, current);
2018 }
2019
2020 static const struct tracing_map_ops hist_trigger_elt_data_ops = {
2021 .elt_alloc = hist_trigger_elt_data_alloc,
2022 .elt_free = hist_trigger_elt_data_free,
2023 .elt_init = hist_trigger_elt_data_init,
2024 };
2025
2026 static const char *get_hist_field_flags(struct hist_field *hist_field)
2027 {
2028 const char *flags_str = NULL;
2029
2030 if (hist_field->flags & HIST_FIELD_FL_HEX)
2031 flags_str = "hex";
2032 else if (hist_field->flags & HIST_FIELD_FL_SYM)
2033 flags_str = "sym";
2034 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET)
2035 flags_str = "sym-offset";
2036 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME)
2037 flags_str = "execname";
2038 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL)
2039 flags_str = "syscall";
2040 else if (hist_field->flags & HIST_FIELD_FL_LOG2)
2041 flags_str = "log2";
2042 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS)
2043 flags_str = "usecs";
2044
2045 return flags_str;
2046 }
2047
2048 static void expr_field_str(struct hist_field *field, char *expr)
2049 {
2050 if (field->flags & HIST_FIELD_FL_VAR_REF)
2051 strcat(expr, "$");
2052
2053 strcat(expr, hist_field_name(field, 0));
2054
2055 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) {
2056 const char *flags_str = get_hist_field_flags(field);
2057
2058 if (flags_str) {
2059 strcat(expr, ".");
2060 strcat(expr, flags_str);
2061 }
2062 }
2063 }
2064
2065 static char *expr_str(struct hist_field *field, unsigned int level)
2066 {
2067 char *expr;
2068
2069 if (level > 1)
2070 return NULL;
2071
2072 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2073 if (!expr)
2074 return NULL;
2075
2076 if (!field->operands[0]) {
2077 expr_field_str(field, expr);
2078 return expr;
2079 }
2080
2081 if (field->operator == FIELD_OP_UNARY_MINUS) {
2082 char *subexpr;
2083
2084 strcat(expr, "-(");
2085 subexpr = expr_str(field->operands[0], ++level);
2086 if (!subexpr) {
2087 kfree(expr);
2088 return NULL;
2089 }
2090 strcat(expr, subexpr);
2091 strcat(expr, ")");
2092
2093 kfree(subexpr);
2094
2095 return expr;
2096 }
2097
2098 expr_field_str(field->operands[0], expr);
2099
2100 switch (field->operator) {
2101 case FIELD_OP_MINUS:
2102 strcat(expr, "-");
2103 break;
2104 case FIELD_OP_PLUS:
2105 strcat(expr, "+");
2106 break;
2107 default:
2108 kfree(expr);
2109 return NULL;
2110 }
2111
2112 expr_field_str(field->operands[1], expr);
2113
2114 return expr;
2115 }
2116
2117 static int contains_operator(char *str)
2118 {
2119 enum field_op_id field_op = FIELD_OP_NONE;
2120 char *op;
2121
2122 op = strpbrk(str, "+-");
2123 if (!op)
2124 return FIELD_OP_NONE;
2125
2126 switch (*op) {
2127 case '-':
2128 if (*str == '-')
2129 field_op = FIELD_OP_UNARY_MINUS;
2130 else
2131 field_op = FIELD_OP_MINUS;
2132 break;
2133 case '+':
2134 field_op = FIELD_OP_PLUS;
2135 break;
2136 default:
2137 break;
2138 }
2139
2140 return field_op;
2141 }
2142
2143 static void destroy_hist_field(struct hist_field *hist_field,
2144 unsigned int level)
2145 {
2146 unsigned int i;
2147
2148 if (level > 3)
2149 return;
2150
2151 if (!hist_field)
2152 return;
2153
2154 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++)
2155 destroy_hist_field(hist_field->operands[i], level + 1);
2156
2157 kfree(hist_field->var.name);
2158 kfree(hist_field->name);
2159 kfree(hist_field->type);
2160
2161 kfree(hist_field);
2162 }
2163
2164 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
2165 struct ftrace_event_field *field,
2166 unsigned long flags,
2167 char *var_name)
2168 {
2169 struct hist_field *hist_field;
2170
2171 if (field && is_function_field(field))
2172 return NULL;
2173
2174 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
2175 if (!hist_field)
2176 return NULL;
2177
2178 hist_field->hist_data = hist_data;
2179
2180 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS)
2181 goto out; /* caller will populate */
2182
2183 if (flags & HIST_FIELD_FL_VAR_REF) {
2184 hist_field->fn = hist_field_var_ref;
2185 goto out;
2186 }
2187
2188 if (flags & HIST_FIELD_FL_HITCOUNT) {
2189 hist_field->fn = hist_field_counter;
2190 hist_field->size = sizeof(u64);
2191 hist_field->type = kstrdup("u64", GFP_KERNEL);
2192 if (!hist_field->type)
2193 goto free;
2194 goto out;
2195 }
2196
2197 if (flags & HIST_FIELD_FL_STACKTRACE) {
2198 hist_field->fn = hist_field_none;
2199 goto out;
2200 }
2201
2202 if (flags & HIST_FIELD_FL_LOG2) {
2203 unsigned long fl = flags & ~HIST_FIELD_FL_LOG2;
2204 hist_field->fn = hist_field_log2;
2205 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL);
2206 hist_field->size = hist_field->operands[0]->size;
2207 hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL);
2208 if (!hist_field->type)
2209 goto free;
2210 goto out;
2211 }
2212
2213 if (flags & HIST_FIELD_FL_TIMESTAMP) {
2214 hist_field->fn = hist_field_timestamp;
2215 hist_field->size = sizeof(u64);
2216 hist_field->type = kstrdup("u64", GFP_KERNEL);
2217 if (!hist_field->type)
2218 goto free;
2219 goto out;
2220 }
2221
2222 if (flags & HIST_FIELD_FL_CPU) {
2223 hist_field->fn = hist_field_cpu;
2224 hist_field->size = sizeof(int);
2225 hist_field->type = kstrdup("unsigned int", GFP_KERNEL);
2226 if (!hist_field->type)
2227 goto free;
2228 goto out;
2229 }
2230
2231 if (WARN_ON_ONCE(!field))
2232 goto out;
2233
2234 if (is_string_field(field)) {
2235 flags |= HIST_FIELD_FL_STRING;
2236
2237 hist_field->size = MAX_FILTER_STR_VAL;
2238 hist_field->type = kstrdup(field->type, GFP_KERNEL);
2239 if (!hist_field->type)
2240 goto free;
2241
2242 if (field->filter_type == FILTER_STATIC_STRING)
2243 hist_field->fn = hist_field_string;
2244 else if (field->filter_type == FILTER_DYN_STRING)
2245 hist_field->fn = hist_field_dynstring;
2246 else
2247 hist_field->fn = hist_field_pstring;
2248 } else {
2249 hist_field->size = field->size;
2250 hist_field->is_signed = field->is_signed;
2251 hist_field->type = kstrdup(field->type, GFP_KERNEL);
2252 if (!hist_field->type)
2253 goto free;
2254
2255 hist_field->fn = select_value_fn(field->size,
2256 field->is_signed);
2257 if (!hist_field->fn) {
2258 destroy_hist_field(hist_field, 0);
2259 return NULL;
2260 }
2261 }
2262 out:
2263 hist_field->field = field;
2264 hist_field->flags = flags;
2265
2266 if (var_name) {
2267 hist_field->var.name = kstrdup(var_name, GFP_KERNEL);
2268 if (!hist_field->var.name)
2269 goto free;
2270 }
2271
2272 return hist_field;
2273 free:
2274 destroy_hist_field(hist_field, 0);
2275 return NULL;
2276 }
2277
2278 static void destroy_hist_fields(struct hist_trigger_data *hist_data)
2279 {
2280 unsigned int i;
2281
2282 for (i = 0; i < HIST_FIELDS_MAX; i++) {
2283 if (hist_data->fields[i]) {
2284 destroy_hist_field(hist_data->fields[i], 0);
2285 hist_data->fields[i] = NULL;
2286 }
2287 }
2288 }
2289
2290 static int init_var_ref(struct hist_field *ref_field,
2291 struct hist_field *var_field,
2292 char *system, char *event_name)
2293 {
2294 int err = 0;
2295
2296 ref_field->var.idx = var_field->var.idx;
2297 ref_field->var.hist_data = var_field->hist_data;
2298 ref_field->size = var_field->size;
2299 ref_field->is_signed = var_field->is_signed;
2300 ref_field->flags |= var_field->flags &
2301 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2302
2303 if (system) {
2304 ref_field->system = kstrdup(system, GFP_KERNEL);
2305 if (!ref_field->system)
2306 return -ENOMEM;
2307 }
2308
2309 if (event_name) {
2310 ref_field->event_name = kstrdup(event_name, GFP_KERNEL);
2311 if (!ref_field->event_name) {
2312 err = -ENOMEM;
2313 goto free;
2314 }
2315 }
2316
2317 if (var_field->var.name) {
2318 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL);
2319 if (!ref_field->name) {
2320 err = -ENOMEM;
2321 goto free;
2322 }
2323 } else if (var_field->name) {
2324 ref_field->name = kstrdup(var_field->name, GFP_KERNEL);
2325 if (!ref_field->name) {
2326 err = -ENOMEM;
2327 goto free;
2328 }
2329 }
2330
2331 ref_field->type = kstrdup(var_field->type, GFP_KERNEL);
2332 if (!ref_field->type) {
2333 err = -ENOMEM;
2334 goto free;
2335 }
2336 out:
2337 return err;
2338 free:
2339 kfree(ref_field->system);
2340 kfree(ref_field->event_name);
2341 kfree(ref_field->name);
2342
2343 goto out;
2344 }
2345
2346 static struct hist_field *create_var_ref(struct hist_field *var_field,
2347 char *system, char *event_name)
2348 {
2349 unsigned long flags = HIST_FIELD_FL_VAR_REF;
2350 struct hist_field *ref_field;
2351
2352 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL);
2353 if (ref_field) {
2354 if (init_var_ref(ref_field, var_field, system, event_name)) {
2355 destroy_hist_field(ref_field, 0);
2356 return NULL;
2357 }
2358 }
2359
2360 return ref_field;
2361 }
2362
2363 static bool is_var_ref(char *var_name)
2364 {
2365 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$')
2366 return false;
2367
2368 return true;
2369 }
2370
2371 static char *field_name_from_var(struct hist_trigger_data *hist_data,
2372 char *var_name)
2373 {
2374 char *name, *field;
2375 unsigned int i;
2376
2377 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
2378 name = hist_data->attrs->var_defs.name[i];
2379
2380 if (strcmp(var_name, name) == 0) {
2381 field = hist_data->attrs->var_defs.expr[i];
2382 if (contains_operator(field) || is_var_ref(field))
2383 continue;
2384 return field;
2385 }
2386 }
2387
2388 return NULL;
2389 }
2390
2391 static char *local_field_var_ref(struct hist_trigger_data *hist_data,
2392 char *system, char *event_name,
2393 char *var_name)
2394 {
2395 struct trace_event_call *call;
2396
2397 if (system && event_name) {
2398 call = hist_data->event_file->event_call;
2399
2400 if (strcmp(system, call->class->system) != 0)
2401 return NULL;
2402
2403 if (strcmp(event_name, trace_event_name(call)) != 0)
2404 return NULL;
2405 }
2406
2407 if (!!system != !!event_name)
2408 return NULL;
2409
2410 if (!is_var_ref(var_name))
2411 return NULL;
2412
2413 var_name++;
2414
2415 return field_name_from_var(hist_data, var_name);
2416 }
2417
2418 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data,
2419 char *system, char *event_name,
2420 char *var_name)
2421 {
2422 struct hist_field *var_field = NULL, *ref_field = NULL;
2423
2424 if (!is_var_ref(var_name))
2425 return NULL;
2426
2427 var_name++;
2428
2429 var_field = find_event_var(hist_data, system, event_name, var_name);
2430 if (var_field)
2431 ref_field = create_var_ref(var_field, system, event_name);
2432
2433 if (!ref_field)
2434 hist_err_event("Couldn't find variable: $",
2435 system, event_name, var_name);
2436
2437 return ref_field;
2438 }
2439
2440 static struct ftrace_event_field *
2441 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
2442 char *field_str, unsigned long *flags)
2443 {
2444 struct ftrace_event_field *field = NULL;
2445 char *field_name, *modifier, *str;
2446
2447 modifier = str = kstrdup(field_str, GFP_KERNEL);
2448 if (!modifier)
2449 return ERR_PTR(-ENOMEM);
2450
2451 field_name = strsep(&modifier, ".");
2452 if (modifier) {
2453 if (strcmp(modifier, "hex") == 0)
2454 *flags |= HIST_FIELD_FL_HEX;
2455 else if (strcmp(modifier, "sym") == 0)
2456 *flags |= HIST_FIELD_FL_SYM;
2457 else if (strcmp(modifier, "sym-offset") == 0)
2458 *flags |= HIST_FIELD_FL_SYM_OFFSET;
2459 else if ((strcmp(modifier, "execname") == 0) &&
2460 (strcmp(field_name, "common_pid") == 0))
2461 *flags |= HIST_FIELD_FL_EXECNAME;
2462 else if (strcmp(modifier, "syscall") == 0)
2463 *flags |= HIST_FIELD_FL_SYSCALL;
2464 else if (strcmp(modifier, "log2") == 0)
2465 *flags |= HIST_FIELD_FL_LOG2;
2466 else if (strcmp(modifier, "usecs") == 0)
2467 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS;
2468 else {
2469 field = ERR_PTR(-EINVAL);
2470 goto out;
2471 }
2472 }
2473
2474 if (strcmp(field_name, "common_timestamp") == 0) {
2475 *flags |= HIST_FIELD_FL_TIMESTAMP;
2476 hist_data->enable_timestamps = true;
2477 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS)
2478 hist_data->attrs->ts_in_usecs = true;
2479 } else if (strcmp(field_name, "cpu") == 0)
2480 *flags |= HIST_FIELD_FL_CPU;
2481 else {
2482 field = trace_find_event_field(file->event_call, field_name);
2483 if (!field || !field->size) {
2484 field = ERR_PTR(-EINVAL);
2485 goto out;
2486 }
2487 }
2488 out:
2489 kfree(str);
2490
2491 return field;
2492 }
2493
2494 static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
2495 struct hist_field *var_ref,
2496 char *var_name)
2497 {
2498 struct hist_field *alias = NULL;
2499 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR;
2500
2501 alias = create_hist_field(hist_data, NULL, flags, var_name);
2502 if (!alias)
2503 return NULL;
2504
2505 alias->fn = var_ref->fn;
2506 alias->operands[0] = var_ref;
2507
2508 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) {
2509 destroy_hist_field(alias, 0);
2510 return NULL;
2511 }
2512
2513 return alias;
2514 }
2515
2516 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
2517 struct trace_event_file *file, char *str,
2518 unsigned long *flags, char *var_name)
2519 {
2520 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
2521 struct ftrace_event_field *field = NULL;
2522 struct hist_field *hist_field = NULL;
2523 int ret = 0;
2524
2525 s = strchr(str, '.');
2526 if (s) {
2527 s = strchr(++s, '.');
2528 if (s) {
2529 ref_system = strsep(&str, ".");
2530 if (!str) {
2531 ret = -EINVAL;
2532 goto out;
2533 }
2534 ref_event = strsep(&str, ".");
2535 if (!str) {
2536 ret = -EINVAL;
2537 goto out;
2538 }
2539 ref_var = str;
2540 }
2541 }
2542
2543 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var);
2544 if (!s) {
2545 hist_field = parse_var_ref(hist_data, ref_system, ref_event, ref_var);
2546 if (hist_field) {
2547 hist_data->var_refs[hist_data->n_var_refs] = hist_field;
2548 hist_field->var_ref_idx = hist_data->n_var_refs++;
2549 if (var_name) {
2550 hist_field = create_alias(hist_data, hist_field, var_name);
2551 if (!hist_field) {
2552 ret = -ENOMEM;
2553 goto out;
2554 }
2555 }
2556 return hist_field;
2557 }
2558 } else
2559 str = s;
2560
2561 field = parse_field(hist_data, file, str, flags);
2562 if (IS_ERR(field)) {
2563 ret = PTR_ERR(field);
2564 goto out;
2565 }
2566
2567 hist_field = create_hist_field(hist_data, field, *flags, var_name);
2568 if (!hist_field) {
2569 ret = -ENOMEM;
2570 goto out;
2571 }
2572
2573 return hist_field;
2574 out:
2575 return ERR_PTR(ret);
2576 }
2577
2578 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2579 struct trace_event_file *file,
2580 char *str, unsigned long flags,
2581 char *var_name, unsigned int level);
2582
2583 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
2584 struct trace_event_file *file,
2585 char *str, unsigned long flags,
2586 char *var_name, unsigned int level)
2587 {
2588 struct hist_field *operand1, *expr = NULL;
2589 unsigned long operand_flags;
2590 int ret = 0;
2591 char *s;
2592
2593 /* we support only -(xxx) i.e. explicit parens required */
2594
2595 if (level > 3) {
2596 hist_err("Too many subexpressions (3 max): ", str);
2597 ret = -EINVAL;
2598 goto free;
2599 }
2600
2601 str++; /* skip leading '-' */
2602
2603 s = strchr(str, '(');
2604 if (s)
2605 str++;
2606 else {
2607 ret = -EINVAL;
2608 goto free;
2609 }
2610
2611 s = strrchr(str, ')');
2612 if (s)
2613 *s = '\0';
2614 else {
2615 ret = -EINVAL; /* no closing ')' */
2616 goto free;
2617 }
2618
2619 flags |= HIST_FIELD_FL_EXPR;
2620 expr = create_hist_field(hist_data, NULL, flags, var_name);
2621 if (!expr) {
2622 ret = -ENOMEM;
2623 goto free;
2624 }
2625
2626 operand_flags = 0;
2627 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2628 if (IS_ERR(operand1)) {
2629 ret = PTR_ERR(operand1);
2630 goto free;
2631 }
2632
2633 expr->flags |= operand1->flags &
2634 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2635 expr->fn = hist_field_unary_minus;
2636 expr->operands[0] = operand1;
2637 expr->operator = FIELD_OP_UNARY_MINUS;
2638 expr->name = expr_str(expr, 0);
2639 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2640 if (!expr->type) {
2641 ret = -ENOMEM;
2642 goto free;
2643 }
2644
2645 return expr;
2646 free:
2647 destroy_hist_field(expr, 0);
2648 return ERR_PTR(ret);
2649 }
2650
2651 static int check_expr_operands(struct hist_field *operand1,
2652 struct hist_field *operand2)
2653 {
2654 unsigned long operand1_flags = operand1->flags;
2655 unsigned long operand2_flags = operand2->flags;
2656
2657 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) ||
2658 (operand1_flags & HIST_FIELD_FL_ALIAS)) {
2659 struct hist_field *var;
2660
2661 var = find_var_field(operand1->var.hist_data, operand1->name);
2662 if (!var)
2663 return -EINVAL;
2664 operand1_flags = var->flags;
2665 }
2666
2667 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) ||
2668 (operand2_flags & HIST_FIELD_FL_ALIAS)) {
2669 struct hist_field *var;
2670
2671 var = find_var_field(operand2->var.hist_data, operand2->name);
2672 if (!var)
2673 return -EINVAL;
2674 operand2_flags = var->flags;
2675 }
2676
2677 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) !=
2678 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) {
2679 hist_err("Timestamp units in expression don't match", NULL);
2680 return -EINVAL;
2681 }
2682
2683 return 0;
2684 }
2685
2686 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2687 struct trace_event_file *file,
2688 char *str, unsigned long flags,
2689 char *var_name, unsigned int level)
2690 {
2691 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL;
2692 unsigned long operand_flags;
2693 int field_op, ret = -EINVAL;
2694 char *sep, *operand1_str;
2695
2696 if (level > 3) {
2697 hist_err("Too many subexpressions (3 max): ", str);
2698 return ERR_PTR(-EINVAL);
2699 }
2700
2701 field_op = contains_operator(str);
2702
2703 if (field_op == FIELD_OP_NONE)
2704 return parse_atom(hist_data, file, str, &flags, var_name);
2705
2706 if (field_op == FIELD_OP_UNARY_MINUS)
2707 return parse_unary(hist_data, file, str, flags, var_name, ++level);
2708
2709 switch (field_op) {
2710 case FIELD_OP_MINUS:
2711 sep = "-";
2712 break;
2713 case FIELD_OP_PLUS:
2714 sep = "+";
2715 break;
2716 default:
2717 goto free;
2718 }
2719
2720 operand1_str = strsep(&str, sep);
2721 if (!operand1_str || !str)
2722 goto free;
2723
2724 operand_flags = 0;
2725 operand1 = parse_atom(hist_data, file, operand1_str,
2726 &operand_flags, NULL);
2727 if (IS_ERR(operand1)) {
2728 ret = PTR_ERR(operand1);
2729 operand1 = NULL;
2730 goto free;
2731 }
2732
2733 /* rest of string could be another expression e.g. b+c in a+b+c */
2734 operand_flags = 0;
2735 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2736 if (IS_ERR(operand2)) {
2737 ret = PTR_ERR(operand2);
2738 operand2 = NULL;
2739 goto free;
2740 }
2741
2742 ret = check_expr_operands(operand1, operand2);
2743 if (ret)
2744 goto free;
2745
2746 flags |= HIST_FIELD_FL_EXPR;
2747
2748 flags |= operand1->flags &
2749 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2750
2751 expr = create_hist_field(hist_data, NULL, flags, var_name);
2752 if (!expr) {
2753 ret = -ENOMEM;
2754 goto free;
2755 }
2756
2757 operand1->read_once = true;
2758 operand2->read_once = true;
2759
2760 expr->operands[0] = operand1;
2761 expr->operands[1] = operand2;
2762 expr->operator = field_op;
2763 expr->name = expr_str(expr, 0);
2764 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2765 if (!expr->type) {
2766 ret = -ENOMEM;
2767 goto free;
2768 }
2769
2770 switch (field_op) {
2771 case FIELD_OP_MINUS:
2772 expr->fn = hist_field_minus;
2773 break;
2774 case FIELD_OP_PLUS:
2775 expr->fn = hist_field_plus;
2776 break;
2777 default:
2778 ret = -EINVAL;
2779 goto free;
2780 }
2781
2782 return expr;
2783 free:
2784 destroy_hist_field(operand1, 0);
2785 destroy_hist_field(operand2, 0);
2786 destroy_hist_field(expr, 0);
2787
2788 return ERR_PTR(ret);
2789 }
2790
2791 static char *find_trigger_filter(struct hist_trigger_data *hist_data,
2792 struct trace_event_file *file)
2793 {
2794 struct event_trigger_data *test;
2795
2796 list_for_each_entry_rcu(test, &file->triggers, list) {
2797 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2798 if (test->private_data == hist_data)
2799 return test->filter_str;
2800 }
2801 }
2802
2803 return NULL;
2804 }
2805
2806 static struct event_command trigger_hist_cmd;
2807 static int event_hist_trigger_func(struct event_command *cmd_ops,
2808 struct trace_event_file *file,
2809 char *glob, char *cmd, char *param);
2810
2811 static bool compatible_keys(struct hist_trigger_data *target_hist_data,
2812 struct hist_trigger_data *hist_data,
2813 unsigned int n_keys)
2814 {
2815 struct hist_field *target_hist_field, *hist_field;
2816 unsigned int n, i, j;
2817
2818 if (hist_data->n_fields - hist_data->n_vals != n_keys)
2819 return false;
2820
2821 i = hist_data->n_vals;
2822 j = target_hist_data->n_vals;
2823
2824 for (n = 0; n < n_keys; n++) {
2825 hist_field = hist_data->fields[i + n];
2826 target_hist_field = target_hist_data->fields[j + n];
2827
2828 if (strcmp(hist_field->type, target_hist_field->type) != 0)
2829 return false;
2830 if (hist_field->size != target_hist_field->size)
2831 return false;
2832 if (hist_field->is_signed != target_hist_field->is_signed)
2833 return false;
2834 }
2835
2836 return true;
2837 }
2838
2839 static struct hist_trigger_data *
2840 find_compatible_hist(struct hist_trigger_data *target_hist_data,
2841 struct trace_event_file *file)
2842 {
2843 struct hist_trigger_data *hist_data;
2844 struct event_trigger_data *test;
2845 unsigned int n_keys;
2846
2847 n_keys = target_hist_data->n_fields - target_hist_data->n_vals;
2848
2849 list_for_each_entry_rcu(test, &file->triggers, list) {
2850 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2851 hist_data = test->private_data;
2852
2853 if (compatible_keys(target_hist_data, hist_data, n_keys))
2854 return hist_data;
2855 }
2856 }
2857
2858 return NULL;
2859 }
2860
2861 static struct trace_event_file *event_file(struct trace_array *tr,
2862 char *system, char *event_name)
2863 {
2864 struct trace_event_file *file;
2865
2866 file = find_event_file(tr, system, event_name);
2867 if (!file)
2868 return ERR_PTR(-EINVAL);
2869
2870 return file;
2871 }
2872
2873 static struct hist_field *
2874 find_synthetic_field_var(struct hist_trigger_data *target_hist_data,
2875 char *system, char *event_name, char *field_name)
2876 {
2877 struct hist_field *event_var;
2878 char *synthetic_name;
2879
2880 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2881 if (!synthetic_name)
2882 return ERR_PTR(-ENOMEM);
2883
2884 strcpy(synthetic_name, "synthetic_");
2885 strcat(synthetic_name, field_name);
2886
2887 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name);
2888
2889 kfree(synthetic_name);
2890
2891 return event_var;
2892 }
2893
2894 /**
2895 * create_field_var_hist - Automatically create a histogram and var for a field
2896 * @target_hist_data: The target hist trigger
2897 * @subsys_name: Optional subsystem name
2898 * @event_name: Optional event name
2899 * @field_name: The name of the field (and the resulting variable)
2900 *
2901 * Hist trigger actions fetch data from variables, not directly from
2902 * events. However, for convenience, users are allowed to directly
2903 * specify an event field in an action, which will be automatically
2904 * converted into a variable on their behalf.
2905
2906 * If a user specifies a field on an event that isn't the event the
2907 * histogram currently being defined (the target event histogram), the
2908 * only way that can be accomplished is if a new hist trigger is
2909 * created and the field variable defined on that.
2910 *
2911 * This function creates a new histogram compatible with the target
2912 * event (meaning a histogram with the same key as the target
2913 * histogram), and creates a variable for the specified field, but
2914 * with 'synthetic_' prepended to the variable name in order to avoid
2915 * collision with normal field variables.
2916 *
2917 * Return: The variable created for the field.
2918 */
2919 static struct hist_field *
2920 create_field_var_hist(struct hist_trigger_data *target_hist_data,
2921 char *subsys_name, char *event_name, char *field_name)
2922 {
2923 struct trace_array *tr = target_hist_data->event_file->tr;
2924 struct hist_field *event_var = ERR_PTR(-EINVAL);
2925 struct hist_trigger_data *hist_data;
2926 unsigned int i, n, first = true;
2927 struct field_var_hist *var_hist;
2928 struct trace_event_file *file;
2929 struct hist_field *key_field;
2930 char *saved_filter;
2931 char *cmd;
2932 int ret;
2933
2934 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) {
2935 hist_err_event("onmatch: Too many field variables defined: ",
2936 subsys_name, event_name, field_name);
2937 return ERR_PTR(-EINVAL);
2938 }
2939
2940 file = event_file(tr, subsys_name, event_name);
2941
2942 if (IS_ERR(file)) {
2943 hist_err_event("onmatch: Event file not found: ",
2944 subsys_name, event_name, field_name);
2945 ret = PTR_ERR(file);
2946 return ERR_PTR(ret);
2947 }
2948
2949 /*
2950 * Look for a histogram compatible with target. We'll use the
2951 * found histogram specification to create a new matching
2952 * histogram with our variable on it. target_hist_data is not
2953 * yet a registered histogram so we can't use that.
2954 */
2955 hist_data = find_compatible_hist(target_hist_data, file);
2956 if (!hist_data) {
2957 hist_err_event("onmatch: Matching event histogram not found: ",
2958 subsys_name, event_name, field_name);
2959 return ERR_PTR(-EINVAL);
2960 }
2961
2962 /* See if a synthetic field variable has already been created */
2963 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
2964 event_name, field_name);
2965 if (!IS_ERR_OR_NULL(event_var))
2966 return event_var;
2967
2968 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL);
2969 if (!var_hist)
2970 return ERR_PTR(-ENOMEM);
2971
2972 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2973 if (!cmd) {
2974 kfree(var_hist);
2975 return ERR_PTR(-ENOMEM);
2976 }
2977
2978 /* Use the same keys as the compatible histogram */
2979 strcat(cmd, "keys=");
2980
2981 for_each_hist_key_field(i, hist_data) {
2982 key_field = hist_data->fields[i];
2983 if (!first)
2984 strcat(cmd, ",");
2985 strcat(cmd, key_field->field->name);
2986 first = false;
2987 }
2988
2989 /* Create the synthetic field variable specification */
2990 strcat(cmd, ":synthetic_");
2991 strcat(cmd, field_name);
2992 strcat(cmd, "=");
2993 strcat(cmd, field_name);
2994
2995 /* Use the same filter as the compatible histogram */
2996 saved_filter = find_trigger_filter(hist_data, file);
2997 if (saved_filter) {
2998 strcat(cmd, " if ");
2999 strcat(cmd, saved_filter);
3000 }
3001
3002 var_hist->cmd = kstrdup(cmd, GFP_KERNEL);
3003 if (!var_hist->cmd) {
3004 kfree(cmd);
3005 kfree(var_hist);
3006 return ERR_PTR(-ENOMEM);
3007 }
3008
3009 /* Save the compatible histogram information */
3010 var_hist->hist_data = hist_data;
3011
3012 /* Create the new histogram with our variable */
3013 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
3014 "", "hist", cmd);
3015 if (ret) {
3016 kfree(cmd);
3017 kfree(var_hist->cmd);
3018 kfree(var_hist);
3019 hist_err_event("onmatch: Couldn't create histogram for field: ",
3020 subsys_name, event_name, field_name);
3021 return ERR_PTR(ret);
3022 }
3023
3024 kfree(cmd);
3025
3026 /* If we can't find the variable, something went wrong */
3027 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
3028 event_name, field_name);
3029 if (IS_ERR_OR_NULL(event_var)) {
3030 kfree(var_hist->cmd);
3031 kfree(var_hist);
3032 hist_err_event("onmatch: Couldn't find synthetic variable: ",
3033 subsys_name, event_name, field_name);
3034 return ERR_PTR(-EINVAL);
3035 }
3036
3037 n = target_hist_data->n_field_var_hists;
3038 target_hist_data->field_var_hists[n] = var_hist;
3039 target_hist_data->n_field_var_hists++;
3040
3041 return event_var;
3042 }
3043
3044 static struct hist_field *
3045 find_target_event_var(struct hist_trigger_data *hist_data,
3046 char *subsys_name, char *event_name, char *var_name)
3047 {
3048 struct trace_event_file *file = hist_data->event_file;
3049 struct hist_field *hist_field = NULL;
3050
3051 if (subsys_name) {
3052 struct trace_event_call *call;
3053
3054 if (!event_name)
3055 return NULL;
3056
3057 call = file->event_call;
3058
3059 if (strcmp(subsys_name, call->class->system) != 0)
3060 return NULL;
3061
3062 if (strcmp(event_name, trace_event_name(call)) != 0)
3063 return NULL;
3064 }
3065
3066 hist_field = find_var_field(hist_data, var_name);
3067
3068 return hist_field;
3069 }
3070
3071 static inline void __update_field_vars(struct tracing_map_elt *elt,
3072 struct ring_buffer_event *rbe,
3073 void *rec,
3074 struct field_var **field_vars,
3075 unsigned int n_field_vars,
3076 unsigned int field_var_str_start)
3077 {
3078 struct hist_elt_data *elt_data = elt->private_data;
3079 unsigned int i, j, var_idx;
3080 u64 var_val;
3081
3082 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) {
3083 struct field_var *field_var = field_vars[i];
3084 struct hist_field *var = field_var->var;
3085 struct hist_field *val = field_var->val;
3086
3087 var_val = val->fn(val, elt, rbe, rec);
3088 var_idx = var->var.idx;
3089
3090 if (val->flags & HIST_FIELD_FL_STRING) {
3091 char *str = elt_data->field_var_str[j++];
3092 char *val_str = (char *)(uintptr_t)var_val;
3093
3094 strscpy(str, val_str, STR_VAR_LEN_MAX);
3095 var_val = (u64)(uintptr_t)str;
3096 }
3097 tracing_map_set_var(elt, var_idx, var_val);
3098 }
3099 }
3100
3101 static void update_field_vars(struct hist_trigger_data *hist_data,
3102 struct tracing_map_elt *elt,
3103 struct ring_buffer_event *rbe,
3104 void *rec)
3105 {
3106 __update_field_vars(elt, rbe, rec, hist_data->field_vars,
3107 hist_data->n_field_vars, 0);
3108 }
3109
3110 static void update_max_vars(struct hist_trigger_data *hist_data,
3111 struct tracing_map_elt *elt,
3112 struct ring_buffer_event *rbe,
3113 void *rec)
3114 {
3115 __update_field_vars(elt, rbe, rec, hist_data->max_vars,
3116 hist_data->n_max_vars, hist_data->n_field_var_str);
3117 }
3118
3119 static struct hist_field *create_var(struct hist_trigger_data *hist_data,
3120 struct trace_event_file *file,
3121 char *name, int size, const char *type)
3122 {
3123 struct hist_field *var;
3124 int idx;
3125
3126 if (find_var(hist_data, file, name) && !hist_data->remove) {
3127 var = ERR_PTR(-EINVAL);
3128 goto out;
3129 }
3130
3131 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
3132 if (!var) {
3133 var = ERR_PTR(-ENOMEM);
3134 goto out;
3135 }
3136
3137 idx = tracing_map_add_var(hist_data->map);
3138 if (idx < 0) {
3139 kfree(var);
3140 var = ERR_PTR(-EINVAL);
3141 goto out;
3142 }
3143
3144 var->flags = HIST_FIELD_FL_VAR;
3145 var->var.idx = idx;
3146 var->var.hist_data = var->hist_data = hist_data;
3147 var->size = size;
3148 var->var.name = kstrdup(name, GFP_KERNEL);
3149 var->type = kstrdup(type, GFP_KERNEL);
3150 if (!var->var.name || !var->type) {
3151 kfree(var->var.name);
3152 kfree(var->type);
3153 kfree(var);
3154 var = ERR_PTR(-ENOMEM);
3155 }
3156 out:
3157 return var;
3158 }
3159
3160 static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
3161 struct trace_event_file *file,
3162 char *field_name)
3163 {
3164 struct hist_field *val = NULL, *var = NULL;
3165 unsigned long flags = HIST_FIELD_FL_VAR;
3166 struct field_var *field_var;
3167 int ret = 0;
3168
3169 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) {
3170 hist_err("Too many field variables defined: ", field_name);
3171 ret = -EINVAL;
3172 goto err;
3173 }
3174
3175 val = parse_atom(hist_data, file, field_name, &flags, NULL);
3176 if (IS_ERR(val)) {
3177 hist_err("Couldn't parse field variable: ", field_name);
3178 ret = PTR_ERR(val);
3179 goto err;
3180 }
3181
3182 var = create_var(hist_data, file, field_name, val->size, val->type);
3183 if (IS_ERR(var)) {
3184 hist_err("Couldn't create or find variable: ", field_name);
3185 kfree(val);
3186 ret = PTR_ERR(var);
3187 goto err;
3188 }
3189
3190 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL);
3191 if (!field_var) {
3192 kfree(val);
3193 kfree(var);
3194 ret = -ENOMEM;
3195 goto err;
3196 }
3197
3198 field_var->var = var;
3199 field_var->val = val;
3200 out:
3201 return field_var;
3202 err:
3203 field_var = ERR_PTR(ret);
3204 goto out;
3205 }
3206
3207 /**
3208 * create_target_field_var - Automatically create a variable for a field
3209 * @target_hist_data: The target hist trigger
3210 * @subsys_name: Optional subsystem name
3211 * @event_name: Optional event name
3212 * @var_name: The name of the field (and the resulting variable)
3213 *
3214 * Hist trigger actions fetch data from variables, not directly from
3215 * events. However, for convenience, users are allowed to directly
3216 * specify an event field in an action, which will be automatically
3217 * converted into a variable on their behalf.
3218
3219 * This function creates a field variable with the name var_name on
3220 * the hist trigger currently being defined on the target event. If
3221 * subsys_name and event_name are specified, this function simply
3222 * verifies that they do in fact match the target event subsystem and
3223 * event name.
3224 *
3225 * Return: The variable created for the field.
3226 */
3227 static struct field_var *
3228 create_target_field_var(struct hist_trigger_data *target_hist_data,
3229 char *subsys_name, char *event_name, char *var_name)
3230 {
3231 struct trace_event_file *file = target_hist_data->event_file;
3232
3233 if (subsys_name) {
3234 struct trace_event_call *call;
3235
3236 if (!event_name)
3237 return NULL;
3238
3239 call = file->event_call;
3240
3241 if (strcmp(subsys_name, call->class->system) != 0)
3242 return NULL;
3243
3244 if (strcmp(event_name, trace_event_name(call)) != 0)
3245 return NULL;
3246 }
3247
3248 return create_field_var(target_hist_data, file, var_name);
3249 }
3250
3251 static void onmax_print(struct seq_file *m,
3252 struct hist_trigger_data *hist_data,
3253 struct tracing_map_elt *elt,
3254 struct action_data *data)
3255 {
3256 unsigned int i, save_var_idx, max_idx = data->onmax.max_var->var.idx;
3257
3258 seq_printf(m, "\n\tmax: %10llu", tracing_map_read_var(elt, max_idx));
3259
3260 for (i = 0; i < hist_data->n_max_vars; i++) {
3261 struct hist_field *save_val = hist_data->max_vars[i]->val;
3262 struct hist_field *save_var = hist_data->max_vars[i]->var;
3263 u64 val;
3264
3265 save_var_idx = save_var->var.idx;
3266
3267 val = tracing_map_read_var(elt, save_var_idx);
3268
3269 if (save_val->flags & HIST_FIELD_FL_STRING) {
3270 seq_printf(m, " %s: %-32s", save_var->var.name,
3271 (char *)(uintptr_t)(val));
3272 } else
3273 seq_printf(m, " %s: %10llu", save_var->var.name, val);
3274 }
3275 }
3276
3277 static void onmax_save(struct hist_trigger_data *hist_data,
3278 struct tracing_map_elt *elt, void *rec,
3279 struct ring_buffer_event *rbe,
3280 struct action_data *data, u64 *var_ref_vals)
3281 {
3282 unsigned int max_idx = data->onmax.max_var->var.idx;
3283 unsigned int max_var_ref_idx = data->onmax.max_var_ref_idx;
3284
3285 u64 var_val, max_val;
3286
3287 var_val = var_ref_vals[max_var_ref_idx];
3288 max_val = tracing_map_read_var(elt, max_idx);
3289
3290 if (var_val <= max_val)
3291 return;
3292
3293 tracing_map_set_var(elt, max_idx, var_val);
3294
3295 update_max_vars(hist_data, elt, rbe, rec);
3296 }
3297
3298 static void onmax_destroy(struct action_data *data)
3299 {
3300 unsigned int i;
3301
3302 destroy_hist_field(data->onmax.max_var, 0);
3303 destroy_hist_field(data->onmax.var, 0);
3304
3305 kfree(data->onmax.var_str);
3306 kfree(data->onmax.fn_name);
3307
3308 for (i = 0; i < data->n_params; i++)
3309 kfree(data->params[i]);
3310
3311 kfree(data);
3312 }
3313
3314 static int onmax_create(struct hist_trigger_data *hist_data,
3315 struct action_data *data)
3316 {
3317 struct trace_event_file *file = hist_data->event_file;
3318 struct hist_field *var_field, *ref_field, *max_var;
3319 unsigned int var_ref_idx = hist_data->n_var_refs;
3320 struct field_var *field_var;
3321 char *onmax_var_str, *param;
3322 unsigned long flags;
3323 unsigned int i;
3324 int ret = 0;
3325
3326 onmax_var_str = data->onmax.var_str;
3327 if (onmax_var_str[0] != '$') {
3328 hist_err("onmax: For onmax(x), x must be a variable: ", onmax_var_str);
3329 return -EINVAL;
3330 }
3331 onmax_var_str++;
3332
3333 var_field = find_target_event_var(hist_data, NULL, NULL, onmax_var_str);
3334 if (!var_field) {
3335 hist_err("onmax: Couldn't find onmax variable: ", onmax_var_str);
3336 return -EINVAL;
3337 }
3338
3339 flags = HIST_FIELD_FL_VAR_REF;
3340 ref_field = create_hist_field(hist_data, NULL, flags, NULL);
3341 if (!ref_field)
3342 return -ENOMEM;
3343
3344 if (init_var_ref(ref_field, var_field, NULL, NULL)) {
3345 destroy_hist_field(ref_field, 0);
3346 ret = -ENOMEM;
3347 goto out;
3348 }
3349 hist_data->var_refs[hist_data->n_var_refs] = ref_field;
3350 ref_field->var_ref_idx = hist_data->n_var_refs++;
3351 data->onmax.var = ref_field;
3352
3353 data->fn = onmax_save;
3354 data->onmax.max_var_ref_idx = var_ref_idx;
3355 max_var = create_var(hist_data, file, "max", sizeof(u64), "u64");
3356 if (IS_ERR(max_var)) {
3357 hist_err("onmax: Couldn't create onmax variable: ", "max");
3358 ret = PTR_ERR(max_var);
3359 goto out;
3360 }
3361 data->onmax.max_var = max_var;
3362
3363 for (i = 0; i < data->n_params; i++) {
3364 param = kstrdup(data->params[i], GFP_KERNEL);
3365 if (!param) {
3366 ret = -ENOMEM;
3367 goto out;
3368 }
3369
3370 field_var = create_target_field_var(hist_data, NULL, NULL, param);
3371 if (IS_ERR(field_var)) {
3372 hist_err("onmax: Couldn't create field variable: ", param);
3373 ret = PTR_ERR(field_var);
3374 kfree(param);
3375 goto out;
3376 }
3377
3378 hist_data->max_vars[hist_data->n_max_vars++] = field_var;
3379 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3380 hist_data->n_max_var_str++;
3381
3382 kfree(param);
3383 }
3384 out:
3385 return ret;
3386 }
3387
3388 static int parse_action_params(char *params, struct action_data *data)
3389 {
3390 char *param, *saved_param;
3391 int ret = 0;
3392
3393 while (params) {
3394 if (data->n_params >= SYNTH_FIELDS_MAX)
3395 goto out;
3396
3397 param = strsep(&params, ",");
3398 if (!param) {
3399 ret = -EINVAL;
3400 goto out;
3401 }
3402
3403 param = strstrip(param);
3404 if (strlen(param) < 2) {
3405 hist_err("Invalid action param: ", param);
3406 ret = -EINVAL;
3407 goto out;
3408 }
3409
3410 saved_param = kstrdup(param, GFP_KERNEL);
3411 if (!saved_param) {
3412 ret = -ENOMEM;
3413 goto out;
3414 }
3415
3416 data->params[data->n_params++] = saved_param;
3417 }
3418 out:
3419 return ret;
3420 }
3421
3422 static struct action_data *onmax_parse(char *str)
3423 {
3424 char *onmax_fn_name, *onmax_var_str;
3425 struct action_data *data;
3426 int ret = -EINVAL;
3427
3428 data = kzalloc(sizeof(*data), GFP_KERNEL);
3429 if (!data)
3430 return ERR_PTR(-ENOMEM);
3431
3432 onmax_var_str = strsep(&str, ")");
3433 if (!onmax_var_str || !str) {
3434 ret = -EINVAL;
3435 goto free;
3436 }
3437
3438 data->onmax.var_str = kstrdup(onmax_var_str, GFP_KERNEL);
3439 if (!data->onmax.var_str) {
3440 ret = -ENOMEM;
3441 goto free;
3442 }
3443
3444 strsep(&str, ".");
3445 if (!str)
3446 goto free;
3447
3448 onmax_fn_name = strsep(&str, "(");
3449 if (!onmax_fn_name || !str)
3450 goto free;
3451
3452 if (strncmp(onmax_fn_name, "save", strlen("save")) == 0) {
3453 char *params = strsep(&str, ")");
3454
3455 if (!params) {
3456 ret = -EINVAL;
3457 goto free;
3458 }
3459
3460 ret = parse_action_params(params, data);
3461 if (ret)
3462 goto free;
3463 } else
3464 goto free;
3465
3466 data->onmax.fn_name = kstrdup(onmax_fn_name, GFP_KERNEL);
3467 if (!data->onmax.fn_name) {
3468 ret = -ENOMEM;
3469 goto free;
3470 }
3471 out:
3472 return data;
3473 free:
3474 onmax_destroy(data);
3475 data = ERR_PTR(ret);
3476 goto out;
3477 }
3478
3479 static void onmatch_destroy(struct action_data *data)
3480 {
3481 unsigned int i;
3482
3483 mutex_lock(&synth_event_mutex);
3484
3485 kfree(data->onmatch.match_event);
3486 kfree(data->onmatch.match_event_system);
3487 kfree(data->onmatch.synth_event_name);
3488
3489 for (i = 0; i < data->n_params; i++)
3490 kfree(data->params[i]);
3491
3492 if (data->onmatch.synth_event)
3493 data->onmatch.synth_event->ref--;
3494
3495 kfree(data);
3496
3497 mutex_unlock(&synth_event_mutex);
3498 }
3499
3500 static void destroy_field_var(struct field_var *field_var)
3501 {
3502 if (!field_var)
3503 return;
3504
3505 destroy_hist_field(field_var->var, 0);
3506 destroy_hist_field(field_var->val, 0);
3507
3508 kfree(field_var);
3509 }
3510
3511 static void destroy_field_vars(struct hist_trigger_data *hist_data)
3512 {
3513 unsigned int i;
3514
3515 for (i = 0; i < hist_data->n_field_vars; i++)
3516 destroy_field_var(hist_data->field_vars[i]);
3517 }
3518
3519 static void save_field_var(struct hist_trigger_data *hist_data,
3520 struct field_var *field_var)
3521 {
3522 hist_data->field_vars[hist_data->n_field_vars++] = field_var;
3523
3524 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3525 hist_data->n_field_var_str++;
3526 }
3527
3528
3529 static void destroy_synth_var_refs(struct hist_trigger_data *hist_data)
3530 {
3531 unsigned int i;
3532
3533 for (i = 0; i < hist_data->n_synth_var_refs; i++)
3534 destroy_hist_field(hist_data->synth_var_refs[i], 0);
3535 }
3536
3537 static void save_synth_var_ref(struct hist_trigger_data *hist_data,
3538 struct hist_field *var_ref)
3539 {
3540 hist_data->synth_var_refs[hist_data->n_synth_var_refs++] = var_ref;
3541
3542 hist_data->var_refs[hist_data->n_var_refs] = var_ref;
3543 var_ref->var_ref_idx = hist_data->n_var_refs++;
3544 }
3545
3546 static int check_synth_field(struct synth_event *event,
3547 struct hist_field *hist_field,
3548 unsigned int field_pos)
3549 {
3550 struct synth_field *field;
3551
3552 if (field_pos >= event->n_fields)
3553 return -EINVAL;
3554
3555 field = event->fields[field_pos];
3556
3557 if (strcmp(field->type, hist_field->type) != 0)
3558 return -EINVAL;
3559
3560 return 0;
3561 }
3562
3563 static struct hist_field *
3564 onmatch_find_var(struct hist_trigger_data *hist_data, struct action_data *data,
3565 char *system, char *event, char *var)
3566 {
3567 struct hist_field *hist_field;
3568
3569 var++; /* skip '$' */
3570
3571 hist_field = find_target_event_var(hist_data, system, event, var);
3572 if (!hist_field) {
3573 if (!system) {
3574 system = data->onmatch.match_event_system;
3575 event = data->onmatch.match_event;
3576 }
3577
3578 hist_field = find_event_var(hist_data, system, event, var);
3579 }
3580
3581 if (!hist_field)
3582 hist_err_event("onmatch: Couldn't find onmatch param: $", system, event, var);
3583
3584 return hist_field;
3585 }
3586
3587 static struct hist_field *
3588 onmatch_create_field_var(struct hist_trigger_data *hist_data,
3589 struct action_data *data, char *system,
3590 char *event, char *var)
3591 {
3592 struct hist_field *hist_field = NULL;
3593 struct field_var *field_var;
3594
3595 /*
3596 * First try to create a field var on the target event (the
3597 * currently being defined). This will create a variable for
3598 * unqualified fields on the target event, or if qualified,
3599 * target fields that have qualified names matching the target.
3600 */
3601 field_var = create_target_field_var(hist_data, system, event, var);
3602
3603 if (field_var && !IS_ERR(field_var)) {
3604 save_field_var(hist_data, field_var);
3605 hist_field = field_var->var;
3606 } else {
3607 field_var = NULL;
3608 /*
3609 * If no explicit system.event is specfied, default to
3610 * looking for fields on the onmatch(system.event.xxx)
3611 * event.
3612 */
3613 if (!system) {
3614 system = data->onmatch.match_event_system;
3615 event = data->onmatch.match_event;
3616 }
3617
3618 /*
3619 * At this point, we're looking at a field on another
3620 * event. Because we can't modify a hist trigger on
3621 * another event to add a variable for a field, we need
3622 * to create a new trigger on that event and create the
3623 * variable at the same time.
3624 */
3625 hist_field = create_field_var_hist(hist_data, system, event, var);
3626 if (IS_ERR(hist_field))
3627 goto free;
3628 }
3629 out:
3630 return hist_field;
3631 free:
3632 destroy_field_var(field_var);
3633 hist_field = NULL;
3634 goto out;
3635 }
3636
3637 static int onmatch_create(struct hist_trigger_data *hist_data,
3638 struct trace_event_file *file,
3639 struct action_data *data)
3640 {
3641 char *event_name, *param, *system = NULL;
3642 struct hist_field *hist_field, *var_ref;
3643 unsigned int i, var_ref_idx;
3644 unsigned int field_pos = 0;
3645 struct synth_event *event;
3646 int ret = 0;
3647
3648 mutex_lock(&synth_event_mutex);
3649 event = find_synth_event(data->onmatch.synth_event_name);
3650 if (!event) {
3651 hist_err("onmatch: Couldn't find synthetic event: ", data->onmatch.synth_event_name);
3652 mutex_unlock(&synth_event_mutex);
3653 return -EINVAL;
3654 }
3655 event->ref++;
3656 mutex_unlock(&synth_event_mutex);
3657
3658 var_ref_idx = hist_data->n_var_refs;
3659
3660 for (i = 0; i < data->n_params; i++) {
3661 char *p;
3662
3663 p = param = kstrdup(data->params[i], GFP_KERNEL);
3664 if (!param) {
3665 ret = -ENOMEM;
3666 goto err;
3667 }
3668
3669 system = strsep(&param, ".");
3670 if (!param) {
3671 param = (char *)system;
3672 system = event_name = NULL;
3673 } else {
3674 event_name = strsep(&param, ".");
3675 if (!param) {
3676 kfree(p);
3677 ret = -EINVAL;
3678 goto err;
3679 }
3680 }
3681
3682 if (param[0] == '$')
3683 hist_field = onmatch_find_var(hist_data, data, system,
3684 event_name, param);
3685 else
3686 hist_field = onmatch_create_field_var(hist_data, data,
3687 system,
3688 event_name,
3689 param);
3690
3691 if (!hist_field) {
3692 kfree(p);
3693 ret = -EINVAL;
3694 goto err;
3695 }
3696
3697 if (check_synth_field(event, hist_field, field_pos) == 0) {
3698 var_ref = create_var_ref(hist_field, system, event_name);
3699 if (!var_ref) {
3700 kfree(p);
3701 ret = -ENOMEM;
3702 goto err;
3703 }
3704
3705 save_synth_var_ref(hist_data, var_ref);
3706 field_pos++;
3707 kfree(p);
3708 continue;
3709 }
3710
3711 hist_err_event("onmatch: Param type doesn't match synthetic event field type: ",
3712 system, event_name, param);
3713 kfree(p);
3714 ret = -EINVAL;
3715 goto err;
3716 }
3717
3718 if (field_pos != event->n_fields) {
3719 hist_err("onmatch: Param count doesn't match synthetic event field count: ", event->name);
3720 ret = -EINVAL;
3721 goto err;
3722 }
3723
3724 data->fn = action_trace;
3725 data->onmatch.synth_event = event;
3726 data->onmatch.var_ref_idx = var_ref_idx;
3727 out:
3728 return ret;
3729 err:
3730 mutex_lock(&synth_event_mutex);
3731 event->ref--;
3732 mutex_unlock(&synth_event_mutex);
3733
3734 goto out;
3735 }
3736
3737 static struct action_data *onmatch_parse(struct trace_array *tr, char *str)
3738 {
3739 char *match_event, *match_event_system;
3740 char *synth_event_name, *params;
3741 struct action_data *data;
3742 int ret = -EINVAL;
3743
3744 data = kzalloc(sizeof(*data), GFP_KERNEL);
3745 if (!data)
3746 return ERR_PTR(-ENOMEM);
3747
3748 match_event = strsep(&str, ")");
3749 if (!match_event || !str) {
3750 hist_err("onmatch: Missing closing paren: ", match_event);
3751 goto free;
3752 }
3753
3754 match_event_system = strsep(&match_event, ".");
3755 if (!match_event) {
3756 hist_err("onmatch: Missing subsystem for match event: ", match_event_system);
3757 goto free;
3758 }
3759
3760 if (IS_ERR(event_file(tr, match_event_system, match_event))) {
3761 hist_err_event("onmatch: Invalid subsystem or event name: ",
3762 match_event_system, match_event, NULL);
3763 goto free;
3764 }
3765
3766 data->onmatch.match_event = kstrdup(match_event, GFP_KERNEL);
3767 if (!data->onmatch.match_event) {
3768 ret = -ENOMEM;
3769 goto free;
3770 }
3771
3772 data->onmatch.match_event_system = kstrdup(match_event_system, GFP_KERNEL);
3773 if (!data->onmatch.match_event_system) {
3774 ret = -ENOMEM;
3775 goto free;
3776 }
3777
3778 strsep(&str, ".");
3779 if (!str) {
3780 hist_err("onmatch: Missing . after onmatch(): ", str);
3781 goto free;
3782 }
3783
3784 synth_event_name = strsep(&str, "(");
3785 if (!synth_event_name || !str) {
3786 hist_err("onmatch: Missing opening paramlist paren: ", synth_event_name);
3787 goto free;
3788 }
3789
3790 data->onmatch.synth_event_name = kstrdup(synth_event_name, GFP_KERNEL);
3791 if (!data->onmatch.synth_event_name) {
3792 ret = -ENOMEM;
3793 goto free;
3794 }
3795
3796 params = strsep(&str, ")");
3797 if (!params || !str || (str && strlen(str))) {
3798 hist_err("onmatch: Missing closing paramlist paren: ", params);
3799 goto free;
3800 }
3801
3802 ret = parse_action_params(params, data);
3803 if (ret)
3804 goto free;
3805 out:
3806 return data;
3807 free:
3808 onmatch_destroy(data);
3809 data = ERR_PTR(ret);
3810 goto out;
3811 }
3812
3813 static int create_hitcount_val(struct hist_trigger_data *hist_data)
3814 {
3815 hist_data->fields[HITCOUNT_IDX] =
3816 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL);
3817 if (!hist_data->fields[HITCOUNT_IDX])
3818 return -ENOMEM;
3819
3820 hist_data->n_vals++;
3821 hist_data->n_fields++;
3822
3823 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
3824 return -EINVAL;
3825
3826 return 0;
3827 }
3828
3829 static int __create_val_field(struct hist_trigger_data *hist_data,
3830 unsigned int val_idx,
3831 struct trace_event_file *file,
3832 char *var_name, char *field_str,
3833 unsigned long flags)
3834 {
3835 struct hist_field *hist_field;
3836 int ret = 0;
3837
3838 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0);
3839 if (IS_ERR(hist_field)) {
3840 ret = PTR_ERR(hist_field);
3841 goto out;
3842 }
3843
3844 hist_data->fields[val_idx] = hist_field;
3845
3846 ++hist_data->n_vals;
3847 ++hist_data->n_fields;
3848
3849 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3850 ret = -EINVAL;
3851 out:
3852 return ret;
3853 }
3854
3855 static int create_val_field(struct hist_trigger_data *hist_data,
3856 unsigned int val_idx,
3857 struct trace_event_file *file,
3858 char *field_str)
3859 {
3860 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
3861 return -EINVAL;
3862
3863 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
3864 }
3865
3866 static int create_var_field(struct hist_trigger_data *hist_data,
3867 unsigned int val_idx,
3868 struct trace_event_file *file,
3869 char *var_name, char *expr_str)
3870 {
3871 unsigned long flags = 0;
3872
3873 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3874 return -EINVAL;
3875
3876 if (find_var(hist_data, file, var_name) && !hist_data->remove) {
3877 hist_err("Variable already defined: ", var_name);
3878 return -EINVAL;
3879 }
3880
3881 flags |= HIST_FIELD_FL_VAR;
3882 hist_data->n_vars++;
3883 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX))
3884 return -EINVAL;
3885
3886 return __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags);
3887 }
3888
3889 static int create_val_fields(struct hist_trigger_data *hist_data,
3890 struct trace_event_file *file)
3891 {
3892 char *fields_str, *field_str;
3893 unsigned int i, j = 1;
3894 int ret;
3895
3896 ret = create_hitcount_val(hist_data);
3897 if (ret)
3898 goto out;
3899
3900 fields_str = hist_data->attrs->vals_str;
3901 if (!fields_str)
3902 goto out;
3903
3904 strsep(&fields_str, "=");
3905 if (!fields_str)
3906 goto out;
3907
3908 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
3909 j < TRACING_MAP_VALS_MAX; i++) {
3910 field_str = strsep(&fields_str, ",");
3911 if (!field_str)
3912 break;
3913
3914 if (strcmp(field_str, "hitcount") == 0)
3915 continue;
3916
3917 ret = create_val_field(hist_data, j++, file, field_str);
3918 if (ret)
3919 goto out;
3920 }
3921
3922 if (fields_str && (strcmp(fields_str, "hitcount") != 0))
3923 ret = -EINVAL;
3924 out:
3925 return ret;
3926 }
3927
3928 static int create_key_field(struct hist_trigger_data *hist_data,
3929 unsigned int key_idx,
3930 unsigned int key_offset,
3931 struct trace_event_file *file,
3932 char *field_str)
3933 {
3934 struct hist_field *hist_field = NULL;
3935
3936 unsigned long flags = 0;
3937 unsigned int key_size;
3938 int ret = 0;
3939
3940 if (WARN_ON(key_idx >= HIST_FIELDS_MAX))
3941 return -EINVAL;
3942
3943 flags |= HIST_FIELD_FL_KEY;
3944
3945 if (strcmp(field_str, "stacktrace") == 0) {
3946 flags |= HIST_FIELD_FL_STACKTRACE;
3947 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH;
3948 hist_field = create_hist_field(hist_data, NULL, flags, NULL);
3949 } else {
3950 hist_field = parse_expr(hist_data, file, field_str, flags,
3951 NULL, 0);
3952 if (IS_ERR(hist_field)) {
3953 ret = PTR_ERR(hist_field);
3954 goto out;
3955 }
3956
3957 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) {
3958 hist_err("Using variable references as keys not supported: ", field_str);
3959 destroy_hist_field(hist_field, 0);
3960 ret = -EINVAL;
3961 goto out;
3962 }
3963
3964 key_size = hist_field->size;
3965 }
3966
3967 hist_data->fields[key_idx] = hist_field;
3968
3969 key_size = ALIGN(key_size, sizeof(u64));
3970 hist_data->fields[key_idx]->size = key_size;
3971 hist_data->fields[key_idx]->offset = key_offset;
3972
3973 hist_data->key_size += key_size;
3974
3975 if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
3976 ret = -EINVAL;
3977 goto out;
3978 }
3979
3980 hist_data->n_keys++;
3981 hist_data->n_fields++;
3982
3983 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX))
3984 return -EINVAL;
3985
3986 ret = key_size;
3987 out:
3988 return ret;
3989 }
3990
3991 static int create_key_fields(struct hist_trigger_data *hist_data,
3992 struct trace_event_file *file)
3993 {
3994 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals;
3995 char *fields_str, *field_str;
3996 int ret = -EINVAL;
3997
3998 fields_str = hist_data->attrs->keys_str;
3999 if (!fields_str)
4000 goto out;
4001
4002 strsep(&fields_str, "=");
4003 if (!fields_str)
4004 goto out;
4005
4006 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
4007 field_str = strsep(&fields_str, ",");
4008 if (!field_str)
4009 break;
4010 ret = create_key_field(hist_data, i, key_offset,
4011 file, field_str);
4012 if (ret < 0)
4013 goto out;
4014 key_offset += ret;
4015 }
4016 if (fields_str) {
4017 ret = -EINVAL;
4018 goto out;
4019 }
4020 ret = 0;
4021 out:
4022 return ret;
4023 }
4024
4025 static int create_var_fields(struct hist_trigger_data *hist_data,
4026 struct trace_event_file *file)
4027 {
4028 unsigned int i, j = hist_data->n_vals;
4029 int ret = 0;
4030
4031 unsigned int n_vars = hist_data->attrs->var_defs.n_vars;
4032
4033 for (i = 0; i < n_vars; i++) {
4034 char *var_name = hist_data->attrs->var_defs.name[i];
4035 char *expr = hist_data->attrs->var_defs.expr[i];
4036
4037 ret = create_var_field(hist_data, j++, file, var_name, expr);
4038 if (ret)
4039 goto out;
4040 }
4041 out:
4042 return ret;
4043 }
4044
4045 static void free_var_defs(struct hist_trigger_data *hist_data)
4046 {
4047 unsigned int i;
4048
4049 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
4050 kfree(hist_data->attrs->var_defs.name[i]);
4051 kfree(hist_data->attrs->var_defs.expr[i]);
4052 }
4053
4054 hist_data->attrs->var_defs.n_vars = 0;
4055 }
4056
4057 static int parse_var_defs(struct hist_trigger_data *hist_data)
4058 {
4059 char *s, *str, *var_name, *field_str;
4060 unsigned int i, j, n_vars = 0;
4061 int ret = 0;
4062
4063 for (i = 0; i < hist_data->attrs->n_assignments; i++) {
4064 str = hist_data->attrs->assignment_str[i];
4065 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) {
4066 field_str = strsep(&str, ",");
4067 if (!field_str)
4068 break;
4069
4070 var_name = strsep(&field_str, "=");
4071 if (!var_name || !field_str) {
4072 hist_err("Malformed assignment: ", var_name);
4073 ret = -EINVAL;
4074 goto free;
4075 }
4076
4077 if (n_vars == TRACING_MAP_VARS_MAX) {
4078 hist_err("Too many variables defined: ", var_name);
4079 ret = -EINVAL;
4080 goto free;
4081 }
4082
4083 s = kstrdup(var_name, GFP_KERNEL);
4084 if (!s) {
4085 ret = -ENOMEM;
4086 goto free;
4087 }
4088 hist_data->attrs->var_defs.name[n_vars] = s;
4089
4090 s = kstrdup(field_str, GFP_KERNEL);
4091 if (!s) {
4092 kfree(hist_data->attrs->var_defs.name[n_vars]);
4093 ret = -ENOMEM;
4094 goto free;
4095 }
4096 hist_data->attrs->var_defs.expr[n_vars++] = s;
4097
4098 hist_data->attrs->var_defs.n_vars = n_vars;
4099 }
4100 }
4101
4102 return ret;
4103 free:
4104 free_var_defs(hist_data);
4105
4106 return ret;
4107 }
4108
4109 static int create_hist_fields(struct hist_trigger_data *hist_data,
4110 struct trace_event_file *file)
4111 {
4112 int ret;
4113
4114 ret = parse_var_defs(hist_data);
4115 if (ret)
4116 goto out;
4117
4118 ret = create_val_fields(hist_data, file);
4119 if (ret)
4120 goto out;
4121
4122 ret = create_var_fields(hist_data, file);
4123 if (ret)
4124 goto out;
4125
4126 ret = create_key_fields(hist_data, file);
4127 if (ret)
4128 goto out;
4129 out:
4130 free_var_defs(hist_data);
4131
4132 return ret;
4133 }
4134
4135 static int is_descending(const char *str)
4136 {
4137 if (!str)
4138 return 0;
4139
4140 if (strcmp(str, "descending") == 0)
4141 return 1;
4142
4143 if (strcmp(str, "ascending") == 0)
4144 return 0;
4145
4146 return -EINVAL;
4147 }
4148
4149 static int create_sort_keys(struct hist_trigger_data *hist_data)
4150 {
4151 char *fields_str = hist_data->attrs->sort_key_str;
4152 struct tracing_map_sort_key *sort_key;
4153 int descending, ret = 0;
4154 unsigned int i, j, k;
4155
4156 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
4157
4158 if (!fields_str)
4159 goto out;
4160
4161 strsep(&fields_str, "=");
4162 if (!fields_str) {
4163 ret = -EINVAL;
4164 goto out;
4165 }
4166
4167 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
4168 struct hist_field *hist_field;
4169 char *field_str, *field_name;
4170 const char *test_name;
4171
4172 sort_key = &hist_data->sort_keys[i];
4173
4174 field_str = strsep(&fields_str, ",");
4175 if (!field_str) {
4176 if (i == 0)
4177 ret = -EINVAL;
4178 break;
4179 }
4180
4181 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) {
4182 ret = -EINVAL;
4183 break;
4184 }
4185
4186 field_name = strsep(&field_str, ".");
4187 if (!field_name) {
4188 ret = -EINVAL;
4189 break;
4190 }
4191
4192 if (strcmp(field_name, "hitcount") == 0) {
4193 descending = is_descending(field_str);
4194 if (descending < 0) {
4195 ret = descending;
4196 break;
4197 }
4198 sort_key->descending = descending;
4199 continue;
4200 }
4201
4202 for (j = 1, k = 1; j < hist_data->n_fields; j++) {
4203 unsigned int idx;
4204
4205 hist_field = hist_data->fields[j];
4206 if (hist_field->flags & HIST_FIELD_FL_VAR)
4207 continue;
4208
4209 idx = k++;
4210
4211 test_name = hist_field_name(hist_field, 0);
4212
4213 if (strcmp(field_name, test_name) == 0) {
4214 sort_key->field_idx = idx;
4215 descending = is_descending(field_str);
4216 if (descending < 0) {
4217 ret = descending;
4218 goto out;
4219 }
4220 sort_key->descending = descending;
4221 break;
4222 }
4223 }
4224 if (j == hist_data->n_fields) {
4225 ret = -EINVAL;
4226 break;
4227 }
4228 }
4229
4230 hist_data->n_sort_keys = i;
4231 out:
4232 return ret;
4233 }
4234
4235 static void destroy_actions(struct hist_trigger_data *hist_data)
4236 {
4237 unsigned int i;
4238
4239 for (i = 0; i < hist_data->n_actions; i++) {
4240 struct action_data *data = hist_data->actions[i];
4241
4242 if (data->fn == action_trace)
4243 onmatch_destroy(data);
4244 else if (data->fn == onmax_save)
4245 onmax_destroy(data);
4246 else
4247 kfree(data);
4248 }
4249 }
4250
4251 static int parse_actions(struct hist_trigger_data *hist_data)
4252 {
4253 struct trace_array *tr = hist_data->event_file->tr;
4254 struct action_data *data;
4255 unsigned int i;
4256 int ret = 0;
4257 char *str;
4258
4259 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4260 str = hist_data->attrs->action_str[i];
4261
4262 if (strncmp(str, "onmatch(", strlen("onmatch(")) == 0) {
4263 char *action_str = str + strlen("onmatch(");
4264
4265 data = onmatch_parse(tr, action_str);
4266 if (IS_ERR(data)) {
4267 ret = PTR_ERR(data);
4268 break;
4269 }
4270 data->fn = action_trace;
4271 } else if (strncmp(str, "onmax(", strlen("onmax(")) == 0) {
4272 char *action_str = str + strlen("onmax(");
4273
4274 data = onmax_parse(action_str);
4275 if (IS_ERR(data)) {
4276 ret = PTR_ERR(data);
4277 break;
4278 }
4279 data->fn = onmax_save;
4280 } else {
4281 ret = -EINVAL;
4282 break;
4283 }
4284
4285 hist_data->actions[hist_data->n_actions++] = data;
4286 }
4287
4288 return ret;
4289 }
4290
4291 static int create_actions(struct hist_trigger_data *hist_data,
4292 struct trace_event_file *file)
4293 {
4294 struct action_data *data;
4295 unsigned int i;
4296 int ret = 0;
4297
4298 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4299 data = hist_data->actions[i];
4300
4301 if (data->fn == action_trace) {
4302 ret = onmatch_create(hist_data, file, data);
4303 if (ret)
4304 return ret;
4305 } else if (data->fn == onmax_save) {
4306 ret = onmax_create(hist_data, data);
4307 if (ret)
4308 return ret;
4309 }
4310 }
4311
4312 return ret;
4313 }
4314
4315 static void print_actions(struct seq_file *m,
4316 struct hist_trigger_data *hist_data,
4317 struct tracing_map_elt *elt)
4318 {
4319 unsigned int i;
4320
4321 for (i = 0; i < hist_data->n_actions; i++) {
4322 struct action_data *data = hist_data->actions[i];
4323
4324 if (data->fn == onmax_save)
4325 onmax_print(m, hist_data, elt, data);
4326 }
4327 }
4328
4329 static void print_onmax_spec(struct seq_file *m,
4330 struct hist_trigger_data *hist_data,
4331 struct action_data *data)
4332 {
4333 unsigned int i;
4334
4335 seq_puts(m, ":onmax(");
4336 seq_printf(m, "%s", data->onmax.var_str);
4337 seq_printf(m, ").%s(", data->onmax.fn_name);
4338
4339 for (i = 0; i < hist_data->n_max_vars; i++) {
4340 seq_printf(m, "%s", hist_data->max_vars[i]->var->var.name);
4341 if (i < hist_data->n_max_vars - 1)
4342 seq_puts(m, ",");
4343 }
4344 seq_puts(m, ")");
4345 }
4346
4347 static void print_onmatch_spec(struct seq_file *m,
4348 struct hist_trigger_data *hist_data,
4349 struct action_data *data)
4350 {
4351 unsigned int i;
4352
4353 seq_printf(m, ":onmatch(%s.%s).", data->onmatch.match_event_system,
4354 data->onmatch.match_event);
4355
4356 seq_printf(m, "%s(", data->onmatch.synth_event->name);
4357
4358 for (i = 0; i < data->n_params; i++) {
4359 if (i)
4360 seq_puts(m, ",");
4361 seq_printf(m, "%s", data->params[i]);
4362 }
4363
4364 seq_puts(m, ")");
4365 }
4366
4367 static bool actions_match(struct hist_trigger_data *hist_data,
4368 struct hist_trigger_data *hist_data_test)
4369 {
4370 unsigned int i, j;
4371
4372 if (hist_data->n_actions != hist_data_test->n_actions)
4373 return false;
4374
4375 for (i = 0; i < hist_data->n_actions; i++) {
4376 struct action_data *data = hist_data->actions[i];
4377 struct action_data *data_test = hist_data_test->actions[i];
4378
4379 if (data->fn != data_test->fn)
4380 return false;
4381
4382 if (data->n_params != data_test->n_params)
4383 return false;
4384
4385 for (j = 0; j < data->n_params; j++) {
4386 if (strcmp(data->params[j], data_test->params[j]) != 0)
4387 return false;
4388 }
4389
4390 if (data->fn == action_trace) {
4391 if (strcmp(data->onmatch.synth_event_name,
4392 data_test->onmatch.synth_event_name) != 0)
4393 return false;
4394 if (strcmp(data->onmatch.match_event_system,
4395 data_test->onmatch.match_event_system) != 0)
4396 return false;
4397 if (strcmp(data->onmatch.match_event,
4398 data_test->onmatch.match_event) != 0)
4399 return false;
4400 } else if (data->fn == onmax_save) {
4401 if (strcmp(data->onmax.var_str,
4402 data_test->onmax.var_str) != 0)
4403 return false;
4404 if (strcmp(data->onmax.fn_name,
4405 data_test->onmax.fn_name) != 0)
4406 return false;
4407 }
4408 }
4409
4410 return true;
4411 }
4412
4413
4414 static void print_actions_spec(struct seq_file *m,
4415 struct hist_trigger_data *hist_data)
4416 {
4417 unsigned int i;
4418
4419 for (i = 0; i < hist_data->n_actions; i++) {
4420 struct action_data *data = hist_data->actions[i];
4421
4422 if (data->fn == action_trace)
4423 print_onmatch_spec(m, hist_data, data);
4424 else if (data->fn == onmax_save)
4425 print_onmax_spec(m, hist_data, data);
4426 }
4427 }
4428
4429 static void destroy_field_var_hists(struct hist_trigger_data *hist_data)
4430 {
4431 unsigned int i;
4432
4433 for (i = 0; i < hist_data->n_field_var_hists; i++) {
4434 kfree(hist_data->field_var_hists[i]->cmd);
4435 kfree(hist_data->field_var_hists[i]);
4436 }
4437 }
4438
4439 static void destroy_hist_data(struct hist_trigger_data *hist_data)
4440 {
4441 if (!hist_data)
4442 return;
4443
4444 destroy_hist_trigger_attrs(hist_data->attrs);
4445 destroy_hist_fields(hist_data);
4446 tracing_map_destroy(hist_data->map);
4447
4448 destroy_actions(hist_data);
4449 destroy_field_vars(hist_data);
4450 destroy_field_var_hists(hist_data);
4451 destroy_synth_var_refs(hist_data);
4452
4453 kfree(hist_data);
4454 }
4455
4456 static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
4457 {
4458 struct tracing_map *map = hist_data->map;
4459 struct ftrace_event_field *field;
4460 struct hist_field *hist_field;
4461 int i, idx = 0;
4462
4463 for_each_hist_field(i, hist_data) {
4464 hist_field = hist_data->fields[i];
4465 if (hist_field->flags & HIST_FIELD_FL_KEY) {
4466 tracing_map_cmp_fn_t cmp_fn;
4467
4468 field = hist_field->field;
4469
4470 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
4471 cmp_fn = tracing_map_cmp_none;
4472 else if (!field)
4473 cmp_fn = tracing_map_cmp_num(hist_field->size,
4474 hist_field->is_signed);
4475 else if (is_string_field(field))
4476 cmp_fn = tracing_map_cmp_string;
4477 else
4478 cmp_fn = tracing_map_cmp_num(field->size,
4479 field->is_signed);
4480 idx = tracing_map_add_key_field(map,
4481 hist_field->offset,
4482 cmp_fn);
4483 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR))
4484 idx = tracing_map_add_sum_field(map);
4485
4486 if (idx < 0)
4487 return idx;
4488
4489 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4490 idx = tracing_map_add_var(map);
4491 if (idx < 0)
4492 return idx;
4493 hist_field->var.idx = idx;
4494 hist_field->var.hist_data = hist_data;
4495 }
4496 }
4497
4498 return 0;
4499 }
4500
4501 static struct hist_trigger_data *
4502 create_hist_data(unsigned int map_bits,
4503 struct hist_trigger_attrs *attrs,
4504 struct trace_event_file *file,
4505 bool remove)
4506 {
4507 const struct tracing_map_ops *map_ops = NULL;
4508 struct hist_trigger_data *hist_data;
4509 int ret = 0;
4510
4511 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL);
4512 if (!hist_data)
4513 return ERR_PTR(-ENOMEM);
4514
4515 hist_data->attrs = attrs;
4516 hist_data->remove = remove;
4517 hist_data->event_file = file;
4518
4519 ret = parse_actions(hist_data);
4520 if (ret)
4521 goto free;
4522
4523 ret = create_hist_fields(hist_data, file);
4524 if (ret)
4525 goto free;
4526
4527 ret = create_sort_keys(hist_data);
4528 if (ret)
4529 goto free;
4530
4531 map_ops = &hist_trigger_elt_data_ops;
4532
4533 hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
4534 map_ops, hist_data);
4535 if (IS_ERR(hist_data->map)) {
4536 ret = PTR_ERR(hist_data->map);
4537 hist_data->map = NULL;
4538 goto free;
4539 }
4540
4541 ret = create_tracing_map_fields(hist_data);
4542 if (ret)
4543 goto free;
4544 out:
4545 return hist_data;
4546 free:
4547 hist_data->attrs = NULL;
4548
4549 destroy_hist_data(hist_data);
4550
4551 hist_data = ERR_PTR(ret);
4552
4553 goto out;
4554 }
4555
4556 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
4557 struct tracing_map_elt *elt, void *rec,
4558 struct ring_buffer_event *rbe,
4559 u64 *var_ref_vals)
4560 {
4561 struct hist_elt_data *elt_data;
4562 struct hist_field *hist_field;
4563 unsigned int i, var_idx;
4564 u64 hist_val;
4565
4566 elt_data = elt->private_data;
4567 elt_data->var_ref_vals = var_ref_vals;
4568
4569 for_each_hist_val_field(i, hist_data) {
4570 hist_field = hist_data->fields[i];
4571 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4572 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4573 var_idx = hist_field->var.idx;
4574 tracing_map_set_var(elt, var_idx, hist_val);
4575 continue;
4576 }
4577 tracing_map_update_sum(elt, i, hist_val);
4578 }
4579
4580 for_each_hist_key_field(i, hist_data) {
4581 hist_field = hist_data->fields[i];
4582 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4583 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4584 var_idx = hist_field->var.idx;
4585 tracing_map_set_var(elt, var_idx, hist_val);
4586 }
4587 }
4588
4589 update_field_vars(hist_data, elt, rbe, rec);
4590 }
4591
4592 static inline void add_to_key(char *compound_key, void *key,
4593 struct hist_field *key_field, void *rec)
4594 {
4595 size_t size = key_field->size;
4596
4597 if (key_field->flags & HIST_FIELD_FL_STRING) {
4598 struct ftrace_event_field *field;
4599
4600 field = key_field->field;
4601 if (field->filter_type == FILTER_DYN_STRING)
4602 size = *(u32 *)(rec + field->offset) >> 16;
4603 else if (field->filter_type == FILTER_PTR_STRING)
4604 size = strlen(key);
4605 else if (field->filter_type == FILTER_STATIC_STRING)
4606 size = field->size;
4607
4608 /* ensure NULL-termination */
4609 if (size > key_field->size - 1)
4610 size = key_field->size - 1;
4611 }
4612
4613 memcpy(compound_key + key_field->offset, key, size);
4614 }
4615
4616 static void
4617 hist_trigger_actions(struct hist_trigger_data *hist_data,
4618 struct tracing_map_elt *elt, void *rec,
4619 struct ring_buffer_event *rbe, u64 *var_ref_vals)
4620 {
4621 struct action_data *data;
4622 unsigned int i;
4623
4624 for (i = 0; i < hist_data->n_actions; i++) {
4625 data = hist_data->actions[i];
4626 data->fn(hist_data, elt, rec, rbe, data, var_ref_vals);
4627 }
4628 }
4629
4630 static void event_hist_trigger(struct event_trigger_data *data, void *rec,
4631 struct ring_buffer_event *rbe)
4632 {
4633 struct hist_trigger_data *hist_data = data->private_data;
4634 bool use_compound_key = (hist_data->n_keys > 1);
4635 unsigned long entries[HIST_STACKTRACE_DEPTH];
4636 u64 var_ref_vals[TRACING_MAP_VARS_MAX];
4637 char compound_key[HIST_KEY_SIZE_MAX];
4638 struct tracing_map_elt *elt = NULL;
4639 struct stack_trace stacktrace;
4640 struct hist_field *key_field;
4641 u64 field_contents;
4642 void *key = NULL;
4643 unsigned int i;
4644
4645 memset(compound_key, 0, hist_data->key_size);
4646
4647 for_each_hist_key_field(i, hist_data) {
4648 key_field = hist_data->fields[i];
4649
4650 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4651 stacktrace.max_entries = HIST_STACKTRACE_DEPTH;
4652 stacktrace.entries = entries;
4653 stacktrace.nr_entries = 0;
4654 stacktrace.skip = HIST_STACKTRACE_SKIP;
4655
4656 memset(stacktrace.entries, 0, HIST_STACKTRACE_SIZE);
4657 save_stack_trace(&stacktrace);
4658
4659 key = entries;
4660 } else {
4661 field_contents = key_field->fn(key_field, elt, rbe, rec);
4662 if (key_field->flags & HIST_FIELD_FL_STRING) {
4663 key = (void *)(unsigned long)field_contents;
4664 use_compound_key = true;
4665 } else
4666 key = (void *)&field_contents;
4667 }
4668
4669 if (use_compound_key)
4670 add_to_key(compound_key, key, key_field, rec);
4671 }
4672
4673 if (use_compound_key)
4674 key = compound_key;
4675
4676 if (hist_data->n_var_refs &&
4677 !resolve_var_refs(hist_data, key, var_ref_vals, false))
4678 return;
4679
4680 elt = tracing_map_insert(hist_data->map, key);
4681 if (!elt)
4682 return;
4683
4684 hist_trigger_elt_update(hist_data, elt, rec, rbe, var_ref_vals);
4685
4686 if (resolve_var_refs(hist_data, key, var_ref_vals, true))
4687 hist_trigger_actions(hist_data, elt, rec, rbe, var_ref_vals);
4688 }
4689
4690 static void hist_trigger_stacktrace_print(struct seq_file *m,
4691 unsigned long *stacktrace_entries,
4692 unsigned int max_entries)
4693 {
4694 char str[KSYM_SYMBOL_LEN];
4695 unsigned int spaces = 8;
4696 unsigned int i;
4697
4698 for (i = 0; i < max_entries; i++) {
4699 if (stacktrace_entries[i] == ULONG_MAX)
4700 return;
4701
4702 seq_printf(m, "%*c", 1 + spaces, ' ');
4703 sprint_symbol(str, stacktrace_entries[i]);
4704 seq_printf(m, "%s\n", str);
4705 }
4706 }
4707
4708 static void
4709 hist_trigger_entry_print(struct seq_file *m,
4710 struct hist_trigger_data *hist_data, void *key,
4711 struct tracing_map_elt *elt)
4712 {
4713 struct hist_field *key_field;
4714 char str[KSYM_SYMBOL_LEN];
4715 bool multiline = false;
4716 const char *field_name;
4717 unsigned int i;
4718 u64 uval;
4719
4720 seq_puts(m, "{ ");
4721
4722 for_each_hist_key_field(i, hist_data) {
4723 key_field = hist_data->fields[i];
4724
4725 if (i > hist_data->n_vals)
4726 seq_puts(m, ", ");
4727
4728 field_name = hist_field_name(key_field, 0);
4729
4730 if (key_field->flags & HIST_FIELD_FL_HEX) {
4731 uval = *(u64 *)(key + key_field->offset);
4732 seq_printf(m, "%s: %llx", field_name, uval);
4733 } else if (key_field->flags & HIST_FIELD_FL_SYM) {
4734 uval = *(u64 *)(key + key_field->offset);
4735 sprint_symbol_no_offset(str, uval);
4736 seq_printf(m, "%s: [%llx] %-45s", field_name,
4737 uval, str);
4738 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
4739 uval = *(u64 *)(key + key_field->offset);
4740 sprint_symbol(str, uval);
4741 seq_printf(m, "%s: [%llx] %-55s", field_name,
4742 uval, str);
4743 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
4744 struct hist_elt_data *elt_data = elt->private_data;
4745 char *comm;
4746
4747 if (WARN_ON_ONCE(!elt_data))
4748 return;
4749
4750 comm = elt_data->comm;
4751
4752 uval = *(u64 *)(key + key_field->offset);
4753 seq_printf(m, "%s: %-16s[%10llu]", field_name,
4754 comm, uval);
4755 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
4756 const char *syscall_name;
4757
4758 uval = *(u64 *)(key + key_field->offset);
4759 syscall_name = get_syscall_name(uval);
4760 if (!syscall_name)
4761 syscall_name = "unknown_syscall";
4762
4763 seq_printf(m, "%s: %-30s[%3llu]", field_name,
4764 syscall_name, uval);
4765 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4766 seq_puts(m, "stacktrace:\n");
4767 hist_trigger_stacktrace_print(m,
4768 key + key_field->offset,
4769 HIST_STACKTRACE_DEPTH);
4770 multiline = true;
4771 } else if (key_field->flags & HIST_FIELD_FL_LOG2) {
4772 seq_printf(m, "%s: ~ 2^%-2llu", field_name,
4773 *(u64 *)(key + key_field->offset));
4774 } else if (key_field->flags & HIST_FIELD_FL_STRING) {
4775 seq_printf(m, "%s: %-50s", field_name,
4776 (char *)(key + key_field->offset));
4777 } else {
4778 uval = *(u64 *)(key + key_field->offset);
4779 seq_printf(m, "%s: %10llu", field_name, uval);
4780 }
4781 }
4782
4783 if (!multiline)
4784 seq_puts(m, " ");
4785
4786 seq_puts(m, "}");
4787
4788 seq_printf(m, " hitcount: %10llu",
4789 tracing_map_read_sum(elt, HITCOUNT_IDX));
4790
4791 for (i = 1; i < hist_data->n_vals; i++) {
4792 field_name = hist_field_name(hist_data->fields[i], 0);
4793
4794 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR ||
4795 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR)
4796 continue;
4797
4798 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) {
4799 seq_printf(m, " %s: %10llx", field_name,
4800 tracing_map_read_sum(elt, i));
4801 } else {
4802 seq_printf(m, " %s: %10llu", field_name,
4803 tracing_map_read_sum(elt, i));
4804 }
4805 }
4806
4807 print_actions(m, hist_data, elt);
4808
4809 seq_puts(m, "\n");
4810 }
4811
4812 static int print_entries(struct seq_file *m,
4813 struct hist_trigger_data *hist_data)
4814 {
4815 struct tracing_map_sort_entry **sort_entries = NULL;
4816 struct tracing_map *map = hist_data->map;
4817 int i, n_entries;
4818
4819 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys,
4820 hist_data->n_sort_keys,
4821 &sort_entries);
4822 if (n_entries < 0)
4823 return n_entries;
4824
4825 for (i = 0; i < n_entries; i++)
4826 hist_trigger_entry_print(m, hist_data,
4827 sort_entries[i]->key,
4828 sort_entries[i]->elt);
4829
4830 tracing_map_destroy_sort_entries(sort_entries, n_entries);
4831
4832 return n_entries;
4833 }
4834
4835 static void hist_trigger_show(struct seq_file *m,
4836 struct event_trigger_data *data, int n)
4837 {
4838 struct hist_trigger_data *hist_data;
4839 int n_entries;
4840
4841 if (n > 0)
4842 seq_puts(m, "\n\n");
4843
4844 seq_puts(m, "# event histogram\n#\n# trigger info: ");
4845 data->ops->print(m, data->ops, data);
4846 seq_puts(m, "#\n\n");
4847
4848 hist_data = data->private_data;
4849 n_entries = print_entries(m, hist_data);
4850 if (n_entries < 0)
4851 n_entries = 0;
4852
4853 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
4854 (u64)atomic64_read(&hist_data->map->hits),
4855 n_entries, (u64)atomic64_read(&hist_data->map->drops));
4856 }
4857
4858 static int hist_show(struct seq_file *m, void *v)
4859 {
4860 struct event_trigger_data *data;
4861 struct trace_event_file *event_file;
4862 int n = 0, ret = 0;
4863
4864 mutex_lock(&event_mutex);
4865
4866 event_file = event_file_data(m->private);
4867 if (unlikely(!event_file)) {
4868 ret = -ENODEV;
4869 goto out_unlock;
4870 }
4871
4872 list_for_each_entry_rcu(data, &event_file->triggers, list) {
4873 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
4874 hist_trigger_show(m, data, n++);
4875 }
4876
4877 if (have_hist_err()) {
4878 seq_printf(m, "\nERROR: %s\n", hist_err_str);
4879 seq_printf(m, " Last command: %s\n", last_hist_cmd);
4880 }
4881
4882 out_unlock:
4883 mutex_unlock(&event_mutex);
4884
4885 return ret;
4886 }
4887
4888 static int event_hist_open(struct inode *inode, struct file *file)
4889 {
4890 return single_open(file, hist_show, file);
4891 }
4892
4893 const struct file_operations event_hist_fops = {
4894 .open = event_hist_open,
4895 .read = seq_read,
4896 .llseek = seq_lseek,
4897 .release = single_release,
4898 };
4899
4900 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
4901 {
4902 const char *field_name = hist_field_name(hist_field, 0);
4903
4904 if (hist_field->var.name)
4905 seq_printf(m, "%s=", hist_field->var.name);
4906
4907 if (hist_field->flags & HIST_FIELD_FL_CPU)
4908 seq_puts(m, "cpu");
4909 else if (field_name) {
4910 if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
4911 hist_field->flags & HIST_FIELD_FL_ALIAS)
4912 seq_putc(m, '$');
4913 seq_printf(m, "%s", field_name);
4914 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP)
4915 seq_puts(m, "common_timestamp");
4916 }
4917
4918 static int event_hist_trigger_print(struct seq_file *m,
4919 struct event_trigger_ops *ops,
4920 struct event_trigger_data *data)
4921 {
4922 struct hist_trigger_data *hist_data = data->private_data;
4923 struct hist_field *field;
4924 bool have_var = false;
4925 unsigned int i;
4926
4927 seq_puts(m, "hist:");
4928
4929 if (data->name)
4930 seq_printf(m, "%s:", data->name);
4931
4932 seq_puts(m, "keys=");
4933
4934 for_each_hist_key_field(i, hist_data) {
4935 field = hist_data->fields[i];
4936
4937 if (i > hist_data->n_vals)
4938 seq_puts(m, ",");
4939
4940 if (field->flags & HIST_FIELD_FL_STACKTRACE)
4941 seq_puts(m, "stacktrace");
4942 else
4943 hist_field_print(m, field);
4944 }
4945
4946 seq_puts(m, ":vals=");
4947
4948 for_each_hist_val_field(i, hist_data) {
4949 field = hist_data->fields[i];
4950 if (field->flags & HIST_FIELD_FL_VAR) {
4951 have_var = true;
4952 continue;
4953 }
4954
4955 if (i == HITCOUNT_IDX)
4956 seq_puts(m, "hitcount");
4957 else {
4958 seq_puts(m, ",");
4959 hist_field_print(m, field);
4960 }
4961 }
4962
4963 if (have_var) {
4964 unsigned int n = 0;
4965
4966 seq_puts(m, ":");
4967
4968 for_each_hist_val_field(i, hist_data) {
4969 field = hist_data->fields[i];
4970
4971 if (field->flags & HIST_FIELD_FL_VAR) {
4972 if (n++)
4973 seq_puts(m, ",");
4974 hist_field_print(m, field);
4975 }
4976 }
4977 }
4978
4979 seq_puts(m, ":sort=");
4980
4981 for (i = 0; i < hist_data->n_sort_keys; i++) {
4982 struct tracing_map_sort_key *sort_key;
4983 unsigned int idx, first_key_idx;
4984
4985 /* skip VAR vals */
4986 first_key_idx = hist_data->n_vals - hist_data->n_vars;
4987
4988 sort_key = &hist_data->sort_keys[i];
4989 idx = sort_key->field_idx;
4990
4991 if (WARN_ON(idx >= HIST_FIELDS_MAX))
4992 return -EINVAL;
4993
4994 if (i > 0)
4995 seq_puts(m, ",");
4996
4997 if (idx == HITCOUNT_IDX)
4998 seq_puts(m, "hitcount");
4999 else {
5000 if (idx >= first_key_idx)
5001 idx += hist_data->n_vars;
5002 hist_field_print(m, hist_data->fields[idx]);
5003 }
5004
5005 if (sort_key->descending)
5006 seq_puts(m, ".descending");
5007 }
5008 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
5009 if (hist_data->enable_timestamps)
5010 seq_printf(m, ":clock=%s", hist_data->attrs->clock);
5011
5012 print_actions_spec(m, hist_data);
5013
5014 if (data->filter_str)
5015 seq_printf(m, " if %s", data->filter_str);
5016
5017 if (data->paused)
5018 seq_puts(m, " [paused]");
5019 else
5020 seq_puts(m, " [active]");
5021
5022 seq_putc(m, '\n');
5023
5024 return 0;
5025 }
5026
5027 static int event_hist_trigger_init(struct event_trigger_ops *ops,
5028 struct event_trigger_data *data)
5029 {
5030 struct hist_trigger_data *hist_data = data->private_data;
5031
5032 if (!data->ref && hist_data->attrs->name)
5033 save_named_trigger(hist_data->attrs->name, data);
5034
5035 data->ref++;
5036
5037 return 0;
5038 }
5039
5040 static void unregister_field_var_hists(struct hist_trigger_data *hist_data)
5041 {
5042 struct trace_event_file *file;
5043 unsigned int i;
5044 char *cmd;
5045 int ret;
5046
5047 for (i = 0; i < hist_data->n_field_var_hists; i++) {
5048 file = hist_data->field_var_hists[i]->hist_data->event_file;
5049 cmd = hist_data->field_var_hists[i]->cmd;
5050 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
5051 "!hist", "hist", cmd);
5052 }
5053 }
5054
5055 static void event_hist_trigger_free(struct event_trigger_ops *ops,
5056 struct event_trigger_data *data)
5057 {
5058 struct hist_trigger_data *hist_data = data->private_data;
5059
5060 if (WARN_ON_ONCE(data->ref <= 0))
5061 return;
5062
5063 data->ref--;
5064 if (!data->ref) {
5065 if (data->name)
5066 del_named_trigger(data);
5067
5068 trigger_data_free(data);
5069
5070 remove_hist_vars(hist_data);
5071
5072 unregister_field_var_hists(hist_data);
5073
5074 destroy_hist_data(hist_data);
5075 }
5076 }
5077
5078 static struct event_trigger_ops event_hist_trigger_ops = {
5079 .func = event_hist_trigger,
5080 .print = event_hist_trigger_print,
5081 .init = event_hist_trigger_init,
5082 .free = event_hist_trigger_free,
5083 };
5084
5085 static int event_hist_trigger_named_init(struct event_trigger_ops *ops,
5086 struct event_trigger_data *data)
5087 {
5088 data->ref++;
5089
5090 save_named_trigger(data->named_data->name, data);
5091
5092 event_hist_trigger_init(ops, data->named_data);
5093
5094 return 0;
5095 }
5096
5097 static void event_hist_trigger_named_free(struct event_trigger_ops *ops,
5098 struct event_trigger_data *data)
5099 {
5100 if (WARN_ON_ONCE(data->ref <= 0))
5101 return;
5102
5103 event_hist_trigger_free(ops, data->named_data);
5104
5105 data->ref--;
5106 if (!data->ref) {
5107 del_named_trigger(data);
5108 trigger_data_free(data);
5109 }
5110 }
5111
5112 static struct event_trigger_ops event_hist_trigger_named_ops = {
5113 .func = event_hist_trigger,
5114 .print = event_hist_trigger_print,
5115 .init = event_hist_trigger_named_init,
5116 .free = event_hist_trigger_named_free,
5117 };
5118
5119 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
5120 char *param)
5121 {
5122 return &event_hist_trigger_ops;
5123 }
5124
5125 static void hist_clear(struct event_trigger_data *data)
5126 {
5127 struct hist_trigger_data *hist_data = data->private_data;
5128
5129 if (data->name)
5130 pause_named_trigger(data);
5131
5132 synchronize_sched();
5133
5134 tracing_map_clear(hist_data->map);
5135
5136 if (data->name)
5137 unpause_named_trigger(data);
5138 }
5139
5140 static bool compatible_field(struct ftrace_event_field *field,
5141 struct ftrace_event_field *test_field)
5142 {
5143 if (field == test_field)
5144 return true;
5145 if (field == NULL || test_field == NULL)
5146 return false;
5147 if (strcmp(field->name, test_field->name) != 0)
5148 return false;
5149 if (strcmp(field->type, test_field->type) != 0)
5150 return false;
5151 if (field->size != test_field->size)
5152 return false;
5153 if (field->is_signed != test_field->is_signed)
5154 return false;
5155
5156 return true;
5157 }
5158
5159 static bool hist_trigger_match(struct event_trigger_data *data,
5160 struct event_trigger_data *data_test,
5161 struct event_trigger_data *named_data,
5162 bool ignore_filter)
5163 {
5164 struct tracing_map_sort_key *sort_key, *sort_key_test;
5165 struct hist_trigger_data *hist_data, *hist_data_test;
5166 struct hist_field *key_field, *key_field_test;
5167 unsigned int i;
5168
5169 if (named_data && (named_data != data_test) &&
5170 (named_data != data_test->named_data))
5171 return false;
5172
5173 if (!named_data && is_named_trigger(data_test))
5174 return false;
5175
5176 hist_data = data->private_data;
5177 hist_data_test = data_test->private_data;
5178
5179 if (hist_data->n_vals != hist_data_test->n_vals ||
5180 hist_data->n_fields != hist_data_test->n_fields ||
5181 hist_data->n_sort_keys != hist_data_test->n_sort_keys)
5182 return false;
5183
5184 if (!ignore_filter) {
5185 if ((data->filter_str && !data_test->filter_str) ||
5186 (!data->filter_str && data_test->filter_str))
5187 return false;
5188 }
5189
5190 for_each_hist_field(i, hist_data) {
5191 key_field = hist_data->fields[i];
5192 key_field_test = hist_data_test->fields[i];
5193
5194 if (key_field->flags != key_field_test->flags)
5195 return false;
5196 if (!compatible_field(key_field->field, key_field_test->field))
5197 return false;
5198 if (key_field->offset != key_field_test->offset)
5199 return false;
5200 if (key_field->size != key_field_test->size)
5201 return false;
5202 if (key_field->is_signed != key_field_test->is_signed)
5203 return false;
5204 if (!!key_field->var.name != !!key_field_test->var.name)
5205 return false;
5206 if (key_field->var.name &&
5207 strcmp(key_field->var.name, key_field_test->var.name) != 0)
5208 return false;
5209 }
5210
5211 for (i = 0; i < hist_data->n_sort_keys; i++) {
5212 sort_key = &hist_data->sort_keys[i];
5213 sort_key_test = &hist_data_test->sort_keys[i];
5214
5215 if (sort_key->field_idx != sort_key_test->field_idx ||
5216 sort_key->descending != sort_key_test->descending)
5217 return false;
5218 }
5219
5220 if (!ignore_filter && data->filter_str &&
5221 (strcmp(data->filter_str, data_test->filter_str) != 0))
5222 return false;
5223
5224 if (!actions_match(hist_data, hist_data_test))
5225 return false;
5226
5227 return true;
5228 }
5229
5230 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
5231 struct event_trigger_data *data,
5232 struct trace_event_file *file)
5233 {
5234 struct hist_trigger_data *hist_data = data->private_data;
5235 struct event_trigger_data *test, *named_data = NULL;
5236 int ret = 0;
5237
5238 if (hist_data->attrs->name) {
5239 named_data = find_named_trigger(hist_data->attrs->name);
5240 if (named_data) {
5241 if (!hist_trigger_match(data, named_data, named_data,
5242 true)) {
5243 hist_err("Named hist trigger doesn't match existing named trigger (includes variables): ", hist_data->attrs->name);
5244 ret = -EINVAL;
5245 goto out;
5246 }
5247 }
5248 }
5249
5250 if (hist_data->attrs->name && !named_data)
5251 goto new;
5252
5253 list_for_each_entry_rcu(test, &file->triggers, list) {
5254 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5255 if (!hist_trigger_match(data, test, named_data, false))
5256 continue;
5257 if (hist_data->attrs->pause)
5258 test->paused = true;
5259 else if (hist_data->attrs->cont)
5260 test->paused = false;
5261 else if (hist_data->attrs->clear)
5262 hist_clear(test);
5263 else {
5264 hist_err("Hist trigger already exists", NULL);
5265 ret = -EEXIST;
5266 }
5267 goto out;
5268 }
5269 }
5270 new:
5271 if (hist_data->attrs->cont || hist_data->attrs->clear) {
5272 hist_err("Can't clear or continue a nonexistent hist trigger", NULL);
5273 ret = -ENOENT;
5274 goto out;
5275 }
5276
5277 if (hist_data->attrs->pause)
5278 data->paused = true;
5279
5280 if (named_data) {
5281 data->private_data = named_data->private_data;
5282 set_named_trigger_data(data, named_data);
5283 data->ops = &event_hist_trigger_named_ops;
5284 }
5285
5286 if (data->ops->init) {
5287 ret = data->ops->init(data->ops, data);
5288 if (ret < 0)
5289 goto out;
5290 }
5291
5292 if (hist_data->enable_timestamps) {
5293 char *clock = hist_data->attrs->clock;
5294
5295 ret = tracing_set_clock(file->tr, hist_data->attrs->clock);
5296 if (ret) {
5297 hist_err("Couldn't set trace_clock: ", clock);
5298 goto out;
5299 }
5300
5301 tracing_set_time_stamp_abs(file->tr, true);
5302 }
5303
5304 if (named_data)
5305 destroy_hist_data(hist_data);
5306
5307 ret++;
5308 out:
5309 return ret;
5310 }
5311
5312 static int hist_trigger_enable(struct event_trigger_data *data,
5313 struct trace_event_file *file)
5314 {
5315 int ret = 0;
5316
5317 list_add_tail_rcu(&data->list, &file->triggers);
5318
5319 update_cond_flag(file);
5320
5321 if (trace_event_trigger_enable_disable(file, 1) < 0) {
5322 list_del_rcu(&data->list);
5323 update_cond_flag(file);
5324 ret--;
5325 }
5326
5327 return ret;
5328 }
5329
5330 static bool have_hist_trigger_match(struct event_trigger_data *data,
5331 struct trace_event_file *file)
5332 {
5333 struct hist_trigger_data *hist_data = data->private_data;
5334 struct event_trigger_data *test, *named_data = NULL;
5335 bool match = false;
5336
5337 if (hist_data->attrs->name)
5338 named_data = find_named_trigger(hist_data->attrs->name);
5339
5340 list_for_each_entry_rcu(test, &file->triggers, list) {
5341 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5342 if (hist_trigger_match(data, test, named_data, false)) {
5343 match = true;
5344 break;
5345 }
5346 }
5347 }
5348
5349 return match;
5350 }
5351
5352 static bool hist_trigger_check_refs(struct event_trigger_data *data,
5353 struct trace_event_file *file)
5354 {
5355 struct hist_trigger_data *hist_data = data->private_data;
5356 struct event_trigger_data *test, *named_data = NULL;
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 continue;
5365 hist_data = test->private_data;
5366 if (check_var_refs(hist_data))
5367 return true;
5368 break;
5369 }
5370 }
5371
5372 return false;
5373 }
5374
5375 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops,
5376 struct event_trigger_data *data,
5377 struct trace_event_file *file)
5378 {
5379 struct hist_trigger_data *hist_data = data->private_data;
5380 struct event_trigger_data *test, *named_data = NULL;
5381 bool unregistered = false;
5382
5383 if (hist_data->attrs->name)
5384 named_data = find_named_trigger(hist_data->attrs->name);
5385
5386 list_for_each_entry_rcu(test, &file->triggers, list) {
5387 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5388 if (!hist_trigger_match(data, test, named_data, false))
5389 continue;
5390 unregistered = true;
5391 list_del_rcu(&test->list);
5392 trace_event_trigger_enable_disable(file, 0);
5393 update_cond_flag(file);
5394 break;
5395 }
5396 }
5397
5398 if (unregistered && test->ops->free)
5399 test->ops->free(test->ops, test);
5400
5401 if (hist_data->enable_timestamps) {
5402 if (!hist_data->remove || unregistered)
5403 tracing_set_time_stamp_abs(file->tr, false);
5404 }
5405 }
5406
5407 static bool hist_file_check_refs(struct trace_event_file *file)
5408 {
5409 struct hist_trigger_data *hist_data;
5410 struct event_trigger_data *test;
5411
5412 list_for_each_entry_rcu(test, &file->triggers, list) {
5413 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5414 hist_data = test->private_data;
5415 if (check_var_refs(hist_data))
5416 return true;
5417 }
5418 }
5419
5420 return false;
5421 }
5422
5423 static void hist_unreg_all(struct trace_event_file *file)
5424 {
5425 struct event_trigger_data *test, *n;
5426 struct hist_trigger_data *hist_data;
5427 struct synth_event *se;
5428 const char *se_name;
5429
5430 if (hist_file_check_refs(file))
5431 return;
5432
5433 list_for_each_entry_safe(test, n, &file->triggers, list) {
5434 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5435 hist_data = test->private_data;
5436 list_del_rcu(&test->list);
5437 trace_event_trigger_enable_disable(file, 0);
5438
5439 mutex_lock(&synth_event_mutex);
5440 se_name = trace_event_name(file->event_call);
5441 se = find_synth_event(se_name);
5442 if (se)
5443 se->ref--;
5444 mutex_unlock(&synth_event_mutex);
5445
5446 update_cond_flag(file);
5447 if (hist_data->enable_timestamps)
5448 tracing_set_time_stamp_abs(file->tr, false);
5449 if (test->ops->free)
5450 test->ops->free(test->ops, test);
5451 }
5452 }
5453 }
5454
5455 static int event_hist_trigger_func(struct event_command *cmd_ops,
5456 struct trace_event_file *file,
5457 char *glob, char *cmd, char *param)
5458 {
5459 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
5460 struct event_trigger_data *trigger_data;
5461 struct hist_trigger_attrs *attrs;
5462 struct event_trigger_ops *trigger_ops;
5463 struct hist_trigger_data *hist_data;
5464 struct synth_event *se;
5465 const char *se_name;
5466 bool remove = false;
5467 char *trigger, *p;
5468 int ret = 0;
5469
5470 if (glob && strlen(glob)) {
5471 last_cmd_set(param);
5472 hist_err_clear();
5473 }
5474
5475 if (!param)
5476 return -EINVAL;
5477
5478 if (glob[0] == '!')
5479 remove = true;
5480
5481 /*
5482 * separate the trigger from the filter (k:v [if filter])
5483 * allowing for whitespace in the trigger
5484 */
5485 p = trigger = param;
5486 do {
5487 p = strstr(p, "if");
5488 if (!p)
5489 break;
5490 if (p == param)
5491 return -EINVAL;
5492 if (*(p - 1) != ' ' && *(p - 1) != '\t') {
5493 p++;
5494 continue;
5495 }
5496 if (p >= param + strlen(param) - strlen("if") - 1)
5497 return -EINVAL;
5498 if (*(p + strlen("if")) != ' ' && *(p + strlen("if")) != '\t') {
5499 p++;
5500 continue;
5501 }
5502 break;
5503 } while (p);
5504
5505 if (!p)
5506 param = NULL;
5507 else {
5508 *(p - 1) = '\0';
5509 param = strstrip(p);
5510 trigger = strstrip(trigger);
5511 }
5512
5513 attrs = parse_hist_trigger_attrs(trigger);
5514 if (IS_ERR(attrs))
5515 return PTR_ERR(attrs);
5516
5517 if (attrs->map_bits)
5518 hist_trigger_bits = attrs->map_bits;
5519
5520 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove);
5521 if (IS_ERR(hist_data)) {
5522 destroy_hist_trigger_attrs(attrs);
5523 return PTR_ERR(hist_data);
5524 }
5525
5526 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
5527
5528 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
5529 if (!trigger_data) {
5530 ret = -ENOMEM;
5531 goto out_free;
5532 }
5533
5534 trigger_data->count = -1;
5535 trigger_data->ops = trigger_ops;
5536 trigger_data->cmd_ops = cmd_ops;
5537
5538 INIT_LIST_HEAD(&trigger_data->list);
5539 RCU_INIT_POINTER(trigger_data->filter, NULL);
5540
5541 trigger_data->private_data = hist_data;
5542
5543 /* if param is non-empty, it's supposed to be a filter */
5544 if (param && cmd_ops->set_filter) {
5545 ret = cmd_ops->set_filter(param, trigger_data, file);
5546 if (ret < 0)
5547 goto out_free;
5548 }
5549
5550 if (remove) {
5551 if (!have_hist_trigger_match(trigger_data, file))
5552 goto out_free;
5553
5554 if (hist_trigger_check_refs(trigger_data, file)) {
5555 ret = -EBUSY;
5556 goto out_free;
5557 }
5558
5559 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5560
5561 mutex_lock(&synth_event_mutex);
5562 se_name = trace_event_name(file->event_call);
5563 se = find_synth_event(se_name);
5564 if (se)
5565 se->ref--;
5566 mutex_unlock(&synth_event_mutex);
5567
5568 ret = 0;
5569 goto out_free;
5570 }
5571
5572 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
5573 /*
5574 * The above returns on success the # of triggers registered,
5575 * but if it didn't register any it returns zero. Consider no
5576 * triggers registered a failure too.
5577 */
5578 if (!ret) {
5579 if (!(attrs->pause || attrs->cont || attrs->clear))
5580 ret = -ENOENT;
5581 goto out_free;
5582 } else if (ret < 0)
5583 goto out_free;
5584
5585 if (get_named_trigger_data(trigger_data))
5586 goto enable;
5587
5588 if (has_hist_vars(hist_data))
5589 save_hist_vars(hist_data);
5590
5591 ret = create_actions(hist_data, file);
5592 if (ret)
5593 goto out_unreg;
5594
5595 ret = tracing_map_init(hist_data->map);
5596 if (ret)
5597 goto out_unreg;
5598 enable:
5599 ret = hist_trigger_enable(trigger_data, file);
5600 if (ret)
5601 goto out_unreg;
5602
5603 mutex_lock(&synth_event_mutex);
5604 se_name = trace_event_name(file->event_call);
5605 se = find_synth_event(se_name);
5606 if (se)
5607 se->ref++;
5608 mutex_unlock(&synth_event_mutex);
5609
5610 /* Just return zero, not the number of registered triggers */
5611 ret = 0;
5612 out:
5613 if (ret == 0)
5614 hist_err_clear();
5615
5616 return ret;
5617 out_unreg:
5618 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5619 out_free:
5620 if (cmd_ops->set_filter)
5621 cmd_ops->set_filter(NULL, trigger_data, NULL);
5622
5623 remove_hist_vars(hist_data);
5624
5625 kfree(trigger_data);
5626
5627 destroy_hist_data(hist_data);
5628 goto out;
5629 }
5630
5631 static struct event_command trigger_hist_cmd = {
5632 .name = "hist",
5633 .trigger_type = ETT_EVENT_HIST,
5634 .flags = EVENT_CMD_FL_NEEDS_REC,
5635 .func = event_hist_trigger_func,
5636 .reg = hist_register_trigger,
5637 .unreg = hist_unregister_trigger,
5638 .unreg_all = hist_unreg_all,
5639 .get_trigger_ops = event_hist_get_trigger_ops,
5640 .set_filter = set_trigger_filter,
5641 };
5642
5643 __init int register_trigger_hist_cmd(void)
5644 {
5645 int ret;
5646
5647 ret = register_event_command(&trigger_hist_cmd);
5648 WARN_ON(ret < 0);
5649
5650 return ret;
5651 }
5652
5653 static void
5654 hist_enable_trigger(struct event_trigger_data *data, void *rec,
5655 struct ring_buffer_event *event)
5656 {
5657 struct enable_trigger_data *enable_data = data->private_data;
5658 struct event_trigger_data *test;
5659
5660 list_for_each_entry_rcu(test, &enable_data->file->triggers, list) {
5661 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5662 if (enable_data->enable)
5663 test->paused = false;
5664 else
5665 test->paused = true;
5666 }
5667 }
5668 }
5669
5670 static void
5671 hist_enable_count_trigger(struct event_trigger_data *data, void *rec,
5672 struct ring_buffer_event *event)
5673 {
5674 if (!data->count)
5675 return;
5676
5677 if (data->count != -1)
5678 (data->count)--;
5679
5680 hist_enable_trigger(data, rec, event);
5681 }
5682
5683 static struct event_trigger_ops hist_enable_trigger_ops = {
5684 .func = hist_enable_trigger,
5685 .print = event_enable_trigger_print,
5686 .init = event_trigger_init,
5687 .free = event_enable_trigger_free,
5688 };
5689
5690 static struct event_trigger_ops hist_enable_count_trigger_ops = {
5691 .func = hist_enable_count_trigger,
5692 .print = event_enable_trigger_print,
5693 .init = event_trigger_init,
5694 .free = event_enable_trigger_free,
5695 };
5696
5697 static struct event_trigger_ops hist_disable_trigger_ops = {
5698 .func = hist_enable_trigger,
5699 .print = event_enable_trigger_print,
5700 .init = event_trigger_init,
5701 .free = event_enable_trigger_free,
5702 };
5703
5704 static struct event_trigger_ops hist_disable_count_trigger_ops = {
5705 .func = hist_enable_count_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 *
5712 hist_enable_get_trigger_ops(char *cmd, char *param)
5713 {
5714 struct event_trigger_ops *ops;
5715 bool enable;
5716
5717 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0);
5718
5719 if (enable)
5720 ops = param ? &hist_enable_count_trigger_ops :
5721 &hist_enable_trigger_ops;
5722 else
5723 ops = param ? &hist_disable_count_trigger_ops :
5724 &hist_disable_trigger_ops;
5725
5726 return ops;
5727 }
5728
5729 static void hist_enable_unreg_all(struct trace_event_file *file)
5730 {
5731 struct event_trigger_data *test, *n;
5732
5733 list_for_each_entry_safe(test, n, &file->triggers, list) {
5734 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) {
5735 list_del_rcu(&test->list);
5736 update_cond_flag(file);
5737 trace_event_trigger_enable_disable(file, 0);
5738 if (test->ops->free)
5739 test->ops->free(test->ops, test);
5740 }
5741 }
5742 }
5743
5744 static struct event_command trigger_hist_enable_cmd = {
5745 .name = ENABLE_HIST_STR,
5746 .trigger_type = ETT_HIST_ENABLE,
5747 .func = event_enable_trigger_func,
5748 .reg = event_enable_register_trigger,
5749 .unreg = event_enable_unregister_trigger,
5750 .unreg_all = hist_enable_unreg_all,
5751 .get_trigger_ops = hist_enable_get_trigger_ops,
5752 .set_filter = set_trigger_filter,
5753 };
5754
5755 static struct event_command trigger_hist_disable_cmd = {
5756 .name = DISABLE_HIST_STR,
5757 .trigger_type = ETT_HIST_ENABLE,
5758 .func = event_enable_trigger_func,
5759 .reg = event_enable_register_trigger,
5760 .unreg = event_enable_unregister_trigger,
5761 .unreg_all = hist_enable_unreg_all,
5762 .get_trigger_ops = hist_enable_get_trigger_ops,
5763 .set_filter = set_trigger_filter,
5764 };
5765
5766 static __init void unregister_trigger_hist_enable_disable_cmds(void)
5767 {
5768 unregister_event_command(&trigger_hist_enable_cmd);
5769 unregister_event_command(&trigger_hist_disable_cmd);
5770 }
5771
5772 __init int register_trigger_hist_enable_disable_cmds(void)
5773 {
5774 int ret;
5775
5776 ret = register_event_command(&trigger_hist_enable_cmd);
5777 if (WARN_ON(ret < 0))
5778 return ret;
5779 ret = register_event_command(&trigger_hist_disable_cmd);
5780 if (WARN_ON(ret < 0))
5781 unregister_trigger_hist_enable_disable_cmds();
5782
5783 return ret;
5784 }
5785
5786 static __init int trace_events_hist_init(void)
5787 {
5788 struct dentry *entry = NULL;
5789 struct dentry *d_tracer;
5790 int err = 0;
5791
5792 d_tracer = tracing_init_dentry();
5793 if (IS_ERR(d_tracer)) {
5794 err = PTR_ERR(d_tracer);
5795 goto err;
5796 }
5797
5798 entry = tracefs_create_file("synthetic_events", 0644, d_tracer,
5799 NULL, &synth_events_fops);
5800 if (!entry) {
5801 err = -ENODEV;
5802 goto err;
5803 }
5804
5805 return err;
5806 err:
5807 pr_warn("Could not create tracefs 'synthetic_events' entry\n");
5808
5809 return err;
5810 }
5811
5812 fs_initcall(trace_events_hist_init);
Linux with added FPC-III support