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xfs: add full xfs_dqblk verifier
[linux/fpc-iii.git] / kernel / trace / trace_events_hist.c
blobb9061ed59bbd9faabc7da7a65ae959a89e4b689f
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 hist_err("Invalid field modifier: ", modifier);
2470 field = ERR_PTR(-EINVAL);
2471 goto out;
2472 }
2473 }
2474
2475 if (strcmp(field_name, "common_timestamp") == 0) {
2476 *flags |= HIST_FIELD_FL_TIMESTAMP;
2477 hist_data->enable_timestamps = true;
2478 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS)
2479 hist_data->attrs->ts_in_usecs = true;
2480 } else if (strcmp(field_name, "cpu") == 0)
2481 *flags |= HIST_FIELD_FL_CPU;
2482 else {
2483 field = trace_find_event_field(file->event_call, field_name);
2484 if (!field || !field->size) {
2485 hist_err("Couldn't find field: ", field_name);
2486 field = ERR_PTR(-EINVAL);
2487 goto out;
2488 }
2489 }
2490 out:
2491 kfree(str);
2492
2493 return field;
2494 }
2495
2496 static struct hist_field *create_alias(struct hist_trigger_data *hist_data,
2497 struct hist_field *var_ref,
2498 char *var_name)
2499 {
2500 struct hist_field *alias = NULL;
2501 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR;
2502
2503 alias = create_hist_field(hist_data, NULL, flags, var_name);
2504 if (!alias)
2505 return NULL;
2506
2507 alias->fn = var_ref->fn;
2508 alias->operands[0] = var_ref;
2509
2510 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) {
2511 destroy_hist_field(alias, 0);
2512 return NULL;
2513 }
2514
2515 return alias;
2516 }
2517
2518 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
2519 struct trace_event_file *file, char *str,
2520 unsigned long *flags, char *var_name)
2521 {
2522 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
2523 struct ftrace_event_field *field = NULL;
2524 struct hist_field *hist_field = NULL;
2525 int ret = 0;
2526
2527 s = strchr(str, '.');
2528 if (s) {
2529 s = strchr(++s, '.');
2530 if (s) {
2531 ref_system = strsep(&str, ".");
2532 if (!str) {
2533 ret = -EINVAL;
2534 goto out;
2535 }
2536 ref_event = strsep(&str, ".");
2537 if (!str) {
2538 ret = -EINVAL;
2539 goto out;
2540 }
2541 ref_var = str;
2542 }
2543 }
2544
2545 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var);
2546 if (!s) {
2547 hist_field = parse_var_ref(hist_data, ref_system, ref_event, ref_var);
2548 if (hist_field) {
2549 hist_data->var_refs[hist_data->n_var_refs] = hist_field;
2550 hist_field->var_ref_idx = hist_data->n_var_refs++;
2551 if (var_name) {
2552 hist_field = create_alias(hist_data, hist_field, var_name);
2553 if (!hist_field) {
2554 ret = -ENOMEM;
2555 goto out;
2556 }
2557 }
2558 return hist_field;
2559 }
2560 } else
2561 str = s;
2562
2563 field = parse_field(hist_data, file, str, flags);
2564 if (IS_ERR(field)) {
2565 ret = PTR_ERR(field);
2566 goto out;
2567 }
2568
2569 hist_field = create_hist_field(hist_data, field, *flags, var_name);
2570 if (!hist_field) {
2571 ret = -ENOMEM;
2572 goto out;
2573 }
2574
2575 return hist_field;
2576 out:
2577 return ERR_PTR(ret);
2578 }
2579
2580 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2581 struct trace_event_file *file,
2582 char *str, unsigned long flags,
2583 char *var_name, unsigned int level);
2584
2585 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
2586 struct trace_event_file *file,
2587 char *str, unsigned long flags,
2588 char *var_name, unsigned int level)
2589 {
2590 struct hist_field *operand1, *expr = NULL;
2591 unsigned long operand_flags;
2592 int ret = 0;
2593 char *s;
2594
2595 /* we support only -(xxx) i.e. explicit parens required */
2596
2597 if (level > 3) {
2598 hist_err("Too many subexpressions (3 max): ", str);
2599 ret = -EINVAL;
2600 goto free;
2601 }
2602
2603 str++; /* skip leading '-' */
2604
2605 s = strchr(str, '(');
2606 if (s)
2607 str++;
2608 else {
2609 ret = -EINVAL;
2610 goto free;
2611 }
2612
2613 s = strrchr(str, ')');
2614 if (s)
2615 *s = '\0';
2616 else {
2617 ret = -EINVAL; /* no closing ')' */
2618 goto free;
2619 }
2620
2621 flags |= HIST_FIELD_FL_EXPR;
2622 expr = create_hist_field(hist_data, NULL, flags, var_name);
2623 if (!expr) {
2624 ret = -ENOMEM;
2625 goto free;
2626 }
2627
2628 operand_flags = 0;
2629 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2630 if (IS_ERR(operand1)) {
2631 ret = PTR_ERR(operand1);
2632 goto free;
2633 }
2634
2635 expr->flags |= operand1->flags &
2636 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2637 expr->fn = hist_field_unary_minus;
2638 expr->operands[0] = operand1;
2639 expr->operator = FIELD_OP_UNARY_MINUS;
2640 expr->name = expr_str(expr, 0);
2641 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2642 if (!expr->type) {
2643 ret = -ENOMEM;
2644 goto free;
2645 }
2646
2647 return expr;
2648 free:
2649 destroy_hist_field(expr, 0);
2650 return ERR_PTR(ret);
2651 }
2652
2653 static int check_expr_operands(struct hist_field *operand1,
2654 struct hist_field *operand2)
2655 {
2656 unsigned long operand1_flags = operand1->flags;
2657 unsigned long operand2_flags = operand2->flags;
2658
2659 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) ||
2660 (operand1_flags & HIST_FIELD_FL_ALIAS)) {
2661 struct hist_field *var;
2662
2663 var = find_var_field(operand1->var.hist_data, operand1->name);
2664 if (!var)
2665 return -EINVAL;
2666 operand1_flags = var->flags;
2667 }
2668
2669 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) ||
2670 (operand2_flags & HIST_FIELD_FL_ALIAS)) {
2671 struct hist_field *var;
2672
2673 var = find_var_field(operand2->var.hist_data, operand2->name);
2674 if (!var)
2675 return -EINVAL;
2676 operand2_flags = var->flags;
2677 }
2678
2679 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) !=
2680 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) {
2681 hist_err("Timestamp units in expression don't match", NULL);
2682 return -EINVAL;
2683 }
2684
2685 return 0;
2686 }
2687
2688 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
2689 struct trace_event_file *file,
2690 char *str, unsigned long flags,
2691 char *var_name, unsigned int level)
2692 {
2693 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL;
2694 unsigned long operand_flags;
2695 int field_op, ret = -EINVAL;
2696 char *sep, *operand1_str;
2697
2698 if (level > 3) {
2699 hist_err("Too many subexpressions (3 max): ", str);
2700 return ERR_PTR(-EINVAL);
2701 }
2702
2703 field_op = contains_operator(str);
2704
2705 if (field_op == FIELD_OP_NONE)
2706 return parse_atom(hist_data, file, str, &flags, var_name);
2707
2708 if (field_op == FIELD_OP_UNARY_MINUS)
2709 return parse_unary(hist_data, file, str, flags, var_name, ++level);
2710
2711 switch (field_op) {
2712 case FIELD_OP_MINUS:
2713 sep = "-";
2714 break;
2715 case FIELD_OP_PLUS:
2716 sep = "+";
2717 break;
2718 default:
2719 goto free;
2720 }
2721
2722 operand1_str = strsep(&str, sep);
2723 if (!operand1_str || !str)
2724 goto free;
2725
2726 operand_flags = 0;
2727 operand1 = parse_atom(hist_data, file, operand1_str,
2728 &operand_flags, NULL);
2729 if (IS_ERR(operand1)) {
2730 ret = PTR_ERR(operand1);
2731 operand1 = NULL;
2732 goto free;
2733 }
2734
2735 /* rest of string could be another expression e.g. b+c in a+b+c */
2736 operand_flags = 0;
2737 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level);
2738 if (IS_ERR(operand2)) {
2739 ret = PTR_ERR(operand2);
2740 operand2 = NULL;
2741 goto free;
2742 }
2743
2744 ret = check_expr_operands(operand1, operand2);
2745 if (ret)
2746 goto free;
2747
2748 flags |= HIST_FIELD_FL_EXPR;
2749
2750 flags |= operand1->flags &
2751 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS);
2752
2753 expr = create_hist_field(hist_data, NULL, flags, var_name);
2754 if (!expr) {
2755 ret = -ENOMEM;
2756 goto free;
2757 }
2758
2759 operand1->read_once = true;
2760 operand2->read_once = true;
2761
2762 expr->operands[0] = operand1;
2763 expr->operands[1] = operand2;
2764 expr->operator = field_op;
2765 expr->name = expr_str(expr, 0);
2766 expr->type = kstrdup(operand1->type, GFP_KERNEL);
2767 if (!expr->type) {
2768 ret = -ENOMEM;
2769 goto free;
2770 }
2771
2772 switch (field_op) {
2773 case FIELD_OP_MINUS:
2774 expr->fn = hist_field_minus;
2775 break;
2776 case FIELD_OP_PLUS:
2777 expr->fn = hist_field_plus;
2778 break;
2779 default:
2780 ret = -EINVAL;
2781 goto free;
2782 }
2783
2784 return expr;
2785 free:
2786 destroy_hist_field(operand1, 0);
2787 destroy_hist_field(operand2, 0);
2788 destroy_hist_field(expr, 0);
2789
2790 return ERR_PTR(ret);
2791 }
2792
2793 static char *find_trigger_filter(struct hist_trigger_data *hist_data,
2794 struct trace_event_file *file)
2795 {
2796 struct event_trigger_data *test;
2797
2798 list_for_each_entry_rcu(test, &file->triggers, list) {
2799 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2800 if (test->private_data == hist_data)
2801 return test->filter_str;
2802 }
2803 }
2804
2805 return NULL;
2806 }
2807
2808 static struct event_command trigger_hist_cmd;
2809 static int event_hist_trigger_func(struct event_command *cmd_ops,
2810 struct trace_event_file *file,
2811 char *glob, char *cmd, char *param);
2812
2813 static bool compatible_keys(struct hist_trigger_data *target_hist_data,
2814 struct hist_trigger_data *hist_data,
2815 unsigned int n_keys)
2816 {
2817 struct hist_field *target_hist_field, *hist_field;
2818 unsigned int n, i, j;
2819
2820 if (hist_data->n_fields - hist_data->n_vals != n_keys)
2821 return false;
2822
2823 i = hist_data->n_vals;
2824 j = target_hist_data->n_vals;
2825
2826 for (n = 0; n < n_keys; n++) {
2827 hist_field = hist_data->fields[i + n];
2828 target_hist_field = target_hist_data->fields[j + n];
2829
2830 if (strcmp(hist_field->type, target_hist_field->type) != 0)
2831 return false;
2832 if (hist_field->size != target_hist_field->size)
2833 return false;
2834 if (hist_field->is_signed != target_hist_field->is_signed)
2835 return false;
2836 }
2837
2838 return true;
2839 }
2840
2841 static struct hist_trigger_data *
2842 find_compatible_hist(struct hist_trigger_data *target_hist_data,
2843 struct trace_event_file *file)
2844 {
2845 struct hist_trigger_data *hist_data;
2846 struct event_trigger_data *test;
2847 unsigned int n_keys;
2848
2849 n_keys = target_hist_data->n_fields - target_hist_data->n_vals;
2850
2851 list_for_each_entry_rcu(test, &file->triggers, list) {
2852 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
2853 hist_data = test->private_data;
2854
2855 if (compatible_keys(target_hist_data, hist_data, n_keys))
2856 return hist_data;
2857 }
2858 }
2859
2860 return NULL;
2861 }
2862
2863 static struct trace_event_file *event_file(struct trace_array *tr,
2864 char *system, char *event_name)
2865 {
2866 struct trace_event_file *file;
2867
2868 file = find_event_file(tr, system, event_name);
2869 if (!file)
2870 return ERR_PTR(-EINVAL);
2871
2872 return file;
2873 }
2874
2875 static struct hist_field *
2876 find_synthetic_field_var(struct hist_trigger_data *target_hist_data,
2877 char *system, char *event_name, char *field_name)
2878 {
2879 struct hist_field *event_var;
2880 char *synthetic_name;
2881
2882 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2883 if (!synthetic_name)
2884 return ERR_PTR(-ENOMEM);
2885
2886 strcpy(synthetic_name, "synthetic_");
2887 strcat(synthetic_name, field_name);
2888
2889 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name);
2890
2891 kfree(synthetic_name);
2892
2893 return event_var;
2894 }
2895
2896 /**
2897 * create_field_var_hist - Automatically create a histogram and var for a field
2898 * @target_hist_data: The target hist trigger
2899 * @subsys_name: Optional subsystem name
2900 * @event_name: Optional event name
2901 * @field_name: The name of the field (and the resulting variable)
2902 *
2903 * Hist trigger actions fetch data from variables, not directly from
2904 * events. However, for convenience, users are allowed to directly
2905 * specify an event field in an action, which will be automatically
2906 * converted into a variable on their behalf.
2907
2908 * If a user specifies a field on an event that isn't the event the
2909 * histogram currently being defined (the target event histogram), the
2910 * only way that can be accomplished is if a new hist trigger is
2911 * created and the field variable defined on that.
2912 *
2913 * This function creates a new histogram compatible with the target
2914 * event (meaning a histogram with the same key as the target
2915 * histogram), and creates a variable for the specified field, but
2916 * with 'synthetic_' prepended to the variable name in order to avoid
2917 * collision with normal field variables.
2918 *
2919 * Return: The variable created for the field.
2920 */
2921 static struct hist_field *
2922 create_field_var_hist(struct hist_trigger_data *target_hist_data,
2923 char *subsys_name, char *event_name, char *field_name)
2924 {
2925 struct trace_array *tr = target_hist_data->event_file->tr;
2926 struct hist_field *event_var = ERR_PTR(-EINVAL);
2927 struct hist_trigger_data *hist_data;
2928 unsigned int i, n, first = true;
2929 struct field_var_hist *var_hist;
2930 struct trace_event_file *file;
2931 struct hist_field *key_field;
2932 char *saved_filter;
2933 char *cmd;
2934 int ret;
2935
2936 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) {
2937 hist_err_event("onmatch: Too many field variables defined: ",
2938 subsys_name, event_name, field_name);
2939 return ERR_PTR(-EINVAL);
2940 }
2941
2942 file = event_file(tr, subsys_name, event_name);
2943
2944 if (IS_ERR(file)) {
2945 hist_err_event("onmatch: Event file not found: ",
2946 subsys_name, event_name, field_name);
2947 ret = PTR_ERR(file);
2948 return ERR_PTR(ret);
2949 }
2950
2951 /*
2952 * Look for a histogram compatible with target. We'll use the
2953 * found histogram specification to create a new matching
2954 * histogram with our variable on it. target_hist_data is not
2955 * yet a registered histogram so we can't use that.
2956 */
2957 hist_data = find_compatible_hist(target_hist_data, file);
2958 if (!hist_data) {
2959 hist_err_event("onmatch: Matching event histogram not found: ",
2960 subsys_name, event_name, field_name);
2961 return ERR_PTR(-EINVAL);
2962 }
2963
2964 /* See if a synthetic field variable has already been created */
2965 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
2966 event_name, field_name);
2967 if (!IS_ERR_OR_NULL(event_var))
2968 return event_var;
2969
2970 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL);
2971 if (!var_hist)
2972 return ERR_PTR(-ENOMEM);
2973
2974 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL);
2975 if (!cmd) {
2976 kfree(var_hist);
2977 return ERR_PTR(-ENOMEM);
2978 }
2979
2980 /* Use the same keys as the compatible histogram */
2981 strcat(cmd, "keys=");
2982
2983 for_each_hist_key_field(i, hist_data) {
2984 key_field = hist_data->fields[i];
2985 if (!first)
2986 strcat(cmd, ",");
2987 strcat(cmd, key_field->field->name);
2988 first = false;
2989 }
2990
2991 /* Create the synthetic field variable specification */
2992 strcat(cmd, ":synthetic_");
2993 strcat(cmd, field_name);
2994 strcat(cmd, "=");
2995 strcat(cmd, field_name);
2996
2997 /* Use the same filter as the compatible histogram */
2998 saved_filter = find_trigger_filter(hist_data, file);
2999 if (saved_filter) {
3000 strcat(cmd, " if ");
3001 strcat(cmd, saved_filter);
3002 }
3003
3004 var_hist->cmd = kstrdup(cmd, GFP_KERNEL);
3005 if (!var_hist->cmd) {
3006 kfree(cmd);
3007 kfree(var_hist);
3008 return ERR_PTR(-ENOMEM);
3009 }
3010
3011 /* Save the compatible histogram information */
3012 var_hist->hist_data = hist_data;
3013
3014 /* Create the new histogram with our variable */
3015 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
3016 "", "hist", cmd);
3017 if (ret) {
3018 kfree(cmd);
3019 kfree(var_hist->cmd);
3020 kfree(var_hist);
3021 hist_err_event("onmatch: Couldn't create histogram for field: ",
3022 subsys_name, event_name, field_name);
3023 return ERR_PTR(ret);
3024 }
3025
3026 kfree(cmd);
3027
3028 /* If we can't find the variable, something went wrong */
3029 event_var = find_synthetic_field_var(target_hist_data, subsys_name,
3030 event_name, field_name);
3031 if (IS_ERR_OR_NULL(event_var)) {
3032 kfree(var_hist->cmd);
3033 kfree(var_hist);
3034 hist_err_event("onmatch: Couldn't find synthetic variable: ",
3035 subsys_name, event_name, field_name);
3036 return ERR_PTR(-EINVAL);
3037 }
3038
3039 n = target_hist_data->n_field_var_hists;
3040 target_hist_data->field_var_hists[n] = var_hist;
3041 target_hist_data->n_field_var_hists++;
3042
3043 return event_var;
3044 }
3045
3046 static struct hist_field *
3047 find_target_event_var(struct hist_trigger_data *hist_data,
3048 char *subsys_name, char *event_name, char *var_name)
3049 {
3050 struct trace_event_file *file = hist_data->event_file;
3051 struct hist_field *hist_field = NULL;
3052
3053 if (subsys_name) {
3054 struct trace_event_call *call;
3055
3056 if (!event_name)
3057 return NULL;
3058
3059 call = file->event_call;
3060
3061 if (strcmp(subsys_name, call->class->system) != 0)
3062 return NULL;
3063
3064 if (strcmp(event_name, trace_event_name(call)) != 0)
3065 return NULL;
3066 }
3067
3068 hist_field = find_var_field(hist_data, var_name);
3069
3070 return hist_field;
3071 }
3072
3073 static inline void __update_field_vars(struct tracing_map_elt *elt,
3074 struct ring_buffer_event *rbe,
3075 void *rec,
3076 struct field_var **field_vars,
3077 unsigned int n_field_vars,
3078 unsigned int field_var_str_start)
3079 {
3080 struct hist_elt_data *elt_data = elt->private_data;
3081 unsigned int i, j, var_idx;
3082 u64 var_val;
3083
3084 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) {
3085 struct field_var *field_var = field_vars[i];
3086 struct hist_field *var = field_var->var;
3087 struct hist_field *val = field_var->val;
3088
3089 var_val = val->fn(val, elt, rbe, rec);
3090 var_idx = var->var.idx;
3091
3092 if (val->flags & HIST_FIELD_FL_STRING) {
3093 char *str = elt_data->field_var_str[j++];
3094 char *val_str = (char *)(uintptr_t)var_val;
3095
3096 strscpy(str, val_str, STR_VAR_LEN_MAX);
3097 var_val = (u64)(uintptr_t)str;
3098 }
3099 tracing_map_set_var(elt, var_idx, var_val);
3100 }
3101 }
3102
3103 static void update_field_vars(struct hist_trigger_data *hist_data,
3104 struct tracing_map_elt *elt,
3105 struct ring_buffer_event *rbe,
3106 void *rec)
3107 {
3108 __update_field_vars(elt, rbe, rec, hist_data->field_vars,
3109 hist_data->n_field_vars, 0);
3110 }
3111
3112 static void update_max_vars(struct hist_trigger_data *hist_data,
3113 struct tracing_map_elt *elt,
3114 struct ring_buffer_event *rbe,
3115 void *rec)
3116 {
3117 __update_field_vars(elt, rbe, rec, hist_data->max_vars,
3118 hist_data->n_max_vars, hist_data->n_field_var_str);
3119 }
3120
3121 static struct hist_field *create_var(struct hist_trigger_data *hist_data,
3122 struct trace_event_file *file,
3123 char *name, int size, const char *type)
3124 {
3125 struct hist_field *var;
3126 int idx;
3127
3128 if (find_var(hist_data, file, name) && !hist_data->remove) {
3129 var = ERR_PTR(-EINVAL);
3130 goto out;
3131 }
3132
3133 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL);
3134 if (!var) {
3135 var = ERR_PTR(-ENOMEM);
3136 goto out;
3137 }
3138
3139 idx = tracing_map_add_var(hist_data->map);
3140 if (idx < 0) {
3141 kfree(var);
3142 var = ERR_PTR(-EINVAL);
3143 goto out;
3144 }
3145
3146 var->flags = HIST_FIELD_FL_VAR;
3147 var->var.idx = idx;
3148 var->var.hist_data = var->hist_data = hist_data;
3149 var->size = size;
3150 var->var.name = kstrdup(name, GFP_KERNEL);
3151 var->type = kstrdup(type, GFP_KERNEL);
3152 if (!var->var.name || !var->type) {
3153 kfree(var->var.name);
3154 kfree(var->type);
3155 kfree(var);
3156 var = ERR_PTR(-ENOMEM);
3157 }
3158 out:
3159 return var;
3160 }
3161
3162 static struct field_var *create_field_var(struct hist_trigger_data *hist_data,
3163 struct trace_event_file *file,
3164 char *field_name)
3165 {
3166 struct hist_field *val = NULL, *var = NULL;
3167 unsigned long flags = HIST_FIELD_FL_VAR;
3168 struct field_var *field_var;
3169 int ret = 0;
3170
3171 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) {
3172 hist_err("Too many field variables defined: ", field_name);
3173 ret = -EINVAL;
3174 goto err;
3175 }
3176
3177 val = parse_atom(hist_data, file, field_name, &flags, NULL);
3178 if (IS_ERR(val)) {
3179 hist_err("Couldn't parse field variable: ", field_name);
3180 ret = PTR_ERR(val);
3181 goto err;
3182 }
3183
3184 var = create_var(hist_data, file, field_name, val->size, val->type);
3185 if (IS_ERR(var)) {
3186 hist_err("Couldn't create or find variable: ", field_name);
3187 kfree(val);
3188 ret = PTR_ERR(var);
3189 goto err;
3190 }
3191
3192 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL);
3193 if (!field_var) {
3194 kfree(val);
3195 kfree(var);
3196 ret = -ENOMEM;
3197 goto err;
3198 }
3199
3200 field_var->var = var;
3201 field_var->val = val;
3202 out:
3203 return field_var;
3204 err:
3205 field_var = ERR_PTR(ret);
3206 goto out;
3207 }
3208
3209 /**
3210 * create_target_field_var - Automatically create a variable for a field
3211 * @target_hist_data: The target hist trigger
3212 * @subsys_name: Optional subsystem name
3213 * @event_name: Optional event name
3214 * @var_name: The name of the field (and the resulting variable)
3215 *
3216 * Hist trigger actions fetch data from variables, not directly from
3217 * events. However, for convenience, users are allowed to directly
3218 * specify an event field in an action, which will be automatically
3219 * converted into a variable on their behalf.
3220
3221 * This function creates a field variable with the name var_name on
3222 * the hist trigger currently being defined on the target event. If
3223 * subsys_name and event_name are specified, this function simply
3224 * verifies that they do in fact match the target event subsystem and
3225 * event name.
3226 *
3227 * Return: The variable created for the field.
3228 */
3229 static struct field_var *
3230 create_target_field_var(struct hist_trigger_data *target_hist_data,
3231 char *subsys_name, char *event_name, char *var_name)
3232 {
3233 struct trace_event_file *file = target_hist_data->event_file;
3234
3235 if (subsys_name) {
3236 struct trace_event_call *call;
3237
3238 if (!event_name)
3239 return NULL;
3240
3241 call = file->event_call;
3242
3243 if (strcmp(subsys_name, call->class->system) != 0)
3244 return NULL;
3245
3246 if (strcmp(event_name, trace_event_name(call)) != 0)
3247 return NULL;
3248 }
3249
3250 return create_field_var(target_hist_data, file, var_name);
3251 }
3252
3253 static void onmax_print(struct seq_file *m,
3254 struct hist_trigger_data *hist_data,
3255 struct tracing_map_elt *elt,
3256 struct action_data *data)
3257 {
3258 unsigned int i, save_var_idx, max_idx = data->onmax.max_var->var.idx;
3259
3260 seq_printf(m, "\n\tmax: %10llu", tracing_map_read_var(elt, max_idx));
3261
3262 for (i = 0; i < hist_data->n_max_vars; i++) {
3263 struct hist_field *save_val = hist_data->max_vars[i]->val;
3264 struct hist_field *save_var = hist_data->max_vars[i]->var;
3265 u64 val;
3266
3267 save_var_idx = save_var->var.idx;
3268
3269 val = tracing_map_read_var(elt, save_var_idx);
3270
3271 if (save_val->flags & HIST_FIELD_FL_STRING) {
3272 seq_printf(m, " %s: %-32s", save_var->var.name,
3273 (char *)(uintptr_t)(val));
3274 } else
3275 seq_printf(m, " %s: %10llu", save_var->var.name, val);
3276 }
3277 }
3278
3279 static void onmax_save(struct hist_trigger_data *hist_data,
3280 struct tracing_map_elt *elt, void *rec,
3281 struct ring_buffer_event *rbe,
3282 struct action_data *data, u64 *var_ref_vals)
3283 {
3284 unsigned int max_idx = data->onmax.max_var->var.idx;
3285 unsigned int max_var_ref_idx = data->onmax.max_var_ref_idx;
3286
3287 u64 var_val, max_val;
3288
3289 var_val = var_ref_vals[max_var_ref_idx];
3290 max_val = tracing_map_read_var(elt, max_idx);
3291
3292 if (var_val <= max_val)
3293 return;
3294
3295 tracing_map_set_var(elt, max_idx, var_val);
3296
3297 update_max_vars(hist_data, elt, rbe, rec);
3298 }
3299
3300 static void onmax_destroy(struct action_data *data)
3301 {
3302 unsigned int i;
3303
3304 destroy_hist_field(data->onmax.max_var, 0);
3305 destroy_hist_field(data->onmax.var, 0);
3306
3307 kfree(data->onmax.var_str);
3308 kfree(data->onmax.fn_name);
3309
3310 for (i = 0; i < data->n_params; i++)
3311 kfree(data->params[i]);
3312
3313 kfree(data);
3314 }
3315
3316 static int onmax_create(struct hist_trigger_data *hist_data,
3317 struct action_data *data)
3318 {
3319 struct trace_event_file *file = hist_data->event_file;
3320 struct hist_field *var_field, *ref_field, *max_var;
3321 unsigned int var_ref_idx = hist_data->n_var_refs;
3322 struct field_var *field_var;
3323 char *onmax_var_str, *param;
3324 unsigned long flags;
3325 unsigned int i;
3326 int ret = 0;
3327
3328 onmax_var_str = data->onmax.var_str;
3329 if (onmax_var_str[0] != '$') {
3330 hist_err("onmax: For onmax(x), x must be a variable: ", onmax_var_str);
3331 return -EINVAL;
3332 }
3333 onmax_var_str++;
3334
3335 var_field = find_target_event_var(hist_data, NULL, NULL, onmax_var_str);
3336 if (!var_field) {
3337 hist_err("onmax: Couldn't find onmax variable: ", onmax_var_str);
3338 return -EINVAL;
3339 }
3340
3341 flags = HIST_FIELD_FL_VAR_REF;
3342 ref_field = create_hist_field(hist_data, NULL, flags, NULL);
3343 if (!ref_field)
3344 return -ENOMEM;
3345
3346 if (init_var_ref(ref_field, var_field, NULL, NULL)) {
3347 destroy_hist_field(ref_field, 0);
3348 ret = -ENOMEM;
3349 goto out;
3350 }
3351 hist_data->var_refs[hist_data->n_var_refs] = ref_field;
3352 ref_field->var_ref_idx = hist_data->n_var_refs++;
3353 data->onmax.var = ref_field;
3354
3355 data->fn = onmax_save;
3356 data->onmax.max_var_ref_idx = var_ref_idx;
3357 max_var = create_var(hist_data, file, "max", sizeof(u64), "u64");
3358 if (IS_ERR(max_var)) {
3359 hist_err("onmax: Couldn't create onmax variable: ", "max");
3360 ret = PTR_ERR(max_var);
3361 goto out;
3362 }
3363 data->onmax.max_var = max_var;
3364
3365 for (i = 0; i < data->n_params; i++) {
3366 param = kstrdup(data->params[i], GFP_KERNEL);
3367 if (!param) {
3368 ret = -ENOMEM;
3369 goto out;
3370 }
3371
3372 field_var = create_target_field_var(hist_data, NULL, NULL, param);
3373 if (IS_ERR(field_var)) {
3374 hist_err("onmax: Couldn't create field variable: ", param);
3375 ret = PTR_ERR(field_var);
3376 kfree(param);
3377 goto out;
3378 }
3379
3380 hist_data->max_vars[hist_data->n_max_vars++] = field_var;
3381 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3382 hist_data->n_max_var_str++;
3383
3384 kfree(param);
3385 }
3386 out:
3387 return ret;
3388 }
3389
3390 static int parse_action_params(char *params, struct action_data *data)
3391 {
3392 char *param, *saved_param;
3393 int ret = 0;
3394
3395 while (params) {
3396 if (data->n_params >= SYNTH_FIELDS_MAX)
3397 goto out;
3398
3399 param = strsep(&params, ",");
3400 if (!param) {
3401 ret = -EINVAL;
3402 goto out;
3403 }
3404
3405 param = strstrip(param);
3406 if (strlen(param) < 2) {
3407 hist_err("Invalid action param: ", param);
3408 ret = -EINVAL;
3409 goto out;
3410 }
3411
3412 saved_param = kstrdup(param, GFP_KERNEL);
3413 if (!saved_param) {
3414 ret = -ENOMEM;
3415 goto out;
3416 }
3417
3418 data->params[data->n_params++] = saved_param;
3419 }
3420 out:
3421 return ret;
3422 }
3423
3424 static struct action_data *onmax_parse(char *str)
3425 {
3426 char *onmax_fn_name, *onmax_var_str;
3427 struct action_data *data;
3428 int ret = -EINVAL;
3429
3430 data = kzalloc(sizeof(*data), GFP_KERNEL);
3431 if (!data)
3432 return ERR_PTR(-ENOMEM);
3433
3434 onmax_var_str = strsep(&str, ")");
3435 if (!onmax_var_str || !str) {
3436 ret = -EINVAL;
3437 goto free;
3438 }
3439
3440 data->onmax.var_str = kstrdup(onmax_var_str, GFP_KERNEL);
3441 if (!data->onmax.var_str) {
3442 ret = -ENOMEM;
3443 goto free;
3444 }
3445
3446 strsep(&str, ".");
3447 if (!str)
3448 goto free;
3449
3450 onmax_fn_name = strsep(&str, "(");
3451 if (!onmax_fn_name || !str)
3452 goto free;
3453
3454 if (strncmp(onmax_fn_name, "save", strlen("save")) == 0) {
3455 char *params = strsep(&str, ")");
3456
3457 if (!params) {
3458 ret = -EINVAL;
3459 goto free;
3460 }
3461
3462 ret = parse_action_params(params, data);
3463 if (ret)
3464 goto free;
3465 } else
3466 goto free;
3467
3468 data->onmax.fn_name = kstrdup(onmax_fn_name, GFP_KERNEL);
3469 if (!data->onmax.fn_name) {
3470 ret = -ENOMEM;
3471 goto free;
3472 }
3473 out:
3474 return data;
3475 free:
3476 onmax_destroy(data);
3477 data = ERR_PTR(ret);
3478 goto out;
3479 }
3480
3481 static void onmatch_destroy(struct action_data *data)
3482 {
3483 unsigned int i;
3484
3485 mutex_lock(&synth_event_mutex);
3486
3487 kfree(data->onmatch.match_event);
3488 kfree(data->onmatch.match_event_system);
3489 kfree(data->onmatch.synth_event_name);
3490
3491 for (i = 0; i < data->n_params; i++)
3492 kfree(data->params[i]);
3493
3494 if (data->onmatch.synth_event)
3495 data->onmatch.synth_event->ref--;
3496
3497 kfree(data);
3498
3499 mutex_unlock(&synth_event_mutex);
3500 }
3501
3502 static void destroy_field_var(struct field_var *field_var)
3503 {
3504 if (!field_var)
3505 return;
3506
3507 destroy_hist_field(field_var->var, 0);
3508 destroy_hist_field(field_var->val, 0);
3509
3510 kfree(field_var);
3511 }
3512
3513 static void destroy_field_vars(struct hist_trigger_data *hist_data)
3514 {
3515 unsigned int i;
3516
3517 for (i = 0; i < hist_data->n_field_vars; i++)
3518 destroy_field_var(hist_data->field_vars[i]);
3519 }
3520
3521 static void save_field_var(struct hist_trigger_data *hist_data,
3522 struct field_var *field_var)
3523 {
3524 hist_data->field_vars[hist_data->n_field_vars++] = field_var;
3525
3526 if (field_var->val->flags & HIST_FIELD_FL_STRING)
3527 hist_data->n_field_var_str++;
3528 }
3529
3530
3531 static void destroy_synth_var_refs(struct hist_trigger_data *hist_data)
3532 {
3533 unsigned int i;
3534
3535 for (i = 0; i < hist_data->n_synth_var_refs; i++)
3536 destroy_hist_field(hist_data->synth_var_refs[i], 0);
3537 }
3538
3539 static void save_synth_var_ref(struct hist_trigger_data *hist_data,
3540 struct hist_field *var_ref)
3541 {
3542 hist_data->synth_var_refs[hist_data->n_synth_var_refs++] = var_ref;
3543
3544 hist_data->var_refs[hist_data->n_var_refs] = var_ref;
3545 var_ref->var_ref_idx = hist_data->n_var_refs++;
3546 }
3547
3548 static int check_synth_field(struct synth_event *event,
3549 struct hist_field *hist_field,
3550 unsigned int field_pos)
3551 {
3552 struct synth_field *field;
3553
3554 if (field_pos >= event->n_fields)
3555 return -EINVAL;
3556
3557 field = event->fields[field_pos];
3558
3559 if (strcmp(field->type, hist_field->type) != 0)
3560 return -EINVAL;
3561
3562 return 0;
3563 }
3564
3565 static struct hist_field *
3566 onmatch_find_var(struct hist_trigger_data *hist_data, struct action_data *data,
3567 char *system, char *event, char *var)
3568 {
3569 struct hist_field *hist_field;
3570
3571 var++; /* skip '$' */
3572
3573 hist_field = find_target_event_var(hist_data, system, event, var);
3574 if (!hist_field) {
3575 if (!system) {
3576 system = data->onmatch.match_event_system;
3577 event = data->onmatch.match_event;
3578 }
3579
3580 hist_field = find_event_var(hist_data, system, event, var);
3581 }
3582
3583 if (!hist_field)
3584 hist_err_event("onmatch: Couldn't find onmatch param: $", system, event, var);
3585
3586 return hist_field;
3587 }
3588
3589 static struct hist_field *
3590 onmatch_create_field_var(struct hist_trigger_data *hist_data,
3591 struct action_data *data, char *system,
3592 char *event, char *var)
3593 {
3594 struct hist_field *hist_field = NULL;
3595 struct field_var *field_var;
3596
3597 /*
3598 * First try to create a field var on the target event (the
3599 * currently being defined). This will create a variable for
3600 * unqualified fields on the target event, or if qualified,
3601 * target fields that have qualified names matching the target.
3602 */
3603 field_var = create_target_field_var(hist_data, system, event, var);
3604
3605 if (field_var && !IS_ERR(field_var)) {
3606 save_field_var(hist_data, field_var);
3607 hist_field = field_var->var;
3608 } else {
3609 field_var = NULL;
3610 /*
3611 * If no explicit system.event is specfied, default to
3612 * looking for fields on the onmatch(system.event.xxx)
3613 * event.
3614 */
3615 if (!system) {
3616 system = data->onmatch.match_event_system;
3617 event = data->onmatch.match_event;
3618 }
3619
3620 /*
3621 * At this point, we're looking at a field on another
3622 * event. Because we can't modify a hist trigger on
3623 * another event to add a variable for a field, we need
3624 * to create a new trigger on that event and create the
3625 * variable at the same time.
3626 */
3627 hist_field = create_field_var_hist(hist_data, system, event, var);
3628 if (IS_ERR(hist_field))
3629 goto free;
3630 }
3631 out:
3632 return hist_field;
3633 free:
3634 destroy_field_var(field_var);
3635 hist_field = NULL;
3636 goto out;
3637 }
3638
3639 static int onmatch_create(struct hist_trigger_data *hist_data,
3640 struct trace_event_file *file,
3641 struct action_data *data)
3642 {
3643 char *event_name, *param, *system = NULL;
3644 struct hist_field *hist_field, *var_ref;
3645 unsigned int i, var_ref_idx;
3646 unsigned int field_pos = 0;
3647 struct synth_event *event;
3648 int ret = 0;
3649
3650 mutex_lock(&synth_event_mutex);
3651 event = find_synth_event(data->onmatch.synth_event_name);
3652 if (!event) {
3653 hist_err("onmatch: Couldn't find synthetic event: ", data->onmatch.synth_event_name);
3654 mutex_unlock(&synth_event_mutex);
3655 return -EINVAL;
3656 }
3657 event->ref++;
3658 mutex_unlock(&synth_event_mutex);
3659
3660 var_ref_idx = hist_data->n_var_refs;
3661
3662 for (i = 0; i < data->n_params; i++) {
3663 char *p;
3664
3665 p = param = kstrdup(data->params[i], GFP_KERNEL);
3666 if (!param) {
3667 ret = -ENOMEM;
3668 goto err;
3669 }
3670
3671 system = strsep(&param, ".");
3672 if (!param) {
3673 param = (char *)system;
3674 system = event_name = NULL;
3675 } else {
3676 event_name = strsep(&param, ".");
3677 if (!param) {
3678 kfree(p);
3679 ret = -EINVAL;
3680 goto err;
3681 }
3682 }
3683
3684 if (param[0] == '$')
3685 hist_field = onmatch_find_var(hist_data, data, system,
3686 event_name, param);
3687 else
3688 hist_field = onmatch_create_field_var(hist_data, data,
3689 system,
3690 event_name,
3691 param);
3692
3693 if (!hist_field) {
3694 kfree(p);
3695 ret = -EINVAL;
3696 goto err;
3697 }
3698
3699 if (check_synth_field(event, hist_field, field_pos) == 0) {
3700 var_ref = create_var_ref(hist_field, system, event_name);
3701 if (!var_ref) {
3702 kfree(p);
3703 ret = -ENOMEM;
3704 goto err;
3705 }
3706
3707 save_synth_var_ref(hist_data, var_ref);
3708 field_pos++;
3709 kfree(p);
3710 continue;
3711 }
3712
3713 hist_err_event("onmatch: Param type doesn't match synthetic event field type: ",
3714 system, event_name, param);
3715 kfree(p);
3716 ret = -EINVAL;
3717 goto err;
3718 }
3719
3720 if (field_pos != event->n_fields) {
3721 hist_err("onmatch: Param count doesn't match synthetic event field count: ", event->name);
3722 ret = -EINVAL;
3723 goto err;
3724 }
3725
3726 data->fn = action_trace;
3727 data->onmatch.synth_event = event;
3728 data->onmatch.var_ref_idx = var_ref_idx;
3729 out:
3730 return ret;
3731 err:
3732 mutex_lock(&synth_event_mutex);
3733 event->ref--;
3734 mutex_unlock(&synth_event_mutex);
3735
3736 goto out;
3737 }
3738
3739 static struct action_data *onmatch_parse(struct trace_array *tr, char *str)
3740 {
3741 char *match_event, *match_event_system;
3742 char *synth_event_name, *params;
3743 struct action_data *data;
3744 int ret = -EINVAL;
3745
3746 data = kzalloc(sizeof(*data), GFP_KERNEL);
3747 if (!data)
3748 return ERR_PTR(-ENOMEM);
3749
3750 match_event = strsep(&str, ")");
3751 if (!match_event || !str) {
3752 hist_err("onmatch: Missing closing paren: ", match_event);
3753 goto free;
3754 }
3755
3756 match_event_system = strsep(&match_event, ".");
3757 if (!match_event) {
3758 hist_err("onmatch: Missing subsystem for match event: ", match_event_system);
3759 goto free;
3760 }
3761
3762 if (IS_ERR(event_file(tr, match_event_system, match_event))) {
3763 hist_err_event("onmatch: Invalid subsystem or event name: ",
3764 match_event_system, match_event, NULL);
3765 goto free;
3766 }
3767
3768 data->onmatch.match_event = kstrdup(match_event, GFP_KERNEL);
3769 if (!data->onmatch.match_event) {
3770 ret = -ENOMEM;
3771 goto free;
3772 }
3773
3774 data->onmatch.match_event_system = kstrdup(match_event_system, GFP_KERNEL);
3775 if (!data->onmatch.match_event_system) {
3776 ret = -ENOMEM;
3777 goto free;
3778 }
3779
3780 strsep(&str, ".");
3781 if (!str) {
3782 hist_err("onmatch: Missing . after onmatch(): ", str);
3783 goto free;
3784 }
3785
3786 synth_event_name = strsep(&str, "(");
3787 if (!synth_event_name || !str) {
3788 hist_err("onmatch: Missing opening paramlist paren: ", synth_event_name);
3789 goto free;
3790 }
3791
3792 data->onmatch.synth_event_name = kstrdup(synth_event_name, GFP_KERNEL);
3793 if (!data->onmatch.synth_event_name) {
3794 ret = -ENOMEM;
3795 goto free;
3796 }
3797
3798 params = strsep(&str, ")");
3799 if (!params || !str || (str && strlen(str))) {
3800 hist_err("onmatch: Missing closing paramlist paren: ", params);
3801 goto free;
3802 }
3803
3804 ret = parse_action_params(params, data);
3805 if (ret)
3806 goto free;
3807 out:
3808 return data;
3809 free:
3810 onmatch_destroy(data);
3811 data = ERR_PTR(ret);
3812 goto out;
3813 }
3814
3815 static int create_hitcount_val(struct hist_trigger_data *hist_data)
3816 {
3817 hist_data->fields[HITCOUNT_IDX] =
3818 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL);
3819 if (!hist_data->fields[HITCOUNT_IDX])
3820 return -ENOMEM;
3821
3822 hist_data->n_vals++;
3823 hist_data->n_fields++;
3824
3825 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX))
3826 return -EINVAL;
3827
3828 return 0;
3829 }
3830
3831 static int __create_val_field(struct hist_trigger_data *hist_data,
3832 unsigned int val_idx,
3833 struct trace_event_file *file,
3834 char *var_name, char *field_str,
3835 unsigned long flags)
3836 {
3837 struct hist_field *hist_field;
3838 int ret = 0;
3839
3840 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0);
3841 if (IS_ERR(hist_field)) {
3842 ret = PTR_ERR(hist_field);
3843 goto out;
3844 }
3845
3846 hist_data->fields[val_idx] = hist_field;
3847
3848 ++hist_data->n_vals;
3849 ++hist_data->n_fields;
3850
3851 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3852 ret = -EINVAL;
3853 out:
3854 return ret;
3855 }
3856
3857 static int create_val_field(struct hist_trigger_data *hist_data,
3858 unsigned int val_idx,
3859 struct trace_event_file *file,
3860 char *field_str)
3861 {
3862 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX))
3863 return -EINVAL;
3864
3865 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
3866 }
3867
3868 static int create_var_field(struct hist_trigger_data *hist_data,
3869 unsigned int val_idx,
3870 struct trace_event_file *file,
3871 char *var_name, char *expr_str)
3872 {
3873 unsigned long flags = 0;
3874
3875 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX))
3876 return -EINVAL;
3877
3878 if (find_var(hist_data, file, var_name) && !hist_data->remove) {
3879 hist_err("Variable already defined: ", var_name);
3880 return -EINVAL;
3881 }
3882
3883 flags |= HIST_FIELD_FL_VAR;
3884 hist_data->n_vars++;
3885 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX))
3886 return -EINVAL;
3887
3888 return __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags);
3889 }
3890
3891 static int create_val_fields(struct hist_trigger_data *hist_data,
3892 struct trace_event_file *file)
3893 {
3894 char *fields_str, *field_str;
3895 unsigned int i, j = 1;
3896 int ret;
3897
3898 ret = create_hitcount_val(hist_data);
3899 if (ret)
3900 goto out;
3901
3902 fields_str = hist_data->attrs->vals_str;
3903 if (!fields_str)
3904 goto out;
3905
3906 strsep(&fields_str, "=");
3907 if (!fields_str)
3908 goto out;
3909
3910 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX &&
3911 j < TRACING_MAP_VALS_MAX; i++) {
3912 field_str = strsep(&fields_str, ",");
3913 if (!field_str)
3914 break;
3915
3916 if (strcmp(field_str, "hitcount") == 0)
3917 continue;
3918
3919 ret = create_val_field(hist_data, j++, file, field_str);
3920 if (ret)
3921 goto out;
3922 }
3923
3924 if (fields_str && (strcmp(fields_str, "hitcount") != 0))
3925 ret = -EINVAL;
3926 out:
3927 return ret;
3928 }
3929
3930 static int create_key_field(struct hist_trigger_data *hist_data,
3931 unsigned int key_idx,
3932 unsigned int key_offset,
3933 struct trace_event_file *file,
3934 char *field_str)
3935 {
3936 struct hist_field *hist_field = NULL;
3937
3938 unsigned long flags = 0;
3939 unsigned int key_size;
3940 int ret = 0;
3941
3942 if (WARN_ON(key_idx >= HIST_FIELDS_MAX))
3943 return -EINVAL;
3944
3945 flags |= HIST_FIELD_FL_KEY;
3946
3947 if (strcmp(field_str, "stacktrace") == 0) {
3948 flags |= HIST_FIELD_FL_STACKTRACE;
3949 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH;
3950 hist_field = create_hist_field(hist_data, NULL, flags, NULL);
3951 } else {
3952 hist_field = parse_expr(hist_data, file, field_str, flags,
3953 NULL, 0);
3954 if (IS_ERR(hist_field)) {
3955 ret = PTR_ERR(hist_field);
3956 goto out;
3957 }
3958
3959 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) {
3960 hist_err("Using variable references as keys not supported: ", field_str);
3961 destroy_hist_field(hist_field, 0);
3962 ret = -EINVAL;
3963 goto out;
3964 }
3965
3966 key_size = hist_field->size;
3967 }
3968
3969 hist_data->fields[key_idx] = hist_field;
3970
3971 key_size = ALIGN(key_size, sizeof(u64));
3972 hist_data->fields[key_idx]->size = key_size;
3973 hist_data->fields[key_idx]->offset = key_offset;
3974
3975 hist_data->key_size += key_size;
3976
3977 if (hist_data->key_size > HIST_KEY_SIZE_MAX) {
3978 ret = -EINVAL;
3979 goto out;
3980 }
3981
3982 hist_data->n_keys++;
3983 hist_data->n_fields++;
3984
3985 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX))
3986 return -EINVAL;
3987
3988 ret = key_size;
3989 out:
3990 return ret;
3991 }
3992
3993 static int create_key_fields(struct hist_trigger_data *hist_data,
3994 struct trace_event_file *file)
3995 {
3996 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals;
3997 char *fields_str, *field_str;
3998 int ret = -EINVAL;
3999
4000 fields_str = hist_data->attrs->keys_str;
4001 if (!fields_str)
4002 goto out;
4003
4004 strsep(&fields_str, "=");
4005 if (!fields_str)
4006 goto out;
4007
4008 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) {
4009 field_str = strsep(&fields_str, ",");
4010 if (!field_str)
4011 break;
4012 ret = create_key_field(hist_data, i, key_offset,
4013 file, field_str);
4014 if (ret < 0)
4015 goto out;
4016 key_offset += ret;
4017 }
4018 if (fields_str) {
4019 ret = -EINVAL;
4020 goto out;
4021 }
4022 ret = 0;
4023 out:
4024 return ret;
4025 }
4026
4027 static int create_var_fields(struct hist_trigger_data *hist_data,
4028 struct trace_event_file *file)
4029 {
4030 unsigned int i, j = hist_data->n_vals;
4031 int ret = 0;
4032
4033 unsigned int n_vars = hist_data->attrs->var_defs.n_vars;
4034
4035 for (i = 0; i < n_vars; i++) {
4036 char *var_name = hist_data->attrs->var_defs.name[i];
4037 char *expr = hist_data->attrs->var_defs.expr[i];
4038
4039 ret = create_var_field(hist_data, j++, file, var_name, expr);
4040 if (ret)
4041 goto out;
4042 }
4043 out:
4044 return ret;
4045 }
4046
4047 static void free_var_defs(struct hist_trigger_data *hist_data)
4048 {
4049 unsigned int i;
4050
4051 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) {
4052 kfree(hist_data->attrs->var_defs.name[i]);
4053 kfree(hist_data->attrs->var_defs.expr[i]);
4054 }
4055
4056 hist_data->attrs->var_defs.n_vars = 0;
4057 }
4058
4059 static int parse_var_defs(struct hist_trigger_data *hist_data)
4060 {
4061 char *s, *str, *var_name, *field_str;
4062 unsigned int i, j, n_vars = 0;
4063 int ret = 0;
4064
4065 for (i = 0; i < hist_data->attrs->n_assignments; i++) {
4066 str = hist_data->attrs->assignment_str[i];
4067 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) {
4068 field_str = strsep(&str, ",");
4069 if (!field_str)
4070 break;
4071
4072 var_name = strsep(&field_str, "=");
4073 if (!var_name || !field_str) {
4074 hist_err("Malformed assignment: ", var_name);
4075 ret = -EINVAL;
4076 goto free;
4077 }
4078
4079 if (n_vars == TRACING_MAP_VARS_MAX) {
4080 hist_err("Too many variables defined: ", var_name);
4081 ret = -EINVAL;
4082 goto free;
4083 }
4084
4085 s = kstrdup(var_name, GFP_KERNEL);
4086 if (!s) {
4087 ret = -ENOMEM;
4088 goto free;
4089 }
4090 hist_data->attrs->var_defs.name[n_vars] = s;
4091
4092 s = kstrdup(field_str, GFP_KERNEL);
4093 if (!s) {
4094 kfree(hist_data->attrs->var_defs.name[n_vars]);
4095 ret = -ENOMEM;
4096 goto free;
4097 }
4098 hist_data->attrs->var_defs.expr[n_vars++] = s;
4099
4100 hist_data->attrs->var_defs.n_vars = n_vars;
4101 }
4102 }
4103
4104 return ret;
4105 free:
4106 free_var_defs(hist_data);
4107
4108 return ret;
4109 }
4110
4111 static int create_hist_fields(struct hist_trigger_data *hist_data,
4112 struct trace_event_file *file)
4113 {
4114 int ret;
4115
4116 ret = parse_var_defs(hist_data);
4117 if (ret)
4118 goto out;
4119
4120 ret = create_val_fields(hist_data, file);
4121 if (ret)
4122 goto out;
4123
4124 ret = create_var_fields(hist_data, file);
4125 if (ret)
4126 goto out;
4127
4128 ret = create_key_fields(hist_data, file);
4129 if (ret)
4130 goto out;
4131 out:
4132 free_var_defs(hist_data);
4133
4134 return ret;
4135 }
4136
4137 static int is_descending(const char *str)
4138 {
4139 if (!str)
4140 return 0;
4141
4142 if (strcmp(str, "descending") == 0)
4143 return 1;
4144
4145 if (strcmp(str, "ascending") == 0)
4146 return 0;
4147
4148 return -EINVAL;
4149 }
4150
4151 static int create_sort_keys(struct hist_trigger_data *hist_data)
4152 {
4153 char *fields_str = hist_data->attrs->sort_key_str;
4154 struct tracing_map_sort_key *sort_key;
4155 int descending, ret = 0;
4156 unsigned int i, j, k;
4157
4158 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */
4159
4160 if (!fields_str)
4161 goto out;
4162
4163 strsep(&fields_str, "=");
4164 if (!fields_str) {
4165 ret = -EINVAL;
4166 goto out;
4167 }
4168
4169 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) {
4170 struct hist_field *hist_field;
4171 char *field_str, *field_name;
4172 const char *test_name;
4173
4174 sort_key = &hist_data->sort_keys[i];
4175
4176 field_str = strsep(&fields_str, ",");
4177 if (!field_str) {
4178 if (i == 0)
4179 ret = -EINVAL;
4180 break;
4181 }
4182
4183 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) {
4184 ret = -EINVAL;
4185 break;
4186 }
4187
4188 field_name = strsep(&field_str, ".");
4189 if (!field_name) {
4190 ret = -EINVAL;
4191 break;
4192 }
4193
4194 if (strcmp(field_name, "hitcount") == 0) {
4195 descending = is_descending(field_str);
4196 if (descending < 0) {
4197 ret = descending;
4198 break;
4199 }
4200 sort_key->descending = descending;
4201 continue;
4202 }
4203
4204 for (j = 1, k = 1; j < hist_data->n_fields; j++) {
4205 unsigned int idx;
4206
4207 hist_field = hist_data->fields[j];
4208 if (hist_field->flags & HIST_FIELD_FL_VAR)
4209 continue;
4210
4211 idx = k++;
4212
4213 test_name = hist_field_name(hist_field, 0);
4214
4215 if (strcmp(field_name, test_name) == 0) {
4216 sort_key->field_idx = idx;
4217 descending = is_descending(field_str);
4218 if (descending < 0) {
4219 ret = descending;
4220 goto out;
4221 }
4222 sort_key->descending = descending;
4223 break;
4224 }
4225 }
4226 if (j == hist_data->n_fields) {
4227 ret = -EINVAL;
4228 break;
4229 }
4230 }
4231
4232 hist_data->n_sort_keys = i;
4233 out:
4234 return ret;
4235 }
4236
4237 static void destroy_actions(struct hist_trigger_data *hist_data)
4238 {
4239 unsigned int i;
4240
4241 for (i = 0; i < hist_data->n_actions; i++) {
4242 struct action_data *data = hist_data->actions[i];
4243
4244 if (data->fn == action_trace)
4245 onmatch_destroy(data);
4246 else if (data->fn == onmax_save)
4247 onmax_destroy(data);
4248 else
4249 kfree(data);
4250 }
4251 }
4252
4253 static int parse_actions(struct hist_trigger_data *hist_data)
4254 {
4255 struct trace_array *tr = hist_data->event_file->tr;
4256 struct action_data *data;
4257 unsigned int i;
4258 int ret = 0;
4259 char *str;
4260
4261 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4262 str = hist_data->attrs->action_str[i];
4263
4264 if (strncmp(str, "onmatch(", strlen("onmatch(")) == 0) {
4265 char *action_str = str + strlen("onmatch(");
4266
4267 data = onmatch_parse(tr, action_str);
4268 if (IS_ERR(data)) {
4269 ret = PTR_ERR(data);
4270 break;
4271 }
4272 data->fn = action_trace;
4273 } else if (strncmp(str, "onmax(", strlen("onmax(")) == 0) {
4274 char *action_str = str + strlen("onmax(");
4275
4276 data = onmax_parse(action_str);
4277 if (IS_ERR(data)) {
4278 ret = PTR_ERR(data);
4279 break;
4280 }
4281 data->fn = onmax_save;
4282 } else {
4283 ret = -EINVAL;
4284 break;
4285 }
4286
4287 hist_data->actions[hist_data->n_actions++] = data;
4288 }
4289
4290 return ret;
4291 }
4292
4293 static int create_actions(struct hist_trigger_data *hist_data,
4294 struct trace_event_file *file)
4295 {
4296 struct action_data *data;
4297 unsigned int i;
4298 int ret = 0;
4299
4300 for (i = 0; i < hist_data->attrs->n_actions; i++) {
4301 data = hist_data->actions[i];
4302
4303 if (data->fn == action_trace) {
4304 ret = onmatch_create(hist_data, file, data);
4305 if (ret)
4306 return ret;
4307 } else if (data->fn == onmax_save) {
4308 ret = onmax_create(hist_data, data);
4309 if (ret)
4310 return ret;
4311 }
4312 }
4313
4314 return ret;
4315 }
4316
4317 static void print_actions(struct seq_file *m,
4318 struct hist_trigger_data *hist_data,
4319 struct tracing_map_elt *elt)
4320 {
4321 unsigned int i;
4322
4323 for (i = 0; i < hist_data->n_actions; i++) {
4324 struct action_data *data = hist_data->actions[i];
4325
4326 if (data->fn == onmax_save)
4327 onmax_print(m, hist_data, elt, data);
4328 }
4329 }
4330
4331 static void print_onmax_spec(struct seq_file *m,
4332 struct hist_trigger_data *hist_data,
4333 struct action_data *data)
4334 {
4335 unsigned int i;
4336
4337 seq_puts(m, ":onmax(");
4338 seq_printf(m, "%s", data->onmax.var_str);
4339 seq_printf(m, ").%s(", data->onmax.fn_name);
4340
4341 for (i = 0; i < hist_data->n_max_vars; i++) {
4342 seq_printf(m, "%s", hist_data->max_vars[i]->var->var.name);
4343 if (i < hist_data->n_max_vars - 1)
4344 seq_puts(m, ",");
4345 }
4346 seq_puts(m, ")");
4347 }
4348
4349 static void print_onmatch_spec(struct seq_file *m,
4350 struct hist_trigger_data *hist_data,
4351 struct action_data *data)
4352 {
4353 unsigned int i;
4354
4355 seq_printf(m, ":onmatch(%s.%s).", data->onmatch.match_event_system,
4356 data->onmatch.match_event);
4357
4358 seq_printf(m, "%s(", data->onmatch.synth_event->name);
4359
4360 for (i = 0; i < data->n_params; i++) {
4361 if (i)
4362 seq_puts(m, ",");
4363 seq_printf(m, "%s", data->params[i]);
4364 }
4365
4366 seq_puts(m, ")");
4367 }
4368
4369 static bool actions_match(struct hist_trigger_data *hist_data,
4370 struct hist_trigger_data *hist_data_test)
4371 {
4372 unsigned int i, j;
4373
4374 if (hist_data->n_actions != hist_data_test->n_actions)
4375 return false;
4376
4377 for (i = 0; i < hist_data->n_actions; i++) {
4378 struct action_data *data = hist_data->actions[i];
4379 struct action_data *data_test = hist_data_test->actions[i];
4380
4381 if (data->fn != data_test->fn)
4382 return false;
4383
4384 if (data->n_params != data_test->n_params)
4385 return false;
4386
4387 for (j = 0; j < data->n_params; j++) {
4388 if (strcmp(data->params[j], data_test->params[j]) != 0)
4389 return false;
4390 }
4391
4392 if (data->fn == action_trace) {
4393 if (strcmp(data->onmatch.synth_event_name,
4394 data_test->onmatch.synth_event_name) != 0)
4395 return false;
4396 if (strcmp(data->onmatch.match_event_system,
4397 data_test->onmatch.match_event_system) != 0)
4398 return false;
4399 if (strcmp(data->onmatch.match_event,
4400 data_test->onmatch.match_event) != 0)
4401 return false;
4402 } else if (data->fn == onmax_save) {
4403 if (strcmp(data->onmax.var_str,
4404 data_test->onmax.var_str) != 0)
4405 return false;
4406 if (strcmp(data->onmax.fn_name,
4407 data_test->onmax.fn_name) != 0)
4408 return false;
4409 }
4410 }
4411
4412 return true;
4413 }
4414
4415
4416 static void print_actions_spec(struct seq_file *m,
4417 struct hist_trigger_data *hist_data)
4418 {
4419 unsigned int i;
4420
4421 for (i = 0; i < hist_data->n_actions; i++) {
4422 struct action_data *data = hist_data->actions[i];
4423
4424 if (data->fn == action_trace)
4425 print_onmatch_spec(m, hist_data, data);
4426 else if (data->fn == onmax_save)
4427 print_onmax_spec(m, hist_data, data);
4428 }
4429 }
4430
4431 static void destroy_field_var_hists(struct hist_trigger_data *hist_data)
4432 {
4433 unsigned int i;
4434
4435 for (i = 0; i < hist_data->n_field_var_hists; i++) {
4436 kfree(hist_data->field_var_hists[i]->cmd);
4437 kfree(hist_data->field_var_hists[i]);
4438 }
4439 }
4440
4441 static void destroy_hist_data(struct hist_trigger_data *hist_data)
4442 {
4443 if (!hist_data)
4444 return;
4445
4446 destroy_hist_trigger_attrs(hist_data->attrs);
4447 destroy_hist_fields(hist_data);
4448 tracing_map_destroy(hist_data->map);
4449
4450 destroy_actions(hist_data);
4451 destroy_field_vars(hist_data);
4452 destroy_field_var_hists(hist_data);
4453 destroy_synth_var_refs(hist_data);
4454
4455 kfree(hist_data);
4456 }
4457
4458 static int create_tracing_map_fields(struct hist_trigger_data *hist_data)
4459 {
4460 struct tracing_map *map = hist_data->map;
4461 struct ftrace_event_field *field;
4462 struct hist_field *hist_field;
4463 int i, idx = 0;
4464
4465 for_each_hist_field(i, hist_data) {
4466 hist_field = hist_data->fields[i];
4467 if (hist_field->flags & HIST_FIELD_FL_KEY) {
4468 tracing_map_cmp_fn_t cmp_fn;
4469
4470 field = hist_field->field;
4471
4472 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE)
4473 cmp_fn = tracing_map_cmp_none;
4474 else if (!field)
4475 cmp_fn = tracing_map_cmp_num(hist_field->size,
4476 hist_field->is_signed);
4477 else if (is_string_field(field))
4478 cmp_fn = tracing_map_cmp_string;
4479 else
4480 cmp_fn = tracing_map_cmp_num(field->size,
4481 field->is_signed);
4482 idx = tracing_map_add_key_field(map,
4483 hist_field->offset,
4484 cmp_fn);
4485 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR))
4486 idx = tracing_map_add_sum_field(map);
4487
4488 if (idx < 0)
4489 return idx;
4490
4491 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4492 idx = tracing_map_add_var(map);
4493 if (idx < 0)
4494 return idx;
4495 hist_field->var.idx = idx;
4496 hist_field->var.hist_data = hist_data;
4497 }
4498 }
4499
4500 return 0;
4501 }
4502
4503 static struct hist_trigger_data *
4504 create_hist_data(unsigned int map_bits,
4505 struct hist_trigger_attrs *attrs,
4506 struct trace_event_file *file,
4507 bool remove)
4508 {
4509 const struct tracing_map_ops *map_ops = NULL;
4510 struct hist_trigger_data *hist_data;
4511 int ret = 0;
4512
4513 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL);
4514 if (!hist_data)
4515 return ERR_PTR(-ENOMEM);
4516
4517 hist_data->attrs = attrs;
4518 hist_data->remove = remove;
4519 hist_data->event_file = file;
4520
4521 ret = parse_actions(hist_data);
4522 if (ret)
4523 goto free;
4524
4525 ret = create_hist_fields(hist_data, file);
4526 if (ret)
4527 goto free;
4528
4529 ret = create_sort_keys(hist_data);
4530 if (ret)
4531 goto free;
4532
4533 map_ops = &hist_trigger_elt_data_ops;
4534
4535 hist_data->map = tracing_map_create(map_bits, hist_data->key_size,
4536 map_ops, hist_data);
4537 if (IS_ERR(hist_data->map)) {
4538 ret = PTR_ERR(hist_data->map);
4539 hist_data->map = NULL;
4540 goto free;
4541 }
4542
4543 ret = create_tracing_map_fields(hist_data);
4544 if (ret)
4545 goto free;
4546 out:
4547 return hist_data;
4548 free:
4549 hist_data->attrs = NULL;
4550
4551 destroy_hist_data(hist_data);
4552
4553 hist_data = ERR_PTR(ret);
4554
4555 goto out;
4556 }
4557
4558 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data,
4559 struct tracing_map_elt *elt, void *rec,
4560 struct ring_buffer_event *rbe,
4561 u64 *var_ref_vals)
4562 {
4563 struct hist_elt_data *elt_data;
4564 struct hist_field *hist_field;
4565 unsigned int i, var_idx;
4566 u64 hist_val;
4567
4568 elt_data = elt->private_data;
4569 elt_data->var_ref_vals = var_ref_vals;
4570
4571 for_each_hist_val_field(i, hist_data) {
4572 hist_field = hist_data->fields[i];
4573 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4574 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4575 var_idx = hist_field->var.idx;
4576 tracing_map_set_var(elt, var_idx, hist_val);
4577 continue;
4578 }
4579 tracing_map_update_sum(elt, i, hist_val);
4580 }
4581
4582 for_each_hist_key_field(i, hist_data) {
4583 hist_field = hist_data->fields[i];
4584 if (hist_field->flags & HIST_FIELD_FL_VAR) {
4585 hist_val = hist_field->fn(hist_field, elt, rbe, rec);
4586 var_idx = hist_field->var.idx;
4587 tracing_map_set_var(elt, var_idx, hist_val);
4588 }
4589 }
4590
4591 update_field_vars(hist_data, elt, rbe, rec);
4592 }
4593
4594 static inline void add_to_key(char *compound_key, void *key,
4595 struct hist_field *key_field, void *rec)
4596 {
4597 size_t size = key_field->size;
4598
4599 if (key_field->flags & HIST_FIELD_FL_STRING) {
4600 struct ftrace_event_field *field;
4601
4602 field = key_field->field;
4603 if (field->filter_type == FILTER_DYN_STRING)
4604 size = *(u32 *)(rec + field->offset) >> 16;
4605 else if (field->filter_type == FILTER_PTR_STRING)
4606 size = strlen(key);
4607 else if (field->filter_type == FILTER_STATIC_STRING)
4608 size = field->size;
4609
4610 /* ensure NULL-termination */
4611 if (size > key_field->size - 1)
4612 size = key_field->size - 1;
4613 }
4614
4615 memcpy(compound_key + key_field->offset, key, size);
4616 }
4617
4618 static void
4619 hist_trigger_actions(struct hist_trigger_data *hist_data,
4620 struct tracing_map_elt *elt, void *rec,
4621 struct ring_buffer_event *rbe, u64 *var_ref_vals)
4622 {
4623 struct action_data *data;
4624 unsigned int i;
4625
4626 for (i = 0; i < hist_data->n_actions; i++) {
4627 data = hist_data->actions[i];
4628 data->fn(hist_data, elt, rec, rbe, data, var_ref_vals);
4629 }
4630 }
4631
4632 static void event_hist_trigger(struct event_trigger_data *data, void *rec,
4633 struct ring_buffer_event *rbe)
4634 {
4635 struct hist_trigger_data *hist_data = data->private_data;
4636 bool use_compound_key = (hist_data->n_keys > 1);
4637 unsigned long entries[HIST_STACKTRACE_DEPTH];
4638 u64 var_ref_vals[TRACING_MAP_VARS_MAX];
4639 char compound_key[HIST_KEY_SIZE_MAX];
4640 struct tracing_map_elt *elt = NULL;
4641 struct stack_trace stacktrace;
4642 struct hist_field *key_field;
4643 u64 field_contents;
4644 void *key = NULL;
4645 unsigned int i;
4646
4647 memset(compound_key, 0, hist_data->key_size);
4648
4649 for_each_hist_key_field(i, hist_data) {
4650 key_field = hist_data->fields[i];
4651
4652 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4653 stacktrace.max_entries = HIST_STACKTRACE_DEPTH;
4654 stacktrace.entries = entries;
4655 stacktrace.nr_entries = 0;
4656 stacktrace.skip = HIST_STACKTRACE_SKIP;
4657
4658 memset(stacktrace.entries, 0, HIST_STACKTRACE_SIZE);
4659 save_stack_trace(&stacktrace);
4660
4661 key = entries;
4662 } else {
4663 field_contents = key_field->fn(key_field, elt, rbe, rec);
4664 if (key_field->flags & HIST_FIELD_FL_STRING) {
4665 key = (void *)(unsigned long)field_contents;
4666 use_compound_key = true;
4667 } else
4668 key = (void *)&field_contents;
4669 }
4670
4671 if (use_compound_key)
4672 add_to_key(compound_key, key, key_field, rec);
4673 }
4674
4675 if (use_compound_key)
4676 key = compound_key;
4677
4678 if (hist_data->n_var_refs &&
4679 !resolve_var_refs(hist_data, key, var_ref_vals, false))
4680 return;
4681
4682 elt = tracing_map_insert(hist_data->map, key);
4683 if (!elt)
4684 return;
4685
4686 hist_trigger_elt_update(hist_data, elt, rec, rbe, var_ref_vals);
4687
4688 if (resolve_var_refs(hist_data, key, var_ref_vals, true))
4689 hist_trigger_actions(hist_data, elt, rec, rbe, var_ref_vals);
4690 }
4691
4692 static void hist_trigger_stacktrace_print(struct seq_file *m,
4693 unsigned long *stacktrace_entries,
4694 unsigned int max_entries)
4695 {
4696 char str[KSYM_SYMBOL_LEN];
4697 unsigned int spaces = 8;
4698 unsigned int i;
4699
4700 for (i = 0; i < max_entries; i++) {
4701 if (stacktrace_entries[i] == ULONG_MAX)
4702 return;
4703
4704 seq_printf(m, "%*c", 1 + spaces, ' ');
4705 sprint_symbol(str, stacktrace_entries[i]);
4706 seq_printf(m, "%s\n", str);
4707 }
4708 }
4709
4710 static void
4711 hist_trigger_entry_print(struct seq_file *m,
4712 struct hist_trigger_data *hist_data, void *key,
4713 struct tracing_map_elt *elt)
4714 {
4715 struct hist_field *key_field;
4716 char str[KSYM_SYMBOL_LEN];
4717 bool multiline = false;
4718 const char *field_name;
4719 unsigned int i;
4720 u64 uval;
4721
4722 seq_puts(m, "{ ");
4723
4724 for_each_hist_key_field(i, hist_data) {
4725 key_field = hist_data->fields[i];
4726
4727 if (i > hist_data->n_vals)
4728 seq_puts(m, ", ");
4729
4730 field_name = hist_field_name(key_field, 0);
4731
4732 if (key_field->flags & HIST_FIELD_FL_HEX) {
4733 uval = *(u64 *)(key + key_field->offset);
4734 seq_printf(m, "%s: %llx", field_name, uval);
4735 } else if (key_field->flags & HIST_FIELD_FL_SYM) {
4736 uval = *(u64 *)(key + key_field->offset);
4737 sprint_symbol_no_offset(str, uval);
4738 seq_printf(m, "%s: [%llx] %-45s", field_name,
4739 uval, str);
4740 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) {
4741 uval = *(u64 *)(key + key_field->offset);
4742 sprint_symbol(str, uval);
4743 seq_printf(m, "%s: [%llx] %-55s", field_name,
4744 uval, str);
4745 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
4746 struct hist_elt_data *elt_data = elt->private_data;
4747 char *comm;
4748
4749 if (WARN_ON_ONCE(!elt_data))
4750 return;
4751
4752 comm = elt_data->comm;
4753
4754 uval = *(u64 *)(key + key_field->offset);
4755 seq_printf(m, "%s: %-16s[%10llu]", field_name,
4756 comm, uval);
4757 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) {
4758 const char *syscall_name;
4759
4760 uval = *(u64 *)(key + key_field->offset);
4761 syscall_name = get_syscall_name(uval);
4762 if (!syscall_name)
4763 syscall_name = "unknown_syscall";
4764
4765 seq_printf(m, "%s: %-30s[%3llu]", field_name,
4766 syscall_name, uval);
4767 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) {
4768 seq_puts(m, "stacktrace:\n");
4769 hist_trigger_stacktrace_print(m,
4770 key + key_field->offset,
4771 HIST_STACKTRACE_DEPTH);
4772 multiline = true;
4773 } else if (key_field->flags & HIST_FIELD_FL_LOG2) {
4774 seq_printf(m, "%s: ~ 2^%-2llu", field_name,
4775 *(u64 *)(key + key_field->offset));
4776 } else if (key_field->flags & HIST_FIELD_FL_STRING) {
4777 seq_printf(m, "%s: %-50s", field_name,
4778 (char *)(key + key_field->offset));
4779 } else {
4780 uval = *(u64 *)(key + key_field->offset);
4781 seq_printf(m, "%s: %10llu", field_name, uval);
4782 }
4783 }
4784
4785 if (!multiline)
4786 seq_puts(m, " ");
4787
4788 seq_puts(m, "}");
4789
4790 seq_printf(m, " hitcount: %10llu",
4791 tracing_map_read_sum(elt, HITCOUNT_IDX));
4792
4793 for (i = 1; i < hist_data->n_vals; i++) {
4794 field_name = hist_field_name(hist_data->fields[i], 0);
4795
4796 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR ||
4797 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR)
4798 continue;
4799
4800 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) {
4801 seq_printf(m, " %s: %10llx", field_name,
4802 tracing_map_read_sum(elt, i));
4803 } else {
4804 seq_printf(m, " %s: %10llu", field_name,
4805 tracing_map_read_sum(elt, i));
4806 }
4807 }
4808
4809 print_actions(m, hist_data, elt);
4810
4811 seq_puts(m, "\n");
4812 }
4813
4814 static int print_entries(struct seq_file *m,
4815 struct hist_trigger_data *hist_data)
4816 {
4817 struct tracing_map_sort_entry **sort_entries = NULL;
4818 struct tracing_map *map = hist_data->map;
4819 int i, n_entries;
4820
4821 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys,
4822 hist_data->n_sort_keys,
4823 &sort_entries);
4824 if (n_entries < 0)
4825 return n_entries;
4826
4827 for (i = 0; i < n_entries; i++)
4828 hist_trigger_entry_print(m, hist_data,
4829 sort_entries[i]->key,
4830 sort_entries[i]->elt);
4831
4832 tracing_map_destroy_sort_entries(sort_entries, n_entries);
4833
4834 return n_entries;
4835 }
4836
4837 static void hist_trigger_show(struct seq_file *m,
4838 struct event_trigger_data *data, int n)
4839 {
4840 struct hist_trigger_data *hist_data;
4841 int n_entries;
4842
4843 if (n > 0)
4844 seq_puts(m, "\n\n");
4845
4846 seq_puts(m, "# event histogram\n#\n# trigger info: ");
4847 data->ops->print(m, data->ops, data);
4848 seq_puts(m, "#\n\n");
4849
4850 hist_data = data->private_data;
4851 n_entries = print_entries(m, hist_data);
4852 if (n_entries < 0)
4853 n_entries = 0;
4854
4855 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n",
4856 (u64)atomic64_read(&hist_data->map->hits),
4857 n_entries, (u64)atomic64_read(&hist_data->map->drops));
4858 }
4859
4860 static int hist_show(struct seq_file *m, void *v)
4861 {
4862 struct event_trigger_data *data;
4863 struct trace_event_file *event_file;
4864 int n = 0, ret = 0;
4865
4866 mutex_lock(&event_mutex);
4867
4868 event_file = event_file_data(m->private);
4869 if (unlikely(!event_file)) {
4870 ret = -ENODEV;
4871 goto out_unlock;
4872 }
4873
4874 list_for_each_entry_rcu(data, &event_file->triggers, list) {
4875 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST)
4876 hist_trigger_show(m, data, n++);
4877 }
4878
4879 if (have_hist_err()) {
4880 seq_printf(m, "\nERROR: %s\n", hist_err_str);
4881 seq_printf(m, " Last command: %s\n", last_hist_cmd);
4882 }
4883
4884 out_unlock:
4885 mutex_unlock(&event_mutex);
4886
4887 return ret;
4888 }
4889
4890 static int event_hist_open(struct inode *inode, struct file *file)
4891 {
4892 return single_open(file, hist_show, file);
4893 }
4894
4895 const struct file_operations event_hist_fops = {
4896 .open = event_hist_open,
4897 .read = seq_read,
4898 .llseek = seq_lseek,
4899 .release = single_release,
4900 };
4901
4902 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
4903 {
4904 const char *field_name = hist_field_name(hist_field, 0);
4905
4906 if (hist_field->var.name)
4907 seq_printf(m, "%s=", hist_field->var.name);
4908
4909 if (hist_field->flags & HIST_FIELD_FL_CPU)
4910 seq_puts(m, "cpu");
4911 else if (field_name) {
4912 if (hist_field->flags & HIST_FIELD_FL_VAR_REF ||
4913 hist_field->flags & HIST_FIELD_FL_ALIAS)
4914 seq_putc(m, '$');
4915 seq_printf(m, "%s", field_name);
4916 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP)
4917 seq_puts(m, "common_timestamp");
4918
4919 if (hist_field->flags) {
4920 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) &&
4921 !(hist_field->flags & HIST_FIELD_FL_EXPR)) {
4922 const char *flags = get_hist_field_flags(hist_field);
4923
4924 if (flags)
4925 seq_printf(m, ".%s", flags);
4926 }
4927 }
4928 }
4929
4930 static int event_hist_trigger_print(struct seq_file *m,
4931 struct event_trigger_ops *ops,
4932 struct event_trigger_data *data)
4933 {
4934 struct hist_trigger_data *hist_data = data->private_data;
4935 struct hist_field *field;
4936 bool have_var = false;
4937 unsigned int i;
4938
4939 seq_puts(m, "hist:");
4940
4941 if (data->name)
4942 seq_printf(m, "%s:", data->name);
4943
4944 seq_puts(m, "keys=");
4945
4946 for_each_hist_key_field(i, hist_data) {
4947 field = hist_data->fields[i];
4948
4949 if (i > hist_data->n_vals)
4950 seq_puts(m, ",");
4951
4952 if (field->flags & HIST_FIELD_FL_STACKTRACE)
4953 seq_puts(m, "stacktrace");
4954 else
4955 hist_field_print(m, field);
4956 }
4957
4958 seq_puts(m, ":vals=");
4959
4960 for_each_hist_val_field(i, hist_data) {
4961 field = hist_data->fields[i];
4962 if (field->flags & HIST_FIELD_FL_VAR) {
4963 have_var = true;
4964 continue;
4965 }
4966
4967 if (i == HITCOUNT_IDX)
4968 seq_puts(m, "hitcount");
4969 else {
4970 seq_puts(m, ",");
4971 hist_field_print(m, field);
4972 }
4973 }
4974
4975 if (have_var) {
4976 unsigned int n = 0;
4977
4978 seq_puts(m, ":");
4979
4980 for_each_hist_val_field(i, hist_data) {
4981 field = hist_data->fields[i];
4982
4983 if (field->flags & HIST_FIELD_FL_VAR) {
4984 if (n++)
4985 seq_puts(m, ",");
4986 hist_field_print(m, field);
4987 }
4988 }
4989 }
4990
4991 seq_puts(m, ":sort=");
4992
4993 for (i = 0; i < hist_data->n_sort_keys; i++) {
4994 struct tracing_map_sort_key *sort_key;
4995 unsigned int idx, first_key_idx;
4996
4997 /* skip VAR vals */
4998 first_key_idx = hist_data->n_vals - hist_data->n_vars;
4999
5000 sort_key = &hist_data->sort_keys[i];
5001 idx = sort_key->field_idx;
5002
5003 if (WARN_ON(idx >= HIST_FIELDS_MAX))
5004 return -EINVAL;
5005
5006 if (i > 0)
5007 seq_puts(m, ",");
5008
5009 if (idx == HITCOUNT_IDX)
5010 seq_puts(m, "hitcount");
5011 else {
5012 if (idx >= first_key_idx)
5013 idx += hist_data->n_vars;
5014 hist_field_print(m, hist_data->fields[idx]);
5015 }
5016
5017 if (sort_key->descending)
5018 seq_puts(m, ".descending");
5019 }
5020 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits));
5021 if (hist_data->enable_timestamps)
5022 seq_printf(m, ":clock=%s", hist_data->attrs->clock);
5023
5024 print_actions_spec(m, hist_data);
5025
5026 if (data->filter_str)
5027 seq_printf(m, " if %s", data->filter_str);
5028
5029 if (data->paused)
5030 seq_puts(m, " [paused]");
5031 else
5032 seq_puts(m, " [active]");
5033
5034 seq_putc(m, '\n');
5035
5036 return 0;
5037 }
5038
5039 static int event_hist_trigger_init(struct event_trigger_ops *ops,
5040 struct event_trigger_data *data)
5041 {
5042 struct hist_trigger_data *hist_data = data->private_data;
5043
5044 if (!data->ref && hist_data->attrs->name)
5045 save_named_trigger(hist_data->attrs->name, data);
5046
5047 data->ref++;
5048
5049 return 0;
5050 }
5051
5052 static void unregister_field_var_hists(struct hist_trigger_data *hist_data)
5053 {
5054 struct trace_event_file *file;
5055 unsigned int i;
5056 char *cmd;
5057 int ret;
5058
5059 for (i = 0; i < hist_data->n_field_var_hists; i++) {
5060 file = hist_data->field_var_hists[i]->hist_data->event_file;
5061 cmd = hist_data->field_var_hists[i]->cmd;
5062 ret = event_hist_trigger_func(&trigger_hist_cmd, file,
5063 "!hist", "hist", cmd);
5064 }
5065 }
5066
5067 static void event_hist_trigger_free(struct event_trigger_ops *ops,
5068 struct event_trigger_data *data)
5069 {
5070 struct hist_trigger_data *hist_data = data->private_data;
5071
5072 if (WARN_ON_ONCE(data->ref <= 0))
5073 return;
5074
5075 data->ref--;
5076 if (!data->ref) {
5077 if (data->name)
5078 del_named_trigger(data);
5079
5080 trigger_data_free(data);
5081
5082 remove_hist_vars(hist_data);
5083
5084 unregister_field_var_hists(hist_data);
5085
5086 destroy_hist_data(hist_data);
5087 }
5088 }
5089
5090 static struct event_trigger_ops event_hist_trigger_ops = {
5091 .func = event_hist_trigger,
5092 .print = event_hist_trigger_print,
5093 .init = event_hist_trigger_init,
5094 .free = event_hist_trigger_free,
5095 };
5096
5097 static int event_hist_trigger_named_init(struct event_trigger_ops *ops,
5098 struct event_trigger_data *data)
5099 {
5100 data->ref++;
5101
5102 save_named_trigger(data->named_data->name, data);
5103
5104 event_hist_trigger_init(ops, data->named_data);
5105
5106 return 0;
5107 }
5108
5109 static void event_hist_trigger_named_free(struct event_trigger_ops *ops,
5110 struct event_trigger_data *data)
5111 {
5112 if (WARN_ON_ONCE(data->ref <= 0))
5113 return;
5114
5115 event_hist_trigger_free(ops, data->named_data);
5116
5117 data->ref--;
5118 if (!data->ref) {
5119 del_named_trigger(data);
5120 trigger_data_free(data);
5121 }
5122 }
5123
5124 static struct event_trigger_ops event_hist_trigger_named_ops = {
5125 .func = event_hist_trigger,
5126 .print = event_hist_trigger_print,
5127 .init = event_hist_trigger_named_init,
5128 .free = event_hist_trigger_named_free,
5129 };
5130
5131 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd,
5132 char *param)
5133 {
5134 return &event_hist_trigger_ops;
5135 }
5136
5137 static void hist_clear(struct event_trigger_data *data)
5138 {
5139 struct hist_trigger_data *hist_data = data->private_data;
5140
5141 if (data->name)
5142 pause_named_trigger(data);
5143
5144 synchronize_sched();
5145
5146 tracing_map_clear(hist_data->map);
5147
5148 if (data->name)
5149 unpause_named_trigger(data);
5150 }
5151
5152 static bool compatible_field(struct ftrace_event_field *field,
5153 struct ftrace_event_field *test_field)
5154 {
5155 if (field == test_field)
5156 return true;
5157 if (field == NULL || test_field == NULL)
5158 return false;
5159 if (strcmp(field->name, test_field->name) != 0)
5160 return false;
5161 if (strcmp(field->type, test_field->type) != 0)
5162 return false;
5163 if (field->size != test_field->size)
5164 return false;
5165 if (field->is_signed != test_field->is_signed)
5166 return false;
5167
5168 return true;
5169 }
5170
5171 static bool hist_trigger_match(struct event_trigger_data *data,
5172 struct event_trigger_data *data_test,
5173 struct event_trigger_data *named_data,
5174 bool ignore_filter)
5175 {
5176 struct tracing_map_sort_key *sort_key, *sort_key_test;
5177 struct hist_trigger_data *hist_data, *hist_data_test;
5178 struct hist_field *key_field, *key_field_test;
5179 unsigned int i;
5180
5181 if (named_data && (named_data != data_test) &&
5182 (named_data != data_test->named_data))
5183 return false;
5184
5185 if (!named_data && is_named_trigger(data_test))
5186 return false;
5187
5188 hist_data = data->private_data;
5189 hist_data_test = data_test->private_data;
5190
5191 if (hist_data->n_vals != hist_data_test->n_vals ||
5192 hist_data->n_fields != hist_data_test->n_fields ||
5193 hist_data->n_sort_keys != hist_data_test->n_sort_keys)
5194 return false;
5195
5196 if (!ignore_filter) {
5197 if ((data->filter_str && !data_test->filter_str) ||
5198 (!data->filter_str && data_test->filter_str))
5199 return false;
5200 }
5201
5202 for_each_hist_field(i, hist_data) {
5203 key_field = hist_data->fields[i];
5204 key_field_test = hist_data_test->fields[i];
5205
5206 if (key_field->flags != key_field_test->flags)
5207 return false;
5208 if (!compatible_field(key_field->field, key_field_test->field))
5209 return false;
5210 if (key_field->offset != key_field_test->offset)
5211 return false;
5212 if (key_field->size != key_field_test->size)
5213 return false;
5214 if (key_field->is_signed != key_field_test->is_signed)
5215 return false;
5216 if (!!key_field->var.name != !!key_field_test->var.name)
5217 return false;
5218 if (key_field->var.name &&
5219 strcmp(key_field->var.name, key_field_test->var.name) != 0)
5220 return false;
5221 }
5222
5223 for (i = 0; i < hist_data->n_sort_keys; i++) {
5224 sort_key = &hist_data->sort_keys[i];
5225 sort_key_test = &hist_data_test->sort_keys[i];
5226
5227 if (sort_key->field_idx != sort_key_test->field_idx ||
5228 sort_key->descending != sort_key_test->descending)
5229 return false;
5230 }
5231
5232 if (!ignore_filter && data->filter_str &&
5233 (strcmp(data->filter_str, data_test->filter_str) != 0))
5234 return false;
5235
5236 if (!actions_match(hist_data, hist_data_test))
5237 return false;
5238
5239 return true;
5240 }
5241
5242 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops,
5243 struct event_trigger_data *data,
5244 struct trace_event_file *file)
5245 {
5246 struct hist_trigger_data *hist_data = data->private_data;
5247 struct event_trigger_data *test, *named_data = NULL;
5248 int ret = 0;
5249
5250 if (hist_data->attrs->name) {
5251 named_data = find_named_trigger(hist_data->attrs->name);
5252 if (named_data) {
5253 if (!hist_trigger_match(data, named_data, named_data,
5254 true)) {
5255 hist_err("Named hist trigger doesn't match existing named trigger (includes variables): ", hist_data->attrs->name);
5256 ret = -EINVAL;
5257 goto out;
5258 }
5259 }
5260 }
5261
5262 if (hist_data->attrs->name && !named_data)
5263 goto new;
5264
5265 list_for_each_entry_rcu(test, &file->triggers, list) {
5266 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5267 if (!hist_trigger_match(data, test, named_data, false))
5268 continue;
5269 if (hist_data->attrs->pause)
5270 test->paused = true;
5271 else if (hist_data->attrs->cont)
5272 test->paused = false;
5273 else if (hist_data->attrs->clear)
5274 hist_clear(test);
5275 else {
5276 hist_err("Hist trigger already exists", NULL);
5277 ret = -EEXIST;
5278 }
5279 goto out;
5280 }
5281 }
5282 new:
5283 if (hist_data->attrs->cont || hist_data->attrs->clear) {
5284 hist_err("Can't clear or continue a nonexistent hist trigger", NULL);
5285 ret = -ENOENT;
5286 goto out;
5287 }
5288
5289 if (hist_data->attrs->pause)
5290 data->paused = true;
5291
5292 if (named_data) {
5293 data->private_data = named_data->private_data;
5294 set_named_trigger_data(data, named_data);
5295 data->ops = &event_hist_trigger_named_ops;
5296 }
5297
5298 if (data->ops->init) {
5299 ret = data->ops->init(data->ops, data);
5300 if (ret < 0)
5301 goto out;
5302 }
5303
5304 if (hist_data->enable_timestamps) {
5305 char *clock = hist_data->attrs->clock;
5306
5307 ret = tracing_set_clock(file->tr, hist_data->attrs->clock);
5308 if (ret) {
5309 hist_err("Couldn't set trace_clock: ", clock);
5310 goto out;
5311 }
5312
5313 tracing_set_time_stamp_abs(file->tr, true);
5314 }
5315
5316 if (named_data)
5317 destroy_hist_data(hist_data);
5318
5319 ret++;
5320 out:
5321 return ret;
5322 }
5323
5324 static int hist_trigger_enable(struct event_trigger_data *data,
5325 struct trace_event_file *file)
5326 {
5327 int ret = 0;
5328
5329 list_add_tail_rcu(&data->list, &file->triggers);
5330
5331 update_cond_flag(file);
5332
5333 if (trace_event_trigger_enable_disable(file, 1) < 0) {
5334 list_del_rcu(&data->list);
5335 update_cond_flag(file);
5336 ret--;
5337 }
5338
5339 return ret;
5340 }
5341
5342 static bool have_hist_trigger_match(struct event_trigger_data *data,
5343 struct trace_event_file *file)
5344 {
5345 struct hist_trigger_data *hist_data = data->private_data;
5346 struct event_trigger_data *test, *named_data = NULL;
5347 bool match = false;
5348
5349 if (hist_data->attrs->name)
5350 named_data = find_named_trigger(hist_data->attrs->name);
5351
5352 list_for_each_entry_rcu(test, &file->triggers, list) {
5353 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5354 if (hist_trigger_match(data, test, named_data, false)) {
5355 match = true;
5356 break;
5357 }
5358 }
5359 }
5360
5361 return match;
5362 }
5363
5364 static bool hist_trigger_check_refs(struct event_trigger_data *data,
5365 struct trace_event_file *file)
5366 {
5367 struct hist_trigger_data *hist_data = data->private_data;
5368 struct event_trigger_data *test, *named_data = NULL;
5369
5370 if (hist_data->attrs->name)
5371 named_data = find_named_trigger(hist_data->attrs->name);
5372
5373 list_for_each_entry_rcu(test, &file->triggers, list) {
5374 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5375 if (!hist_trigger_match(data, test, named_data, false))
5376 continue;
5377 hist_data = test->private_data;
5378 if (check_var_refs(hist_data))
5379 return true;
5380 break;
5381 }
5382 }
5383
5384 return false;
5385 }
5386
5387 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops,
5388 struct event_trigger_data *data,
5389 struct trace_event_file *file)
5390 {
5391 struct hist_trigger_data *hist_data = data->private_data;
5392 struct event_trigger_data *test, *named_data = NULL;
5393 bool unregistered = false;
5394
5395 if (hist_data->attrs->name)
5396 named_data = find_named_trigger(hist_data->attrs->name);
5397
5398 list_for_each_entry_rcu(test, &file->triggers, list) {
5399 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5400 if (!hist_trigger_match(data, test, named_data, false))
5401 continue;
5402 unregistered = true;
5403 list_del_rcu(&test->list);
5404 trace_event_trigger_enable_disable(file, 0);
5405 update_cond_flag(file);
5406 break;
5407 }
5408 }
5409
5410 if (unregistered && test->ops->free)
5411 test->ops->free(test->ops, test);
5412
5413 if (hist_data->enable_timestamps) {
5414 if (!hist_data->remove || unregistered)
5415 tracing_set_time_stamp_abs(file->tr, false);
5416 }
5417 }
5418
5419 static bool hist_file_check_refs(struct trace_event_file *file)
5420 {
5421 struct hist_trigger_data *hist_data;
5422 struct event_trigger_data *test;
5423
5424 list_for_each_entry_rcu(test, &file->triggers, list) {
5425 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5426 hist_data = test->private_data;
5427 if (check_var_refs(hist_data))
5428 return true;
5429 }
5430 }
5431
5432 return false;
5433 }
5434
5435 static void hist_unreg_all(struct trace_event_file *file)
5436 {
5437 struct event_trigger_data *test, *n;
5438 struct hist_trigger_data *hist_data;
5439 struct synth_event *se;
5440 const char *se_name;
5441
5442 if (hist_file_check_refs(file))
5443 return;
5444
5445 list_for_each_entry_safe(test, n, &file->triggers, list) {
5446 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5447 hist_data = test->private_data;
5448 list_del_rcu(&test->list);
5449 trace_event_trigger_enable_disable(file, 0);
5450
5451 mutex_lock(&synth_event_mutex);
5452 se_name = trace_event_name(file->event_call);
5453 se = find_synth_event(se_name);
5454 if (se)
5455 se->ref--;
5456 mutex_unlock(&synth_event_mutex);
5457
5458 update_cond_flag(file);
5459 if (hist_data->enable_timestamps)
5460 tracing_set_time_stamp_abs(file->tr, false);
5461 if (test->ops->free)
5462 test->ops->free(test->ops, test);
5463 }
5464 }
5465 }
5466
5467 static int event_hist_trigger_func(struct event_command *cmd_ops,
5468 struct trace_event_file *file,
5469 char *glob, char *cmd, char *param)
5470 {
5471 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT;
5472 struct event_trigger_data *trigger_data;
5473 struct hist_trigger_attrs *attrs;
5474 struct event_trigger_ops *trigger_ops;
5475 struct hist_trigger_data *hist_data;
5476 struct synth_event *se;
5477 const char *se_name;
5478 bool remove = false;
5479 char *trigger, *p;
5480 int ret = 0;
5481
5482 if (glob && strlen(glob)) {
5483 last_cmd_set(param);
5484 hist_err_clear();
5485 }
5486
5487 if (!param)
5488 return -EINVAL;
5489
5490 if (glob[0] == '!')
5491 remove = true;
5492
5493 /*
5494 * separate the trigger from the filter (k:v [if filter])
5495 * allowing for whitespace in the trigger
5496 */
5497 p = trigger = param;
5498 do {
5499 p = strstr(p, "if");
5500 if (!p)
5501 break;
5502 if (p == param)
5503 return -EINVAL;
5504 if (*(p - 1) != ' ' && *(p - 1) != '\t') {
5505 p++;
5506 continue;
5507 }
5508 if (p >= param + strlen(param) - strlen("if") - 1)
5509 return -EINVAL;
5510 if (*(p + strlen("if")) != ' ' && *(p + strlen("if")) != '\t') {
5511 p++;
5512 continue;
5513 }
5514 break;
5515 } while (p);
5516
5517 if (!p)
5518 param = NULL;
5519 else {
5520 *(p - 1) = '\0';
5521 param = strstrip(p);
5522 trigger = strstrip(trigger);
5523 }
5524
5525 attrs = parse_hist_trigger_attrs(trigger);
5526 if (IS_ERR(attrs))
5527 return PTR_ERR(attrs);
5528
5529 if (attrs->map_bits)
5530 hist_trigger_bits = attrs->map_bits;
5531
5532 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove);
5533 if (IS_ERR(hist_data)) {
5534 destroy_hist_trigger_attrs(attrs);
5535 return PTR_ERR(hist_data);
5536 }
5537
5538 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger);
5539
5540 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL);
5541 if (!trigger_data) {
5542 ret = -ENOMEM;
5543 goto out_free;
5544 }
5545
5546 trigger_data->count = -1;
5547 trigger_data->ops = trigger_ops;
5548 trigger_data->cmd_ops = cmd_ops;
5549
5550 INIT_LIST_HEAD(&trigger_data->list);
5551 RCU_INIT_POINTER(trigger_data->filter, NULL);
5552
5553 trigger_data->private_data = hist_data;
5554
5555 /* if param is non-empty, it's supposed to be a filter */
5556 if (param && cmd_ops->set_filter) {
5557 ret = cmd_ops->set_filter(param, trigger_data, file);
5558 if (ret < 0)
5559 goto out_free;
5560 }
5561
5562 if (remove) {
5563 if (!have_hist_trigger_match(trigger_data, file))
5564 goto out_free;
5565
5566 if (hist_trigger_check_refs(trigger_data, file)) {
5567 ret = -EBUSY;
5568 goto out_free;
5569 }
5570
5571 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5572
5573 mutex_lock(&synth_event_mutex);
5574 se_name = trace_event_name(file->event_call);
5575 se = find_synth_event(se_name);
5576 if (se)
5577 se->ref--;
5578 mutex_unlock(&synth_event_mutex);
5579
5580 ret = 0;
5581 goto out_free;
5582 }
5583
5584 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file);
5585 /*
5586 * The above returns on success the # of triggers registered,
5587 * but if it didn't register any it returns zero. Consider no
5588 * triggers registered a failure too.
5589 */
5590 if (!ret) {
5591 if (!(attrs->pause || attrs->cont || attrs->clear))
5592 ret = -ENOENT;
5593 goto out_free;
5594 } else if (ret < 0)
5595 goto out_free;
5596
5597 if (get_named_trigger_data(trigger_data))
5598 goto enable;
5599
5600 if (has_hist_vars(hist_data))
5601 save_hist_vars(hist_data);
5602
5603 ret = create_actions(hist_data, file);
5604 if (ret)
5605 goto out_unreg;
5606
5607 ret = tracing_map_init(hist_data->map);
5608 if (ret)
5609 goto out_unreg;
5610 enable:
5611 ret = hist_trigger_enable(trigger_data, file);
5612 if (ret)
5613 goto out_unreg;
5614
5615 mutex_lock(&synth_event_mutex);
5616 se_name = trace_event_name(file->event_call);
5617 se = find_synth_event(se_name);
5618 if (se)
5619 se->ref++;
5620 mutex_unlock(&synth_event_mutex);
5621
5622 /* Just return zero, not the number of registered triggers */
5623 ret = 0;
5624 out:
5625 if (ret == 0)
5626 hist_err_clear();
5627
5628 return ret;
5629 out_unreg:
5630 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file);
5631 out_free:
5632 if (cmd_ops->set_filter)
5633 cmd_ops->set_filter(NULL, trigger_data, NULL);
5634
5635 remove_hist_vars(hist_data);
5636
5637 kfree(trigger_data);
5638
5639 destroy_hist_data(hist_data);
5640 goto out;
5641 }
5642
5643 static struct event_command trigger_hist_cmd = {
5644 .name = "hist",
5645 .trigger_type = ETT_EVENT_HIST,
5646 .flags = EVENT_CMD_FL_NEEDS_REC,
5647 .func = event_hist_trigger_func,
5648 .reg = hist_register_trigger,
5649 .unreg = hist_unregister_trigger,
5650 .unreg_all = hist_unreg_all,
5651 .get_trigger_ops = event_hist_get_trigger_ops,
5652 .set_filter = set_trigger_filter,
5653 };
5654
5655 __init int register_trigger_hist_cmd(void)
5656 {
5657 int ret;
5658
5659 ret = register_event_command(&trigger_hist_cmd);
5660 WARN_ON(ret < 0);
5661
5662 return ret;
5663 }
5664
5665 static void
5666 hist_enable_trigger(struct event_trigger_data *data, void *rec,
5667 struct ring_buffer_event *event)
5668 {
5669 struct enable_trigger_data *enable_data = data->private_data;
5670 struct event_trigger_data *test;
5671
5672 list_for_each_entry_rcu(test, &enable_data->file->triggers, list) {
5673 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) {
5674 if (enable_data->enable)
5675 test->paused = false;
5676 else
5677 test->paused = true;
5678 }
5679 }
5680 }
5681
5682 static void
5683 hist_enable_count_trigger(struct event_trigger_data *data, void *rec,
5684 struct ring_buffer_event *event)
5685 {
5686 if (!data->count)
5687 return;
5688
5689 if (data->count != -1)
5690 (data->count)--;
5691
5692 hist_enable_trigger(data, rec, event);
5693 }
5694
5695 static struct event_trigger_ops hist_enable_trigger_ops = {
5696 .func = hist_enable_trigger,
5697 .print = event_enable_trigger_print,
5698 .init = event_trigger_init,
5699 .free = event_enable_trigger_free,
5700 };
5701
5702 static struct event_trigger_ops hist_enable_count_trigger_ops = {
5703 .func = hist_enable_count_trigger,
5704 .print = event_enable_trigger_print,
5705 .init = event_trigger_init,
5706 .free = event_enable_trigger_free,
5707 };
5708
5709 static struct event_trigger_ops hist_disable_trigger_ops = {
5710 .func = hist_enable_trigger,
5711 .print = event_enable_trigger_print,
5712 .init = event_trigger_init,
5713 .free = event_enable_trigger_free,
5714 };
5715
5716 static struct event_trigger_ops hist_disable_count_trigger_ops = {
5717 .func = hist_enable_count_trigger,
5718 .print = event_enable_trigger_print,
5719 .init = event_trigger_init,
5720 .free = event_enable_trigger_free,
5721 };
5722
5723 static struct event_trigger_ops *
5724 hist_enable_get_trigger_ops(char *cmd, char *param)
5725 {
5726 struct event_trigger_ops *ops;
5727 bool enable;
5728
5729 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0);
5730
5731 if (enable)
5732 ops = param ? &hist_enable_count_trigger_ops :
5733 &hist_enable_trigger_ops;
5734 else
5735 ops = param ? &hist_disable_count_trigger_ops :
5736 &hist_disable_trigger_ops;
5737
5738 return ops;
5739 }
5740
5741 static void hist_enable_unreg_all(struct trace_event_file *file)
5742 {
5743 struct event_trigger_data *test, *n;
5744
5745 list_for_each_entry_safe(test, n, &file->triggers, list) {
5746 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) {
5747 list_del_rcu(&test->list);
5748 update_cond_flag(file);
5749 trace_event_trigger_enable_disable(file, 0);
5750 if (test->ops->free)
5751 test->ops->free(test->ops, test);
5752 }
5753 }
5754 }
5755
5756 static struct event_command trigger_hist_enable_cmd = {
5757 .name = ENABLE_HIST_STR,
5758 .trigger_type = ETT_HIST_ENABLE,
5759 .func = event_enable_trigger_func,
5760 .reg = event_enable_register_trigger,
5761 .unreg = event_enable_unregister_trigger,
5762 .unreg_all = hist_enable_unreg_all,
5763 .get_trigger_ops = hist_enable_get_trigger_ops,
5764 .set_filter = set_trigger_filter,
5765 };
5766
5767 static struct event_command trigger_hist_disable_cmd = {
5768 .name = DISABLE_HIST_STR,
5769 .trigger_type = ETT_HIST_ENABLE,
5770 .func = event_enable_trigger_func,
5771 .reg = event_enable_register_trigger,
5772 .unreg = event_enable_unregister_trigger,
5773 .unreg_all = hist_enable_unreg_all,
5774 .get_trigger_ops = hist_enable_get_trigger_ops,
5775 .set_filter = set_trigger_filter,
5776 };
5777
5778 static __init void unregister_trigger_hist_enable_disable_cmds(void)
5779 {
5780 unregister_event_command(&trigger_hist_enable_cmd);
5781 unregister_event_command(&trigger_hist_disable_cmd);
5782 }
5783
5784 __init int register_trigger_hist_enable_disable_cmds(void)
5785 {
5786 int ret;
5787
5788 ret = register_event_command(&trigger_hist_enable_cmd);
5789 if (WARN_ON(ret < 0))
5790 return ret;
5791 ret = register_event_command(&trigger_hist_disable_cmd);
5792 if (WARN_ON(ret < 0))
5793 unregister_trigger_hist_enable_disable_cmds();
5794
5795 return ret;
5796 }
5797
5798 static __init int trace_events_hist_init(void)
5799 {
5800 struct dentry *entry = NULL;
5801 struct dentry *d_tracer;
5802 int err = 0;
5803
5804 d_tracer = tracing_init_dentry();
5805 if (IS_ERR(d_tracer)) {
5806 err = PTR_ERR(d_tracer);
5807 goto err;
5808 }
5809
5810 entry = tracefs_create_file("synthetic_events", 0644, d_tracer,
5811 NULL, &synth_events_fops);
5812 if (!entry) {
5813 err = -ENODEV;
5814 goto err;
5815 }
5816
5817 return err;
5818 err:
5819 pr_warn("Could not create tracefs 'synthetic_events' entry\n");
5820
5821 return err;
5822 }
5823
5824 fs_initcall(trace_events_hist_init);
Linux with added FPC-III support