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17#include <linux/stop_machine.h>
18#include <linux/clocksource.h>
19#include <linux/sched/task.h>
20#include <linux/kallsyms.h>
21#include <linux/seq_file.h>
22#include <linux/tracefs.h>
23#include <linux/hardirq.h>
24#include <linux/kthread.h>
25#include <linux/uaccess.h>
26#include <linux/bsearch.h>
27#include <linux/module.h>
28#include <linux/ftrace.h>
29#include <linux/sysctl.h>
30#include <linux/slab.h>
31#include <linux/ctype.h>
32#include <linux/sort.h>
33#include <linux/list.h>
34#include <linux/hash.h>
35#include <linux/rcupdate.h>
36#include <linux/kprobes.h>
37
38#include <trace/events/sched.h>
39
40#include <asm/sections.h>
41#include <asm/setup.h>
42
43#include "ftrace_internal.h"
44#include "trace_output.h"
45#include "trace_stat.h"
46
47#define FTRACE_WARN_ON(cond) \
48 ({ \
49 int ___r = cond; \
50 if (WARN_ON(___r)) \
51 ftrace_kill(); \
52 ___r; \
53 })
54
55#define FTRACE_WARN_ON_ONCE(cond) \
56 ({ \
57 int ___r = cond; \
58 if (WARN_ON_ONCE(___r)) \
59 ftrace_kill(); \
60 ___r; \
61 })
62
63
64#define FTRACE_HASH_BITS 7
65#define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS)
66#define FTRACE_HASH_DEFAULT_BITS 10
67#define FTRACE_HASH_MAX_BITS 12
68
69#ifdef CONFIG_DYNAMIC_FTRACE
70#define INIT_OPS_HASH(opsname) \
71 .func_hash = &opsname.local_hash, \
72 .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock),
73#define ASSIGN_OPS_HASH(opsname, val) \
74 .func_hash = val, \
75 .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock),
76#else
77#define INIT_OPS_HASH(opsname)
78#define ASSIGN_OPS_HASH(opsname, val)
79#endif
80
81enum {
82 FTRACE_MODIFY_ENABLE_FL = (1 << 0),
83 FTRACE_MODIFY_MAY_SLEEP_FL = (1 << 1),
84};
85
86struct ftrace_ops ftrace_list_end __read_mostly = {
87 .func = ftrace_stub,
88 .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_STUB,
89 INIT_OPS_HASH(ftrace_list_end)
90};
91
92
93int ftrace_enabled __read_mostly;
94static int last_ftrace_enabled;
95
96
97struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end;
98
99static struct ftrace_ops *set_function_trace_op;
100
101static bool ftrace_pids_enabled(struct ftrace_ops *ops)
102{
103 struct trace_array *tr;
104
105 if (!(ops->flags & FTRACE_OPS_FL_PID) || !ops->private)
106 return false;
107
108 tr = ops->private;
109
110 return tr->function_pids != NULL;
111}
112
113static void ftrace_update_trampoline(struct ftrace_ops *ops);
114
115
116
117
118
119static int ftrace_disabled __read_mostly;
120
121DEFINE_MUTEX(ftrace_lock);
122
123struct ftrace_ops __rcu *ftrace_ops_list __read_mostly = &ftrace_list_end;
124ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
125struct ftrace_ops global_ops;
126
127#if ARCH_SUPPORTS_FTRACE_OPS
128static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
129 struct ftrace_ops *op, struct pt_regs *regs);
130#else
131
132static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip);
133#define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops)
134#endif
135
136static inline void ftrace_ops_init(struct ftrace_ops *ops)
137{
138#ifdef CONFIG_DYNAMIC_FTRACE
139 if (!(ops->flags & FTRACE_OPS_FL_INITIALIZED)) {
140 mutex_init(&ops->local_hash.regex_lock);
141 ops->func_hash = &ops->local_hash;
142 ops->flags |= FTRACE_OPS_FL_INITIALIZED;
143 }
144#endif
145}
146
147static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip,
148 struct ftrace_ops *op, struct pt_regs *regs)
149{
150 struct trace_array *tr = op->private;
151
152 if (tr && this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid))
153 return;
154
155 op->saved_func(ip, parent_ip, op, regs);
156}
157
158static void ftrace_sync(struct work_struct *work)
159{
160
161
162
163
164
165
166
167}
168
169static void ftrace_sync_ipi(void *data)
170{
171
172 smp_rmb();
173}
174
175static ftrace_func_t ftrace_ops_get_list_func(struct ftrace_ops *ops)
176{
177
178
179
180
181 if (ops->flags & (FTRACE_OPS_FL_DYNAMIC | FTRACE_OPS_FL_RCU) ||
182 FTRACE_FORCE_LIST_FUNC)
183 return ftrace_ops_list_func;
184
185 return ftrace_ops_get_func(ops);
186}
187
188static void update_ftrace_function(void)
189{
190 ftrace_func_t func;
191
192
193
194
195
196
197 set_function_trace_op = rcu_dereference_protected(ftrace_ops_list,
198 lockdep_is_held(&ftrace_lock));
199
200
201 if (set_function_trace_op == &ftrace_list_end) {
202 func = ftrace_stub;
203
204
205
206
207
208
209 } else if (rcu_dereference_protected(ftrace_ops_list->next,
210 lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) {
211 func = ftrace_ops_get_list_func(ftrace_ops_list);
212
213 } else {
214
215 set_function_trace_op = &ftrace_list_end;
216 func = ftrace_ops_list_func;
217 }
218
219 update_function_graph_func();
220
221
222 if (ftrace_trace_function == func)
223 return;
224
225
226
227
228
229 if (func == ftrace_ops_list_func) {
230 ftrace_trace_function = func;
231
232
233
234
235 return;
236 }
237
238#ifndef CONFIG_DYNAMIC_FTRACE
239
240
241
242
243
244
245
246
247
248
249 ftrace_trace_function = ftrace_ops_list_func;
250
251
252
253
254 schedule_on_each_cpu(ftrace_sync);
255
256 function_trace_op = set_function_trace_op;
257
258 smp_wmb();
259
260 smp_call_function(ftrace_sync_ipi, NULL, 1);
261
262#endif
263
264 ftrace_trace_function = func;
265}
266
267static void add_ftrace_ops(struct ftrace_ops __rcu **list,
268 struct ftrace_ops *ops)
269{
270 rcu_assign_pointer(ops->next, *list);
271
272
273
274
275
276
277
278 rcu_assign_pointer(*list, ops);
279}
280
281static int remove_ftrace_ops(struct ftrace_ops __rcu **list,
282 struct ftrace_ops *ops)
283{
284 struct ftrace_ops **p;
285
286
287
288
289
290 if (rcu_dereference_protected(*list,
291 lockdep_is_held(&ftrace_lock)) == ops &&
292 rcu_dereference_protected(ops->next,
293 lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) {
294 *list = &ftrace_list_end;
295 return 0;
296 }
297
298 for (p = list; *p != &ftrace_list_end; p = &(*p)->next)
299 if (*p == ops)
300 break;
301
302 if (*p != ops)
303 return -1;
304
305 *p = (*p)->next;
306 return 0;
307}
308
309static void ftrace_update_trampoline(struct ftrace_ops *ops);
310
311int __register_ftrace_function(struct ftrace_ops *ops)
312{
313 if (ops->flags & FTRACE_OPS_FL_DELETED)
314 return -EINVAL;
315
316 if (WARN_ON(ops->flags & FTRACE_OPS_FL_ENABLED))
317 return -EBUSY;
318
319#ifndef CONFIG_DYNAMIC_FTRACE_WITH_REGS
320
321
322
323
324
325 if (ops->flags & FTRACE_OPS_FL_SAVE_REGS &&
326 !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED))
327 return -EINVAL;
328
329 if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)
330 ops->flags |= FTRACE_OPS_FL_SAVE_REGS;
331#endif
332
333 if (!core_kernel_data((unsigned long)ops))
334 ops->flags |= FTRACE_OPS_FL_DYNAMIC;
335
336 add_ftrace_ops(&ftrace_ops_list, ops);
337
338
339 ops->saved_func = ops->func;
340
341 if (ftrace_pids_enabled(ops))
342 ops->func = ftrace_pid_func;
343
344 ftrace_update_trampoline(ops);
345
346 if (ftrace_enabled)
347 update_ftrace_function();
348
349 return 0;
350}
351
352int __unregister_ftrace_function(struct ftrace_ops *ops)
353{
354 int ret;
355
356 if (WARN_ON(!(ops->flags & FTRACE_OPS_FL_ENABLED)))
357 return -EBUSY;
358
359 ret = remove_ftrace_ops(&ftrace_ops_list, ops);
360
361 if (ret < 0)
362 return ret;
363
364 if (ftrace_enabled)
365 update_ftrace_function();
366
367 ops->func = ops->saved_func;
368
369 return 0;
370}
371
372static void ftrace_update_pid_func(void)
373{
374 struct ftrace_ops *op;
375
376
377 if (ftrace_trace_function == ftrace_stub)
378 return;
379
380 do_for_each_ftrace_op(op, ftrace_ops_list) {
381 if (op->flags & FTRACE_OPS_FL_PID) {
382 op->func = ftrace_pids_enabled(op) ?
383 ftrace_pid_func : op->saved_func;
384 ftrace_update_trampoline(op);
385 }
386 } while_for_each_ftrace_op(op);
387
388 update_ftrace_function();
389}
390
391#ifdef CONFIG_FUNCTION_PROFILER
392struct ftrace_profile {
393 struct hlist_node node;
394 unsigned long ip;
395 unsigned long counter;
396#ifdef CONFIG_FUNCTION_GRAPH_TRACER
397 unsigned long long time;
398 unsigned long long time_squared;
399#endif
400};
401
402struct ftrace_profile_page {
403 struct ftrace_profile_page *next;
404 unsigned long index;
405 struct ftrace_profile records[];
406};
407
408struct ftrace_profile_stat {
409 atomic_t disabled;
410 struct hlist_head *hash;
411 struct ftrace_profile_page *pages;
412 struct ftrace_profile_page *start;
413 struct tracer_stat stat;
414};
415
416#define PROFILE_RECORDS_SIZE \
417 (PAGE_SIZE - offsetof(struct ftrace_profile_page, records))
418
419#define PROFILES_PER_PAGE \
420 (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile))
421
422static int ftrace_profile_enabled __read_mostly;
423
424
425static DEFINE_MUTEX(ftrace_profile_lock);
426
427static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats);
428
429#define FTRACE_PROFILE_HASH_BITS 10
430#define FTRACE_PROFILE_HASH_SIZE (1 << FTRACE_PROFILE_HASH_BITS)
431
432static void *
433function_stat_next(void *v, int idx)
434{
435 struct ftrace_profile *rec = v;
436 struct ftrace_profile_page *pg;
437
438 pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK);
439
440 again:
441 if (idx != 0)
442 rec++;
443
444 if ((void *)rec >= (void *)&pg->records[pg->index]) {
445 pg = pg->next;
446 if (!pg)
447 return NULL;
448 rec = &pg->records[0];
449 if (!rec->counter)
450 goto again;
451 }
452
453 return rec;
454}
455
456static void *function_stat_start(struct tracer_stat *trace)
457{
458 struct ftrace_profile_stat *stat =
459 container_of(trace, struct ftrace_profile_stat, stat);
460
461 if (!stat || !stat->start)
462 return NULL;
463
464 return function_stat_next(&stat->start->records[0], 0);
465}
466
467#ifdef CONFIG_FUNCTION_GRAPH_TRACER
468
469static int function_stat_cmp(void *p1, void *p2)
470{
471 struct ftrace_profile *a = p1;
472 struct ftrace_profile *b = p2;
473
474 if (a->time < b->time)
475 return -1;
476 if (a->time > b->time)
477 return 1;
478 else
479 return 0;
480}
481#else
482
483static int function_stat_cmp(void *p1, void *p2)
484{
485 struct ftrace_profile *a = p1;
486 struct ftrace_profile *b = p2;
487
488 if (a->counter < b->counter)
489 return -1;
490 if (a->counter > b->counter)
491 return 1;
492 else
493 return 0;
494}
495#endif
496
497static int function_stat_headers(struct seq_file *m)
498{
499#ifdef CONFIG_FUNCTION_GRAPH_TRACER
500 seq_puts(m, " Function "
501 "Hit Time Avg s^2\n"
502 " -------- "
503 "--- ---- --- ---\n");
504#else
505 seq_puts(m, " Function Hit\n"
506 " -------- ---\n");
507#endif
508 return 0;
509}
510
511static int function_stat_show(struct seq_file *m, void *v)
512{
513 struct ftrace_profile *rec = v;
514 char str[KSYM_SYMBOL_LEN];
515 int ret = 0;
516#ifdef CONFIG_FUNCTION_GRAPH_TRACER
517 static struct trace_seq s;
518 unsigned long long avg;
519 unsigned long long stddev;
520#endif
521 mutex_lock(&ftrace_profile_lock);
522
523
524 if (unlikely(rec->counter == 0)) {
525 ret = -EBUSY;
526 goto out;
527 }
528
529#ifdef CONFIG_FUNCTION_GRAPH_TRACER
530 avg = rec->time;
531 do_div(avg, rec->counter);
532 if (tracing_thresh && (avg < tracing_thresh))
533 goto out;
534#endif
535
536 kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
537 seq_printf(m, " %-30.30s %10lu", str, rec->counter);
538
539#ifdef CONFIG_FUNCTION_GRAPH_TRACER
540 seq_puts(m, " ");
541
542
543 if (rec->counter <= 1)
544 stddev = 0;
545 else {
546
547
548
549
550 stddev = rec->counter * rec->time_squared -
551 rec->time * rec->time;
552
553
554
555
556
557 do_div(stddev, rec->counter * (rec->counter - 1) * 1000);
558 }
559
560 trace_seq_init(&s);
561 trace_print_graph_duration(rec->time, &s);
562 trace_seq_puts(&s, " ");
563 trace_print_graph_duration(avg, &s);
564 trace_seq_puts(&s, " ");
565 trace_print_graph_duration(stddev, &s);
566 trace_print_seq(m, &s);
567#endif
568 seq_putc(m, '\n');
569out:
570 mutex_unlock(&ftrace_profile_lock);
571
572 return ret;
573}
574
575static void ftrace_profile_reset(struct ftrace_profile_stat *stat)
576{
577 struct ftrace_profile_page *pg;
578
579 pg = stat->pages = stat->start;
580
581 while (pg) {
582 memset(pg->records, 0, PROFILE_RECORDS_SIZE);
583 pg->index = 0;
584 pg = pg->next;
585 }
586
587 memset(stat->hash, 0,
588 FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head));
589}
590
591int ftrace_profile_pages_init(struct ftrace_profile_stat *stat)
592{
593 struct ftrace_profile_page *pg;
594 int functions;
595 int pages;
596 int i;
597
598
599 if (stat->pages)
600 return 0;
601
602 stat->pages = (void *)get_zeroed_page(GFP_KERNEL);
603 if (!stat->pages)
604 return -ENOMEM;
605
606#ifdef CONFIG_DYNAMIC_FTRACE
607 functions = ftrace_update_tot_cnt;
608#else
609
610
611
612
613
614
615
616 functions = 20000;
617#endif
618
619 pg = stat->start = stat->pages;
620
621 pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE);
622
623 for (i = 1; i < pages; i++) {
624 pg->next = (void *)get_zeroed_page(GFP_KERNEL);
625 if (!pg->next)
626 goto out_free;
627 pg = pg->next;
628 }
629
630 return 0;
631
632 out_free:
633 pg = stat->start;
634 while (pg) {
635 unsigned long tmp = (unsigned long)pg;
636
637 pg = pg->next;
638 free_page(tmp);
639 }
640
641 stat->pages = NULL;
642 stat->start = NULL;
643
644 return -ENOMEM;
645}
646
647static int ftrace_profile_init_cpu(int cpu)
648{
649 struct ftrace_profile_stat *stat;
650 int size;
651
652 stat = &per_cpu(ftrace_profile_stats, cpu);
653
654 if (stat->hash) {
655
656 ftrace_profile_reset(stat);
657 return 0;
658 }
659
660
661
662
663
664 size = FTRACE_PROFILE_HASH_SIZE;
665
666 stat->hash = kcalloc(size, sizeof(struct hlist_head), GFP_KERNEL);
667
668 if (!stat->hash)
669 return -ENOMEM;
670
671
672 if (ftrace_profile_pages_init(stat) < 0) {
673 kfree(stat->hash);
674 stat->hash = NULL;
675 return -ENOMEM;
676 }
677
678 return 0;
679}
680
681static int ftrace_profile_init(void)
682{
683 int cpu;
684 int ret = 0;
685
686 for_each_possible_cpu(cpu) {
687 ret = ftrace_profile_init_cpu(cpu);
688 if (ret)
689 break;
690 }
691
692 return ret;
693}
694
695
696static struct ftrace_profile *
697ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip)
698{
699 struct ftrace_profile *rec;
700 struct hlist_head *hhd;
701 unsigned long key;
702
703 key = hash_long(ip, FTRACE_PROFILE_HASH_BITS);
704 hhd = &stat->hash[key];
705
706 if (hlist_empty(hhd))
707 return NULL;
708
709 hlist_for_each_entry_rcu_notrace(rec, hhd, node) {
710 if (rec->ip == ip)
711 return rec;
712 }
713
714 return NULL;
715}
716
717static void ftrace_add_profile(struct ftrace_profile_stat *stat,
718 struct ftrace_profile *rec)
719{
720 unsigned long key;
721
722 key = hash_long(rec->ip, FTRACE_PROFILE_HASH_BITS);
723 hlist_add_head_rcu(&rec->node, &stat->hash[key]);
724}
725
726
727
728
729static struct ftrace_profile *
730ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip)
731{
732 struct ftrace_profile *rec = NULL;
733
734
735 if (atomic_inc_return(&stat->disabled) != 1)
736 goto out;
737
738
739
740
741
742 rec = ftrace_find_profiled_func(stat, ip);
743 if (rec)
744 goto out;
745
746 if (stat->pages->index == PROFILES_PER_PAGE) {
747 if (!stat->pages->next)
748 goto out;
749 stat->pages = stat->pages->next;
750 }
751
752 rec = &stat->pages->records[stat->pages->index++];
753 rec->ip = ip;
754 ftrace_add_profile(stat, rec);
755
756 out:
757 atomic_dec(&stat->disabled);
758
759 return rec;
760}
761
762static void
763function_profile_call(unsigned long ip, unsigned long parent_ip,
764 struct ftrace_ops *ops, struct pt_regs *regs)
765{
766 struct ftrace_profile_stat *stat;
767 struct ftrace_profile *rec;
768 unsigned long flags;
769
770 if (!ftrace_profile_enabled)
771 return;
772
773 local_irq_save(flags);
774
775 stat = this_cpu_ptr(&ftrace_profile_stats);
776 if (!stat->hash || !ftrace_profile_enabled)
777 goto out;
778
779 rec = ftrace_find_profiled_func(stat, ip);
780 if (!rec) {
781 rec = ftrace_profile_alloc(stat, ip);
782 if (!rec)
783 goto out;
784 }
785
786 rec->counter++;
787 out:
788 local_irq_restore(flags);
789}
790
791#ifdef CONFIG_FUNCTION_GRAPH_TRACER
792static bool fgraph_graph_time = true;
793
794void ftrace_graph_graph_time_control(bool enable)
795{
796 fgraph_graph_time = enable;
797}
798
799static int profile_graph_entry(struct ftrace_graph_ent *trace)
800{
801 struct ftrace_ret_stack *ret_stack;
802
803 function_profile_call(trace->func, 0, NULL, NULL);
804
805
806 if (!current->ret_stack)
807 return 0;
808
809 ret_stack = ftrace_graph_get_ret_stack(current, 0);
810 if (ret_stack)
811 ret_stack->subtime = 0;
812
813 return 1;
814}
815
816static void profile_graph_return(struct ftrace_graph_ret *trace)
817{
818 struct ftrace_ret_stack *ret_stack;
819 struct ftrace_profile_stat *stat;
820 unsigned long long calltime;
821 struct ftrace_profile *rec;
822 unsigned long flags;
823
824 local_irq_save(flags);
825 stat = this_cpu_ptr(&ftrace_profile_stats);
826 if (!stat->hash || !ftrace_profile_enabled)
827 goto out;
828
829
830 if (!trace->calltime)
831 goto out;
832
833 calltime = trace->rettime - trace->calltime;
834
835 if (!fgraph_graph_time) {
836
837
838 ret_stack = ftrace_graph_get_ret_stack(current, 1);
839 if (ret_stack)
840 ret_stack->subtime += calltime;
841
842 ret_stack = ftrace_graph_get_ret_stack(current, 0);
843 if (ret_stack && ret_stack->subtime < calltime)
844 calltime -= ret_stack->subtime;
845 else
846 calltime = 0;
847 }
848
849 rec = ftrace_find_profiled_func(stat, trace->func);
850 if (rec) {
851 rec->time += calltime;
852 rec->time_squared += calltime * calltime;
853 }
854
855 out:
856 local_irq_restore(flags);
857}
858
859static struct fgraph_ops fprofiler_ops = {
860 .entryfunc = &profile_graph_entry,
861 .retfunc = &profile_graph_return,
862};
863
864static int register_ftrace_profiler(void)
865{
866 return register_ftrace_graph(&fprofiler_ops);
867}
868
869static void unregister_ftrace_profiler(void)
870{
871 unregister_ftrace_graph(&fprofiler_ops);
872}
873#else
874static struct ftrace_ops ftrace_profile_ops __read_mostly = {
875 .func = function_profile_call,
876 .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_INITIALIZED,
877 INIT_OPS_HASH(ftrace_profile_ops)
878};
879
880static int register_ftrace_profiler(void)
881{
882 return register_ftrace_function(&ftrace_profile_ops);
883}
884
885static void unregister_ftrace_profiler(void)
886{
887 unregister_ftrace_function(&ftrace_profile_ops);
888}
889#endif
890
891static ssize_t
892ftrace_profile_write(struct file *filp, const char __user *ubuf,
893 size_t cnt, loff_t *ppos)
894{
895 unsigned long val;
896 int ret;
897
898 ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
899 if (ret)
900 return ret;
901
902 val = !!val;
903
904 mutex_lock(&ftrace_profile_lock);
905 if (ftrace_profile_enabled ^ val) {
906 if (val) {
907 ret = ftrace_profile_init();
908 if (ret < 0) {
909 cnt = ret;
910 goto out;
911 }
912
913 ret = register_ftrace_profiler();
914 if (ret < 0) {
915 cnt = ret;
916 goto out;
917 }
918 ftrace_profile_enabled = 1;
919 } else {
920 ftrace_profile_enabled = 0;
921
922
923
924
925 unregister_ftrace_profiler();
926 }
927 }
928 out:
929 mutex_unlock(&ftrace_profile_lock);
930
931 *ppos += cnt;
932
933 return cnt;
934}
935
936static ssize_t
937ftrace_profile_read(struct file *filp, char __user *ubuf,
938 size_t cnt, loff_t *ppos)
939{
940 char buf[64];
941 int r;
942
943 r = sprintf(buf, "%u\n", ftrace_profile_enabled);
944 return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
945}
946
947static const struct file_operations ftrace_profile_fops = {
948 .open = tracing_open_generic,
949 .read = ftrace_profile_read,
950 .write = ftrace_profile_write,
951 .llseek = default_llseek,
952};
953
954
955static struct tracer_stat function_stats __initdata = {
956 .name = "functions",
957 .stat_start = function_stat_start,
958 .stat_next = function_stat_next,
959 .stat_cmp = function_stat_cmp,
960 .stat_headers = function_stat_headers,
961 .stat_show = function_stat_show
962};
963
964static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
965{
966 struct ftrace_profile_stat *stat;
967 struct dentry *entry;
968 char *name;
969 int ret;
970 int cpu;
971
972 for_each_possible_cpu(cpu) {
973 stat = &per_cpu(ftrace_profile_stats, cpu);
974
975 name = kasprintf(GFP_KERNEL, "function%d", cpu);
976 if (!name) {
977
978
979
980
981 WARN(1,
982 "Could not allocate stat file for cpu %d\n",
983 cpu);
984 return;
985 }
986 stat->stat = function_stats;
987 stat->stat.name = name;
988 ret = register_stat_tracer(&stat->stat);
989 if (ret) {
990 WARN(1,
991 "Could not register function stat for cpu %d\n",
992 cpu);
993 kfree(name);
994 return;
995 }
996 }
997
998 entry = tracefs_create_file("function_profile_enabled", 0644,
999 d_tracer, NULL, &ftrace_profile_fops);
1000 if (!entry)
1001 pr_warn("Could not create tracefs 'function_profile_enabled' entry\n");
1002}
1003
1004#else
1005static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
1006{
1007}
1008#endif
1009
1010#ifdef CONFIG_DYNAMIC_FTRACE
1011
1012static struct ftrace_ops *removed_ops;
1013
1014
1015
1016
1017
1018static bool update_all_ops;
1019
1020#ifndef CONFIG_FTRACE_MCOUNT_RECORD
1021# error Dynamic ftrace depends on MCOUNT_RECORD
1022#endif
1023
1024struct ftrace_func_entry {
1025 struct hlist_node hlist;
1026 unsigned long ip;
1027};
1028
1029struct ftrace_func_probe {
1030 struct ftrace_probe_ops *probe_ops;
1031 struct ftrace_ops ops;
1032 struct trace_array *tr;
1033 struct list_head list;
1034 void *data;
1035 int ref;
1036};
1037
1038
1039
1040
1041
1042
1043
1044static const struct hlist_head empty_buckets[1];
1045static const struct ftrace_hash empty_hash = {
1046 .buckets = (struct hlist_head *)empty_buckets,
1047};
1048#define EMPTY_HASH ((struct ftrace_hash *)&empty_hash)
1049
1050struct ftrace_ops global_ops = {
1051 .func = ftrace_stub,
1052 .local_hash.notrace_hash = EMPTY_HASH,
1053 .local_hash.filter_hash = EMPTY_HASH,
1054 INIT_OPS_HASH(global_ops)
1055 .flags = FTRACE_OPS_FL_RECURSION_SAFE |
1056 FTRACE_OPS_FL_INITIALIZED |
1057 FTRACE_OPS_FL_PID,
1058};
1059
1060
1061
1062
1063struct ftrace_ops *ftrace_ops_trampoline(unsigned long addr)
1064{
1065 struct ftrace_ops *op = NULL;
1066
1067
1068
1069
1070
1071 preempt_disable_notrace();
1072
1073 do_for_each_ftrace_op(op, ftrace_ops_list) {
1074
1075
1076
1077
1078
1079 if (op->trampoline && op->trampoline_size)
1080 if (addr >= op->trampoline &&
1081 addr < op->trampoline + op->trampoline_size) {
1082 preempt_enable_notrace();
1083 return op;
1084 }
1085 } while_for_each_ftrace_op(op);
1086 preempt_enable_notrace();
1087
1088 return NULL;
1089}
1090
1091
1092
1093
1094
1095
1096
1097bool is_ftrace_trampoline(unsigned long addr)
1098{
1099 return ftrace_ops_trampoline(addr) != NULL;
1100}
1101
1102struct ftrace_page {
1103 struct ftrace_page *next;
1104 struct dyn_ftrace *records;
1105 int index;
1106 int size;
1107};
1108
1109#define ENTRY_SIZE sizeof(struct dyn_ftrace)
1110#define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE)
1111
1112
1113#define NR_TO_INIT 10000
1114
1115static struct ftrace_page *ftrace_pages_start;
1116static struct ftrace_page *ftrace_pages;
1117
1118static __always_inline unsigned long
1119ftrace_hash_key(struct ftrace_hash *hash, unsigned long ip)
1120{
1121 if (hash->size_bits > 0)
1122 return hash_long(ip, hash->size_bits);
1123
1124 return 0;
1125}
1126
1127
1128static __always_inline struct ftrace_func_entry *
1129__ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip)
1130{
1131 unsigned long key;
1132 struct ftrace_func_entry *entry;
1133 struct hlist_head *hhd;
1134
1135 key = ftrace_hash_key(hash, ip);
1136 hhd = &hash->buckets[key];
1137
1138 hlist_for_each_entry_rcu_notrace(entry, hhd, hlist) {
1139 if (entry->ip == ip)
1140 return entry;
1141 }
1142 return NULL;
1143}
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155struct ftrace_func_entry *
1156ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip)
1157{
1158 if (ftrace_hash_empty(hash))
1159 return NULL;
1160
1161 return __ftrace_lookup_ip(hash, ip);
1162}
1163
1164static void __add_hash_entry(struct ftrace_hash *hash,
1165 struct ftrace_func_entry *entry)
1166{
1167 struct hlist_head *hhd;
1168 unsigned long key;
1169
1170 key = ftrace_hash_key(hash, entry->ip);
1171 hhd = &hash->buckets[key];
1172 hlist_add_head(&entry->hlist, hhd);
1173 hash->count++;
1174}
1175
1176static int add_hash_entry(struct ftrace_hash *hash, unsigned long ip)
1177{
1178 struct ftrace_func_entry *entry;
1179
1180 entry = kmalloc(sizeof(*entry), GFP_KERNEL);
1181 if (!entry)
1182 return -ENOMEM;
1183
1184 entry->ip = ip;
1185 __add_hash_entry(hash, entry);
1186
1187 return 0;
1188}
1189
1190static void
1191free_hash_entry(struct ftrace_hash *hash,
1192 struct ftrace_func_entry *entry)
1193{
1194 hlist_del(&entry->hlist);
1195 kfree(entry);
1196 hash->count--;
1197}
1198
1199static void
1200remove_hash_entry(struct ftrace_hash *hash,
1201 struct ftrace_func_entry *entry)
1202{
1203 hlist_del_rcu(&entry->hlist);
1204 hash->count--;
1205}
1206
1207static void ftrace_hash_clear(struct ftrace_hash *hash)
1208{
1209 struct hlist_head *hhd;
1210 struct hlist_node *tn;
1211 struct ftrace_func_entry *entry;
1212 int size = 1 << hash->size_bits;
1213 int i;
1214
1215 if (!hash->count)
1216 return;
1217
1218 for (i = 0; i < size; i++) {
1219 hhd = &hash->buckets[i];
1220 hlist_for_each_entry_safe(entry, tn, hhd, hlist)
1221 free_hash_entry(hash, entry);
1222 }
1223 FTRACE_WARN_ON(hash->count);
1224}
1225
1226static void free_ftrace_mod(struct ftrace_mod_load *ftrace_mod)
1227{
1228 list_del(&ftrace_mod->list);
1229 kfree(ftrace_mod->module);
1230 kfree(ftrace_mod->func);
1231 kfree(ftrace_mod);
1232}
1233
1234static void clear_ftrace_mod_list(struct list_head *head)
1235{
1236 struct ftrace_mod_load *p, *n;
1237
1238
1239 if (!head)
1240 return;
1241
1242 mutex_lock(&ftrace_lock);
1243 list_for_each_entry_safe(p, n, head, list)
1244 free_ftrace_mod(p);
1245 mutex_unlock(&ftrace_lock);
1246}
1247
1248static void free_ftrace_hash(struct ftrace_hash *hash)
1249{
1250 if (!hash || hash == EMPTY_HASH)
1251 return;
1252 ftrace_hash_clear(hash);
1253 kfree(hash->buckets);
1254 kfree(hash);
1255}
1256
1257static void __free_ftrace_hash_rcu(struct rcu_head *rcu)
1258{
1259 struct ftrace_hash *hash;
1260
1261 hash = container_of(rcu, struct ftrace_hash, rcu);
1262 free_ftrace_hash(hash);
1263}
1264
1265static void free_ftrace_hash_rcu(struct ftrace_hash *hash)
1266{
1267 if (!hash || hash == EMPTY_HASH)
1268 return;
1269 call_rcu(&hash->rcu, __free_ftrace_hash_rcu);
1270}
1271
1272void ftrace_free_filter(struct ftrace_ops *ops)
1273{
1274 ftrace_ops_init(ops);
1275 free_ftrace_hash(ops->func_hash->filter_hash);
1276 free_ftrace_hash(ops->func_hash->notrace_hash);
1277}
1278
1279static struct ftrace_hash *alloc_ftrace_hash(int size_bits)
1280{
1281 struct ftrace_hash *hash;
1282 int size;
1283
1284 hash = kzalloc(sizeof(*hash), GFP_KERNEL);
1285 if (!hash)
1286 return NULL;
1287
1288 size = 1 << size_bits;
1289 hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL);
1290
1291 if (!hash->buckets) {
1292 kfree(hash);
1293 return NULL;
1294 }
1295
1296 hash->size_bits = size_bits;
1297
1298 return hash;
1299}
1300
1301
1302static int ftrace_add_mod(struct trace_array *tr,
1303 const char *func, const char *module,
1304 int enable)
1305{
1306 struct ftrace_mod_load *ftrace_mod;
1307 struct list_head *mod_head = enable ? &tr->mod_trace : &tr->mod_notrace;
1308
1309 ftrace_mod = kzalloc(sizeof(*ftrace_mod), GFP_KERNEL);
1310 if (!ftrace_mod)
1311 return -ENOMEM;
1312
1313 ftrace_mod->func = kstrdup(func, GFP_KERNEL);
1314 ftrace_mod->module = kstrdup(module, GFP_KERNEL);
1315 ftrace_mod->enable = enable;
1316
1317 if (!ftrace_mod->func || !ftrace_mod->module)
1318 goto out_free;
1319
1320 list_add(&ftrace_mod->list, mod_head);
1321
1322 return 0;
1323
1324 out_free:
1325 free_ftrace_mod(ftrace_mod);
1326
1327 return -ENOMEM;
1328}
1329
1330static struct ftrace_hash *
1331alloc_and_copy_ftrace_hash(int size_bits, struct ftrace_hash *hash)
1332{
1333 struct ftrace_func_entry *entry;
1334 struct ftrace_hash *new_hash;
1335 int size;
1336 int ret;
1337 int i;
1338
1339 new_hash = alloc_ftrace_hash(size_bits);
1340 if (!new_hash)
1341 return NULL;
1342
1343 if (hash)
1344 new_hash->flags = hash->flags;
1345
1346
1347 if (ftrace_hash_empty(hash))
1348 return new_hash;
1349
1350 size = 1 << hash->size_bits;
1351 for (i = 0; i < size; i++) {
1352 hlist_for_each_entry(entry, &hash->buckets[i], hlist) {
1353 ret = add_hash_entry(new_hash, entry->ip);
1354 if (ret < 0)
1355 goto free_hash;
1356 }
1357 }
1358
1359 FTRACE_WARN_ON(new_hash->count != hash->count);
1360
1361 return new_hash;
1362
1363 free_hash:
1364 free_ftrace_hash(new_hash);
1365 return NULL;
1366}
1367
1368static void
1369ftrace_hash_rec_disable_modify(struct ftrace_ops *ops, int filter_hash);
1370static void
1371ftrace_hash_rec_enable_modify(struct ftrace_ops *ops, int filter_hash);
1372
1373static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops,
1374 struct ftrace_hash *new_hash);
1375
1376static struct ftrace_hash *
1377__ftrace_hash_move(struct ftrace_hash *src)
1378{
1379 struct ftrace_func_entry *entry;
1380 struct hlist_node *tn;
1381 struct hlist_head *hhd;
1382 struct ftrace_hash *new_hash;
1383 int size = src->count;
1384 int bits = 0;
1385 int i;
1386
1387
1388
1389
1390 if (ftrace_hash_empty(src))
1391 return EMPTY_HASH;
1392
1393
1394
1395
1396 for (size /= 2; size; size >>= 1)
1397 bits++;
1398
1399
1400 if (bits > FTRACE_HASH_MAX_BITS)
1401 bits = FTRACE_HASH_MAX_BITS;
1402
1403 new_hash = alloc_ftrace_hash(bits);
1404 if (!new_hash)
1405 return NULL;
1406
1407 new_hash->flags = src->flags;
1408
1409 size = 1 << src->size_bits;
1410 for (i = 0; i < size; i++) {
1411 hhd = &src->buckets[i];
1412 hlist_for_each_entry_safe(entry, tn, hhd, hlist) {
1413 remove_hash_entry(src, entry);
1414 __add_hash_entry(new_hash, entry);
1415 }
1416 }
1417
1418 return new_hash;
1419}
1420
1421static int
1422ftrace_hash_move(struct ftrace_ops *ops, int enable,
1423 struct ftrace_hash **dst, struct ftrace_hash *src)
1424{
1425 struct ftrace_hash *new_hash;
1426 int ret;
1427
1428
1429 if (ops->flags & FTRACE_OPS_FL_IPMODIFY && !enable)
1430 return -EINVAL;
1431
1432 new_hash = __ftrace_hash_move(src);
1433 if (!new_hash)
1434 return -ENOMEM;
1435
1436
1437 if (enable) {
1438
1439 ret = ftrace_hash_ipmodify_update(ops, new_hash);
1440 if (ret < 0) {
1441 free_ftrace_hash(new_hash);
1442 return ret;
1443 }
1444 }
1445
1446
1447
1448
1449
1450 ftrace_hash_rec_disable_modify(ops, enable);
1451
1452 rcu_assign_pointer(*dst, new_hash);
1453
1454 ftrace_hash_rec_enable_modify(ops, enable);
1455
1456 return 0;
1457}
1458
1459static bool hash_contains_ip(unsigned long ip,
1460 struct ftrace_ops_hash *hash)
1461{
1462
1463
1464
1465
1466
1467
1468 return (ftrace_hash_empty(hash->filter_hash) ||
1469 __ftrace_lookup_ip(hash->filter_hash, ip)) &&
1470 (ftrace_hash_empty(hash->notrace_hash) ||
1471 !__ftrace_lookup_ip(hash->notrace_hash, ip));
1472}
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486int
1487ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip, void *regs)
1488{
1489 struct ftrace_ops_hash hash;
1490 int ret;
1491
1492#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
1493
1494
1495
1496
1497
1498 if (regs == NULL && (ops->flags & FTRACE_OPS_FL_SAVE_REGS))
1499 return 0;
1500#endif
1501
1502 rcu_assign_pointer(hash.filter_hash, ops->func_hash->filter_hash);
1503 rcu_assign_pointer(hash.notrace_hash, ops->func_hash->notrace_hash);
1504
1505 if (hash_contains_ip(ip, &hash))
1506 ret = 1;
1507 else
1508 ret = 0;
1509
1510 return ret;
1511}
1512
1513
1514
1515
1516
1517#define do_for_each_ftrace_rec(pg, rec) \
1518 for (pg = ftrace_pages_start; pg; pg = pg->next) { \
1519 int _____i; \
1520 for (_____i = 0; _____i < pg->index; _____i++) { \
1521 rec = &pg->records[_____i];
1522
1523#define while_for_each_ftrace_rec() \
1524 } \
1525 }
1526
1527
1528static int ftrace_cmp_recs(const void *a, const void *b)
1529{
1530 const struct dyn_ftrace *key = a;
1531 const struct dyn_ftrace *rec = b;
1532
1533 if (key->flags < rec->ip)
1534 return -1;
1535 if (key->ip >= rec->ip + MCOUNT_INSN_SIZE)
1536 return 1;
1537 return 0;
1538}
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552unsigned long ftrace_location_range(unsigned long start, unsigned long end)
1553{
1554 struct ftrace_page *pg;
1555 struct dyn_ftrace *rec;
1556 struct dyn_ftrace key;
1557
1558 key.ip = start;
1559 key.flags = end;
1560
1561 for (pg = ftrace_pages_start; pg; pg = pg->next) {
1562 if (end < pg->records[0].ip ||
1563 start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE))
1564 continue;
1565 rec = bsearch(&key, pg->records, pg->index,
1566 sizeof(struct dyn_ftrace),
1567 ftrace_cmp_recs);
1568 if (rec)
1569 return rec->ip;
1570 }
1571
1572 return 0;
1573}
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584unsigned long ftrace_location(unsigned long ip)
1585{
1586 return ftrace_location_range(ip, ip);
1587}
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599int ftrace_text_reserved(const void *start, const void *end)
1600{
1601 unsigned long ret;
1602
1603 ret = ftrace_location_range((unsigned long)start,
1604 (unsigned long)end);
1605
1606 return (int)!!ret;
1607}
1608
1609
1610static bool test_rec_ops_needs_regs(struct dyn_ftrace *rec)
1611{
1612 struct ftrace_ops *ops;
1613 bool keep_regs = false;
1614
1615 for (ops = ftrace_ops_list;
1616 ops != &ftrace_list_end; ops = ops->next) {
1617
1618 if (ftrace_ops_test(ops, rec->ip, rec)) {
1619 if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) {
1620 keep_regs = true;
1621 break;
1622 }
1623 }
1624 }
1625
1626 return keep_regs;
1627}
1628
1629static bool __ftrace_hash_rec_update(struct ftrace_ops *ops,
1630 int filter_hash,
1631 bool inc)
1632{
1633 struct ftrace_hash *hash;
1634 struct ftrace_hash *other_hash;
1635 struct ftrace_page *pg;
1636 struct dyn_ftrace *rec;
1637 bool update = false;
1638 int count = 0;
1639 int all = false;
1640
1641
1642 if (!(ops->flags & FTRACE_OPS_FL_ENABLED))
1643 return false;
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656 if (filter_hash) {
1657 hash = ops->func_hash->filter_hash;
1658 other_hash = ops->func_hash->notrace_hash;
1659 if (ftrace_hash_empty(hash))
1660 all = true;
1661 } else {
1662 inc = !inc;
1663 hash = ops->func_hash->notrace_hash;
1664 other_hash = ops->func_hash->filter_hash;
1665
1666
1667
1668
1669 if (ftrace_hash_empty(hash))
1670 return false;
1671 }
1672
1673 do_for_each_ftrace_rec(pg, rec) {
1674 int in_other_hash = 0;
1675 int in_hash = 0;
1676 int match = 0;
1677
1678 if (rec->flags & FTRACE_FL_DISABLED)
1679 continue;
1680
1681 if (all) {
1682
1683
1684
1685
1686 if (!other_hash || !ftrace_lookup_ip(other_hash, rec->ip))
1687 match = 1;
1688 } else {
1689 in_hash = !!ftrace_lookup_ip(hash, rec->ip);
1690 in_other_hash = !!ftrace_lookup_ip(other_hash, rec->ip);
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702 if (filter_hash && in_hash && !in_other_hash)
1703 match = 1;
1704 else if (!filter_hash && in_hash &&
1705 (in_other_hash || ftrace_hash_empty(other_hash)))
1706 match = 1;
1707 }
1708 if (!match)
1709 continue;
1710
1711 if (inc) {
1712 rec->flags++;
1713 if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX))
1714 return false;
1715
1716
1717
1718
1719
1720
1721 if (ftrace_rec_count(rec) == 1 && ops->trampoline)
1722 rec->flags |= FTRACE_FL_TRAMP;
1723 else
1724
1725
1726
1727
1728
1729
1730 rec->flags &= ~FTRACE_FL_TRAMP;
1731
1732
1733
1734
1735
1736 if (ops->flags & FTRACE_OPS_FL_SAVE_REGS)
1737 rec->flags |= FTRACE_FL_REGS;
1738 } else {
1739 if (FTRACE_WARN_ON(ftrace_rec_count(rec) == 0))
1740 return false;
1741 rec->flags--;
1742
1743
1744
1745
1746
1747
1748
1749 if (ftrace_rec_count(rec) > 0 &&
1750 rec->flags & FTRACE_FL_REGS &&
1751 ops->flags & FTRACE_OPS_FL_SAVE_REGS) {
1752 if (!test_rec_ops_needs_regs(rec))
1753 rec->flags &= ~FTRACE_FL_REGS;
1754 }
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765 rec->flags &= ~FTRACE_FL_TRAMP;
1766
1767
1768
1769
1770
1771 }
1772 count++;
1773
1774
1775 update |= ftrace_test_record(rec, 1) != FTRACE_UPDATE_IGNORE;
1776
1777
1778 if (!all && count == hash->count)
1779 return update;
1780 } while_for_each_ftrace_rec();
1781
1782 return update;
1783}
1784
1785static bool ftrace_hash_rec_disable(struct ftrace_ops *ops,
1786 int filter_hash)
1787{
1788 return __ftrace_hash_rec_update(ops, filter_hash, 0);
1789}
1790
1791static bool ftrace_hash_rec_enable(struct ftrace_ops *ops,
1792 int filter_hash)
1793{
1794 return __ftrace_hash_rec_update(ops, filter_hash, 1);
1795}
1796
1797static void ftrace_hash_rec_update_modify(struct ftrace_ops *ops,
1798 int filter_hash, int inc)
1799{
1800 struct ftrace_ops *op;
1801
1802 __ftrace_hash_rec_update(ops, filter_hash, inc);
1803
1804 if (ops->func_hash != &global_ops.local_hash)
1805 return;
1806
1807
1808
1809
1810
1811 do_for_each_ftrace_op(op, ftrace_ops_list) {
1812
1813 if (op == ops)
1814 continue;
1815 if (op->func_hash == &global_ops.local_hash)
1816 __ftrace_hash_rec_update(op, filter_hash, inc);
1817 } while_for_each_ftrace_op(op);
1818}
1819
1820static void ftrace_hash_rec_disable_modify(struct ftrace_ops *ops,
1821 int filter_hash)
1822{
1823 ftrace_hash_rec_update_modify(ops, filter_hash, 0);
1824}
1825
1826static void ftrace_hash_rec_enable_modify(struct ftrace_ops *ops,
1827 int filter_hash)
1828{
1829 ftrace_hash_rec_update_modify(ops, filter_hash, 1);
1830}
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841static int __ftrace_hash_update_ipmodify(struct ftrace_ops *ops,
1842 struct ftrace_hash *old_hash,
1843 struct ftrace_hash *new_hash)
1844{
1845 struct ftrace_page *pg;
1846 struct dyn_ftrace *rec, *end = NULL;
1847 int in_old, in_new;
1848
1849
1850 if (!(ops->flags & FTRACE_OPS_FL_ENABLED))
1851 return 0;
1852
1853 if (!(ops->flags & FTRACE_OPS_FL_IPMODIFY))
1854 return 0;
1855
1856
1857
1858
1859
1860 if (!new_hash || !old_hash)
1861 return -EINVAL;
1862
1863
1864 do_for_each_ftrace_rec(pg, rec) {
1865
1866 if (rec->flags & FTRACE_FL_DISABLED)
1867 continue;
1868
1869
1870 in_old = !!ftrace_lookup_ip(old_hash, rec->ip);
1871 in_new = !!ftrace_lookup_ip(new_hash, rec->ip);
1872 if (in_old == in_new)
1873 continue;
1874
1875 if (in_new) {
1876
1877 if (rec->flags & FTRACE_FL_IPMODIFY)
1878 goto rollback;
1879 rec->flags |= FTRACE_FL_IPMODIFY;
1880 } else
1881 rec->flags &= ~FTRACE_FL_IPMODIFY;
1882 } while_for_each_ftrace_rec();
1883
1884 return 0;
1885
1886rollback:
1887 end = rec;
1888
1889
1890 do_for_each_ftrace_rec(pg, rec) {
1891
1892 if (rec->flags & FTRACE_FL_DISABLED)
1893 continue;
1894
1895 if (rec == end)
1896 goto err_out;
1897
1898 in_old = !!ftrace_lookup_ip(old_hash, rec->ip);
1899 in_new = !!ftrace_lookup_ip(new_hash, rec->ip);
1900 if (in_old == in_new)
1901 continue;
1902
1903 if (in_new)
1904 rec->flags &= ~FTRACE_FL_IPMODIFY;
1905 else
1906 rec->flags |= FTRACE_FL_IPMODIFY;
1907 } while_for_each_ftrace_rec();
1908
1909err_out:
1910 return -EBUSY;
1911}
1912
1913static int ftrace_hash_ipmodify_enable(struct ftrace_ops *ops)
1914{
1915 struct ftrace_hash *hash = ops->func_hash->filter_hash;
1916
1917 if (ftrace_hash_empty(hash))
1918 hash = NULL;
1919
1920 return __ftrace_hash_update_ipmodify(ops, EMPTY_HASH, hash);
1921}
1922
1923
1924static void ftrace_hash_ipmodify_disable(struct ftrace_ops *ops)
1925{
1926 struct ftrace_hash *hash = ops->func_hash->filter_hash;
1927
1928 if (ftrace_hash_empty(hash))
1929 hash = NULL;
1930
1931 __ftrace_hash_update_ipmodify(ops, hash, EMPTY_HASH);
1932}
1933
1934static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops,
1935 struct ftrace_hash *new_hash)
1936{
1937 struct ftrace_hash *old_hash = ops->func_hash->filter_hash;
1938
1939 if (ftrace_hash_empty(old_hash))
1940 old_hash = NULL;
1941
1942 if (ftrace_hash_empty(new_hash))
1943 new_hash = NULL;
1944
1945 return __ftrace_hash_update_ipmodify(ops, old_hash, new_hash);
1946}
1947
1948static void print_ip_ins(const char *fmt, const unsigned char *p)
1949{
1950 int i;
1951
1952 printk(KERN_CONT "%s", fmt);
1953
1954 for (i = 0; i < MCOUNT_INSN_SIZE; i++)
1955 printk(KERN_CONT "%s%02x", i ? ":" : "", p[i]);
1956}
1957
1958static struct ftrace_ops *
1959ftrace_find_tramp_ops_any(struct dyn_ftrace *rec);
1960static struct ftrace_ops *
1961ftrace_find_tramp_ops_next(struct dyn_ftrace *rec, struct ftrace_ops *ops);
1962
1963enum ftrace_bug_type ftrace_bug_type;
1964const void *ftrace_expected;
1965
1966static void print_bug_type(void)
1967{
1968 switch (ftrace_bug_type) {
1969 case FTRACE_BUG_UNKNOWN:
1970 break;
1971 case FTRACE_BUG_INIT:
1972 pr_info("Initializing ftrace call sites\n");
1973 break;
1974 case FTRACE_BUG_NOP:
1975 pr_info("Setting ftrace call site to NOP\n");
1976 break;
1977 case FTRACE_BUG_CALL:
1978 pr_info("Setting ftrace call site to call ftrace function\n");
1979 break;
1980 case FTRACE_BUG_UPDATE:
1981 pr_info("Updating ftrace call site to call a different ftrace function\n");
1982 break;
1983 }
1984}
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998void ftrace_bug(int failed, struct dyn_ftrace *rec)
1999{
2000 unsigned long ip = rec ? rec->ip : 0;
2001
2002 switch (failed) {
2003 case -EFAULT:
2004 FTRACE_WARN_ON_ONCE(1);
2005 pr_info("ftrace faulted on modifying ");
2006 print_ip_sym(ip);
2007 break;
2008 case -EINVAL:
2009 FTRACE_WARN_ON_ONCE(1);
2010 pr_info("ftrace failed to modify ");
2011 print_ip_sym(ip);
2012 print_ip_ins(" actual: ", (unsigned char *)ip);
2013 pr_cont("\n");
2014 if (ftrace_expected) {
2015 print_ip_ins(" expected: ", ftrace_expected);
2016 pr_cont("\n");
2017 }
2018 break;
2019 case -EPERM:
2020 FTRACE_WARN_ON_ONCE(1);
2021 pr_info("ftrace faulted on writing ");
2022 print_ip_sym(ip);
2023 break;
2024 default:
2025 FTRACE_WARN_ON_ONCE(1);
2026 pr_info("ftrace faulted on unknown error ");
2027 print_ip_sym(ip);
2028 }
2029 print_bug_type();
2030 if (rec) {
2031 struct ftrace_ops *ops = NULL;
2032
2033 pr_info("ftrace record flags: %lx\n", rec->flags);
2034 pr_cont(" (%ld)%s", ftrace_rec_count(rec),
2035 rec->flags & FTRACE_FL_REGS ? " R" : " ");
2036 if (rec->flags & FTRACE_FL_TRAMP_EN) {
2037 ops = ftrace_find_tramp_ops_any(rec);
2038 if (ops) {
2039 do {
2040 pr_cont("\ttramp: %pS (%pS)",
2041 (void *)ops->trampoline,
2042 (void *)ops->func);
2043 ops = ftrace_find_tramp_ops_next(rec, ops);
2044 } while (ops);
2045 } else
2046 pr_cont("\ttramp: ERROR!");
2047
2048 }
2049 ip = ftrace_get_addr_curr(rec);
2050 pr_cont("\n expected tramp: %lx\n", ip);
2051 }
2052}
2053
2054static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update)
2055{
2056 unsigned long flag = 0UL;
2057
2058 ftrace_bug_type = FTRACE_BUG_UNKNOWN;
2059
2060 if (rec->flags & FTRACE_FL_DISABLED)
2061 return FTRACE_UPDATE_IGNORE;
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074 if (enable && ftrace_rec_count(rec))
2075 flag = FTRACE_FL_ENABLED;
2076
2077
2078
2079
2080
2081
2082 if (flag) {
2083 if (!(rec->flags & FTRACE_FL_REGS) !=
2084 !(rec->flags & FTRACE_FL_REGS_EN))
2085 flag |= FTRACE_FL_REGS;
2086
2087 if (!(rec->flags & FTRACE_FL_TRAMP) !=
2088 !(rec->flags & FTRACE_FL_TRAMP_EN))
2089 flag |= FTRACE_FL_TRAMP;
2090 }
2091
2092
2093 if ((rec->flags & FTRACE_FL_ENABLED) == flag)
2094 return FTRACE_UPDATE_IGNORE;
2095
2096 if (flag) {
2097
2098 flag ^= rec->flags & FTRACE_FL_ENABLED;
2099
2100 if (update) {
2101 rec->flags |= FTRACE_FL_ENABLED;
2102 if (flag & FTRACE_FL_REGS) {
2103 if (rec->flags & FTRACE_FL_REGS)
2104 rec->flags |= FTRACE_FL_REGS_EN;
2105 else
2106 rec->flags &= ~FTRACE_FL_REGS_EN;
2107 }
2108 if (flag & FTRACE_FL_TRAMP) {
2109 if (rec->flags & FTRACE_FL_TRAMP)
2110 rec->flags |= FTRACE_FL_TRAMP_EN;
2111 else
2112 rec->flags &= ~FTRACE_FL_TRAMP_EN;
2113 }
2114 }
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124 if (flag & FTRACE_FL_ENABLED) {
2125 ftrace_bug_type = FTRACE_BUG_CALL;
2126 return FTRACE_UPDATE_MAKE_CALL;
2127 }
2128
2129 ftrace_bug_type = FTRACE_BUG_UPDATE;
2130 return FTRACE_UPDATE_MODIFY_CALL;
2131 }
2132
2133 if (update) {
2134
2135 if (!ftrace_rec_count(rec))
2136 rec->flags = 0;
2137 else
2138
2139
2140
2141
2142 rec->flags &= ~(FTRACE_FL_ENABLED | FTRACE_FL_TRAMP_EN |
2143 FTRACE_FL_REGS_EN);
2144 }
2145
2146 ftrace_bug_type = FTRACE_BUG_NOP;
2147 return FTRACE_UPDATE_MAKE_NOP;
2148}
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158int ftrace_update_record(struct dyn_ftrace *rec, int enable)
2159{
2160 return ftrace_check_record(rec, enable, 1);
2161}
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172int ftrace_test_record(struct dyn_ftrace *rec, int enable)
2173{
2174 return ftrace_check_record(rec, enable, 0);
2175}
2176
2177static struct ftrace_ops *
2178ftrace_find_tramp_ops_any(struct dyn_ftrace *rec)
2179{
2180 struct ftrace_ops *op;
2181 unsigned long ip = rec->ip;
2182
2183 do_for_each_ftrace_op(op, ftrace_ops_list) {
2184
2185 if (!op->trampoline)
2186 continue;
2187
2188 if (hash_contains_ip(ip, op->func_hash))
2189 return op;
2190 } while_for_each_ftrace_op(op);
2191
2192 return NULL;
2193}
2194
2195static struct ftrace_ops *
2196ftrace_find_tramp_ops_next(struct dyn_ftrace *rec,
2197 struct ftrace_ops *op)
2198{
2199 unsigned long ip = rec->ip;
2200
2201 while_for_each_ftrace_op(op) {
2202
2203 if (!op->trampoline)
2204 continue;
2205
2206 if (hash_contains_ip(ip, op->func_hash))
2207 return op;
2208 }
2209
2210 return NULL;
2211}
2212
2213static struct ftrace_ops *
2214ftrace_find_tramp_ops_curr(struct dyn_ftrace *rec)
2215{
2216 struct ftrace_ops *op;
2217 unsigned long ip = rec->ip;
2218
2219
2220
2221
2222
2223
2224
2225 if (removed_ops) {
2226 if (hash_contains_ip(ip, &removed_ops->old_hash))
2227 return removed_ops;
2228 }
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248 do_for_each_ftrace_op(op, ftrace_ops_list) {
2249
2250 if (!op->trampoline)
2251 continue;
2252
2253
2254
2255
2256
2257 if (op->flags & FTRACE_OPS_FL_ADDING)
2258 continue;
2259
2260
2261
2262
2263
2264
2265
2266 if ((op->flags & FTRACE_OPS_FL_MODIFYING) &&
2267 hash_contains_ip(ip, &op->old_hash))
2268 return op;
2269
2270
2271
2272
2273
2274 if (!(op->flags & FTRACE_OPS_FL_MODIFYING) &&
2275 hash_contains_ip(ip, op->func_hash))
2276 return op;
2277
2278 } while_for_each_ftrace_op(op);
2279
2280 return NULL;
2281}
2282
2283static struct ftrace_ops *
2284ftrace_find_tramp_ops_new(struct dyn_ftrace *rec)
2285{
2286 struct ftrace_ops *op;
2287 unsigned long ip = rec->ip;
2288
2289 do_for_each_ftrace_op(op, ftrace_ops_list) {
2290
2291 if (hash_contains_ip(ip, op->func_hash))
2292 return op;
2293 } while_for_each_ftrace_op(op);
2294
2295 return NULL;
2296}
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec)
2309{
2310 struct ftrace_ops *ops;
2311
2312
2313 if (rec->flags & FTRACE_FL_TRAMP) {
2314 ops = ftrace_find_tramp_ops_new(rec);
2315 if (FTRACE_WARN_ON(!ops || !ops->trampoline)) {
2316 pr_warn("Bad trampoline accounting at: %p (%pS) (%lx)\n",
2317 (void *)rec->ip, (void *)rec->ip, rec->flags);
2318
2319 return (unsigned long)FTRACE_ADDR;
2320 }
2321 return ops->trampoline;
2322 }
2323
2324 if (rec->flags & FTRACE_FL_REGS)
2325 return (unsigned long)FTRACE_REGS_ADDR;
2326 else
2327 return (unsigned long)FTRACE_ADDR;
2328}
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec)
2341{
2342 struct ftrace_ops *ops;
2343
2344
2345 if (rec->flags & FTRACE_FL_TRAMP_EN) {
2346 ops = ftrace_find_tramp_ops_curr(rec);
2347 if (FTRACE_WARN_ON(!ops)) {
2348 pr_warn("Bad trampoline accounting at: %p (%pS)\n",
2349 (void *)rec->ip, (void *)rec->ip);
2350
2351 return (unsigned long)FTRACE_ADDR;
2352 }
2353 return ops->trampoline;
2354 }
2355
2356 if (rec->flags & FTRACE_FL_REGS_EN)
2357 return (unsigned long)FTRACE_REGS_ADDR;
2358 else
2359 return (unsigned long)FTRACE_ADDR;
2360}
2361
2362static int
2363__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
2364{
2365 unsigned long ftrace_old_addr;
2366 unsigned long ftrace_addr;
2367 int ret;
2368
2369 ftrace_addr = ftrace_get_addr_new(rec);
2370
2371
2372 ftrace_old_addr = ftrace_get_addr_curr(rec);
2373
2374 ret = ftrace_update_record(rec, enable);
2375
2376 ftrace_bug_type = FTRACE_BUG_UNKNOWN;
2377
2378 switch (ret) {
2379 case FTRACE_UPDATE_IGNORE:
2380 return 0;
2381
2382 case FTRACE_UPDATE_MAKE_CALL:
2383 ftrace_bug_type = FTRACE_BUG_CALL;
2384 return ftrace_make_call(rec, ftrace_addr);
2385
2386 case FTRACE_UPDATE_MAKE_NOP:
2387 ftrace_bug_type = FTRACE_BUG_NOP;
2388 return ftrace_make_nop(NULL, rec, ftrace_old_addr);
2389
2390 case FTRACE_UPDATE_MODIFY_CALL:
2391 ftrace_bug_type = FTRACE_BUG_UPDATE;
2392 return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr);
2393 }
2394
2395 return -1;
2396}
2397
2398void __weak ftrace_replace_code(int mod_flags)
2399{
2400 struct dyn_ftrace *rec;
2401 struct ftrace_page *pg;
2402 int enable = mod_flags & FTRACE_MODIFY_ENABLE_FL;
2403 int schedulable = mod_flags & FTRACE_MODIFY_MAY_SLEEP_FL;
2404 int failed;
2405
2406 if (unlikely(ftrace_disabled))
2407 return;
2408
2409 do_for_each_ftrace_rec(pg, rec) {
2410
2411 if (rec->flags & FTRACE_FL_DISABLED)
2412 continue;
2413
2414 failed = __ftrace_replace_code(rec, enable);
2415 if (failed) {
2416 ftrace_bug(failed, rec);
2417
2418 return;
2419 }
2420 if (schedulable)
2421 cond_resched();
2422 } while_for_each_ftrace_rec();
2423}
2424
2425struct ftrace_rec_iter {
2426 struct ftrace_page *pg;
2427 int index;
2428};
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439struct ftrace_rec_iter *ftrace_rec_iter_start(void)
2440{
2441
2442
2443
2444
2445 static struct ftrace_rec_iter ftrace_rec_iter;
2446 struct ftrace_rec_iter *iter = &ftrace_rec_iter;
2447
2448 iter->pg = ftrace_pages_start;
2449 iter->index = 0;
2450
2451
2452 while (iter->pg && !iter->pg->index)
2453 iter->pg = iter->pg->next;
2454
2455 if (!iter->pg)
2456 return NULL;
2457
2458 return iter;
2459}
2460
2461
2462
2463
2464
2465
2466
2467struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter)
2468{
2469 iter->index++;
2470
2471 if (iter->index >= iter->pg->index) {
2472 iter->pg = iter->pg->next;
2473 iter->index = 0;
2474
2475
2476 while (iter->pg && !iter->pg->index)
2477 iter->pg = iter->pg->next;
2478 }
2479
2480 if (!iter->pg)
2481 return NULL;
2482
2483 return iter;
2484}
2485
2486
2487
2488
2489
2490
2491
2492struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter)
2493{
2494 return &iter->pg->records[iter->index];
2495}
2496
2497static int
2498ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec)
2499{
2500 int ret;
2501
2502 if (unlikely(ftrace_disabled))
2503 return 0;
2504
2505 ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR);
2506 if (ret) {
2507 ftrace_bug_type = FTRACE_BUG_INIT;
2508 ftrace_bug(ret, rec);
2509 return 0;
2510 }
2511 return 1;
2512}
2513
2514
2515
2516
2517
2518int __weak ftrace_arch_code_modify_prepare(void)
2519{
2520 return 0;
2521}
2522
2523
2524
2525
2526
2527int __weak ftrace_arch_code_modify_post_process(void)
2528{
2529 return 0;
2530}
2531
2532void ftrace_modify_all_code(int command)
2533{
2534 int update = command & FTRACE_UPDATE_TRACE_FUNC;
2535 int mod_flags = 0;
2536 int err = 0;
2537
2538 if (command & FTRACE_MAY_SLEEP)
2539 mod_flags = FTRACE_MODIFY_MAY_SLEEP_FL;
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551 if (update) {
2552 err = ftrace_update_ftrace_func(ftrace_ops_list_func);
2553 if (FTRACE_WARN_ON(err))
2554 return;
2555 }
2556
2557 if (command & FTRACE_UPDATE_CALLS)
2558 ftrace_replace_code(mod_flags | FTRACE_MODIFY_ENABLE_FL);
2559 else if (command & FTRACE_DISABLE_CALLS)
2560 ftrace_replace_code(mod_flags);
2561
2562 if (update && ftrace_trace_function != ftrace_ops_list_func) {
2563 function_trace_op = set_function_trace_op;
2564 smp_wmb();
2565
2566 if (!irqs_disabled())
2567 smp_call_function(ftrace_sync_ipi, NULL, 1);
2568 err = ftrace_update_ftrace_func(ftrace_trace_function);
2569 if (FTRACE_WARN_ON(err))
2570 return;
2571 }
2572
2573 if (command & FTRACE_START_FUNC_RET)
2574 err = ftrace_enable_ftrace_graph_caller();
2575 else if (command & FTRACE_STOP_FUNC_RET)
2576 err = ftrace_disable_ftrace_graph_caller();
2577 FTRACE_WARN_ON(err);
2578}
2579
2580static int __ftrace_modify_code(void *data)
2581{
2582 int *command = data;
2583
2584 ftrace_modify_all_code(*command);
2585
2586 return 0;
2587}
2588
2589
2590
2591
2592
2593
2594
2595
2596void ftrace_run_stop_machine(int command)
2597{
2598 stop_machine(__ftrace_modify_code, &command, NULL);
2599}
2600
2601
2602
2603
2604
2605
2606
2607
2608void __weak arch_ftrace_update_code(int command)
2609{
2610 ftrace_run_stop_machine(command);
2611}
2612
2613static void ftrace_run_update_code(int command)
2614{
2615 int ret;
2616
2617 ret = ftrace_arch_code_modify_prepare();
2618 FTRACE_WARN_ON(ret);
2619 if (ret)
2620 return;
2621
2622
2623
2624
2625
2626
2627
2628 arch_ftrace_update_code(command);
2629
2630 ret = ftrace_arch_code_modify_post_process();
2631 FTRACE_WARN_ON(ret);
2632}
2633
2634static void ftrace_run_modify_code(struct ftrace_ops *ops, int command,
2635 struct ftrace_ops_hash *old_hash)
2636{
2637 ops->flags |= FTRACE_OPS_FL_MODIFYING;
2638 ops->old_hash.filter_hash = old_hash->filter_hash;
2639 ops->old_hash.notrace_hash = old_hash->notrace_hash;
2640 ftrace_run_update_code(command);
2641 ops->old_hash.filter_hash = NULL;
2642 ops->old_hash.notrace_hash = NULL;
2643 ops->flags &= ~FTRACE_OPS_FL_MODIFYING;
2644}
2645
2646static ftrace_func_t saved_ftrace_func;
2647static int ftrace_start_up;
2648
2649void __weak arch_ftrace_trampoline_free(struct ftrace_ops *ops)
2650{
2651}
2652
2653static void ftrace_startup_enable(int command)
2654{
2655 if (saved_ftrace_func != ftrace_trace_function) {
2656 saved_ftrace_func = ftrace_trace_function;
2657 command |= FTRACE_UPDATE_TRACE_FUNC;
2658 }
2659
2660 if (!command || !ftrace_enabled)
2661 return;
2662
2663 ftrace_run_update_code(command);
2664}
2665
2666static void ftrace_startup_all(int command)
2667{
2668 update_all_ops = true;
2669 ftrace_startup_enable(command);
2670 update_all_ops = false;
2671}
2672
2673int ftrace_startup(struct ftrace_ops *ops, int command)
2674{
2675 int ret;
2676
2677 if (unlikely(ftrace_disabled))
2678 return -ENODEV;
2679
2680 ret = __register_ftrace_function(ops);
2681 if (ret)
2682 return ret;
2683
2684 ftrace_start_up++;
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694 ops->flags |= FTRACE_OPS_FL_ENABLED | FTRACE_OPS_FL_ADDING;
2695
2696 ret = ftrace_hash_ipmodify_enable(ops);
2697 if (ret < 0) {
2698
2699 __unregister_ftrace_function(ops);
2700 ftrace_start_up--;
2701 ops->flags &= ~FTRACE_OPS_FL_ENABLED;
2702 return ret;
2703 }
2704
2705 if (ftrace_hash_rec_enable(ops, 1))
2706 command |= FTRACE_UPDATE_CALLS;
2707
2708 ftrace_startup_enable(command);
2709
2710 ops->flags &= ~FTRACE_OPS_FL_ADDING;
2711
2712 return 0;
2713}
2714
2715int ftrace_shutdown(struct ftrace_ops *ops, int command)
2716{
2717 int ret;
2718
2719 if (unlikely(ftrace_disabled))
2720 return -ENODEV;
2721
2722 ret = __unregister_ftrace_function(ops);
2723 if (ret)
2724 return ret;
2725
2726 ftrace_start_up--;
2727
2728
2729
2730
2731
2732 WARN_ON_ONCE(ftrace_start_up < 0);
2733
2734
2735 ftrace_hash_ipmodify_disable(ops);
2736
2737 if (ftrace_hash_rec_disable(ops, 1))
2738 command |= FTRACE_UPDATE_CALLS;
2739
2740 ops->flags &= ~FTRACE_OPS_FL_ENABLED;
2741
2742 if (saved_ftrace_func != ftrace_trace_function) {
2743 saved_ftrace_func = ftrace_trace_function;
2744 command |= FTRACE_UPDATE_TRACE_FUNC;
2745 }
2746
2747 if (!command || !ftrace_enabled) {
2748
2749
2750
2751
2752
2753
2754 if (ops->flags & FTRACE_OPS_FL_DYNAMIC)
2755 goto free_ops;
2756
2757 return 0;
2758 }
2759
2760
2761
2762
2763
2764 ops->flags |= FTRACE_OPS_FL_REMOVING;
2765 removed_ops = ops;
2766
2767
2768 ops->old_hash.filter_hash = ops->func_hash->filter_hash;
2769 ops->old_hash.notrace_hash = ops->func_hash->notrace_hash;
2770
2771 ftrace_run_update_code(command);
2772
2773
2774
2775
2776
2777 if (rcu_dereference_protected(ftrace_ops_list,
2778 lockdep_is_held(&ftrace_lock)) == &ftrace_list_end) {
2779 struct ftrace_page *pg;
2780 struct dyn_ftrace *rec;
2781
2782 do_for_each_ftrace_rec(pg, rec) {
2783 if (FTRACE_WARN_ON_ONCE(rec->flags & ~FTRACE_FL_DISABLED))
2784 pr_warn(" %pS flags:%lx\n",
2785 (void *)rec->ip, rec->flags);
2786 } while_for_each_ftrace_rec();
2787 }
2788
2789 ops->old_hash.filter_hash = NULL;
2790 ops->old_hash.notrace_hash = NULL;
2791
2792 removed_ops = NULL;
2793 ops->flags &= ~FTRACE_OPS_FL_REMOVING;
2794
2795
2796
2797
2798
2799
2800
2801 if (ops->flags & FTRACE_OPS_FL_DYNAMIC) {
2802
2803
2804
2805
2806
2807
2808
2809
2810 schedule_on_each_cpu(ftrace_sync);
2811
2812
2813
2814
2815
2816
2817
2818
2819 if (IS_ENABLED(CONFIG_PREEMPT))
2820 synchronize_rcu_tasks();
2821
2822 free_ops:
2823 arch_ftrace_trampoline_free(ops);
2824 }
2825
2826 return 0;
2827}
2828
2829static void ftrace_startup_sysctl(void)
2830{
2831 int command;
2832
2833 if (unlikely(ftrace_disabled))
2834 return;
2835
2836
2837 saved_ftrace_func = NULL;
2838
2839 if (ftrace_start_up) {
2840 command = FTRACE_UPDATE_CALLS;
2841 if (ftrace_graph_active)
2842 command |= FTRACE_START_FUNC_RET;
2843 ftrace_startup_enable(command);
2844 }
2845}
2846
2847static void ftrace_shutdown_sysctl(void)
2848{
2849 int command;
2850
2851 if (unlikely(ftrace_disabled))
2852 return;
2853
2854
2855 if (ftrace_start_up) {
2856 command = FTRACE_DISABLE_CALLS;
2857 if (ftrace_graph_active)
2858 command |= FTRACE_STOP_FUNC_RET;
2859 ftrace_run_update_code(command);
2860 }
2861}
2862
2863static u64 ftrace_update_time;
2864unsigned long ftrace_update_tot_cnt;
2865
2866static inline int ops_traces_mod(struct ftrace_ops *ops)
2867{
2868
2869
2870
2871
2872 return ftrace_hash_empty(ops->func_hash->filter_hash) &&
2873 ftrace_hash_empty(ops->func_hash->notrace_hash);
2874}
2875
2876
2877
2878
2879
2880
2881
2882
2883static inline bool
2884ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec)
2885{
2886
2887 if (!(ops->flags & FTRACE_OPS_FL_ENABLED))
2888 return false;
2889
2890
2891 if (ops_traces_mod(ops))
2892 return true;
2893
2894
2895 if (!ftrace_hash_empty(ops->func_hash->filter_hash) &&
2896 !__ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip))
2897 return false;
2898
2899
2900 if (ftrace_lookup_ip(ops->func_hash->notrace_hash, rec->ip))
2901 return false;
2902
2903 return true;
2904}
2905
2906static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs)
2907{
2908 struct ftrace_page *pg;
2909 struct dyn_ftrace *p;
2910 u64 start, stop;
2911 unsigned long update_cnt = 0;
2912 unsigned long rec_flags = 0;
2913 int i;
2914
2915 start = ftrace_now(raw_smp_processor_id());
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928 if (mod)
2929 rec_flags |= FTRACE_FL_DISABLED;
2930
2931 for (pg = new_pgs; pg; pg = pg->next) {
2932
2933 for (i = 0; i < pg->index; i++) {
2934
2935
2936 if (unlikely(ftrace_disabled))
2937 return -1;
2938
2939 p = &pg->records[i];
2940 p->flags = rec_flags;
2941
2942#ifndef CC_USING_NOP_MCOUNT
2943
2944
2945
2946
2947 if (!ftrace_code_disable(mod, p))
2948 break;
2949#endif
2950
2951 update_cnt++;
2952 }
2953 }
2954
2955 stop = ftrace_now(raw_smp_processor_id());
2956 ftrace_update_time = stop - start;
2957 ftrace_update_tot_cnt += update_cnt;
2958
2959 return 0;
2960}
2961
2962static int ftrace_allocate_records(struct ftrace_page *pg, int count)
2963{
2964 int order;
2965 int cnt;
2966
2967 if (WARN_ON(!count))
2968 return -EINVAL;
2969
2970 order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE));
2971
2972
2973
2974
2975
2976 while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE)
2977 order--;
2978
2979 again:
2980 pg->records = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, order);
2981
2982 if (!pg->records) {
2983
2984 if (!order)
2985 return -ENOMEM;
2986 order >>= 1;
2987 goto again;
2988 }
2989
2990 cnt = (PAGE_SIZE << order) / ENTRY_SIZE;
2991 pg->size = cnt;
2992
2993 if (cnt > count)
2994 cnt = count;
2995
2996 return cnt;
2997}
2998
2999static struct ftrace_page *
3000ftrace_allocate_pages(unsigned long num_to_init)
3001{
3002 struct ftrace_page *start_pg;
3003 struct ftrace_page *pg;
3004 int order;
3005 int cnt;
3006
3007 if (!num_to_init)
3008 return NULL;
3009
3010 start_pg = pg = kzalloc(sizeof(*pg), GFP_KERNEL);
3011 if (!pg)
3012 return NULL;
3013
3014
3015
3016
3017
3018
3019 for (;;) {
3020 cnt = ftrace_allocate_records(pg, num_to_init);
3021 if (cnt < 0)
3022 goto free_pages;
3023
3024 num_to_init -= cnt;
3025 if (!num_to_init)
3026 break;
3027
3028 pg->next = kzalloc(sizeof(*pg), GFP_KERNEL);
3029 if (!pg->next)
3030 goto free_pages;
3031
3032 pg = pg->next;
3033 }
3034
3035 return start_pg;
3036
3037 free_pages:
3038 pg = start_pg;
3039 while (pg) {
3040 order = get_count_order(pg->size / ENTRIES_PER_PAGE);
3041 free_pages((unsigned long)pg->records, order);
3042 start_pg = pg->next;
3043 kfree(pg);
3044 pg = start_pg;
3045 }
3046 pr_info("ftrace: FAILED to allocate memory for functions\n");
3047 return NULL;
3048}
3049
3050#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4)
3051
3052struct ftrace_iterator {
3053 loff_t pos;
3054 loff_t func_pos;
3055 loff_t mod_pos;
3056 struct ftrace_page *pg;
3057 struct dyn_ftrace *func;
3058 struct ftrace_func_probe *probe;
3059 struct ftrace_func_entry *probe_entry;
3060 struct trace_parser parser;
3061 struct ftrace_hash *hash;
3062 struct ftrace_ops *ops;
3063 struct trace_array *tr;
3064 struct list_head *mod_list;
3065 int pidx;
3066 int idx;
3067 unsigned flags;
3068};
3069
3070static void *
3071t_probe_next(struct seq_file *m, loff_t *pos)
3072{
3073 struct ftrace_iterator *iter = m->private;
3074 struct trace_array *tr = iter->ops->private;
3075 struct list_head *func_probes;
3076 struct ftrace_hash *hash;
3077 struct list_head *next;
3078 struct hlist_node *hnd = NULL;
3079 struct hlist_head *hhd;
3080 int size;
3081
3082 (*pos)++;
3083 iter->pos = *pos;
3084
3085 if (!tr)
3086 return NULL;
3087
3088 func_probes = &tr->func_probes;
3089 if (list_empty(func_probes))
3090 return NULL;
3091
3092 if (!iter->probe) {
3093 next = func_probes->next;
3094 iter->probe = list_entry(next, struct ftrace_func_probe, list);
3095 }
3096
3097 if (iter->probe_entry)
3098 hnd = &iter->probe_entry->hlist;
3099
3100 hash = iter->probe->ops.func_hash->filter_hash;
3101 size = 1 << hash->size_bits;
3102
3103 retry:
3104 if (iter->pidx >= size) {
3105 if (iter->probe->list.next == func_probes)
3106 return NULL;
3107 next = iter->probe->list.next;
3108 iter->probe = list_entry(next, struct ftrace_func_probe, list);
3109 hash = iter->probe->ops.func_hash->filter_hash;
3110 size = 1 << hash->size_bits;
3111 iter->pidx = 0;
3112 }
3113
3114 hhd = &hash->buckets[iter->pidx];
3115
3116 if (hlist_empty(hhd)) {
3117 iter->pidx++;
3118 hnd = NULL;
3119 goto retry;
3120 }
3121
3122 if (!hnd)
3123 hnd = hhd->first;
3124 else {
3125 hnd = hnd->next;
3126 if (!hnd) {
3127 iter->pidx++;
3128 goto retry;
3129 }
3130 }
3131
3132 if (WARN_ON_ONCE(!hnd))
3133 return NULL;
3134
3135 iter->probe_entry = hlist_entry(hnd, struct ftrace_func_entry, hlist);
3136
3137 return iter;
3138}
3139
3140static void *t_probe_start(struct seq_file *m, loff_t *pos)
3141{
3142 struct ftrace_iterator *iter = m->private;
3143 void *p = NULL;
3144 loff_t l;
3145
3146 if (!(iter->flags & FTRACE_ITER_DO_PROBES))
3147 return NULL;
3148
3149 if (iter->mod_pos > *pos)
3150 return NULL;
3151
3152 iter->probe = NULL;
3153 iter->probe_entry = NULL;
3154 iter->pidx = 0;
3155 for (l = 0; l <= (*pos - iter->mod_pos); ) {
3156 p = t_probe_next(m, &l);
3157 if (!p)
3158 break;
3159 }
3160 if (!p)
3161 return NULL;
3162
3163
3164 iter->flags |= FTRACE_ITER_PROBE;
3165
3166 return iter;
3167}
3168
3169static int
3170t_probe_show(struct seq_file *m, struct ftrace_iterator *iter)
3171{
3172 struct ftrace_func_entry *probe_entry;
3173 struct ftrace_probe_ops *probe_ops;
3174 struct ftrace_func_probe *probe;
3175
3176 probe = iter->probe;
3177 probe_entry = iter->probe_entry;
3178
3179 if (WARN_ON_ONCE(!probe || !probe_entry))
3180 return -EIO;
3181
3182 probe_ops = probe->probe_ops;
3183
3184 if (probe_ops->print)
3185 return probe_ops->print(m, probe_entry->ip, probe_ops, probe->data);
3186
3187 seq_printf(m, "%ps:%ps\n", (void *)probe_entry->ip,
3188 (void *)probe_ops->func);
3189
3190 return 0;
3191}
3192
3193static void *
3194t_mod_next(struct seq_file *m, loff_t *pos)
3195{
3196 struct ftrace_iterator *iter = m->private;
3197 struct trace_array *tr = iter->tr;
3198
3199 (*pos)++;
3200 iter->pos = *pos;
3201
3202 iter->mod_list = iter->mod_list->next;
3203
3204 if (iter->mod_list == &tr->mod_trace ||
3205 iter->mod_list == &tr->mod_notrace) {
3206 iter->flags &= ~FTRACE_ITER_MOD;
3207 return NULL;
3208 }
3209
3210 iter->mod_pos = *pos;
3211
3212 return iter;
3213}
3214
3215static void *t_mod_start(struct seq_file *m, loff_t *pos)
3216{
3217 struct ftrace_iterator *iter = m->private;
3218 void *p = NULL;
3219 loff_t l;
3220
3221 if (iter->func_pos > *pos)
3222 return NULL;
3223
3224 iter->mod_pos = iter->func_pos;
3225
3226
3227 if (!iter->tr)
3228 return NULL;
3229
3230 for (l = 0; l <= (*pos - iter->func_pos); ) {
3231 p = t_mod_next(m, &l);
3232 if (!p)
3233 break;
3234 }
3235 if (!p) {
3236 iter->flags &= ~FTRACE_ITER_MOD;
3237 return t_probe_start(m, pos);
3238 }
3239
3240
3241 iter->flags |= FTRACE_ITER_MOD;
3242
3243 return iter;
3244}
3245
3246static int
3247t_mod_show(struct seq_file *m, struct ftrace_iterator *iter)
3248{
3249 struct ftrace_mod_load *ftrace_mod;
3250 struct trace_array *tr = iter->tr;
3251
3252 if (WARN_ON_ONCE(!iter->mod_list) ||
3253 iter->mod_list == &tr->mod_trace ||
3254 iter->mod_list == &tr->mod_notrace)
3255 return -EIO;
3256
3257 ftrace_mod = list_entry(iter->mod_list, struct ftrace_mod_load, list);
3258
3259 if (ftrace_mod->func)
3260 seq_printf(m, "%s", ftrace_mod->func);
3261 else
3262 seq_putc(m, '*');
3263
3264 seq_printf(m, ":mod:%s\n", ftrace_mod->module);
3265
3266 return 0;
3267}
3268
3269static void *
3270t_func_next(struct seq_file *m, loff_t *pos)
3271{
3272 struct ftrace_iterator *iter = m->private;
3273 struct dyn_ftrace *rec = NULL;
3274
3275 (*pos)++;
3276
3277 retry:
3278 if (iter->idx >= iter->pg->index) {
3279 if (iter->pg->next) {
3280 iter->pg = iter->pg->next;
3281 iter->idx = 0;
3282 goto retry;
3283 }
3284 } else {
3285 rec = &iter->pg->records[iter->idx++];
3286 if (((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) &&
3287 !ftrace_lookup_ip(iter->hash, rec->ip)) ||
3288
3289 ((iter->flags & FTRACE_ITER_ENABLED) &&
3290 !(rec->flags & FTRACE_FL_ENABLED))) {
3291
3292 rec = NULL;
3293 goto retry;
3294 }
3295 }
3296
3297 if (!rec)
3298 return NULL;
3299
3300 iter->pos = iter->func_pos = *pos;
3301 iter->func = rec;
3302
3303 return iter;
3304}
3305
3306static void *
3307t_next(struct seq_file *m, void *v, loff_t *pos)
3308{
3309 struct ftrace_iterator *iter = m->private;
3310 loff_t l = *pos;
3311 void *ret;
3312
3313 if (unlikely(ftrace_disabled))
3314 return NULL;
3315
3316 if (iter->flags & FTRACE_ITER_PROBE)
3317 return t_probe_next(m, pos);
3318
3319 if (iter->flags & FTRACE_ITER_MOD)
3320 return t_mod_next(m, pos);
3321
3322 if (iter->flags & FTRACE_ITER_PRINTALL) {
3323
3324 (*pos)++;
3325 return t_mod_start(m, &l);
3326 }
3327
3328 ret = t_func_next(m, pos);
3329
3330 if (!ret)
3331 return t_mod_start(m, &l);
3332
3333 return ret;
3334}
3335
3336static void reset_iter_read(struct ftrace_iterator *iter)
3337{
3338 iter->pos = 0;
3339 iter->func_pos = 0;
3340 iter->flags &= ~(FTRACE_ITER_PRINTALL | FTRACE_ITER_PROBE | FTRACE_ITER_MOD);
3341}
3342
3343static void *t_start(struct seq_file *m, loff_t *pos)
3344{
3345 struct ftrace_iterator *iter = m->private;
3346 void *p = NULL;
3347 loff_t l;
3348
3349 mutex_lock(&ftrace_lock);
3350
3351 if (unlikely(ftrace_disabled))
3352 return NULL;
3353
3354
3355
3356
3357 if (*pos < iter->pos)
3358 reset_iter_read(iter);
3359
3360
3361
3362
3363
3364
3365 if ((iter->flags & (FTRACE_ITER_FILTER | FTRACE_ITER_NOTRACE)) &&
3366 ftrace_hash_empty(iter->hash)) {
3367 iter->func_pos = 1;
3368 if (*pos > 0)
3369 return t_mod_start(m, pos);
3370 iter->flags |= FTRACE_ITER_PRINTALL;
3371
3372 iter->flags &= ~FTRACE_ITER_PROBE;
3373 return iter;
3374 }
3375
3376 if (iter->flags & FTRACE_ITER_MOD)
3377 return t_mod_start(m, pos);
3378
3379
3380
3381
3382
3383
3384 iter->pg = ftrace_pages_start;
3385 iter->idx = 0;
3386 for (l = 0; l <= *pos; ) {
3387 p = t_func_next(m, &l);
3388 if (!p)
3389 break;
3390 }
3391
3392 if (!p)
3393 return t_mod_start(m, pos);
3394
3395 return iter;
3396}
3397
3398static void t_stop(struct seq_file *m, void *p)
3399{
3400 mutex_unlock(&ftrace_lock);
3401}
3402
3403void * __weak
3404arch_ftrace_trampoline_func(struct ftrace_ops *ops, struct dyn_ftrace *rec)
3405{
3406 return NULL;
3407}
3408
3409static void add_trampoline_func(struct seq_file *m, struct ftrace_ops *ops,
3410 struct dyn_ftrace *rec)
3411{
3412 void *ptr;
3413
3414 ptr = arch_ftrace_trampoline_func(ops, rec);
3415 if (ptr)
3416 seq_printf(m, " ->%pS", ptr);
3417}
3418
3419static int t_show(struct seq_file *m, void *v)
3420{
3421 struct ftrace_iterator *iter = m->private;
3422 struct dyn_ftrace *rec;
3423
3424 if (iter->flags & FTRACE_ITER_PROBE)
3425 return t_probe_show(m, iter);
3426
3427 if (iter->flags & FTRACE_ITER_MOD)
3428 return t_mod_show(m, iter);
3429
3430 if (iter->flags & FTRACE_ITER_PRINTALL) {
3431 if (iter->flags & FTRACE_ITER_NOTRACE)
3432 seq_puts(m, "#### no functions disabled ####\n");
3433 else
3434 seq_puts(m, "#### all functions enabled ####\n");
3435 return 0;
3436 }
3437
3438 rec = iter->func;
3439
3440 if (!rec)
3441 return 0;
3442
3443 seq_printf(m, "%ps", (void *)rec->ip);
3444 if (iter->flags & FTRACE_ITER_ENABLED) {
3445 struct ftrace_ops *ops;
3446
3447 seq_printf(m, " (%ld)%s%s",
3448 ftrace_rec_count(rec),
3449 rec->flags & FTRACE_FL_REGS ? " R" : " ",
3450 rec->flags & FTRACE_FL_IPMODIFY ? " I" : " ");
3451 if (rec->flags & FTRACE_FL_TRAMP_EN) {
3452 ops = ftrace_find_tramp_ops_any(rec);
3453 if (ops) {
3454 do {
3455 seq_printf(m, "\ttramp: %pS (%pS)",
3456 (void *)ops->trampoline,
3457 (void *)ops->func);
3458 add_trampoline_func(m, ops, rec);
3459 ops = ftrace_find_tramp_ops_next(rec, ops);
3460 } while (ops);
3461 } else
3462 seq_puts(m, "\ttramp: ERROR!");
3463 } else {
3464 add_trampoline_func(m, NULL, rec);
3465 }
3466 }
3467
3468 seq_putc(m, '\n');
3469
3470 return 0;
3471}
3472
3473static const struct seq_operations show_ftrace_seq_ops = {
3474 .start = t_start,
3475 .next = t_next,
3476 .stop = t_stop,
3477 .show = t_show,
3478};
3479
3480static int
3481ftrace_avail_open(struct inode *inode, struct file *file)
3482{
3483 struct ftrace_iterator *iter;
3484
3485 if (unlikely(ftrace_disabled))
3486 return -ENODEV;
3487
3488 iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter));
3489 if (!iter)
3490 return -ENOMEM;
3491
3492 iter->pg = ftrace_pages_start;
3493 iter->ops = &global_ops;
3494
3495 return 0;
3496}
3497
3498static int
3499ftrace_enabled_open(struct inode *inode, struct file *file)
3500{
3501 struct ftrace_iterator *iter;
3502
3503 iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter));
3504 if (!iter)
3505 return -ENOMEM;
3506
3507 iter->pg = ftrace_pages_start;
3508 iter->flags = FTRACE_ITER_ENABLED;
3509 iter->ops = &global_ops;
3510
3511 return 0;
3512}
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530int
3531ftrace_regex_open(struct ftrace_ops *ops, int flag,
3532 struct inode *inode, struct file *file)
3533{
3534 struct ftrace_iterator *iter;
3535 struct ftrace_hash *hash;
3536 struct list_head *mod_head;
3537 struct trace_array *tr = ops->private;
3538 int ret = 0;
3539
3540 ftrace_ops_init(ops);
3541
3542 if (unlikely(ftrace_disabled))
3543 return -ENODEV;
3544
3545 iter = kzalloc(sizeof(*iter), GFP_KERNEL);
3546 if (!iter)
3547 return -ENOMEM;
3548
3549 if (trace_parser_get_init(&iter->parser, FTRACE_BUFF_MAX)) {
3550 kfree(iter);
3551 return -ENOMEM;
3552 }
3553
3554 iter->ops = ops;
3555 iter->flags = flag;
3556 iter->tr = tr;
3557
3558 mutex_lock(&ops->func_hash->regex_lock);
3559
3560 if (flag & FTRACE_ITER_NOTRACE) {
3561 hash = ops->func_hash->notrace_hash;
3562 mod_head = tr ? &tr->mod_notrace : NULL;
3563 } else {
3564 hash = ops->func_hash->filter_hash;
3565 mod_head = tr ? &tr->mod_trace : NULL;
3566 }
3567
3568 iter->mod_list = mod_head;
3569
3570 if (file->f_mode & FMODE_WRITE) {
3571 const int size_bits = FTRACE_HASH_DEFAULT_BITS;
3572
3573 if (file->f_flags & O_TRUNC) {
3574 iter->hash = alloc_ftrace_hash(size_bits);
3575 clear_ftrace_mod_list(mod_head);
3576 } else {
3577 iter->hash = alloc_and_copy_ftrace_hash(size_bits, hash);
3578 }
3579
3580 if (!iter->hash) {
3581 trace_parser_put(&iter->parser);
3582 kfree(iter);
3583 ret = -ENOMEM;
3584 goto out_unlock;
3585 }
3586 } else
3587 iter->hash = hash;
3588
3589 if (file->f_mode & FMODE_READ) {
3590 iter->pg = ftrace_pages_start;
3591
3592 ret = seq_open(file, &show_ftrace_seq_ops);
3593 if (!ret) {
3594 struct seq_file *m = file->private_data;
3595 m->private = iter;
3596 } else {
3597
3598 free_ftrace_hash(iter->hash);
3599 trace_parser_put(&iter->parser);
3600 kfree(iter);
3601 }
3602 } else
3603 file->private_data = iter;
3604
3605 out_unlock:
3606 mutex_unlock(&ops->func_hash->regex_lock);
3607
3608 return ret;
3609}
3610
3611static int
3612ftrace_filter_open(struct inode *inode, struct file *file)
3613{
3614 struct ftrace_ops *ops = inode->i_private;
3615
3616 return ftrace_regex_open(ops,
3617 FTRACE_ITER_FILTER | FTRACE_ITER_DO_PROBES,
3618 inode, file);
3619}
3620
3621static int
3622ftrace_notrace_open(struct inode *inode, struct file *file)
3623{
3624 struct ftrace_ops *ops = inode->i_private;
3625
3626 return ftrace_regex_open(ops, FTRACE_ITER_NOTRACE,
3627 inode, file);
3628}
3629
3630
3631struct ftrace_glob {
3632 char *search;
3633 unsigned len;
3634 int type;
3635};
3636
3637
3638
3639
3640
3641
3642char * __weak arch_ftrace_match_adjust(char *str, const char *search)
3643{
3644 return str;
3645}
3646
3647static int ftrace_match(char *str, struct ftrace_glob *g)
3648{
3649 int matched = 0;
3650 int slen;
3651
3652 str = arch_ftrace_match_adjust(str, g->search);
3653
3654 switch (g->type) {
3655 case MATCH_FULL:
3656 if (strcmp(str, g->search) == 0)
3657 matched = 1;
3658 break;
3659 case MATCH_FRONT_ONLY:
3660 if (strncmp(str, g->search, g->len) == 0)
3661 matched = 1;
3662 break;
3663 case MATCH_MIDDLE_ONLY:
3664 if (strstr(str, g->search))
3665 matched = 1;
3666 break;
3667 case MATCH_END_ONLY:
3668 slen = strlen(str);
3669 if (slen >= g->len &&
3670 memcmp(str + slen - g->len, g->search, g->len) == 0)
3671 matched = 1;
3672 break;
3673 case MATCH_GLOB:
3674 if (glob_match(g->search, str))
3675 matched = 1;
3676 break;
3677 }
3678
3679 return matched;
3680}
3681
3682static int
3683enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int clear_filter)
3684{
3685 struct ftrace_func_entry *entry;
3686 int ret = 0;
3687
3688 entry = ftrace_lookup_ip(hash, rec->ip);
3689 if (clear_filter) {
3690
3691 if (!entry)
3692 return 0;
3693
3694 free_hash_entry(hash, entry);
3695 } else {
3696
3697 if (entry)
3698 return 0;
3699
3700 ret = add_hash_entry(hash, rec->ip);
3701 }
3702 return ret;
3703}
3704
3705static int
3706add_rec_by_index(struct ftrace_hash *hash, struct ftrace_glob *func_g,
3707 int clear_filter)
3708{
3709 long index = simple_strtoul(func_g->search, NULL, 0);
3710 struct ftrace_page *pg;
3711 struct dyn_ftrace *rec;
3712
3713
3714 if (--index < 0)
3715 return 0;
3716
3717 do_for_each_ftrace_rec(pg, rec) {
3718 if (pg->index <= index) {
3719 index -= pg->index;
3720
3721 break;
3722 }
3723 rec = &pg->records[index];
3724 enter_record(hash, rec, clear_filter);
3725 return 1;
3726 } while_for_each_ftrace_rec();
3727 return 0;
3728}
3729
3730static int
3731ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g,
3732 struct ftrace_glob *mod_g, int exclude_mod)
3733{
3734 char str[KSYM_SYMBOL_LEN];
3735 char *modname;
3736
3737 kallsyms_lookup(rec->ip, NULL, NULL, &modname, str);
3738
3739 if (mod_g) {
3740 int mod_matches = (modname) ? ftrace_match(modname, mod_g) : 0;
3741
3742
3743 if (!mod_g->len) {
3744
3745 if (!exclude_mod != !modname)
3746 goto func_match;
3747 return 0;
3748 }
3749
3750
3751
3752
3753
3754
3755
3756
3757 if (!mod_matches == !exclude_mod)
3758 return 0;
3759func_match:
3760
3761 if (!func_g->len)
3762 return 1;
3763 }
3764
3765 return ftrace_match(str, func_g);
3766}
3767
3768static int
3769match_records(struct ftrace_hash *hash, char *func, int len, char *mod)
3770{
3771 struct ftrace_page *pg;
3772 struct dyn_ftrace *rec;
3773 struct ftrace_glob func_g = { .type = MATCH_FULL };
3774 struct ftrace_glob mod_g = { .type = MATCH_FULL };
3775 struct ftrace_glob *mod_match = (mod) ? &mod_g : NULL;
3776 int exclude_mod = 0;
3777 int found = 0;
3778 int ret;
3779 int clear_filter = 0;
3780
3781 if (func) {
3782 func_g.type = filter_parse_regex(func, len, &func_g.search,
3783 &clear_filter);
3784 func_g.len = strlen(func_g.search);
3785 }
3786
3787 if (mod) {
3788 mod_g.type = filter_parse_regex(mod, strlen(mod),
3789 &mod_g.search, &exclude_mod);
3790 mod_g.len = strlen(mod_g.search);
3791 }
3792
3793 mutex_lock(&ftrace_lock);
3794
3795 if (unlikely(ftrace_disabled))
3796 goto out_unlock;
3797
3798 if (func_g.type == MATCH_INDEX) {
3799 found = add_rec_by_index(hash, &func_g, clear_filter);
3800 goto out_unlock;
3801 }
3802
3803 do_for_each_ftrace_rec(pg, rec) {
3804
3805 if (rec->flags & FTRACE_FL_DISABLED)
3806 continue;
3807
3808 if (ftrace_match_record(rec, &func_g, mod_match, exclude_mod)) {
3809 ret = enter_record(hash, rec, clear_filter);
3810 if (ret < 0) {
3811 found = ret;
3812 goto out_unlock;
3813 }
3814 found = 1;
3815 }
3816 } while_for_each_ftrace_rec();
3817 out_unlock:
3818 mutex_unlock(&ftrace_lock);
3819
3820 return found;
3821}
3822
3823static int
3824ftrace_match_records(struct ftrace_hash *hash, char *buff, int len)
3825{
3826 return match_records(hash, buff, len, NULL);
3827}
3828
3829static void ftrace_ops_update_code(struct ftrace_ops *ops,
3830 struct ftrace_ops_hash *old_hash)
3831{
3832 struct ftrace_ops *op;
3833
3834 if (!ftrace_enabled)
3835 return;
3836
3837 if (ops->flags & FTRACE_OPS_FL_ENABLED) {
3838 ftrace_run_modify_code(ops, FTRACE_UPDATE_CALLS, old_hash);
3839 return;
3840 }
3841
3842
3843
3844
3845
3846
3847 if (ops->func_hash != &global_ops.local_hash)
3848 return;
3849
3850 do_for_each_ftrace_op(op, ftrace_ops_list) {
3851 if (op->func_hash == &global_ops.local_hash &&
3852 op->flags & FTRACE_OPS_FL_ENABLED) {
3853 ftrace_run_modify_code(op, FTRACE_UPDATE_CALLS, old_hash);
3854
3855 return;
3856 }
3857 } while_for_each_ftrace_op(op);
3858}
3859
3860static int ftrace_hash_move_and_update_ops(struct ftrace_ops *ops,
3861 struct ftrace_hash **orig_hash,
3862 struct ftrace_hash *hash,
3863 int enable)
3864{
3865 struct ftrace_ops_hash old_hash_ops;
3866 struct ftrace_hash *old_hash;
3867 int ret;
3868
3869 old_hash = *orig_hash;
3870 old_hash_ops.filter_hash = ops->func_hash->filter_hash;
3871 old_hash_ops.notrace_hash = ops->func_hash->notrace_hash;
3872 ret = ftrace_hash_move(ops, enable, orig_hash, hash);
3873 if (!ret) {
3874 ftrace_ops_update_code(ops, &old_hash_ops);
3875 free_ftrace_hash_rcu(old_hash);
3876 }
3877 return ret;
3878}
3879
3880static bool module_exists(const char *module)
3881{
3882
3883 const char this_mod[] = "__this_module";
3884 char modname[MAX_PARAM_PREFIX_LEN + sizeof(this_mod) + 2];
3885 unsigned long val;
3886 int n;
3887
3888 n = snprintf(modname, sizeof(modname), "%s:%s", module, this_mod);
3889
3890 if (n > sizeof(modname) - 1)
3891 return false;
3892
3893 val = module_kallsyms_lookup_name(modname);
3894 return val != 0;
3895}
3896
3897static int cache_mod(struct trace_array *tr,
3898 const char *func, char *module, int enable)
3899{
3900 struct ftrace_mod_load *ftrace_mod, *n;
3901 struct list_head *head = enable ? &tr->mod_trace : &tr->mod_notrace;
3902 int ret;
3903
3904 mutex_lock(&ftrace_lock);
3905
3906
3907 if (func[0] == '!') {
3908 func++;
3909 ret = -EINVAL;
3910
3911
3912 list_for_each_entry_safe(ftrace_mod, n, head, list) {
3913 if (strcmp(ftrace_mod->module, module) != 0)
3914 continue;
3915
3916
3917 if (strcmp(func, "*") == 0 ||
3918 (ftrace_mod->func &&
3919 strcmp(ftrace_mod->func, func) == 0)) {
3920 ret = 0;
3921 free_ftrace_mod(ftrace_mod);
3922 continue;
3923 }
3924 }
3925 goto out;
3926 }
3927
3928 ret = -EINVAL;
3929
3930 if (module_exists(module))
3931 goto out;
3932
3933
3934 ret = ftrace_add_mod(tr, func, module, enable);
3935 out:
3936 mutex_unlock(&ftrace_lock);
3937
3938 return ret;
3939}
3940
3941static int
3942ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
3943 int reset, int enable);
3944
3945#ifdef CONFIG_MODULES
3946static void process_mod_list(struct list_head *head, struct ftrace_ops *ops,
3947 char *mod, bool enable)
3948{
3949 struct ftrace_mod_load *ftrace_mod, *n;
3950 struct ftrace_hash **orig_hash, *new_hash;
3951 LIST_HEAD(process_mods);
3952 char *func;
3953 int ret;
3954
3955 mutex_lock(&ops->func_hash->regex_lock);
3956
3957 if (enable)
3958 orig_hash = &ops->func_hash->filter_hash;
3959 else
3960 orig_hash = &ops->func_hash->notrace_hash;
3961
3962 new_hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS,
3963 *orig_hash);
3964 if (!new_hash)
3965 goto out;
3966
3967 mutex_lock(&ftrace_lock);
3968
3969 list_for_each_entry_safe(ftrace_mod, n, head, list) {
3970
3971 if (strcmp(ftrace_mod->module, mod) != 0)
3972 continue;
3973
3974 if (ftrace_mod->func)
3975 func = kstrdup(ftrace_mod->func, GFP_KERNEL);
3976 else
3977 func = kstrdup("*", GFP_KERNEL);
3978
3979 if (!func)
3980 continue;
3981
3982 list_del(&ftrace_mod->list);
3983 list_add(&ftrace_mod->list, &process_mods);
3984
3985
3986 kfree(ftrace_mod->func);
3987 ftrace_mod->func = func;
3988 }
3989
3990 mutex_unlock(&ftrace_lock);
3991
3992 list_for_each_entry_safe(ftrace_mod, n, &process_mods, list) {
3993
3994 func = ftrace_mod->func;
3995
3996
3997 match_records(new_hash, func, strlen(func), mod);
3998 free_ftrace_mod(ftrace_mod);
3999 }
4000
4001 if (enable && list_empty(head))
4002 new_hash->flags &= ~FTRACE_HASH_FL_MOD;
4003
4004 mutex_lock(&ftrace_lock);
4005
4006 ret = ftrace_hash_move_and_update_ops(ops, orig_hash,
4007 new_hash, enable);
4008 mutex_unlock(&ftrace_lock);
4009
4010 out:
4011 mutex_unlock(&ops->func_hash->regex_lock);
4012
4013 free_ftrace_hash(new_hash);
4014}
4015
4016static void process_cached_mods(const char *mod_name)
4017{
4018 struct trace_array *tr;
4019 char *mod;
4020
4021 mod = kstrdup(mod_name, GFP_KERNEL);
4022 if (!mod)
4023 return;
4024
4025 mutex_lock(&trace_types_lock);
4026 list_for_each_entry(tr, &ftrace_trace_arrays, list) {
4027 if (!list_empty(&tr->mod_trace))
4028 process_mod_list(&tr->mod_trace, tr->ops, mod, true);
4029 if (!list_empty(&tr->mod_notrace))
4030 process_mod_list(&tr->mod_notrace, tr->ops, mod, false);
4031 }
4032 mutex_unlock(&trace_types_lock);
4033
4034 kfree(mod);
4035}
4036#endif
4037
4038
4039
4040
4041
4042
4043static int
4044ftrace_mod_callback(struct trace_array *tr, struct ftrace_hash *hash,
4045 char *func_orig, char *cmd, char *module, int enable)
4046{
4047 char *func;
4048 int ret;
4049
4050
4051 func = kstrdup(func_orig, GFP_KERNEL);
4052 if (!func)
4053 return -ENOMEM;
4054
4055
4056
4057
4058
4059
4060
4061
4062 ret = match_records(hash, func, strlen(func), module);
4063 kfree(func);
4064
4065 if (!ret)
4066 return cache_mod(tr, func_orig, module, enable);
4067 if (ret < 0)
4068 return ret;
4069 return 0;
4070}
4071
4072static struct ftrace_func_command ftrace_mod_cmd = {
4073 .name = "mod",
4074 .func = ftrace_mod_callback,
4075};
4076
4077static int __init ftrace_mod_cmd_init(void)
4078{
4079 return register_ftrace_command(&ftrace_mod_cmd);
4080}
4081core_initcall(ftrace_mod_cmd_init);
4082
4083static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip,
4084 struct ftrace_ops *op, struct pt_regs *pt_regs)
4085{
4086 struct ftrace_probe_ops *probe_ops;
4087 struct ftrace_func_probe *probe;
4088
4089 probe = container_of(op, struct ftrace_func_probe, ops);
4090 probe_ops = probe->probe_ops;
4091
4092
4093
4094
4095
4096
4097 preempt_disable_notrace();
4098 probe_ops->func(ip, parent_ip, probe->tr, probe_ops, probe->data);
4099 preempt_enable_notrace();
4100}
4101
4102struct ftrace_func_map {
4103 struct ftrace_func_entry entry;
4104 void *data;
4105};
4106
4107struct ftrace_func_mapper {
4108 struct ftrace_hash hash;
4109};
4110
4111
4112
4113
4114
4115
4116struct ftrace_func_mapper *allocate_ftrace_func_mapper(void)
4117{
4118 struct ftrace_hash *hash;
4119
4120
4121
4122
4123
4124
4125 hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS);
4126 return (struct ftrace_func_mapper *)hash;
4127}
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
4141 unsigned long ip)
4142{
4143 struct ftrace_func_entry *entry;
4144 struct ftrace_func_map *map;
4145
4146 entry = ftrace_lookup_ip(&mapper->hash, ip);
4147 if (!entry)
4148 return NULL;
4149
4150 map = (struct ftrace_func_map *)entry;
4151 return &map->data;
4152}
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
4163 unsigned long ip, void *data)
4164{
4165 struct ftrace_func_entry *entry;
4166 struct ftrace_func_map *map;
4167
4168 entry = ftrace_lookup_ip(&mapper->hash, ip);
4169 if (entry)
4170 return -EBUSY;
4171
4172 map = kmalloc(sizeof(*map), GFP_KERNEL);
4173 if (!map)
4174 return -ENOMEM;
4175
4176 map->entry.ip = ip;
4177 map->data = data;
4178
4179 __add_hash_entry(&mapper->hash, &map->entry);
4180
4181 return 0;
4182}
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
4195 unsigned long ip)
4196{
4197 struct ftrace_func_entry *entry;
4198 struct ftrace_func_map *map;
4199 void *data;
4200
4201 entry = ftrace_lookup_ip(&mapper->hash, ip);
4202 if (!entry)
4203 return NULL;
4204
4205 map = (struct ftrace_func_map *)entry;
4206 data = map->data;
4207
4208 remove_hash_entry(&mapper->hash, entry);
4209 kfree(entry);
4210
4211 return data;
4212}
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
4223 ftrace_mapper_func free_func)
4224{
4225 struct ftrace_func_entry *entry;
4226 struct ftrace_func_map *map;
4227 struct hlist_head *hhd;
4228 int size = 1 << mapper->hash.size_bits;
4229 int i;
4230
4231 if (free_func && mapper->hash.count) {
4232 for (i = 0; i < size; i++) {
4233 hhd = &mapper->hash.buckets[i];
4234 hlist_for_each_entry(entry, hhd, hlist) {
4235 map = (struct ftrace_func_map *)entry;
4236 free_func(map);
4237 }
4238 }
4239 }
4240 free_ftrace_hash(&mapper->hash);
4241}
4242
4243static void release_probe(struct ftrace_func_probe *probe)
4244{
4245 struct ftrace_probe_ops *probe_ops;
4246
4247 mutex_lock(&ftrace_lock);
4248
4249 WARN_ON(probe->ref <= 0);
4250
4251
4252 probe->ref--;
4253
4254 if (!probe->ref) {
4255 probe_ops = probe->probe_ops;
4256
4257
4258
4259
4260 if (probe_ops->free)
4261 probe_ops->free(probe_ops, probe->tr, 0, probe->data);
4262 list_del(&probe->list);
4263 kfree(probe);
4264 }
4265 mutex_unlock(&ftrace_lock);
4266}
4267
4268static void acquire_probe_locked(struct ftrace_func_probe *probe)
4269{
4270
4271
4272
4273
4274 probe->ref++;
4275}
4276
4277int
4278register_ftrace_function_probe(char *glob, struct trace_array *tr,
4279 struct ftrace_probe_ops *probe_ops,
4280 void *data)
4281{
4282 struct ftrace_func_entry *entry;
4283 struct ftrace_func_probe *probe;
4284 struct ftrace_hash **orig_hash;
4285 struct ftrace_hash *old_hash;
4286 struct ftrace_hash *hash;
4287 int count = 0;
4288 int size;
4289 int ret;
4290 int i;
4291
4292 if (WARN_ON(!tr))
4293 return -EINVAL;
4294
4295
4296 if (WARN_ON(glob[0] == '!'))
4297 return -EINVAL;
4298
4299
4300 mutex_lock(&ftrace_lock);
4301
4302 list_for_each_entry(probe, &tr->func_probes, list) {
4303 if (probe->probe_ops == probe_ops)
4304 break;
4305 }
4306 if (&probe->list == &tr->func_probes) {
4307 probe = kzalloc(sizeof(*probe), GFP_KERNEL);
4308 if (!probe) {
4309 mutex_unlock(&ftrace_lock);
4310 return -ENOMEM;
4311 }
4312 probe->probe_ops = probe_ops;
4313 probe->ops.func = function_trace_probe_call;
4314 probe->tr = tr;
4315 ftrace_ops_init(&probe->ops);
4316 list_add(&probe->list, &tr->func_probes);
4317 }
4318
4319 acquire_probe_locked(probe);
4320
4321 mutex_unlock(&ftrace_lock);
4322
4323 mutex_lock(&probe->ops.func_hash->regex_lock);
4324
4325 orig_hash = &probe->ops.func_hash->filter_hash;
4326 old_hash = *orig_hash;
4327 hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash);
4328
4329 ret = ftrace_match_records(hash, glob, strlen(glob));
4330
4331
4332 if (!ret)
4333 ret = -EINVAL;
4334
4335 if (ret < 0)
4336 goto out;
4337
4338 size = 1 << hash->size_bits;
4339 for (i = 0; i < size; i++) {
4340 hlist_for_each_entry(entry, &hash->buckets[i], hlist) {
4341 if (ftrace_lookup_ip(old_hash, entry->ip))
4342 continue;
4343
4344
4345
4346
4347
4348 if (probe_ops->init) {
4349 ret = probe_ops->init(probe_ops, tr,
4350 entry->ip, data,
4351 &probe->data);
4352 if (ret < 0) {
4353 if (probe_ops->free && count)
4354 probe_ops->free(probe_ops, tr,
4355 0, probe->data);
4356 probe->data = NULL;
4357 goto out;
4358 }
4359 }
4360 count++;
4361 }
4362 }
4363
4364 mutex_lock(&ftrace_lock);
4365
4366 if (!count) {
4367
4368 ret = -EINVAL;
4369 goto out_unlock;
4370 }
4371
4372 ret = ftrace_hash_move_and_update_ops(&probe->ops, orig_hash,
4373 hash, 1);
4374 if (ret < 0)
4375 goto err_unlock;
4376
4377
4378 probe->ref += count;
4379
4380 if (!(probe->ops.flags & FTRACE_OPS_FL_ENABLED))
4381 ret = ftrace_startup(&probe->ops, 0);
4382
4383 out_unlock:
4384 mutex_unlock(&ftrace_lock);
4385
4386 if (!ret)
4387 ret = count;
4388 out:
4389 mutex_unlock(&probe->ops.func_hash->regex_lock);
4390 free_ftrace_hash(hash);
4391
4392 release_probe(probe);
4393
4394 return ret;
4395
4396 err_unlock:
4397 if (!probe_ops->free || !count)
4398 goto out_unlock;
4399
4400
4401 for (i = 0; i < size; i++) {
4402 hlist_for_each_entry(entry, &hash->buckets[i], hlist) {
4403 if (ftrace_lookup_ip(old_hash, entry->ip))
4404 continue;
4405 probe_ops->free(probe_ops, tr, entry->ip, probe->data);
4406 }
4407 }
4408 goto out_unlock;
4409}
4410
4411int
4412unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
4413 struct ftrace_probe_ops *probe_ops)
4414{
4415 struct ftrace_ops_hash old_hash_ops;
4416 struct ftrace_func_entry *entry;
4417 struct ftrace_func_probe *probe;
4418 struct ftrace_glob func_g;
4419 struct ftrace_hash **orig_hash;
4420 struct ftrace_hash *old_hash;
4421 struct ftrace_hash *hash = NULL;
4422 struct hlist_node *tmp;
4423 struct hlist_head hhd;
4424 char str[KSYM_SYMBOL_LEN];
4425 int count = 0;
4426 int i, ret = -ENODEV;
4427 int size;
4428
4429 if (!glob || !strlen(glob) || !strcmp(glob, "*"))
4430 func_g.search = NULL;
4431 else {
4432 int not;
4433
4434 func_g.type = filter_parse_regex(glob, strlen(glob),
4435 &func_g.search, ¬);
4436 func_g.len = strlen(func_g.search);
4437
4438
4439 if (WARN_ON(not))
4440 return -EINVAL;
4441 }
4442
4443 mutex_lock(&ftrace_lock);
4444
4445 list_for_each_entry(probe, &tr->func_probes, list) {
4446 if (probe->probe_ops == probe_ops)
4447 break;
4448 }
4449 if (&probe->list == &tr->func_probes)
4450 goto err_unlock_ftrace;
4451
4452 ret = -EINVAL;
4453 if (!(probe->ops.flags & FTRACE_OPS_FL_INITIALIZED))
4454 goto err_unlock_ftrace;
4455
4456 acquire_probe_locked(probe);
4457
4458 mutex_unlock(&ftrace_lock);
4459
4460 mutex_lock(&probe->ops.func_hash->regex_lock);
4461
4462 orig_hash = &probe->ops.func_hash->filter_hash;
4463 old_hash = *orig_hash;
4464
4465 if (ftrace_hash_empty(old_hash))
4466 goto out_unlock;
4467
4468 old_hash_ops.filter_hash = old_hash;
4469
4470 old_hash_ops.notrace_hash = NULL;
4471
4472 ret = -ENOMEM;
4473 hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, old_hash);
4474 if (!hash)
4475 goto out_unlock;
4476
4477 INIT_HLIST_HEAD(&hhd);
4478
4479 size = 1 << hash->size_bits;
4480 for (i = 0; i < size; i++) {
4481 hlist_for_each_entry_safe(entry, tmp, &hash->buckets[i], hlist) {
4482
4483 if (func_g.search) {
4484 kallsyms_lookup(entry->ip, NULL, NULL,
4485 NULL, str);
4486 if (!ftrace_match(str, &func_g))
4487 continue;
4488 }
4489 count++;
4490 remove_hash_entry(hash, entry);
4491 hlist_add_head(&entry->hlist, &hhd);
4492 }
4493 }
4494
4495
4496 if (!count) {
4497 ret = -EINVAL;
4498 goto out_unlock;
4499 }
4500
4501 mutex_lock(&ftrace_lock);
4502
4503 WARN_ON(probe->ref < count);
4504
4505 probe->ref -= count;
4506
4507 if (ftrace_hash_empty(hash))
4508 ftrace_shutdown(&probe->ops, 0);
4509
4510 ret = ftrace_hash_move_and_update_ops(&probe->ops, orig_hash,
4511 hash, 1);
4512
4513
4514 if (ftrace_enabled && !ftrace_hash_empty(hash))
4515 ftrace_run_modify_code(&probe->ops, FTRACE_UPDATE_CALLS,
4516 &old_hash_ops);
4517 synchronize_rcu();
4518
4519 hlist_for_each_entry_safe(entry, tmp, &hhd, hlist) {
4520 hlist_del(&entry->hlist);
4521 if (probe_ops->free)
4522 probe_ops->free(probe_ops, tr, entry->ip, probe->data);
4523 kfree(entry);
4524 }
4525 mutex_unlock(&ftrace_lock);
4526
4527 out_unlock:
4528 mutex_unlock(&probe->ops.func_hash->regex_lock);
4529 free_ftrace_hash(hash);
4530
4531 release_probe(probe);
4532
4533 return ret;
4534
4535 err_unlock_ftrace:
4536 mutex_unlock(&ftrace_lock);
4537 return ret;
4538}
4539
4540void clear_ftrace_function_probes(struct trace_array *tr)
4541{
4542 struct ftrace_func_probe *probe, *n;
4543
4544 list_for_each_entry_safe(probe, n, &tr->func_probes, list)
4545 unregister_ftrace_function_probe_func(NULL, tr, probe->probe_ops);
4546}
4547
4548static LIST_HEAD(ftrace_commands);
4549static DEFINE_MUTEX(ftrace_cmd_mutex);
4550
4551
4552
4553
4554
4555__init int register_ftrace_command(struct ftrace_func_command *cmd)
4556{
4557 struct ftrace_func_command *p;
4558 int ret = 0;
4559
4560 mutex_lock(&ftrace_cmd_mutex);
4561 list_for_each_entry(p, &ftrace_commands, list) {
4562 if (strcmp(cmd->name, p->name) == 0) {
4563 ret = -EBUSY;
4564 goto out_unlock;
4565 }
4566 }
4567 list_add(&cmd->list, &ftrace_commands);
4568 out_unlock:
4569 mutex_unlock(&ftrace_cmd_mutex);
4570
4571 return ret;
4572}
4573
4574
4575
4576
4577
4578__init int unregister_ftrace_command(struct ftrace_func_command *cmd)
4579{
4580 struct ftrace_func_command *p, *n;
4581 int ret = -ENODEV;
4582
4583 mutex_lock(&ftrace_cmd_mutex);
4584 list_for_each_entry_safe(p, n, &ftrace_commands, list) {
4585 if (strcmp(cmd->name, p->name) == 0) {
4586 ret = 0;
4587 list_del_init(&p->list);
4588 goto out_unlock;
4589 }
4590 }
4591 out_unlock:
4592 mutex_unlock(&ftrace_cmd_mutex);
4593
4594 return ret;
4595}
4596
4597static int ftrace_process_regex(struct ftrace_iterator *iter,
4598 char *buff, int len, int enable)
4599{
4600 struct ftrace_hash *hash = iter->hash;
4601 struct trace_array *tr = iter->ops->private;
4602 char *func, *command, *next = buff;
4603 struct ftrace_func_command *p;
4604 int ret = -EINVAL;
4605
4606 func = strsep(&next, ":");
4607
4608 if (!next) {
4609 ret = ftrace_match_records(hash, func, len);
4610 if (!ret)
4611 ret = -EINVAL;
4612 if (ret < 0)
4613 return ret;
4614 return 0;
4615 }
4616
4617
4618
4619 command = strsep(&next, ":");
4620
4621 mutex_lock(&ftrace_cmd_mutex);
4622 list_for_each_entry(p, &ftrace_commands, list) {
4623 if (strcmp(p->name, command) == 0) {
4624 ret = p->func(tr, hash, func, command, next, enable);
4625 goto out_unlock;
4626 }
4627 }
4628 out_unlock:
4629 mutex_unlock(&ftrace_cmd_mutex);
4630
4631 return ret;
4632}
4633
4634static ssize_t
4635ftrace_regex_write(struct file *file, const char __user *ubuf,
4636 size_t cnt, loff_t *ppos, int enable)
4637{
4638 struct ftrace_iterator *iter;
4639 struct trace_parser *parser;
4640 ssize_t ret, read;
4641
4642 if (!cnt)
4643 return 0;
4644
4645 if (file->f_mode & FMODE_READ) {
4646 struct seq_file *m = file->private_data;
4647 iter = m->private;
4648 } else
4649 iter = file->private_data;
4650
4651 if (unlikely(ftrace_disabled))
4652 return -ENODEV;
4653
4654
4655
4656 parser = &iter->parser;
4657 read = trace_get_user(parser, ubuf, cnt, ppos);
4658
4659 if (read >= 0 && trace_parser_loaded(parser) &&
4660 !trace_parser_cont(parser)) {
4661 ret = ftrace_process_regex(iter, parser->buffer,
4662 parser->idx, enable);
4663 trace_parser_clear(parser);
4664 if (ret < 0)
4665 goto out;
4666 }
4667
4668 ret = read;
4669 out:
4670 return ret;
4671}
4672
4673ssize_t
4674ftrace_filter_write(struct file *file, const char __user *ubuf,
4675 size_t cnt, loff_t *ppos)
4676{
4677 return ftrace_regex_write(file, ubuf, cnt, ppos, 1);
4678}
4679
4680ssize_t
4681ftrace_notrace_write(struct file *file, const char __user *ubuf,
4682 size_t cnt, loff_t *ppos)
4683{
4684 return ftrace_regex_write(file, ubuf, cnt, ppos, 0);
4685}
4686
4687static int
4688ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove)
4689{
4690 struct ftrace_func_entry *entry;
4691
4692 if (!ftrace_location(ip))
4693 return -EINVAL;
4694
4695 if (remove) {
4696 entry = ftrace_lookup_ip(hash, ip);
4697 if (!entry)
4698 return -ENOENT;
4699 free_hash_entry(hash, entry);
4700 return 0;
4701 }
4702
4703 return add_hash_entry(hash, ip);
4704}
4705
4706static int
4707ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
4708 unsigned long ip, int remove, int reset, int enable)
4709{
4710 struct ftrace_hash **orig_hash;
4711 struct ftrace_hash *hash;
4712 int ret;
4713
4714 if (unlikely(ftrace_disabled))
4715 return -ENODEV;
4716
4717 mutex_lock(&ops->func_hash->regex_lock);
4718
4719 if (enable)
4720 orig_hash = &ops->func_hash->filter_hash;
4721 else
4722 orig_hash = &ops->func_hash->notrace_hash;
4723
4724 if (reset)
4725 hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS);
4726 else
4727 hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, *orig_hash);
4728
4729 if (!hash) {
4730 ret = -ENOMEM;
4731 goto out_regex_unlock;
4732 }
4733
4734 if (buf && !ftrace_match_records(hash, buf, len)) {
4735 ret = -EINVAL;
4736 goto out_regex_unlock;
4737 }
4738 if (ip) {
4739 ret = ftrace_match_addr(hash, ip, remove);
4740 if (ret < 0)
4741 goto out_regex_unlock;
4742 }
4743
4744 mutex_lock(&ftrace_lock);
4745 ret = ftrace_hash_move_and_update_ops(ops, orig_hash, hash, enable);
4746 mutex_unlock(&ftrace_lock);
4747
4748 out_regex_unlock:
4749 mutex_unlock(&ops->func_hash->regex_lock);
4750
4751 free_ftrace_hash(hash);
4752 return ret;
4753}
4754
4755static int
4756ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove,
4757 int reset, int enable)
4758{
4759 return ftrace_set_hash(ops, NULL, 0, ip, remove, reset, enable);
4760}
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip,
4773 int remove, int reset)
4774{
4775 ftrace_ops_init(ops);
4776 return ftrace_set_addr(ops, ip, remove, reset, 1);
4777}
4778EXPORT_SYMBOL_GPL(ftrace_set_filter_ip);
4779
4780
4781
4782
4783
4784
4785
4786
4787void ftrace_ops_set_global_filter(struct ftrace_ops *ops)
4788{
4789 if (ops->flags & FTRACE_OPS_FL_INITIALIZED)
4790 return;
4791
4792 ftrace_ops_init(ops);
4793 ops->func_hash = &global_ops.local_hash;
4794}
4795EXPORT_SYMBOL_GPL(ftrace_ops_set_global_filter);
4796
4797static int
4798ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
4799 int reset, int enable)
4800{
4801 return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable);
4802}
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
4815 int len, int reset)
4816{
4817 ftrace_ops_init(ops);
4818 return ftrace_set_regex(ops, buf, len, reset, 1);
4819}
4820EXPORT_SYMBOL_GPL(ftrace_set_filter);
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
4834 int len, int reset)
4835{
4836 ftrace_ops_init(ops);
4837 return ftrace_set_regex(ops, buf, len, reset, 0);
4838}
4839EXPORT_SYMBOL_GPL(ftrace_set_notrace);
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849void ftrace_set_global_filter(unsigned char *buf, int len, int reset)
4850{
4851 ftrace_set_regex(&global_ops, buf, len, reset, 1);
4852}
4853EXPORT_SYMBOL_GPL(ftrace_set_global_filter);
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865void ftrace_set_global_notrace(unsigned char *buf, int len, int reset)
4866{
4867 ftrace_set_regex(&global_ops, buf, len, reset, 0);
4868}
4869EXPORT_SYMBOL_GPL(ftrace_set_global_notrace);
4870
4871
4872
4873
4874#define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE
4875static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata;
4876static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata;
4877
4878
4879bool ftrace_filter_param __initdata;
4880
4881static int __init set_ftrace_notrace(char *str)
4882{
4883 ftrace_filter_param = true;
4884 strlcpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE);
4885 return 1;
4886}
4887__setup("ftrace_notrace=", set_ftrace_notrace);
4888
4889static int __init set_ftrace_filter(char *str)
4890{
4891 ftrace_filter_param = true;
4892 strlcpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE);
4893 return 1;
4894}
4895__setup("ftrace_filter=", set_ftrace_filter);
4896
4897#ifdef CONFIG_FUNCTION_GRAPH_TRACER
4898static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata;
4899static char ftrace_graph_notrace_buf[FTRACE_FILTER_SIZE] __initdata;
4900static int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer);
4901
4902static int __init set_graph_function(char *str)
4903{
4904 strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE);
4905 return 1;
4906}
4907__setup("ftrace_graph_filter=", set_graph_function);
4908
4909static int __init set_graph_notrace_function(char *str)
4910{
4911 strlcpy(ftrace_graph_notrace_buf, str, FTRACE_FILTER_SIZE);
4912 return 1;
4913}
4914__setup("ftrace_graph_notrace=", set_graph_notrace_function);
4915
4916static int __init set_graph_max_depth_function(char *str)
4917{
4918 if (!str)
4919 return 0;
4920 fgraph_max_depth = simple_strtoul(str, NULL, 0);
4921 return 1;
4922}
4923__setup("ftrace_graph_max_depth=", set_graph_max_depth_function);
4924
4925static void __init set_ftrace_early_graph(char *buf, int enable)
4926{
4927 int ret;
4928 char *func;
4929 struct ftrace_hash *hash;
4930
4931 hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS);
4932 if (WARN_ON(!hash))
4933 return;
4934
4935 while (buf) {
4936 func = strsep(&buf, ",");
4937
4938 ret = ftrace_graph_set_hash(hash, func);
4939 if (ret)
4940 printk(KERN_DEBUG "ftrace: function %s not "
4941 "traceable\n", func);
4942 }
4943
4944 if (enable)
4945 ftrace_graph_hash = hash;
4946 else
4947 ftrace_graph_notrace_hash = hash;
4948}
4949#endif
4950
4951void __init
4952ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable)
4953{
4954 char *func;
4955
4956 ftrace_ops_init(ops);
4957
4958 while (buf) {
4959 func = strsep(&buf, ",");
4960 ftrace_set_regex(ops, func, strlen(func), 0, enable);
4961 }
4962}
4963
4964static void __init set_ftrace_early_filters(void)
4965{
4966 if (ftrace_filter_buf[0])
4967 ftrace_set_early_filter(&global_ops, ftrace_filter_buf, 1);
4968 if (ftrace_notrace_buf[0])
4969 ftrace_set_early_filter(&global_ops, ftrace_notrace_buf, 0);
4970#ifdef CONFIG_FUNCTION_GRAPH_TRACER
4971 if (ftrace_graph_buf[0])
4972 set_ftrace_early_graph(ftrace_graph_buf, 1);
4973 if (ftrace_graph_notrace_buf[0])
4974 set_ftrace_early_graph(ftrace_graph_notrace_buf, 0);
4975#endif
4976}
4977
4978int ftrace_regex_release(struct inode *inode, struct file *file)
4979{
4980 struct seq_file *m = (struct seq_file *)file->private_data;
4981 struct ftrace_iterator *iter;
4982 struct ftrace_hash **orig_hash;
4983 struct trace_parser *parser;
4984 int filter_hash;
4985 int ret;
4986
4987 if (file->f_mode & FMODE_READ) {
4988 iter = m->private;
4989 seq_release(inode, file);
4990 } else
4991 iter = file->private_data;
4992
4993 parser = &iter->parser;
4994 if (trace_parser_loaded(parser)) {
4995 ftrace_match_records(iter->hash, parser->buffer, parser->idx);
4996 }
4997
4998 trace_parser_put(parser);
4999
5000 mutex_lock(&iter->ops->func_hash->regex_lock);
5001
5002 if (file->f_mode & FMODE_WRITE) {
5003 filter_hash = !!(iter->flags & FTRACE_ITER_FILTER);
5004
5005 if (filter_hash) {
5006 orig_hash = &iter->ops->func_hash->filter_hash;
5007 if (iter->tr && !list_empty(&iter->tr->mod_trace))
5008 iter->hash->flags |= FTRACE_HASH_FL_MOD;
5009 } else
5010 orig_hash = &iter->ops->func_hash->notrace_hash;
5011
5012 mutex_lock(&ftrace_lock);
5013 ret = ftrace_hash_move_and_update_ops(iter->ops, orig_hash,
5014 iter->hash, filter_hash);
5015 mutex_unlock(&ftrace_lock);
5016 } else {
5017
5018 iter->hash = NULL;
5019 }
5020
5021 mutex_unlock(&iter->ops->func_hash->regex_lock);
5022 free_ftrace_hash(iter->hash);
5023 kfree(iter);
5024
5025 return 0;
5026}
5027
5028static const struct file_operations ftrace_avail_fops = {
5029 .open = ftrace_avail_open,
5030 .read = seq_read,
5031 .llseek = seq_lseek,
5032 .release = seq_release_private,
5033};
5034
5035static const struct file_operations ftrace_enabled_fops = {
5036 .open = ftrace_enabled_open,
5037 .read = seq_read,
5038 .llseek = seq_lseek,
5039 .release = seq_release_private,
5040};
5041
5042static const struct file_operations ftrace_filter_fops = {
5043 .open = ftrace_filter_open,
5044 .read = seq_read,
5045 .write = ftrace_filter_write,
5046 .llseek = tracing_lseek,
5047 .release = ftrace_regex_release,
5048};
5049
5050static const struct file_operations ftrace_notrace_fops = {
5051 .open = ftrace_notrace_open,
5052 .read = seq_read,
5053 .write = ftrace_notrace_write,
5054 .llseek = tracing_lseek,
5055 .release = ftrace_regex_release,
5056};
5057
5058#ifdef CONFIG_FUNCTION_GRAPH_TRACER
5059
5060static DEFINE_MUTEX(graph_lock);
5061
5062struct ftrace_hash *ftrace_graph_hash = EMPTY_HASH;
5063struct ftrace_hash *ftrace_graph_notrace_hash = EMPTY_HASH;
5064
5065enum graph_filter_type {
5066 GRAPH_FILTER_NOTRACE = 0,
5067 GRAPH_FILTER_FUNCTION,
5068};
5069
5070#define FTRACE_GRAPH_EMPTY ((void *)1)
5071
5072struct ftrace_graph_data {
5073 struct ftrace_hash *hash;
5074 struct ftrace_func_entry *entry;
5075 int idx;
5076 enum graph_filter_type type;
5077 struct ftrace_hash *new_hash;
5078 const struct seq_operations *seq_ops;
5079 struct trace_parser parser;
5080};
5081
5082static void *
5083__g_next(struct seq_file *m, loff_t *pos)
5084{
5085 struct ftrace_graph_data *fgd = m->private;
5086 struct ftrace_func_entry *entry = fgd->entry;
5087 struct hlist_head *head;
5088 int i, idx = fgd->idx;
5089
5090 if (*pos >= fgd->hash->count)
5091 return NULL;
5092
5093 if (entry) {
5094 hlist_for_each_entry_continue(entry, hlist) {
5095 fgd->entry = entry;
5096 return entry;
5097 }
5098
5099 idx++;
5100 }
5101
5102 for (i = idx; i < 1 << fgd->hash->size_bits; i++) {
5103 head = &fgd->hash->buckets[i];
5104 hlist_for_each_entry(entry, head, hlist) {
5105 fgd->entry = entry;
5106 fgd->idx = i;
5107 return entry;
5108 }
5109 }
5110 return NULL;
5111}
5112
5113static void *
5114g_next(struct seq_file *m, void *v, loff_t *pos)
5115{
5116 (*pos)++;
5117 return __g_next(m, pos);
5118}
5119
5120static void *g_start(struct seq_file *m, loff_t *pos)
5121{
5122 struct ftrace_graph_data *fgd = m->private;
5123
5124 mutex_lock(&graph_lock);
5125
5126 if (fgd->type == GRAPH_FILTER_FUNCTION)
5127 fgd->hash = rcu_dereference_protected(ftrace_graph_hash,
5128 lockdep_is_held(&graph_lock));
5129 else
5130 fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
5131 lockdep_is_held(&graph_lock));
5132
5133
5134 if (ftrace_hash_empty(fgd->hash) && !*pos)
5135 return FTRACE_GRAPH_EMPTY;
5136
5137 fgd->idx = 0;
5138 fgd->entry = NULL;
5139 return __g_next(m, pos);
5140}
5141
5142static void g_stop(struct seq_file *m, void *p)
5143{
5144 mutex_unlock(&graph_lock);
5145}
5146
5147static int g_show(struct seq_file *m, void *v)
5148{
5149 struct ftrace_func_entry *entry = v;
5150
5151 if (!entry)
5152 return 0;
5153
5154 if (entry == FTRACE_GRAPH_EMPTY) {
5155 struct ftrace_graph_data *fgd = m->private;
5156
5157 if (fgd->type == GRAPH_FILTER_FUNCTION)
5158 seq_puts(m, "#### all functions enabled ####\n");
5159 else
5160 seq_puts(m, "#### no functions disabled ####\n");
5161 return 0;
5162 }
5163
5164 seq_printf(m, "%ps\n", (void *)entry->ip);
5165
5166 return 0;
5167}
5168
5169static const struct seq_operations ftrace_graph_seq_ops = {
5170 .start = g_start,
5171 .next = g_next,
5172 .stop = g_stop,
5173 .show = g_show,
5174};
5175
5176static int
5177__ftrace_graph_open(struct inode *inode, struct file *file,
5178 struct ftrace_graph_data *fgd)
5179{
5180 int ret = 0;
5181 struct ftrace_hash *new_hash = NULL;
5182
5183 if (file->f_mode & FMODE_WRITE) {
5184 const int size_bits = FTRACE_HASH_DEFAULT_BITS;
5185
5186 if (trace_parser_get_init(&fgd->parser, FTRACE_BUFF_MAX))
5187 return -ENOMEM;
5188
5189 if (file->f_flags & O_TRUNC)
5190 new_hash = alloc_ftrace_hash(size_bits);
5191 else
5192 new_hash = alloc_and_copy_ftrace_hash(size_bits,
5193 fgd->hash);
5194 if (!new_hash) {
5195 ret = -ENOMEM;
5196 goto out;
5197 }
5198 }
5199
5200 if (file->f_mode & FMODE_READ) {
5201 ret = seq_open(file, &ftrace_graph_seq_ops);
5202 if (!ret) {
5203 struct seq_file *m = file->private_data;
5204 m->private = fgd;
5205 } else {
5206
5207 free_ftrace_hash(new_hash);
5208 new_hash = NULL;
5209 }
5210 } else
5211 file->private_data = fgd;
5212
5213out:
5214 if (ret < 0 && file->f_mode & FMODE_WRITE)
5215 trace_parser_put(&fgd->parser);
5216
5217 fgd->new_hash = new_hash;
5218
5219
5220
5221
5222
5223
5224 fgd->hash = NULL;
5225
5226 return ret;
5227}
5228
5229static int
5230ftrace_graph_open(struct inode *inode, struct file *file)
5231{
5232 struct ftrace_graph_data *fgd;
5233 int ret;
5234
5235 if (unlikely(ftrace_disabled))
5236 return -ENODEV;
5237
5238 fgd = kmalloc(sizeof(*fgd), GFP_KERNEL);
5239 if (fgd == NULL)
5240 return -ENOMEM;
5241
5242 mutex_lock(&graph_lock);
5243
5244 fgd->hash = rcu_dereference_protected(ftrace_graph_hash,
5245 lockdep_is_held(&graph_lock));
5246 fgd->type = GRAPH_FILTER_FUNCTION;
5247 fgd->seq_ops = &ftrace_graph_seq_ops;
5248
5249 ret = __ftrace_graph_open(inode, file, fgd);
5250 if (ret < 0)
5251 kfree(fgd);
5252
5253 mutex_unlock(&graph_lock);
5254 return ret;
5255}
5256
5257static int
5258ftrace_graph_notrace_open(struct inode *inode, struct file *file)
5259{
5260 struct ftrace_graph_data *fgd;
5261 int ret;
5262
5263 if (unlikely(ftrace_disabled))
5264 return -ENODEV;
5265
5266 fgd = kmalloc(sizeof(*fgd), GFP_KERNEL);
5267 if (fgd == NULL)
5268 return -ENOMEM;
5269
5270 mutex_lock(&graph_lock);
5271
5272 fgd->hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
5273 lockdep_is_held(&graph_lock));
5274 fgd->type = GRAPH_FILTER_NOTRACE;
5275 fgd->seq_ops = &ftrace_graph_seq_ops;
5276
5277 ret = __ftrace_graph_open(inode, file, fgd);
5278 if (ret < 0)
5279 kfree(fgd);
5280
5281 mutex_unlock(&graph_lock);
5282 return ret;
5283}
5284
5285static int
5286ftrace_graph_release(struct inode *inode, struct file *file)
5287{
5288 struct ftrace_graph_data *fgd;
5289 struct ftrace_hash *old_hash, *new_hash;
5290 struct trace_parser *parser;
5291 int ret = 0;
5292
5293 if (file->f_mode & FMODE_READ) {
5294 struct seq_file *m = file->private_data;
5295
5296 fgd = m->private;
5297 seq_release(inode, file);
5298 } else {
5299 fgd = file->private_data;
5300 }
5301
5302
5303 if (file->f_mode & FMODE_WRITE) {
5304
5305 parser = &fgd->parser;
5306
5307 if (trace_parser_loaded((parser))) {
5308 ret = ftrace_graph_set_hash(fgd->new_hash,
5309 parser->buffer);
5310 }
5311
5312 trace_parser_put(parser);
5313
5314 new_hash = __ftrace_hash_move(fgd->new_hash);
5315 if (!new_hash) {
5316 ret = -ENOMEM;
5317 goto out;
5318 }
5319
5320 mutex_lock(&graph_lock);
5321
5322 if (fgd->type == GRAPH_FILTER_FUNCTION) {
5323 old_hash = rcu_dereference_protected(ftrace_graph_hash,
5324 lockdep_is_held(&graph_lock));
5325 rcu_assign_pointer(ftrace_graph_hash, new_hash);
5326 } else {
5327 old_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
5328 lockdep_is_held(&graph_lock));
5329 rcu_assign_pointer(ftrace_graph_notrace_hash, new_hash);
5330 }
5331
5332 mutex_unlock(&graph_lock);
5333
5334
5335 synchronize_rcu();
5336
5337 free_ftrace_hash(old_hash);
5338 }
5339
5340 out:
5341 free_ftrace_hash(fgd->new_hash);
5342 kfree(fgd);
5343
5344 return ret;
5345}
5346
5347static int
5348ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer)
5349{
5350 struct ftrace_glob func_g;
5351 struct dyn_ftrace *rec;
5352 struct ftrace_page *pg;
5353 struct ftrace_func_entry *entry;
5354 int fail = 1;
5355 int not;
5356
5357
5358 func_g.type = filter_parse_regex(buffer, strlen(buffer),
5359 &func_g.search, ¬);
5360
5361 func_g.len = strlen(func_g.search);
5362
5363 mutex_lock(&ftrace_lock);
5364
5365 if (unlikely(ftrace_disabled)) {
5366 mutex_unlock(&ftrace_lock);
5367 return -ENODEV;
5368 }
5369
5370 do_for_each_ftrace_rec(pg, rec) {
5371
5372 if (rec->flags & FTRACE_FL_DISABLED)
5373 continue;
5374
5375 if (ftrace_match_record(rec, &func_g, NULL, 0)) {
5376 entry = ftrace_lookup_ip(hash, rec->ip);
5377
5378 if (!not) {
5379 fail = 0;
5380
5381 if (entry)
5382 continue;
5383 if (add_hash_entry(hash, rec->ip) < 0)
5384 goto out;
5385 } else {
5386 if (entry) {
5387 free_hash_entry(hash, entry);
5388 fail = 0;
5389 }
5390 }
5391 }
5392 } while_for_each_ftrace_rec();
5393out:
5394 mutex_unlock(&ftrace_lock);
5395
5396 if (fail)
5397 return -EINVAL;
5398
5399 return 0;
5400}
5401
5402static ssize_t
5403ftrace_graph_write(struct file *file, const char __user *ubuf,
5404 size_t cnt, loff_t *ppos)
5405{
5406 ssize_t read, ret = 0;
5407 struct ftrace_graph_data *fgd = file->private_data;
5408 struct trace_parser *parser;
5409
5410 if (!cnt)
5411 return 0;
5412
5413
5414 if (file->f_mode & FMODE_READ) {
5415 struct seq_file *m = file->private_data;
5416 fgd = m->private;
5417 }
5418
5419 parser = &fgd->parser;
5420
5421 read = trace_get_user(parser, ubuf, cnt, ppos);
5422
5423 if (read >= 0 && trace_parser_loaded(parser) &&
5424 !trace_parser_cont(parser)) {
5425
5426 ret = ftrace_graph_set_hash(fgd->new_hash,
5427 parser->buffer);
5428 trace_parser_clear(parser);
5429 }
5430
5431 if (!ret)
5432 ret = read;
5433
5434 return ret;
5435}
5436
5437static const struct file_operations ftrace_graph_fops = {
5438 .open = ftrace_graph_open,
5439 .read = seq_read,
5440 .write = ftrace_graph_write,
5441 .llseek = tracing_lseek,
5442 .release = ftrace_graph_release,
5443};
5444
5445static const struct file_operations ftrace_graph_notrace_fops = {
5446 .open = ftrace_graph_notrace_open,
5447 .read = seq_read,
5448 .write = ftrace_graph_write,
5449 .llseek = tracing_lseek,
5450 .release = ftrace_graph_release,
5451};
5452#endif
5453
5454void ftrace_create_filter_files(struct ftrace_ops *ops,
5455 struct dentry *parent)
5456{
5457
5458 trace_create_file("set_ftrace_filter", 0644, parent,
5459 ops, &ftrace_filter_fops);
5460
5461 trace_create_file("set_ftrace_notrace", 0644, parent,
5462 ops, &ftrace_notrace_fops);
5463}
5464
5465
5466
5467
5468
5469
5470
5471
5472
5473
5474
5475void ftrace_destroy_filter_files(struct ftrace_ops *ops)
5476{
5477 mutex_lock(&ftrace_lock);
5478 if (ops->flags & FTRACE_OPS_FL_ENABLED)
5479 ftrace_shutdown(ops, 0);
5480 ops->flags |= FTRACE_OPS_FL_DELETED;
5481 ftrace_free_filter(ops);
5482 mutex_unlock(&ftrace_lock);
5483}
5484
5485static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer)
5486{
5487
5488 trace_create_file("available_filter_functions", 0444,
5489 d_tracer, NULL, &ftrace_avail_fops);
5490
5491 trace_create_file("enabled_functions", 0444,
5492 d_tracer, NULL, &ftrace_enabled_fops);
5493
5494 ftrace_create_filter_files(&global_ops, d_tracer);
5495
5496#ifdef CONFIG_FUNCTION_GRAPH_TRACER
5497 trace_create_file("set_graph_function", 0644, d_tracer,
5498 NULL,
5499 &ftrace_graph_fops);
5500 trace_create_file("set_graph_notrace", 0644, d_tracer,
5501 NULL,
5502 &ftrace_graph_notrace_fops);
5503#endif
5504
5505 return 0;
5506}
5507
5508static int ftrace_cmp_ips(const void *a, const void *b)
5509{
5510 const unsigned long *ipa = a;
5511 const unsigned long *ipb = b;
5512
5513 if (*ipa > *ipb)
5514 return 1;
5515 if (*ipa < *ipb)
5516 return -1;
5517 return 0;
5518}
5519
5520static int ftrace_process_locs(struct module *mod,
5521 unsigned long *start,
5522 unsigned long *end)
5523{
5524 struct ftrace_page *start_pg;
5525 struct ftrace_page *pg;
5526 struct dyn_ftrace *rec;
5527 unsigned long count;
5528 unsigned long *p;
5529 unsigned long addr;
5530 unsigned long flags = 0;
5531 int ret = -ENOMEM;
5532
5533 count = end - start;
5534
5535 if (!count)
5536 return 0;
5537
5538 sort(start, count, sizeof(*start),
5539 ftrace_cmp_ips, NULL);
5540
5541 start_pg = ftrace_allocate_pages(count);
5542 if (!start_pg)
5543 return -ENOMEM;
5544
5545 mutex_lock(&ftrace_lock);
5546
5547
5548
5549
5550
5551
5552 if (!mod) {
5553 WARN_ON(ftrace_pages || ftrace_pages_start);
5554
5555 ftrace_pages = ftrace_pages_start = start_pg;
5556 } else {
5557 if (!ftrace_pages)
5558 goto out;
5559
5560 if (WARN_ON(ftrace_pages->next)) {
5561
5562 while (ftrace_pages->next)
5563 ftrace_pages = ftrace_pages->next;
5564 }
5565
5566 ftrace_pages->next = start_pg;
5567 }
5568
5569 p = start;
5570 pg = start_pg;
5571 while (p < end) {
5572 addr = ftrace_call_adjust(*p++);
5573
5574
5575
5576
5577
5578
5579 if (!addr)
5580 continue;
5581
5582 if (pg->index == pg->size) {
5583
5584 if (WARN_ON(!pg->next))
5585 break;
5586 pg = pg->next;
5587 }
5588
5589 rec = &pg->records[pg->index++];
5590 rec->ip = addr;
5591 }
5592
5593
5594 WARN_ON(pg->next);
5595
5596
5597 ftrace_pages = pg;
5598
5599
5600
5601
5602
5603
5604
5605
5606
5607 if (!mod)
5608 local_irq_save(flags);
5609 ftrace_update_code(mod, start_pg);
5610 if (!mod)
5611 local_irq_restore(flags);
5612 ret = 0;
5613 out:
5614 mutex_unlock(&ftrace_lock);
5615
5616 return ret;
5617}
5618
5619struct ftrace_mod_func {
5620 struct list_head list;
5621 char *name;
5622 unsigned long ip;
5623 unsigned int size;
5624};
5625
5626struct ftrace_mod_map {
5627 struct rcu_head rcu;
5628 struct list_head list;
5629 struct module *mod;
5630 unsigned long start_addr;
5631 unsigned long end_addr;
5632 struct list_head funcs;
5633 unsigned int num_funcs;
5634};
5635
5636#ifdef CONFIG_MODULES
5637
5638#define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next)
5639
5640static LIST_HEAD(ftrace_mod_maps);
5641
5642static int referenced_filters(struct dyn_ftrace *rec)
5643{
5644 struct ftrace_ops *ops;
5645 int cnt = 0;
5646
5647 for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) {
5648 if (ops_references_rec(ops, rec))
5649 cnt++;
5650 }
5651
5652 return cnt;
5653}
5654
5655static void
5656clear_mod_from_hash(struct ftrace_page *pg, struct ftrace_hash *hash)
5657{
5658 struct ftrace_func_entry *entry;
5659 struct dyn_ftrace *rec;
5660 int i;
5661
5662 if (ftrace_hash_empty(hash))
5663 return;
5664
5665 for (i = 0; i < pg->index; i++) {
5666 rec = &pg->records[i];
5667 entry = __ftrace_lookup_ip(hash, rec->ip);
5668
5669
5670
5671
5672
5673 if (entry)
5674 entry->ip = 0;
5675 }
5676}
5677
5678
5679static void clear_mod_from_hashes(struct ftrace_page *pg)
5680{
5681 struct trace_array *tr;
5682
5683 mutex_lock(&trace_types_lock);
5684 list_for_each_entry(tr, &ftrace_trace_arrays, list) {
5685 if (!tr->ops || !tr->ops->func_hash)
5686 continue;
5687 mutex_lock(&tr->ops->func_hash->regex_lock);
5688 clear_mod_from_hash(pg, tr->ops->func_hash->filter_hash);
5689 clear_mod_from_hash(pg, tr->ops->func_hash->notrace_hash);
5690 mutex_unlock(&tr->ops->func_hash->regex_lock);
5691 }
5692 mutex_unlock(&trace_types_lock);
5693}
5694
5695static void ftrace_free_mod_map(struct rcu_head *rcu)
5696{
5697 struct ftrace_mod_map *mod_map = container_of(rcu, struct ftrace_mod_map, rcu);
5698 struct ftrace_mod_func *mod_func;
5699 struct ftrace_mod_func *n;
5700
5701
5702 list_for_each_entry_safe(mod_func, n, &mod_map->funcs, list) {
5703 kfree(mod_func->name);
5704 list_del(&mod_func->list);
5705 kfree(mod_func);
5706 }
5707
5708 kfree(mod_map);
5709}
5710
5711void ftrace_release_mod(struct module *mod)
5712{
5713 struct ftrace_mod_map *mod_map;
5714 struct ftrace_mod_map *n;
5715 struct dyn_ftrace *rec;
5716 struct ftrace_page **last_pg;
5717 struct ftrace_page *tmp_page = NULL;
5718 struct ftrace_page *pg;
5719 int order;
5720
5721 mutex_lock(&ftrace_lock);
5722
5723 if (ftrace_disabled)
5724 goto out_unlock;
5725
5726 list_for_each_entry_safe(mod_map, n, &ftrace_mod_maps, list) {
5727 if (mod_map->mod == mod) {
5728 list_del_rcu(&mod_map->list);
5729 call_rcu(&mod_map->rcu, ftrace_free_mod_map);
5730 break;
5731 }
5732 }
5733
5734
5735
5736
5737
5738 last_pg = &ftrace_pages_start;
5739 for (pg = ftrace_pages_start; pg; pg = *last_pg) {
5740 rec = &pg->records[0];
5741 if (within_module_core(rec->ip, mod) ||
5742 within_module_init(rec->ip, mod)) {
5743
5744
5745
5746
5747 if (WARN_ON(pg == ftrace_pages_start))
5748 goto out_unlock;
5749
5750
5751 if (pg == ftrace_pages)
5752 ftrace_pages = next_to_ftrace_page(last_pg);
5753
5754 ftrace_update_tot_cnt -= pg->index;
5755 *last_pg = pg->next;
5756
5757 pg->next = tmp_page;
5758 tmp_page = pg;
5759 } else
5760 last_pg = &pg->next;
5761 }
5762 out_unlock:
5763 mutex_unlock(&ftrace_lock);
5764
5765 for (pg = tmp_page; pg; pg = tmp_page) {
5766
5767
5768 clear_mod_from_hashes(pg);
5769
5770 order = get_count_order(pg->size / ENTRIES_PER_PAGE);
5771 free_pages((unsigned long)pg->records, order);
5772 tmp_page = pg->next;
5773 kfree(pg);
5774 }
5775}
5776
5777void ftrace_module_enable(struct module *mod)
5778{
5779 struct dyn_ftrace *rec;
5780 struct ftrace_page *pg;
5781
5782 mutex_lock(&ftrace_lock);
5783
5784 if (ftrace_disabled)
5785 goto out_unlock;
5786
5787
5788
5789
5790
5791
5792
5793
5794
5795
5796
5797
5798
5799
5800 if (ftrace_start_up)
5801 ftrace_arch_code_modify_prepare();
5802
5803 do_for_each_ftrace_rec(pg, rec) {
5804 int cnt;
5805
5806
5807
5808
5809
5810
5811 if (!within_module_core(rec->ip, mod) &&
5812 !within_module_init(rec->ip, mod))
5813 break;
5814
5815 cnt = 0;
5816
5817
5818
5819
5820
5821
5822
5823 if (ftrace_start_up)
5824 cnt += referenced_filters(rec);
5825
5826
5827 rec->flags = cnt;
5828
5829 if (ftrace_start_up && cnt) {
5830 int failed = __ftrace_replace_code(rec, 1);
5831 if (failed) {
5832 ftrace_bug(failed, rec);
5833 goto out_loop;
5834 }
5835 }
5836
5837 } while_for_each_ftrace_rec();
5838
5839 out_loop:
5840 if (ftrace_start_up)
5841 ftrace_arch_code_modify_post_process();
5842
5843 out_unlock:
5844 mutex_unlock(&ftrace_lock);
5845
5846 process_cached_mods(mod->name);
5847}
5848
5849void ftrace_module_init(struct module *mod)
5850{
5851 if (ftrace_disabled || !mod->num_ftrace_callsites)
5852 return;
5853
5854 ftrace_process_locs(mod, mod->ftrace_callsites,
5855 mod->ftrace_callsites + mod->num_ftrace_callsites);
5856}
5857
5858static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map,
5859 struct dyn_ftrace *rec)
5860{
5861 struct ftrace_mod_func *mod_func;
5862 unsigned long symsize;
5863 unsigned long offset;
5864 char str[KSYM_SYMBOL_LEN];
5865 char *modname;
5866 const char *ret;
5867
5868 ret = kallsyms_lookup(rec->ip, &symsize, &offset, &modname, str);
5869 if (!ret)
5870 return;
5871
5872 mod_func = kmalloc(sizeof(*mod_func), GFP_KERNEL);
5873 if (!mod_func)
5874 return;
5875
5876 mod_func->name = kstrdup(str, GFP_KERNEL);
5877 if (!mod_func->name) {
5878 kfree(mod_func);
5879 return;
5880 }
5881
5882 mod_func->ip = rec->ip - offset;
5883 mod_func->size = symsize;
5884
5885 mod_map->num_funcs++;
5886
5887 list_add_rcu(&mod_func->list, &mod_map->funcs);
5888}
5889
5890static struct ftrace_mod_map *
5891allocate_ftrace_mod_map(struct module *mod,
5892 unsigned long start, unsigned long end)
5893{
5894 struct ftrace_mod_map *mod_map;
5895
5896 mod_map = kmalloc(sizeof(*mod_map), GFP_KERNEL);
5897 if (!mod_map)
5898 return NULL;
5899
5900 mod_map->mod = mod;
5901 mod_map->start_addr = start;
5902 mod_map->end_addr = end;
5903 mod_map->num_funcs = 0;
5904
5905 INIT_LIST_HEAD_RCU(&mod_map->funcs);
5906
5907 list_add_rcu(&mod_map->list, &ftrace_mod_maps);
5908
5909 return mod_map;
5910}
5911
5912static const char *
5913ftrace_func_address_lookup(struct ftrace_mod_map *mod_map,
5914 unsigned long addr, unsigned long *size,
5915 unsigned long *off, char *sym)
5916{
5917 struct ftrace_mod_func *found_func = NULL;
5918 struct ftrace_mod_func *mod_func;
5919
5920 list_for_each_entry_rcu(mod_func, &mod_map->funcs, list) {
5921 if (addr >= mod_func->ip &&
5922 addr < mod_func->ip + mod_func->size) {
5923 found_func = mod_func;
5924 break;
5925 }
5926 }
5927
5928 if (found_func) {
5929 if (size)
5930 *size = found_func->size;
5931 if (off)
5932 *off = addr - found_func->ip;
5933 if (sym)
5934 strlcpy(sym, found_func->name, KSYM_NAME_LEN);
5935
5936 return found_func->name;
5937 }
5938
5939 return NULL;
5940}
5941
5942const char *
5943ftrace_mod_address_lookup(unsigned long addr, unsigned long *size,
5944 unsigned long *off, char **modname, char *sym)
5945{
5946 struct ftrace_mod_map *mod_map;
5947 const char *ret = NULL;
5948
5949
5950 preempt_disable();
5951 list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) {
5952 ret = ftrace_func_address_lookup(mod_map, addr, size, off, sym);
5953 if (ret) {
5954 if (modname)
5955 *modname = mod_map->mod->name;
5956 break;
5957 }
5958 }
5959 preempt_enable();
5960
5961 return ret;
5962}
5963
5964int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *value,
5965 char *type, char *name,
5966 char *module_name, int *exported)
5967{
5968 struct ftrace_mod_map *mod_map;
5969 struct ftrace_mod_func *mod_func;
5970
5971 preempt_disable();
5972 list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) {
5973
5974 if (symnum >= mod_map->num_funcs) {
5975 symnum -= mod_map->num_funcs;
5976 continue;
5977 }
5978
5979 list_for_each_entry_rcu(mod_func, &mod_map->funcs, list) {
5980 if (symnum > 1) {
5981 symnum--;
5982 continue;
5983 }
5984
5985 *value = mod_func->ip;
5986 *type = 'T';
5987 strlcpy(name, mod_func->name, KSYM_NAME_LEN);
5988 strlcpy(module_name, mod_map->mod->name, MODULE_NAME_LEN);
5989 *exported = 1;
5990 preempt_enable();
5991 return 0;
5992 }
5993 WARN_ON(1);
5994 break;
5995 }
5996 preempt_enable();
5997 return -ERANGE;
5998}
5999
6000#else
6001static void save_ftrace_mod_rec(struct ftrace_mod_map *mod_map,
6002 struct dyn_ftrace *rec) { }
6003static inline struct ftrace_mod_map *
6004allocate_ftrace_mod_map(struct module *mod,
6005 unsigned long start, unsigned long end)
6006{
6007 return NULL;
6008}
6009#endif
6010
6011struct ftrace_init_func {
6012 struct list_head list;
6013 unsigned long ip;
6014};
6015
6016
6017static void
6018clear_func_from_hash(struct ftrace_init_func *func, struct ftrace_hash *hash)
6019{
6020 struct ftrace_func_entry *entry;
6021
6022 if (ftrace_hash_empty(hash))
6023 return;
6024
6025 entry = __ftrace_lookup_ip(hash, func->ip);
6026
6027
6028
6029
6030
6031
6032 if (entry)
6033 entry->ip = 0;
6034}
6035
6036static void
6037clear_func_from_hashes(struct ftrace_init_func *func)
6038{
6039 struct trace_array *tr;
6040
6041 mutex_lock(&trace_types_lock);
6042 list_for_each_entry(tr, &ftrace_trace_arrays, list) {
6043 if (!tr->ops || !tr->ops->func_hash)
6044 continue;
6045 mutex_lock(&tr->ops->func_hash->regex_lock);
6046 clear_func_from_hash(func, tr->ops->func_hash->filter_hash);
6047 clear_func_from_hash(func, tr->ops->func_hash->notrace_hash);
6048 mutex_unlock(&tr->ops->func_hash->regex_lock);
6049 }
6050 mutex_unlock(&trace_types_lock);
6051}
6052
6053static void add_to_clear_hash_list(struct list_head *clear_list,
6054 struct dyn_ftrace *rec)
6055{
6056 struct ftrace_init_func *func;
6057
6058 func = kmalloc(sizeof(*func), GFP_KERNEL);
6059 if (!func) {
6060 WARN_ONCE(1, "alloc failure, ftrace filter could be stale\n");
6061 return;
6062 }
6063
6064 func->ip = rec->ip;
6065 list_add(&func->list, clear_list);
6066}
6067
6068void ftrace_free_mem(struct module *mod, void *start_ptr, void *end_ptr)
6069{
6070 unsigned long start = (unsigned long)(start_ptr);
6071 unsigned long end = (unsigned long)(end_ptr);
6072 struct ftrace_page **last_pg = &ftrace_pages_start;
6073 struct ftrace_page *pg;
6074 struct dyn_ftrace *rec;
6075 struct dyn_ftrace key;
6076 struct ftrace_mod_map *mod_map = NULL;
6077 struct ftrace_init_func *func, *func_next;
6078 struct list_head clear_hash;
6079 int order;
6080
6081 INIT_LIST_HEAD(&clear_hash);
6082
6083 key.ip = start;
6084 key.flags = end;
6085
6086 mutex_lock(&ftrace_lock);
6087
6088
6089
6090
6091
6092
6093 if (mod && ftrace_ops_list != &ftrace_list_end)
6094 mod_map = allocate_ftrace_mod_map(mod, start, end);
6095
6096 for (pg = ftrace_pages_start; pg; last_pg = &pg->next, pg = *last_pg) {
6097 if (end < pg->records[0].ip ||
6098 start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE))
6099 continue;
6100 again:
6101 rec = bsearch(&key, pg->records, pg->index,
6102 sizeof(struct dyn_ftrace),
6103 ftrace_cmp_recs);
6104 if (!rec)
6105 continue;
6106
6107
6108 add_to_clear_hash_list(&clear_hash, rec);
6109
6110 if (mod_map)
6111 save_ftrace_mod_rec(mod_map, rec);
6112
6113 pg->index--;
6114 ftrace_update_tot_cnt--;
6115 if (!pg->index) {
6116 *last_pg = pg->next;
6117 order = get_count_order(pg->size / ENTRIES_PER_PAGE);
6118 free_pages((unsigned long)pg->records, order);
6119 kfree(pg);
6120 pg = container_of(last_pg, struct ftrace_page, next);
6121 if (!(*last_pg))
6122 ftrace_pages = pg;
6123 continue;
6124 }
6125 memmove(rec, rec + 1,
6126 (pg->index - (rec - pg->records)) * sizeof(*rec));
6127
6128 goto again;
6129 }
6130 mutex_unlock(&ftrace_lock);
6131
6132 list_for_each_entry_safe(func, func_next, &clear_hash, list) {
6133 clear_func_from_hashes(func);
6134 kfree(func);
6135 }
6136}
6137
6138void __init ftrace_free_init_mem(void)
6139{
6140 void *start = (void *)(&__init_begin);
6141 void *end = (void *)(&__init_end);
6142
6143 ftrace_free_mem(NULL, start, end);
6144}
6145
6146void __init ftrace_init(void)
6147{
6148 extern unsigned long __start_mcount_loc[];
6149 extern unsigned long __stop_mcount_loc[];
6150 unsigned long count, flags;
6151 int ret;
6152
6153 local_irq_save(flags);
6154 ret = ftrace_dyn_arch_init();
6155 local_irq_restore(flags);
6156 if (ret)
6157 goto failed;
6158
6159 count = __stop_mcount_loc - __start_mcount_loc;
6160 if (!count) {
6161 pr_info("ftrace: No functions to be traced?\n");
6162 goto failed;
6163 }
6164
6165 pr_info("ftrace: allocating %ld entries in %ld pages\n",
6166 count, count / ENTRIES_PER_PAGE + 1);
6167
6168 last_ftrace_enabled = ftrace_enabled = 1;
6169
6170 ret = ftrace_process_locs(NULL,
6171 __start_mcount_loc,
6172 __stop_mcount_loc);
6173
6174 set_ftrace_early_filters();
6175
6176 return;
6177 failed:
6178 ftrace_disabled = 1;
6179}
6180
6181
6182void __weak arch_ftrace_update_trampoline(struct ftrace_ops *ops)
6183{
6184}
6185
6186static void ftrace_update_trampoline(struct ftrace_ops *ops)
6187{
6188 arch_ftrace_update_trampoline(ops);
6189}
6190
6191void ftrace_init_trace_array(struct trace_array *tr)
6192{
6193 INIT_LIST_HEAD(&tr->func_probes);
6194 INIT_LIST_HEAD(&tr->mod_trace);
6195 INIT_LIST_HEAD(&tr->mod_notrace);
6196}
6197#else
6198
6199struct ftrace_ops global_ops = {
6200 .func = ftrace_stub,
6201 .flags = FTRACE_OPS_FL_RECURSION_SAFE |
6202 FTRACE_OPS_FL_INITIALIZED |
6203 FTRACE_OPS_FL_PID,
6204};
6205
6206static int __init ftrace_nodyn_init(void)
6207{
6208 ftrace_enabled = 1;
6209 return 0;
6210}
6211core_initcall(ftrace_nodyn_init);
6212
6213static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; }
6214static inline void ftrace_startup_enable(int command) { }
6215static inline void ftrace_startup_all(int command) { }
6216
6217# define ftrace_startup_sysctl() do { } while (0)
6218# define ftrace_shutdown_sysctl() do { } while (0)
6219
6220static void ftrace_update_trampoline(struct ftrace_ops *ops)
6221{
6222}
6223
6224#endif
6225
6226__init void ftrace_init_global_array_ops(struct trace_array *tr)
6227{
6228 tr->ops = &global_ops;
6229 tr->ops->private = tr;
6230 ftrace_init_trace_array(tr);
6231}
6232
6233void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func)
6234{
6235
6236 if (tr->flags & TRACE_ARRAY_FL_GLOBAL) {
6237 if (WARN_ON(tr->ops->func != ftrace_stub))
6238 printk("ftrace ops had %pS for function\n",
6239 tr->ops->func);
6240 }
6241 tr->ops->func = func;
6242 tr->ops->private = tr;
6243}
6244
6245void ftrace_reset_array_ops(struct trace_array *tr)
6246{
6247 tr->ops->func = ftrace_stub;
6248}
6249
6250static nokprobe_inline void
6251__ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
6252 struct ftrace_ops *ignored, struct pt_regs *regs)
6253{
6254 struct ftrace_ops *op;
6255 int bit;
6256
6257 bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX);
6258 if (bit < 0)
6259 return;
6260
6261
6262
6263
6264
6265 preempt_disable_notrace();
6266
6267 do_for_each_ftrace_op(op, ftrace_ops_list) {
6268
6269
6270
6271
6272
6273
6274
6275
6276
6277 if ((!(op->flags & FTRACE_OPS_FL_RCU) || rcu_is_watching()) &&
6278 ftrace_ops_test(op, ip, regs)) {
6279 if (FTRACE_WARN_ON(!op->func)) {
6280 pr_warn("op=%p %pS\n", op, op);
6281 goto out;
6282 }
6283 op->func(ip, parent_ip, op, regs);
6284 }
6285 } while_for_each_ftrace_op(op);
6286out:
6287 preempt_enable_notrace();
6288 trace_clear_recursion(bit);
6289}
6290
6291
6292
6293
6294
6295
6296
6297
6298
6299
6300
6301
6302
6303
6304#if ARCH_SUPPORTS_FTRACE_OPS
6305static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
6306 struct ftrace_ops *op, struct pt_regs *regs)
6307{
6308 __ftrace_ops_list_func(ip, parent_ip, NULL, regs);
6309}
6310NOKPROBE_SYMBOL(ftrace_ops_list_func);
6311#else
6312static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip)
6313{
6314 __ftrace_ops_list_func(ip, parent_ip, NULL, NULL);
6315}
6316NOKPROBE_SYMBOL(ftrace_ops_no_ops);
6317#endif
6318
6319
6320
6321
6322
6323
6324static void ftrace_ops_assist_func(unsigned long ip, unsigned long parent_ip,
6325 struct ftrace_ops *op, struct pt_regs *regs)
6326{
6327 int bit;
6328
6329 if ((op->flags & FTRACE_OPS_FL_RCU) && !rcu_is_watching())
6330 return;
6331
6332 bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX);
6333 if (bit < 0)
6334 return;
6335
6336 preempt_disable_notrace();
6337
6338 op->func(ip, parent_ip, op, regs);
6339
6340 preempt_enable_notrace();
6341 trace_clear_recursion(bit);
6342}
6343NOKPROBE_SYMBOL(ftrace_ops_assist_func);
6344
6345
6346
6347
6348
6349
6350
6351
6352
6353
6354
6355
6356ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops)
6357{
6358
6359
6360
6361
6362 if (!(ops->flags & FTRACE_OPS_FL_RECURSION_SAFE) ||
6363 ops->flags & FTRACE_OPS_FL_RCU)
6364 return ftrace_ops_assist_func;
6365
6366 return ops->func;
6367}
6368
6369static void
6370ftrace_filter_pid_sched_switch_probe(void *data, bool preempt,
6371 struct task_struct *prev, struct task_struct *next)
6372{
6373 struct trace_array *tr = data;
6374 struct trace_pid_list *pid_list;
6375
6376 pid_list = rcu_dereference_sched(tr->function_pids);
6377
6378 this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid,
6379 trace_ignore_this_task(pid_list, next));
6380}
6381
6382static void
6383ftrace_pid_follow_sched_process_fork(void *data,
6384 struct task_struct *self,
6385 struct task_struct *task)
6386{
6387 struct trace_pid_list *pid_list;
6388 struct trace_array *tr = data;
6389
6390 pid_list = rcu_dereference_sched(tr->function_pids);
6391 trace_filter_add_remove_task(pid_list, self, task);
6392}
6393
6394static void
6395ftrace_pid_follow_sched_process_exit(void *data, struct task_struct *task)
6396{
6397 struct trace_pid_list *pid_list;
6398 struct trace_array *tr = data;
6399
6400 pid_list = rcu_dereference_sched(tr->function_pids);
6401 trace_filter_add_remove_task(pid_list, NULL, task);
6402}
6403
6404void ftrace_pid_follow_fork(struct trace_array *tr, bool enable)
6405{
6406 if (enable) {
6407 register_trace_sched_process_fork(ftrace_pid_follow_sched_process_fork,
6408 tr);
6409 register_trace_sched_process_exit(ftrace_pid_follow_sched_process_exit,
6410 tr);
6411 } else {
6412 unregister_trace_sched_process_fork(ftrace_pid_follow_sched_process_fork,
6413 tr);
6414 unregister_trace_sched_process_exit(ftrace_pid_follow_sched_process_exit,
6415 tr);
6416 }
6417}
6418
6419static void clear_ftrace_pids(struct trace_array *tr)
6420{
6421 struct trace_pid_list *pid_list;
6422 int cpu;
6423
6424 pid_list = rcu_dereference_protected(tr->function_pids,
6425 lockdep_is_held(&ftrace_lock));
6426 if (!pid_list)
6427 return;
6428
6429 unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr);
6430
6431 for_each_possible_cpu(cpu)
6432 per_cpu_ptr(tr->trace_buffer.data, cpu)->ftrace_ignore_pid = false;
6433
6434 rcu_assign_pointer(tr->function_pids, NULL);
6435
6436
6437 synchronize_rcu();
6438
6439 trace_free_pid_list(pid_list);
6440}
6441
6442void ftrace_clear_pids(struct trace_array *tr)
6443{
6444 mutex_lock(&ftrace_lock);
6445
6446 clear_ftrace_pids(tr);
6447
6448 mutex_unlock(&ftrace_lock);
6449}
6450
6451static void ftrace_pid_reset(struct trace_array *tr)
6452{
6453 mutex_lock(&ftrace_lock);
6454 clear_ftrace_pids(tr);
6455
6456 ftrace_update_pid_func();
6457 ftrace_startup_all(0);
6458
6459 mutex_unlock(&ftrace_lock);
6460}
6461
6462
6463#define FTRACE_NO_PIDS (void *)(PID_MAX_LIMIT + 1)
6464
6465static void *fpid_start(struct seq_file *m, loff_t *pos)
6466 __acquires(RCU)
6467{
6468 struct trace_pid_list *pid_list;
6469 struct trace_array *tr = m->private;
6470
6471 mutex_lock(&ftrace_lock);
6472 rcu_read_lock_sched();
6473
6474 pid_list = rcu_dereference_sched(tr->function_pids);
6475
6476 if (!pid_list)
6477 return !(*pos) ? FTRACE_NO_PIDS : NULL;
6478
6479 return trace_pid_start(pid_list, pos);
6480}
6481
6482static void *fpid_next(struct seq_file *m, void *v, loff_t *pos)
6483{
6484 struct trace_array *tr = m->private;
6485 struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_pids);
6486
6487 if (v == FTRACE_NO_PIDS)
6488 return NULL;
6489
6490 return trace_pid_next(pid_list, v, pos);
6491}
6492
6493static void fpid_stop(struct seq_file *m, void *p)
6494 __releases(RCU)
6495{
6496 rcu_read_unlock_sched();
6497 mutex_unlock(&ftrace_lock);
6498}
6499
6500static int fpid_show(struct seq_file *m, void *v)
6501{
6502 if (v == FTRACE_NO_PIDS) {
6503 seq_puts(m, "no pid\n");
6504 return 0;
6505 }
6506
6507 return trace_pid_show(m, v);
6508}
6509
6510static const struct seq_operations ftrace_pid_sops = {
6511 .start = fpid_start,
6512 .next = fpid_next,
6513 .stop = fpid_stop,
6514 .show = fpid_show,
6515};
6516
6517static int
6518ftrace_pid_open(struct inode *inode, struct file *file)
6519{
6520 struct trace_array *tr = inode->i_private;
6521 struct seq_file *m;
6522 int ret = 0;
6523
6524 if (trace_array_get(tr) < 0)
6525 return -ENODEV;
6526
6527 if ((file->f_mode & FMODE_WRITE) &&
6528 (file->f_flags & O_TRUNC))
6529 ftrace_pid_reset(tr);
6530
6531 ret = seq_open(file, &ftrace_pid_sops);
6532 if (ret < 0) {
6533 trace_array_put(tr);
6534 } else {
6535 m = file->private_data;
6536
6537 m->private = tr;
6538 }
6539
6540 return ret;
6541}
6542
6543static void ignore_task_cpu(void *data)
6544{
6545 struct trace_array *tr = data;
6546 struct trace_pid_list *pid_list;
6547
6548
6549
6550
6551
6552 pid_list = rcu_dereference_protected(tr->function_pids,
6553 mutex_is_locked(&ftrace_lock));
6554
6555 this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid,
6556 trace_ignore_this_task(pid_list, current));
6557}
6558
6559static ssize_t
6560ftrace_pid_write(struct file *filp, const char __user *ubuf,
6561 size_t cnt, loff_t *ppos)
6562{
6563 struct seq_file *m = filp->private_data;
6564 struct trace_array *tr = m->private;
6565 struct trace_pid_list *filtered_pids = NULL;
6566 struct trace_pid_list *pid_list;
6567 ssize_t ret;
6568
6569 if (!cnt)
6570 return 0;
6571
6572 mutex_lock(&ftrace_lock);
6573
6574 filtered_pids = rcu_dereference_protected(tr->function_pids,
6575 lockdep_is_held(&ftrace_lock));
6576
6577 ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt);
6578 if (ret < 0)
6579 goto out;
6580
6581 rcu_assign_pointer(tr->function_pids, pid_list);
6582
6583 if (filtered_pids) {
6584 synchronize_rcu();
6585 trace_free_pid_list(filtered_pids);
6586 } else if (pid_list) {
6587
6588 register_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr);
6589 }
6590
6591
6592
6593
6594
6595
6596 on_each_cpu(ignore_task_cpu, tr, 1);
6597
6598 ftrace_update_pid_func();
6599 ftrace_startup_all(0);
6600 out:
6601 mutex_unlock(&ftrace_lock);
6602
6603 if (ret > 0)
6604 *ppos += ret;
6605
6606 return ret;
6607}
6608
6609static int
6610ftrace_pid_release(struct inode *inode, struct file *file)
6611{
6612 struct trace_array *tr = inode->i_private;
6613
6614 trace_array_put(tr);
6615
6616 return seq_release(inode, file);
6617}
6618
6619static const struct file_operations ftrace_pid_fops = {
6620 .open = ftrace_pid_open,
6621 .write = ftrace_pid_write,
6622 .read = seq_read,
6623 .llseek = tracing_lseek,
6624 .release = ftrace_pid_release,
6625};
6626
6627void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer)
6628{
6629 trace_create_file("set_ftrace_pid", 0644, d_tracer,
6630 tr, &ftrace_pid_fops);
6631}
6632
6633void __init ftrace_init_tracefs_toplevel(struct trace_array *tr,
6634 struct dentry *d_tracer)
6635{
6636
6637 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
6638
6639 ftrace_init_dyn_tracefs(d_tracer);
6640 ftrace_profile_tracefs(d_tracer);
6641}
6642
6643
6644
6645
6646
6647
6648
6649
6650void ftrace_kill(void)
6651{
6652 ftrace_disabled = 1;
6653 ftrace_enabled = 0;
6654 ftrace_trace_function = ftrace_stub;
6655}
6656
6657
6658
6659
6660int ftrace_is_dead(void)
6661{
6662 return ftrace_disabled;
6663}
6664
6665
6666
6667
6668
6669
6670
6671
6672
6673
6674
6675
6676int register_ftrace_function(struct ftrace_ops *ops)
6677{
6678 int ret = -1;
6679
6680 ftrace_ops_init(ops);
6681
6682 mutex_lock(&ftrace_lock);
6683
6684 ret = ftrace_startup(ops, 0);
6685
6686 mutex_unlock(&ftrace_lock);
6687
6688 return ret;
6689}
6690EXPORT_SYMBOL_GPL(register_ftrace_function);
6691
6692
6693
6694
6695
6696
6697
6698int unregister_ftrace_function(struct ftrace_ops *ops)
6699{
6700 int ret;
6701
6702 mutex_lock(&ftrace_lock);
6703 ret = ftrace_shutdown(ops, 0);
6704 mutex_unlock(&ftrace_lock);
6705
6706 return ret;
6707}
6708EXPORT_SYMBOL_GPL(unregister_ftrace_function);
6709
6710int
6711ftrace_enable_sysctl(struct ctl_table *table, int write,
6712 void __user *buffer, size_t *lenp,
6713 loff_t *ppos)
6714{
6715 int ret = -ENODEV;
6716
6717 mutex_lock(&ftrace_lock);
6718
6719 if (unlikely(ftrace_disabled))
6720 goto out;
6721
6722 ret = proc_dointvec(table, write, buffer, lenp, ppos);
6723
6724 if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
6725 goto out;
6726
6727 last_ftrace_enabled = !!ftrace_enabled;
6728
6729 if (ftrace_enabled) {
6730
6731
6732 if (rcu_dereference_protected(ftrace_ops_list,
6733 lockdep_is_held(&ftrace_lock)) != &ftrace_list_end)
6734 update_ftrace_function();
6735
6736 ftrace_startup_sysctl();
6737
6738 } else {
6739
6740 ftrace_trace_function = ftrace_stub;
6741
6742 ftrace_shutdown_sysctl();
6743 }
6744
6745 out:
6746 mutex_unlock(&ftrace_lock);
6747 return ret;
6748}
6749