1 // SPDX-License-Identifier: GPL-2.0
2
3 #ifndef _LINUX_KERNEL_TRACE_H
4 #define _LINUX_KERNEL_TRACE_H
5
6 #include <linux/fs.h>
7 #include <linux/atomic.h>
8 #include <linux/sched.h>
9 #include <linux/clocksource.h>
10 #include <linux/ring_buffer.h>
11 #include <linux/mmiotrace.h>
12 #include <linux/tracepoint.h>
13 #include <linux/ftrace.h>
14 #include <linux/trace.h>
15 #include <linux/hw_breakpoint.h>
16 #include <linux/trace_seq.h>
17 #include <linux/trace_events.h>
18 #include <linux/compiler.h>
19 #include <linux/glob.h>
20 #include <linux/irq_work.h>
21 #include <linux/workqueue.h>
22 #include <linux/ctype.h>
23 #include <linux/once_lite.h>
24
25 #include "pid_list.h"
26
27 #ifdef CONFIG_FTRACE_SYSCALLS
28 #include <asm/unistd.h> /* For NR_syscalls */
29 #include <asm/syscall.h> /* some archs define it here */
30 #endif
31
32 #define TRACE_MODE_WRITE 0640
33 #define TRACE_MODE_READ 0440
34
35 enum trace_type {
36 __TRACE_FIRST_TYPE = 0,
37
38 TRACE_FN,
39 TRACE_CTX,
40 TRACE_WAKE,
41 TRACE_STACK,
42 TRACE_PRINT,
43 TRACE_BPRINT,
44 TRACE_MMIO_RW,
45 TRACE_MMIO_MAP,
46 TRACE_BRANCH,
47 TRACE_GRAPH_RET,
48 TRACE_GRAPH_ENT,
49 TRACE_USER_STACK,
50 TRACE_BLK,
51 TRACE_BPUTS,
52 TRACE_HWLAT,
53 TRACE_OSNOISE,
54 TRACE_TIMERLAT,
55 TRACE_RAW_DATA,
56 TRACE_FUNC_REPEATS,
57
58 __TRACE_LAST_TYPE,
59 };
60
61
62 #undef __field
63 #define __field(type, item) type item;
64
65 #undef __field_fn
66 #define __field_fn(type, item) type item;
67
68 #undef __field_struct
69 #define __field_struct(type, item) __field(type, item)
70
71 #undef __field_desc
72 #define __field_desc(type, container, item)
73
74 #undef __field_packed
75 #define __field_packed(type, container, item)
76
77 #undef __array
78 #define __array(type, item, size) type item[size];
79
80 /*
81 * For backward compatibility, older user space expects to see the
82 * kernel_stack event with a fixed size caller field. But today the fix
83 * size is ignored by the kernel, and the real structure is dynamic.
84 * Expose to user space: "unsigned long caller[8];" but the real structure
85 * will be "unsigned long caller[] __counted_by(size)"
86 */
87 #undef __stack_array
88 #define __stack_array(type, item, size, field) type item[] __counted_by(field);
89
90 #undef __array_desc
91 #define __array_desc(type, container, item, size)
92
93 #undef __dynamic_array
94 #define __dynamic_array(type, item) type item[];
95
96 #undef __rel_dynamic_array
97 #define __rel_dynamic_array(type, item) type item[];
98
99 #undef F_STRUCT
100 #define F_STRUCT(args...) args
101
102 #undef FTRACE_ENTRY
103 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
104 struct struct_name { \
105 struct trace_entry ent; \
106 tstruct \
107 }
108
109 #undef FTRACE_ENTRY_DUP
110 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
111
112 #undef FTRACE_ENTRY_REG
113 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, regfn) \
114 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
115
116 #undef FTRACE_ENTRY_PACKED
117 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print) \
118 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
119
120 #include "trace_entries.h"
121
122 /* Use this for memory failure errors */
123 #define MEM_FAIL(condition, fmt, ...) \
124 DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
125
126 #define FAULT_STRING "(fault)"
127
128 #define HIST_STACKTRACE_DEPTH 16
129 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
130 #define HIST_STACKTRACE_SKIP 5
131
132 /*
133 * syscalls are special, and need special handling, this is why
134 * they are not included in trace_entries.h
135 */
136 struct syscall_trace_enter {
137 struct trace_entry ent;
138 int nr;
139 unsigned long args[];
140 };
141
142 struct syscall_trace_exit {
143 struct trace_entry ent;
144 int nr;
145 long ret;
146 };
147
148 struct kprobe_trace_entry_head {
149 struct trace_entry ent;
150 unsigned long ip;
151 };
152
153 struct eprobe_trace_entry_head {
154 struct trace_entry ent;
155 };
156
157 struct kretprobe_trace_entry_head {
158 struct trace_entry ent;
159 unsigned long func;
160 unsigned long ret_ip;
161 };
162
163 struct fentry_trace_entry_head {
164 struct trace_entry ent;
165 unsigned long ip;
166 };
167
168 struct fexit_trace_entry_head {
169 struct trace_entry ent;
170 unsigned long func;
171 unsigned long ret_ip;
172 };
173
174 #define TRACE_BUF_SIZE 1024
175
176 struct trace_array;
177
178 /*
179 * The CPU trace array - it consists of thousands of trace entries
180 * plus some other descriptor data: (for example which task started
181 * the trace, etc.)
182 */
183 struct trace_array_cpu {
184 atomic_t disabled;
185 void *buffer_page; /* ring buffer spare */
186
187 unsigned long entries;
188 unsigned long saved_latency;
189 unsigned long critical_start;
190 unsigned long critical_end;
191 unsigned long critical_sequence;
192 unsigned long nice;
193 unsigned long policy;
194 unsigned long rt_priority;
195 unsigned long skipped_entries;
196 u64 preempt_timestamp;
197 pid_t pid;
198 kuid_t uid;
199 char comm[TASK_COMM_LEN];
200
201 #ifdef CONFIG_FUNCTION_TRACER
202 int ftrace_ignore_pid;
203 #endif
204 bool ignore_pid;
205 };
206
207 struct tracer;
208 struct trace_option_dentry;
209
210 struct array_buffer {
211 struct trace_array *tr;
212 struct trace_buffer *buffer;
213 struct trace_array_cpu __percpu *data;
214 u64 time_start;
215 int cpu;
216 };
217
218 #define TRACE_FLAGS_MAX_SIZE 32
219
220 struct trace_options {
221 struct tracer *tracer;
222 struct trace_option_dentry *topts;
223 };
224
225 struct trace_pid_list *trace_pid_list_alloc(void);
226 void trace_pid_list_free(struct trace_pid_list *pid_list);
227 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
228 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
229 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
230 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
231 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
232 unsigned int *next);
233
234 enum {
235 TRACE_PIDS = BIT(0),
236 TRACE_NO_PIDS = BIT(1),
237 };
238
239 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
240 struct trace_pid_list *no_pid_list)
241 {
242 /* Return true if the pid list in type has pids */
243 return ((type & TRACE_PIDS) && pid_list) ||
244 ((type & TRACE_NO_PIDS) && no_pid_list);
245 }
246
247 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
248 struct trace_pid_list *no_pid_list)
249 {
250 /*
251 * Turning off what is in @type, return true if the "other"
252 * pid list, still has pids in it.
253 */
254 return (!(type & TRACE_PIDS) && pid_list) ||
255 (!(type & TRACE_NO_PIDS) && no_pid_list);
256 }
257
258 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
259
260 /**
261 * struct cond_snapshot - conditional snapshot data and callback
262 *
263 * The cond_snapshot structure encapsulates a callback function and
264 * data associated with the snapshot for a given tracing instance.
265 *
266 * When a snapshot is taken conditionally, by invoking
267 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
268 * passed in turn to the cond_snapshot.update() function. That data
269 * can be compared by the update() implementation with the cond_data
270 * contained within the struct cond_snapshot instance associated with
271 * the trace_array. Because the tr->max_lock is held throughout the
272 * update() call, the update() function can directly retrieve the
273 * cond_snapshot and cond_data associated with the per-instance
274 * snapshot associated with the trace_array.
275 *
276 * The cond_snapshot.update() implementation can save data to be
277 * associated with the snapshot if it decides to, and returns 'true'
278 * in that case, or it returns 'false' if the conditional snapshot
279 * shouldn't be taken.
280 *
281 * The cond_snapshot instance is created and associated with the
282 * user-defined cond_data by tracing_cond_snapshot_enable().
283 * Likewise, the cond_snapshot instance is destroyed and is no longer
284 * associated with the trace instance by
285 * tracing_cond_snapshot_disable().
286 *
287 * The method below is required.
288 *
289 * @update: When a conditional snapshot is invoked, the update()
290 * callback function is invoked with the tr->max_lock held. The
291 * update() implementation signals whether or not to actually
292 * take the snapshot, by returning 'true' if so, 'false' if no
293 * snapshot should be taken. Because the max_lock is held for
294 * the duration of update(), the implementation is safe to
295 * directly retrieved and save any implementation data it needs
296 * to in association with the snapshot.
297 */
298 struct cond_snapshot {
299 void *cond_data;
300 cond_update_fn_t update;
301 };
302
303 /*
304 * struct trace_func_repeats - used to keep track of the consecutive
305 * (on the same CPU) calls of a single function.
306 */
307 struct trace_func_repeats {
308 unsigned long ip;
309 unsigned long parent_ip;
310 unsigned long count;
311 u64 ts_last_call;
312 };
313
314 /*
315 * The trace array - an array of per-CPU trace arrays. This is the
316 * highest level data structure that individual tracers deal with.
317 * They have on/off state as well:
318 */
319 struct trace_array {
320 struct list_head list;
321 char *name;
322 struct array_buffer array_buffer;
323 #ifdef CONFIG_TRACER_MAX_TRACE
324 /*
325 * The max_buffer is used to snapshot the trace when a maximum
326 * latency is reached, or when the user initiates a snapshot.
327 * Some tracers will use this to store a maximum trace while
328 * it continues examining live traces.
329 *
330 * The buffers for the max_buffer are set up the same as the array_buffer
331 * When a snapshot is taken, the buffer of the max_buffer is swapped
332 * with the buffer of the array_buffer and the buffers are reset for
333 * the array_buffer so the tracing can continue.
334 */
335 struct array_buffer max_buffer;
336 bool allocated_snapshot;
337 spinlock_t snapshot_trigger_lock;
338 unsigned int snapshot;
339 unsigned int mapped;
340 unsigned long max_latency;
341 #ifdef CONFIG_FSNOTIFY
342 struct dentry *d_max_latency;
343 struct work_struct fsnotify_work;
344 struct irq_work fsnotify_irqwork;
345 #endif
346 #endif
347 struct trace_pid_list __rcu *filtered_pids;
348 struct trace_pid_list __rcu *filtered_no_pids;
349 /*
350 * max_lock is used to protect the swapping of buffers
351 * when taking a max snapshot. The buffers themselves are
352 * protected by per_cpu spinlocks. But the action of the swap
353 * needs its own lock.
354 *
355 * This is defined as a arch_spinlock_t in order to help
356 * with performance when lockdep debugging is enabled.
357 *
358 * It is also used in other places outside the update_max_tr
359 * so it needs to be defined outside of the
360 * CONFIG_TRACER_MAX_TRACE.
361 */
362 arch_spinlock_t max_lock;
363 int buffer_disabled;
364 #ifdef CONFIG_FTRACE_SYSCALLS
365 int sys_refcount_enter;
366 int sys_refcount_exit;
367 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
368 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
369 #endif
370 int stop_count;
371 int clock_id;
372 int nr_topts;
373 bool clear_trace;
374 int buffer_percent;
375 unsigned int n_err_log_entries;
376 struct tracer *current_trace;
377 unsigned int trace_flags;
378 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
379 unsigned int flags;
380 raw_spinlock_t start_lock;
381 const char *system_names;
382 struct list_head err_log;
383 struct dentry *dir;
384 struct dentry *options;
385 struct dentry *percpu_dir;
386 struct eventfs_inode *event_dir;
387 struct trace_options *topts;
388 struct list_head systems;
389 struct list_head events;
390 struct trace_event_file *trace_marker_file;
391 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
392 /* one per_cpu trace_pipe can be opened by only one user */
393 cpumask_var_t pipe_cpumask;
394 int ref;
395 int trace_ref;
396 #ifdef CONFIG_FUNCTION_TRACER
397 struct ftrace_ops *ops;
398 struct trace_pid_list __rcu *function_pids;
399 struct trace_pid_list __rcu *function_no_pids;
400 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
401 struct fgraph_ops *gops;
402 #endif
403 #ifdef CONFIG_DYNAMIC_FTRACE
404 /* All of these are protected by the ftrace_lock */
405 struct list_head func_probes;
406 struct list_head mod_trace;
407 struct list_head mod_notrace;
408 #endif
409 /* function tracing enabled */
410 int function_enabled;
411 #endif
412 int no_filter_buffering_ref;
413 struct list_head hist_vars;
414 #ifdef CONFIG_TRACER_SNAPSHOT
415 struct cond_snapshot *cond_snapshot;
416 #endif
417 struct trace_func_repeats __percpu *last_func_repeats;
418 /*
419 * On boot up, the ring buffer is set to the minimum size, so that
420 * we do not waste memory on systems that are not using tracing.
421 */
422 bool ring_buffer_expanded;
423 };
424
425 enum {
426 TRACE_ARRAY_FL_GLOBAL = (1 << 0)
427 };
428
429 extern struct list_head ftrace_trace_arrays;
430
431 extern struct mutex trace_types_lock;
432
433 extern int trace_array_get(struct trace_array *tr);
434 extern int tracing_check_open_get_tr(struct trace_array *tr);
435 extern struct trace_array *trace_array_find(const char *instance);
436 extern struct trace_array *trace_array_find_get(const char *instance);
437
438 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
439 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
440 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
441
442 extern bool trace_clock_in_ns(struct trace_array *tr);
443
444 /*
445 * The global tracer (top) should be the first trace array added,
446 * but we check the flag anyway.
447 */
448 static inline struct trace_array *top_trace_array(void)
449 {
450 struct trace_array *tr;
451
452 if (list_empty(&ftrace_trace_arrays))
453 return NULL;
454
455 tr = list_entry(ftrace_trace_arrays.prev,
456 typeof(*tr), list);
457 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
458 return tr;
459 }
460
461 #define FTRACE_CMP_TYPE(var, type) \
462 __builtin_types_compatible_p(typeof(var), type *)
463
464 #undef IF_ASSIGN
465 #define IF_ASSIGN(var, entry, etype, id) \
466 if (FTRACE_CMP_TYPE(var, etype)) { \
467 var = (typeof(var))(entry); \
468 WARN_ON(id != 0 && (entry)->type != id); \
469 break; \
470 }
471
472 /* Will cause compile errors if type is not found. */
473 extern void __ftrace_bad_type(void);
474
475 /*
476 * The trace_assign_type is a verifier that the entry type is
477 * the same as the type being assigned. To add new types simply
478 * add a line with the following format:
479 *
480 * IF_ASSIGN(var, ent, type, id);
481 *
482 * Where "type" is the trace type that includes the trace_entry
483 * as the "ent" item. And "id" is the trace identifier that is
484 * used in the trace_type enum.
485 *
486 * If the type can have more than one id, then use zero.
487 */
488 #define trace_assign_type(var, ent) \
489 do { \
490 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
491 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
492 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
493 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
494 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
495 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
496 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
497 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
498 IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
499 IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
500 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
501 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
502 TRACE_MMIO_RW); \
503 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
504 TRACE_MMIO_MAP); \
505 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
506 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
507 TRACE_GRAPH_ENT); \
508 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
509 TRACE_GRAPH_RET); \
510 IF_ASSIGN(var, ent, struct func_repeats_entry, \
511 TRACE_FUNC_REPEATS); \
512 __ftrace_bad_type(); \
513 } while (0)
514
515 /*
516 * An option specific to a tracer. This is a boolean value.
517 * The bit is the bit index that sets its value on the
518 * flags value in struct tracer_flags.
519 */
520 struct tracer_opt {
521 const char *name; /* Will appear on the trace_options file */
522 u32 bit; /* Mask assigned in val field in tracer_flags */
523 };
524
525 /*
526 * The set of specific options for a tracer. Your tracer
527 * have to set the initial value of the flags val.
528 */
529 struct tracer_flags {
530 u32 val;
531 struct tracer_opt *opts;
532 struct tracer *trace;
533 };
534
535 /* Makes more easy to define a tracer opt */
536 #define TRACER_OPT(s, b) .name = #s, .bit = b
537
538
539 struct trace_option_dentry {
540 struct tracer_opt *opt;
541 struct tracer_flags *flags;
542 struct trace_array *tr;
543 struct dentry *entry;
544 };
545
546 /**
547 * struct tracer - a specific tracer and its callbacks to interact with tracefs
548 * @name: the name chosen to select it on the available_tracers file
549 * @init: called when one switches to this tracer (echo name > current_tracer)
550 * @reset: called when one switches to another tracer
551 * @start: called when tracing is unpaused (echo 1 > tracing_on)
552 * @stop: called when tracing is paused (echo 0 > tracing_on)
553 * @update_thresh: called when tracing_thresh is updated
554 * @open: called when the trace file is opened
555 * @pipe_open: called when the trace_pipe file is opened
556 * @close: called when the trace file is released
557 * @pipe_close: called when the trace_pipe file is released
558 * @read: override the default read callback on trace_pipe
559 * @splice_read: override the default splice_read callback on trace_pipe
560 * @selftest: selftest to run on boot (see trace_selftest.c)
561 * @print_headers: override the first lines that describe your columns
562 * @print_line: callback that prints a trace
563 * @set_flag: signals one of your private flags changed (trace_options file)
564 * @flags: your private flags
565 */
566 struct tracer {
567 const char *name;
568 int (*init)(struct trace_array *tr);
569 void (*reset)(struct trace_array *tr);
570 void (*start)(struct trace_array *tr);
571 void (*stop)(struct trace_array *tr);
572 int (*update_thresh)(struct trace_array *tr);
573 void (*open)(struct trace_iterator *iter);
574 void (*pipe_open)(struct trace_iterator *iter);
575 void (*close)(struct trace_iterator *iter);
576 void (*pipe_close)(struct trace_iterator *iter);
577 ssize_t (*read)(struct trace_iterator *iter,
578 struct file *filp, char __user *ubuf,
579 size_t cnt, loff_t *ppos);
580 ssize_t (*splice_read)(struct trace_iterator *iter,
581 struct file *filp,
582 loff_t *ppos,
583 struct pipe_inode_info *pipe,
584 size_t len,
585 unsigned int flags);
586 #ifdef CONFIG_FTRACE_STARTUP_TEST
587 int (*selftest)(struct tracer *trace,
588 struct trace_array *tr);
589 #endif
590 void (*print_header)(struct seq_file *m);
591 enum print_line_t (*print_line)(struct trace_iterator *iter);
592 /* If you handled the flag setting, return 0 */
593 int (*set_flag)(struct trace_array *tr,
594 u32 old_flags, u32 bit, int set);
595 /* Return 0 if OK with change, else return non-zero */
596 int (*flag_changed)(struct trace_array *tr,
597 u32 mask, int set);
598 struct tracer *next;
599 struct tracer_flags *flags;
600 int enabled;
601 bool print_max;
602 bool allow_instances;
603 #ifdef CONFIG_TRACER_MAX_TRACE
604 bool use_max_tr;
605 #endif
606 /* True if tracer cannot be enabled in kernel param */
607 bool noboot;
608 };
609
610 static inline struct ring_buffer_iter *
611 trace_buffer_iter(struct trace_iterator *iter, int cpu)
612 {
613 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
614 }
615
616 int tracer_init(struct tracer *t, struct trace_array *tr);
617 int tracing_is_enabled(void);
618 void tracing_reset_online_cpus(struct array_buffer *buf);
619 void tracing_reset_all_online_cpus(void);
620 void tracing_reset_all_online_cpus_unlocked(void);
621 int tracing_open_generic(struct inode *inode, struct file *filp);
622 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
623 int tracing_release_generic_tr(struct inode *inode, struct file *file);
624 int tracing_open_file_tr(struct inode *inode, struct file *filp);
625 int tracing_release_file_tr(struct inode *inode, struct file *filp);
626 int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
627 bool tracing_is_disabled(void);
628 bool tracer_tracing_is_on(struct trace_array *tr);
629 void tracer_tracing_on(struct trace_array *tr);
630 void tracer_tracing_off(struct trace_array *tr);
631 struct dentry *trace_create_file(const char *name,
632 umode_t mode,
633 struct dentry *parent,
634 void *data,
635 const struct file_operations *fops);
636
637 int tracing_init_dentry(void);
638
639 struct ring_buffer_event;
640
641 struct ring_buffer_event *
642 trace_buffer_lock_reserve(struct trace_buffer *buffer,
643 int type,
644 unsigned long len,
645 unsigned int trace_ctx);
646
647 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
648 struct trace_array_cpu *data);
649
650 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
651 int *ent_cpu, u64 *ent_ts);
652
653 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
654 struct ring_buffer_event *event);
655
656 bool trace_is_tracepoint_string(const char *str);
657 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
658 void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
659 va_list ap) __printf(2, 0);
660 char *trace_iter_expand_format(struct trace_iterator *iter);
661
662 int trace_empty(struct trace_iterator *iter);
663
664 void *trace_find_next_entry_inc(struct trace_iterator *iter);
665
666 void trace_init_global_iter(struct trace_iterator *iter);
667
668 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
669
670 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
671 unsigned long trace_total_entries(struct trace_array *tr);
672
673 void trace_function(struct trace_array *tr,
674 unsigned long ip,
675 unsigned long parent_ip,
676 unsigned int trace_ctx);
677 void trace_graph_function(struct trace_array *tr,
678 unsigned long ip,
679 unsigned long parent_ip,
680 unsigned int trace_ctx);
681 void trace_latency_header(struct seq_file *m);
682 void trace_default_header(struct seq_file *m);
683 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
684
685 void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops);
686 int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops);
687
688 void tracing_start_cmdline_record(void);
689 void tracing_stop_cmdline_record(void);
690 void tracing_start_tgid_record(void);
691 void tracing_stop_tgid_record(void);
692
693 int register_tracer(struct tracer *type);
694 int is_tracing_stopped(void);
695
696 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
697
698 extern cpumask_var_t __read_mostly tracing_buffer_mask;
699
700 #define for_each_tracing_cpu(cpu) \
701 for_each_cpu(cpu, tracing_buffer_mask)
702
703 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
704
705 extern unsigned long tracing_thresh;
706
707 /* PID filtering */
708
709 extern int pid_max;
710
711 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
712 pid_t search_pid);
713 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
714 struct trace_pid_list *filtered_no_pids,
715 struct task_struct *task);
716 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
717 struct task_struct *self,
718 struct task_struct *task);
719 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
720 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
721 int trace_pid_show(struct seq_file *m, void *v);
722 int trace_pid_write(struct trace_pid_list *filtered_pids,
723 struct trace_pid_list **new_pid_list,
724 const char __user *ubuf, size_t cnt);
725
726 #ifdef CONFIG_TRACER_MAX_TRACE
727 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
728 void *cond_data);
729 void update_max_tr_single(struct trace_array *tr,
730 struct task_struct *tsk, int cpu);
731
732 #ifdef CONFIG_FSNOTIFY
733 #define LATENCY_FS_NOTIFY
734 #endif
735 #endif /* CONFIG_TRACER_MAX_TRACE */
736
737 #ifdef LATENCY_FS_NOTIFY
738 void latency_fsnotify(struct trace_array *tr);
739 #else
740 static inline void latency_fsnotify(struct trace_array *tr) { }
741 #endif
742
743 #ifdef CONFIG_STACKTRACE
744 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
745 #else
746 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
747 int skip)
748 {
749 }
750 #endif /* CONFIG_STACKTRACE */
751
752 void trace_last_func_repeats(struct trace_array *tr,
753 struct trace_func_repeats *last_info,
754 unsigned int trace_ctx);
755
756 extern u64 ftrace_now(int cpu);
757
758 extern void trace_find_cmdline(int pid, char comm[]);
759 extern int trace_find_tgid(int pid);
760 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
761
762 #ifdef CONFIG_DYNAMIC_FTRACE
763 extern unsigned long ftrace_update_tot_cnt;
764 extern unsigned long ftrace_number_of_pages;
765 extern unsigned long ftrace_number_of_groups;
766 void ftrace_init_trace_array(struct trace_array *tr);
767 #else
768 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
769 #endif
770 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
771 extern int DYN_FTRACE_TEST_NAME(void);
772 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
773 extern int DYN_FTRACE_TEST_NAME2(void);
774
775 extern void trace_set_ring_buffer_expanded(struct trace_array *tr);
776 extern bool tracing_selftest_disabled;
777
778 #ifdef CONFIG_FTRACE_STARTUP_TEST
779 extern void __init disable_tracing_selftest(const char *reason);
780
781 extern int trace_selftest_startup_function(struct tracer *trace,
782 struct trace_array *tr);
783 extern int trace_selftest_startup_function_graph(struct tracer *trace,
784 struct trace_array *tr);
785 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
786 struct trace_array *tr);
787 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
788 struct trace_array *tr);
789 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
790 struct trace_array *tr);
791 extern int trace_selftest_startup_wakeup(struct tracer *trace,
792 struct trace_array *tr);
793 extern int trace_selftest_startup_nop(struct tracer *trace,
794 struct trace_array *tr);
795 extern int trace_selftest_startup_branch(struct tracer *trace,
796 struct trace_array *tr);
797 /*
798 * Tracer data references selftest functions that only occur
799 * on boot up. These can be __init functions. Thus, when selftests
800 * are enabled, then the tracers need to reference __init functions.
801 */
802 #define __tracer_data __refdata
803 #else
804 static inline void __init disable_tracing_selftest(const char *reason)
805 {
806 }
807 /* Tracers are seldom changed. Optimize when selftests are disabled. */
808 #define __tracer_data __read_mostly
809 #endif /* CONFIG_FTRACE_STARTUP_TEST */
810
811 extern void *head_page(struct trace_array_cpu *data);
812 extern unsigned long long ns2usecs(u64 nsec);
813 extern int
814 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
815 extern int
816 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
817 extern int
818 trace_array_vprintk(struct trace_array *tr,
819 unsigned long ip, const char *fmt, va_list args);
820 int trace_array_printk_buf(struct trace_buffer *buffer,
821 unsigned long ip, const char *fmt, ...);
822 void trace_printk_seq(struct trace_seq *s);
823 enum print_line_t print_trace_line(struct trace_iterator *iter);
824
825 extern char trace_find_mark(unsigned long long duration);
826
827 struct ftrace_hash;
828
829 struct ftrace_mod_load {
830 struct list_head list;
831 char *func;
832 char *module;
833 int enable;
834 };
835
836 enum {
837 FTRACE_HASH_FL_MOD = (1 << 0),
838 };
839
840 struct ftrace_hash {
841 unsigned long size_bits;
842 struct hlist_head *buckets;
843 unsigned long count;
844 unsigned long flags;
845 struct rcu_head rcu;
846 };
847
848 struct ftrace_func_entry *
849 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
850
851 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
852 {
853 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
854 }
855
856 /* Standard output formatting function used for function return traces */
857 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
858
859 /* Flag options */
860 #define TRACE_GRAPH_PRINT_OVERRUN 0x1
861 #define TRACE_GRAPH_PRINT_CPU 0x2
862 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4
863 #define TRACE_GRAPH_PRINT_PROC 0x8
864 #define TRACE_GRAPH_PRINT_DURATION 0x10
865 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20
866 #define TRACE_GRAPH_PRINT_REL_TIME 0x40
867 #define TRACE_GRAPH_PRINT_IRQS 0x80
868 #define TRACE_GRAPH_PRINT_TAIL 0x100
869 #define TRACE_GRAPH_SLEEP_TIME 0x200
870 #define TRACE_GRAPH_GRAPH_TIME 0x400
871 #define TRACE_GRAPH_PRINT_RETVAL 0x800
872 #define TRACE_GRAPH_PRINT_RETVAL_HEX 0x1000
873 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28
874 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
875
876 extern void ftrace_graph_sleep_time_control(bool enable);
877
878 #ifdef CONFIG_FUNCTION_PROFILER
879 extern void ftrace_graph_graph_time_control(bool enable);
880 #else
881 static inline void ftrace_graph_graph_time_control(bool enable) { }
882 #endif
883
884 extern enum print_line_t
885 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
886 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
887 extern void
888 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
889 extern void graph_trace_open(struct trace_iterator *iter);
890 extern void graph_trace_close(struct trace_iterator *iter);
891 extern int __trace_graph_entry(struct trace_array *tr,
892 struct ftrace_graph_ent *trace,
893 unsigned int trace_ctx);
894 extern void __trace_graph_return(struct trace_array *tr,
895 struct ftrace_graph_ret *trace,
896 unsigned int trace_ctx);
897 extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
898 extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
899 extern void free_fgraph_ops(struct trace_array *tr);
900
901 enum {
902 TRACE_GRAPH_FL = 1,
903
904 /*
905 * In the very unlikely case that an interrupt came in
906 * at a start of graph tracing, and we want to trace
907 * the function in that interrupt, the depth can be greater
908 * than zero, because of the preempted start of a previous
909 * trace. In an even more unlikely case, depth could be 2
910 * if a softirq interrupted the start of graph tracing,
911 * followed by an interrupt preempting a start of graph
912 * tracing in the softirq, and depth can even be 3
913 * if an NMI came in at the start of an interrupt function
914 * that preempted a softirq start of a function that
915 * preempted normal context!!!! Luckily, it can't be
916 * greater than 3, so the next two bits are a mask
917 * of what the depth is when we set TRACE_GRAPH_FL
918 */
919
920 TRACE_GRAPH_DEPTH_START_BIT,
921 TRACE_GRAPH_DEPTH_END_BIT,
922
923 /*
924 * To implement set_graph_notrace, if this bit is set, we ignore
925 * function graph tracing of called functions, until the return
926 * function is called to clear it.
927 */
928 TRACE_GRAPH_NOTRACE_BIT,
929 };
930
931 #define TRACE_GRAPH_NOTRACE (1 << TRACE_GRAPH_NOTRACE_BIT)
932
933 static inline unsigned long ftrace_graph_depth(unsigned long *task_var)
934 {
935 return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3;
936 }
937
938 static inline void ftrace_graph_set_depth(unsigned long *task_var, int depth)
939 {
940 *task_var &= ~(3 << TRACE_GRAPH_DEPTH_START_BIT);
941 *task_var |= (depth & 3) << TRACE_GRAPH_DEPTH_START_BIT;
942 }
943
944 #ifdef CONFIG_DYNAMIC_FTRACE
945 extern struct ftrace_hash __rcu *ftrace_graph_hash;
946 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
947
948 static inline int
949 ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
950 {
951 unsigned long addr = trace->func;
952 int ret = 0;
953 struct ftrace_hash *hash;
954
955 preempt_disable_notrace();
956
957 /*
958 * Have to open code "rcu_dereference_sched()" because the
959 * function graph tracer can be called when RCU is not
960 * "watching".
961 * Protected with schedule_on_each_cpu(ftrace_sync)
962 */
963 hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
964
965 if (ftrace_hash_empty(hash)) {
966 ret = 1;
967 goto out;
968 }
969
970 if (ftrace_lookup_ip(hash, addr)) {
971 /*
972 * This needs to be cleared on the return functions
973 * when the depth is zero.
974 */
975 *task_var |= TRACE_GRAPH_FL;
976 ftrace_graph_set_depth(task_var, trace->depth);
977
978 /*
979 * If no irqs are to be traced, but a set_graph_function
980 * is set, and called by an interrupt handler, we still
981 * want to trace it.
982 */
983 if (in_hardirq())
984 trace_recursion_set(TRACE_IRQ_BIT);
985 else
986 trace_recursion_clear(TRACE_IRQ_BIT);
987 ret = 1;
988 }
989
990 out:
991 preempt_enable_notrace();
992 return ret;
993 }
994
995 static inline void
996 ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
997 {
998 unsigned long *task_var = fgraph_get_task_var(gops);
999
1000 if ((*task_var & TRACE_GRAPH_FL) &&
1001 trace->depth == ftrace_graph_depth(task_var))
1002 *task_var &= ~TRACE_GRAPH_FL;
1003 }
1004
1005 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1006 {
1007 int ret = 0;
1008 struct ftrace_hash *notrace_hash;
1009
1010 preempt_disable_notrace();
1011
1012 /*
1013 * Have to open code "rcu_dereference_sched()" because the
1014 * function graph tracer can be called when RCU is not
1015 * "watching".
1016 * Protected with schedule_on_each_cpu(ftrace_sync)
1017 */
1018 notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
1019 !preemptible());
1020
1021 if (ftrace_lookup_ip(notrace_hash, addr))
1022 ret = 1;
1023
1024 preempt_enable_notrace();
1025 return ret;
1026 }
1027 #else
1028 static inline int ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
1029 {
1030 return 1;
1031 }
1032
1033 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1034 {
1035 return 0;
1036 }
1037 static inline void ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1038 { }
1039 #endif /* CONFIG_DYNAMIC_FTRACE */
1040
1041 extern unsigned int fgraph_max_depth;
1042
1043 static inline bool
1044 ftrace_graph_ignore_func(struct fgraph_ops *gops, struct ftrace_graph_ent *trace)
1045 {
1046 unsigned long *task_var = fgraph_get_task_var(gops);
1047
1048 /* trace it when it is-nested-in or is a function enabled. */
1049 return !((*task_var & TRACE_GRAPH_FL) ||
1050 ftrace_graph_addr(task_var, trace)) ||
1051 (trace->depth < 0) ||
1052 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
1053 }
1054
1055 void fgraph_init_ops(struct ftrace_ops *dst_ops,
1056 struct ftrace_ops *src_ops);
1057
1058 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
1059 static inline enum print_line_t
1060 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1061 {
1062 return TRACE_TYPE_UNHANDLED;
1063 }
1064 static inline void free_fgraph_ops(struct trace_array *tr) { }
1065 /* ftrace_ops may not be defined */
1066 #define init_array_fgraph_ops(tr, ops) do { } while (0)
1067 #define allocate_fgraph_ops(tr, ops) ({ 0; })
1068 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1069
1070 extern struct list_head ftrace_pids;
1071
1072 #ifdef CONFIG_FUNCTION_TRACER
1073
1074 #define FTRACE_PID_IGNORE -1
1075 #define FTRACE_PID_TRACE -2
1076
1077 struct ftrace_func_command {
1078 struct list_head list;
1079 char *name;
1080 int (*func)(struct trace_array *tr,
1081 struct ftrace_hash *hash,
1082 char *func, char *cmd,
1083 char *params, int enable);
1084 };
1085 extern bool ftrace_filter_param __initdata;
1086 static inline int ftrace_trace_task(struct trace_array *tr)
1087 {
1088 return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1089 FTRACE_PID_IGNORE;
1090 }
1091 extern int ftrace_is_dead(void);
1092 int ftrace_create_function_files(struct trace_array *tr,
1093 struct dentry *parent);
1094 void ftrace_destroy_function_files(struct trace_array *tr);
1095 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1096 void ftrace_free_ftrace_ops(struct trace_array *tr);
1097 void ftrace_init_global_array_ops(struct trace_array *tr);
1098 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1099 void ftrace_reset_array_ops(struct trace_array *tr);
1100 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1101 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1102 struct dentry *d_tracer);
1103 void ftrace_clear_pids(struct trace_array *tr);
1104 int init_function_trace(void);
1105 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1106 #else
1107 static inline int ftrace_trace_task(struct trace_array *tr)
1108 {
1109 return 1;
1110 }
1111 static inline int ftrace_is_dead(void) { return 0; }
1112 static inline int
1113 ftrace_create_function_files(struct trace_array *tr,
1114 struct dentry *parent)
1115 {
1116 return 0;
1117 }
1118 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1119 {
1120 return 0;
1121 }
1122 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1123 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1124 static inline __init void
1125 ftrace_init_global_array_ops(struct trace_array *tr) { }
1126 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1127 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1128 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1129 static inline void ftrace_clear_pids(struct trace_array *tr) { }
1130 static inline int init_function_trace(void) { return 0; }
1131 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1132 /* ftace_func_t type is not defined, use macro instead of static inline */
1133 #define ftrace_init_array_ops(tr, func) do { } while (0)
1134 #endif /* CONFIG_FUNCTION_TRACER */
1135
1136 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1137
1138 struct ftrace_probe_ops {
1139 void (*func)(unsigned long ip,
1140 unsigned long parent_ip,
1141 struct trace_array *tr,
1142 struct ftrace_probe_ops *ops,
1143 void *data);
1144 int (*init)(struct ftrace_probe_ops *ops,
1145 struct trace_array *tr,
1146 unsigned long ip, void *init_data,
1147 void **data);
1148 void (*free)(struct ftrace_probe_ops *ops,
1149 struct trace_array *tr,
1150 unsigned long ip, void *data);
1151 int (*print)(struct seq_file *m,
1152 unsigned long ip,
1153 struct ftrace_probe_ops *ops,
1154 void *data);
1155 };
1156
1157 struct ftrace_func_mapper;
1158 typedef int (*ftrace_mapper_func)(void *data);
1159
1160 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1161 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1162 unsigned long ip);
1163 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1164 unsigned long ip, void *data);
1165 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1166 unsigned long ip);
1167 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1168 ftrace_mapper_func free_func);
1169
1170 extern int
1171 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1172 struct ftrace_probe_ops *ops, void *data);
1173 extern int
1174 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1175 struct ftrace_probe_ops *ops);
1176 extern void clear_ftrace_function_probes(struct trace_array *tr);
1177
1178 int register_ftrace_command(struct ftrace_func_command *cmd);
1179 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1180
1181 void ftrace_create_filter_files(struct ftrace_ops *ops,
1182 struct dentry *parent);
1183 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1184
1185 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1186 int len, int reset);
1187 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1188 int len, int reset);
1189 #else
1190 struct ftrace_func_command;
1191
1192 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1193 {
1194 return -EINVAL;
1195 }
1196 static inline __init int unregister_ftrace_command(char *cmd_name)
1197 {
1198 return -EINVAL;
1199 }
1200 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1201 {
1202 }
1203
1204 /*
1205 * The ops parameter passed in is usually undefined.
1206 * This must be a macro.
1207 */
1208 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1209 #define ftrace_destroy_filter_files(ops) do { } while (0)
1210 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1211
1212 bool ftrace_event_is_function(struct trace_event_call *call);
1213
1214 /*
1215 * struct trace_parser - servers for reading the user input separated by spaces
1216 * @cont: set if the input is not complete - no final space char was found
1217 * @buffer: holds the parsed user input
1218 * @idx: user input length
1219 * @size: buffer size
1220 */
1221 struct trace_parser {
1222 bool cont;
1223 char *buffer;
1224 unsigned idx;
1225 unsigned size;
1226 };
1227
1228 static inline bool trace_parser_loaded(struct trace_parser *parser)
1229 {
1230 return (parser->idx != 0);
1231 }
1232
1233 static inline bool trace_parser_cont(struct trace_parser *parser)
1234 {
1235 return parser->cont;
1236 }
1237
1238 static inline void trace_parser_clear(struct trace_parser *parser)
1239 {
1240 parser->cont = false;
1241 parser->idx = 0;
1242 }
1243
1244 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1245 extern void trace_parser_put(struct trace_parser *parser);
1246 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1247 size_t cnt, loff_t *ppos);
1248
1249 /*
1250 * Only create function graph options if function graph is configured.
1251 */
1252 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1253 # define FGRAPH_FLAGS \
1254 C(DISPLAY_GRAPH, "display-graph"),
1255 #else
1256 # define FGRAPH_FLAGS
1257 #endif
1258
1259 #ifdef CONFIG_BRANCH_TRACER
1260 # define BRANCH_FLAGS \
1261 C(BRANCH, "branch"),
1262 #else
1263 # define BRANCH_FLAGS
1264 #endif
1265
1266 #ifdef CONFIG_FUNCTION_TRACER
1267 # define FUNCTION_FLAGS \
1268 C(FUNCTION, "function-trace"), \
1269 C(FUNC_FORK, "function-fork"),
1270 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1271 #else
1272 # define FUNCTION_FLAGS
1273 # define FUNCTION_DEFAULT_FLAGS 0UL
1274 # define TRACE_ITER_FUNC_FORK 0UL
1275 #endif
1276
1277 #ifdef CONFIG_STACKTRACE
1278 # define STACK_FLAGS \
1279 C(STACKTRACE, "stacktrace"),
1280 #else
1281 # define STACK_FLAGS
1282 #endif
1283
1284 /*
1285 * trace_iterator_flags is an enumeration that defines bit
1286 * positions into trace_flags that controls the output.
1287 *
1288 * NOTE: These bits must match the trace_options array in
1289 * trace.c (this macro guarantees it).
1290 */
1291 #define TRACE_FLAGS \
1292 C(PRINT_PARENT, "print-parent"), \
1293 C(SYM_OFFSET, "sym-offset"), \
1294 C(SYM_ADDR, "sym-addr"), \
1295 C(VERBOSE, "verbose"), \
1296 C(RAW, "raw"), \
1297 C(HEX, "hex"), \
1298 C(BIN, "bin"), \
1299 C(BLOCK, "block"), \
1300 C(FIELDS, "fields"), \
1301 C(PRINTK, "trace_printk"), \
1302 C(ANNOTATE, "annotate"), \
1303 C(USERSTACKTRACE, "userstacktrace"), \
1304 C(SYM_USEROBJ, "sym-userobj"), \
1305 C(PRINTK_MSGONLY, "printk-msg-only"), \
1306 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1307 C(LATENCY_FMT, "latency-format"), \
1308 C(RECORD_CMD, "record-cmd"), \
1309 C(RECORD_TGID, "record-tgid"), \
1310 C(OVERWRITE, "overwrite"), \
1311 C(STOP_ON_FREE, "disable_on_free"), \
1312 C(IRQ_INFO, "irq-info"), \
1313 C(MARKERS, "markers"), \
1314 C(EVENT_FORK, "event-fork"), \
1315 C(PAUSE_ON_TRACE, "pause-on-trace"), \
1316 C(HASH_PTR, "hash-ptr"), /* Print hashed pointer */ \
1317 FUNCTION_FLAGS \
1318 FGRAPH_FLAGS \
1319 STACK_FLAGS \
1320 BRANCH_FLAGS
1321
1322 /*
1323 * By defining C, we can make TRACE_FLAGS a list of bit names
1324 * that will define the bits for the flag masks.
1325 */
1326 #undef C
1327 #define C(a, b) TRACE_ITER_##a##_BIT
1328
1329 enum trace_iterator_bits {
1330 TRACE_FLAGS
1331 /* Make sure we don't go more than we have bits for */
1332 TRACE_ITER_LAST_BIT
1333 };
1334
1335 /*
1336 * By redefining C, we can make TRACE_FLAGS a list of masks that
1337 * use the bits as defined above.
1338 */
1339 #undef C
1340 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1341
1342 enum trace_iterator_flags { TRACE_FLAGS };
1343
1344 /*
1345 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1346 * control the output of kernel symbols.
1347 */
1348 #define TRACE_ITER_SYM_MASK \
1349 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1350
1351 extern struct tracer nop_trace;
1352
1353 #ifdef CONFIG_BRANCH_TRACER
1354 extern int enable_branch_tracing(struct trace_array *tr);
1355 extern void disable_branch_tracing(void);
1356 static inline int trace_branch_enable(struct trace_array *tr)
1357 {
1358 if (tr->trace_flags & TRACE_ITER_BRANCH)
1359 return enable_branch_tracing(tr);
1360 return 0;
1361 }
1362 static inline void trace_branch_disable(void)
1363 {
1364 /* due to races, always disable */
1365 disable_branch_tracing();
1366 }
1367 #else
1368 static inline int trace_branch_enable(struct trace_array *tr)
1369 {
1370 return 0;
1371 }
1372 static inline void trace_branch_disable(void)
1373 {
1374 }
1375 #endif /* CONFIG_BRANCH_TRACER */
1376
1377 /* set ring buffers to default size if not already done so */
1378 int tracing_update_buffers(struct trace_array *tr);
1379
1380 union trace_synth_field {
1381 u8 as_u8;
1382 u16 as_u16;
1383 u32 as_u32;
1384 u64 as_u64;
1385 struct trace_dynamic_info as_dynamic;
1386 };
1387
1388 struct ftrace_event_field {
1389 struct list_head link;
1390 const char *name;
1391 const char *type;
1392 int filter_type;
1393 int offset;
1394 int size;
1395 int is_signed;
1396 int len;
1397 };
1398
1399 struct prog_entry;
1400
1401 struct event_filter {
1402 struct prog_entry __rcu *prog;
1403 char *filter_string;
1404 };
1405
1406 struct event_subsystem {
1407 struct list_head list;
1408 const char *name;
1409 struct event_filter *filter;
1410 int ref_count;
1411 };
1412
1413 struct trace_subsystem_dir {
1414 struct list_head list;
1415 struct event_subsystem *subsystem;
1416 struct trace_array *tr;
1417 struct eventfs_inode *ei;
1418 int ref_count;
1419 int nr_events;
1420 };
1421
1422 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1423 struct trace_buffer *buffer,
1424 struct ring_buffer_event *event);
1425
1426 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1427 struct trace_buffer *buffer,
1428 struct ring_buffer_event *event,
1429 unsigned int trcace_ctx,
1430 struct pt_regs *regs);
1431
1432 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1433 struct trace_buffer *buffer,
1434 struct ring_buffer_event *event,
1435 unsigned int trace_ctx)
1436 {
1437 trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1438 }
1439
1440 DECLARE_PER_CPU(bool, trace_taskinfo_save);
1441 int trace_save_cmdline(struct task_struct *tsk);
1442 int trace_create_savedcmd(void);
1443 int trace_alloc_tgid_map(void);
1444 void trace_free_saved_cmdlines_buffer(void);
1445
1446 extern const struct file_operations tracing_saved_cmdlines_fops;
1447 extern const struct file_operations tracing_saved_tgids_fops;
1448 extern const struct file_operations tracing_saved_cmdlines_size_fops;
1449
1450 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1451 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1452 void trace_buffered_event_disable(void);
1453 void trace_buffered_event_enable(void);
1454
1455 void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1456
1457 static inline void
1458 __trace_event_discard_commit(struct trace_buffer *buffer,
1459 struct ring_buffer_event *event)
1460 {
1461 if (this_cpu_read(trace_buffered_event) == event) {
1462 /* Simply release the temp buffer and enable preemption */
1463 this_cpu_dec(trace_buffered_event_cnt);
1464 preempt_enable_notrace();
1465 return;
1466 }
1467 /* ring_buffer_discard_commit() enables preemption */
1468 ring_buffer_discard_commit(buffer, event);
1469 }
1470
1471 /*
1472 * Helper function for event_trigger_unlock_commit{_regs}().
1473 * If there are event triggers attached to this event that requires
1474 * filtering against its fields, then they will be called as the
1475 * entry already holds the field information of the current event.
1476 *
1477 * It also checks if the event should be discarded or not.
1478 * It is to be discarded if the event is soft disabled and the
1479 * event was only recorded to process triggers, or if the event
1480 * filter is active and this event did not match the filters.
1481 *
1482 * Returns true if the event is discarded, false otherwise.
1483 */
1484 static inline bool
1485 __event_trigger_test_discard(struct trace_event_file *file,
1486 struct trace_buffer *buffer,
1487 struct ring_buffer_event *event,
1488 void *entry,
1489 enum event_trigger_type *tt)
1490 {
1491 unsigned long eflags = file->flags;
1492
1493 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1494 *tt = event_triggers_call(file, buffer, entry, event);
1495
1496 if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1497 EVENT_FILE_FL_FILTERED |
1498 EVENT_FILE_FL_PID_FILTER))))
1499 return false;
1500
1501 if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1502 goto discard;
1503
1504 if (file->flags & EVENT_FILE_FL_FILTERED &&
1505 !filter_match_preds(file->filter, entry))
1506 goto discard;
1507
1508 if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1509 trace_event_ignore_this_pid(file))
1510 goto discard;
1511
1512 return false;
1513 discard:
1514 __trace_event_discard_commit(buffer, event);
1515 return true;
1516 }
1517
1518 /**
1519 * event_trigger_unlock_commit - handle triggers and finish event commit
1520 * @file: The file pointer associated with the event
1521 * @buffer: The ring buffer that the event is being written to
1522 * @event: The event meta data in the ring buffer
1523 * @entry: The event itself
1524 * @trace_ctx: The tracing context flags.
1525 *
1526 * This is a helper function to handle triggers that require data
1527 * from the event itself. It also tests the event against filters and
1528 * if the event is soft disabled and should be discarded.
1529 */
1530 static inline void
1531 event_trigger_unlock_commit(struct trace_event_file *file,
1532 struct trace_buffer *buffer,
1533 struct ring_buffer_event *event,
1534 void *entry, unsigned int trace_ctx)
1535 {
1536 enum event_trigger_type tt = ETT_NONE;
1537
1538 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1539 trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1540
1541 if (tt)
1542 event_triggers_post_call(file, tt);
1543 }
1544
1545 #define FILTER_PRED_INVALID ((unsigned short)-1)
1546 #define FILTER_PRED_IS_RIGHT (1 << 15)
1547 #define FILTER_PRED_FOLD (1 << 15)
1548
1549 /*
1550 * The max preds is the size of unsigned short with
1551 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1552 * and FOLD flags. The other is reserved.
1553 *
1554 * 2^14 preds is way more than enough.
1555 */
1556 #define MAX_FILTER_PRED 16384
1557
1558 struct filter_pred;
1559 struct regex;
1560
1561 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1562
1563 enum regex_type {
1564 MATCH_FULL = 0,
1565 MATCH_FRONT_ONLY,
1566 MATCH_MIDDLE_ONLY,
1567 MATCH_END_ONLY,
1568 MATCH_GLOB,
1569 MATCH_INDEX,
1570 };
1571
1572 struct regex {
1573 char pattern[MAX_FILTER_STR_VAL];
1574 int len;
1575 int field_len;
1576 regex_match_func match;
1577 };
1578
1579 static inline bool is_string_field(struct ftrace_event_field *field)
1580 {
1581 return field->filter_type == FILTER_DYN_STRING ||
1582 field->filter_type == FILTER_RDYN_STRING ||
1583 field->filter_type == FILTER_STATIC_STRING ||
1584 field->filter_type == FILTER_PTR_STRING ||
1585 field->filter_type == FILTER_COMM;
1586 }
1587
1588 static inline bool is_function_field(struct ftrace_event_field *field)
1589 {
1590 return field->filter_type == FILTER_TRACE_FN;
1591 }
1592
1593 extern enum regex_type
1594 filter_parse_regex(char *buff, int len, char **search, int *not);
1595 extern void print_event_filter(struct trace_event_file *file,
1596 struct trace_seq *s);
1597 extern int apply_event_filter(struct trace_event_file *file,
1598 char *filter_string);
1599 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1600 char *filter_string);
1601 extern void print_subsystem_event_filter(struct event_subsystem *system,
1602 struct trace_seq *s);
1603 extern int filter_assign_type(const char *type);
1604 extern int create_event_filter(struct trace_array *tr,
1605 struct trace_event_call *call,
1606 char *filter_str, bool set_str,
1607 struct event_filter **filterp);
1608 extern void free_event_filter(struct event_filter *filter);
1609
1610 struct ftrace_event_field *
1611 trace_find_event_field(struct trace_event_call *call, char *name);
1612
1613 extern void trace_event_enable_cmd_record(bool enable);
1614 extern void trace_event_enable_tgid_record(bool enable);
1615
1616 extern int event_trace_init(void);
1617 extern int init_events(void);
1618 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1619 extern int event_trace_del_tracer(struct trace_array *tr);
1620 extern void __trace_early_add_events(struct trace_array *tr);
1621
1622 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1623 const char *system,
1624 const char *event);
1625 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1626 const char *system,
1627 const char *event);
1628
1629 static inline void *event_file_data(struct file *filp)
1630 {
1631 return READ_ONCE(file_inode(filp)->i_private);
1632 }
1633
1634 extern struct mutex event_mutex;
1635 extern struct list_head ftrace_events;
1636
1637 /*
1638 * When the trace_event_file is the filp->i_private pointer,
1639 * it must be taken under the event_mutex lock, and then checked
1640 * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
1641 * data pointed to by the trace_event_file can not be trusted.
1642 *
1643 * Use the event_file_file() to access the trace_event_file from
1644 * the filp the first time under the event_mutex and check for
1645 * NULL. If it is needed to be retrieved again and the event_mutex
1646 * is still held, then the event_file_data() can be used and it
1647 * is guaranteed to be valid.
1648 */
1649 static inline struct trace_event_file *event_file_file(struct file *filp)
1650 {
1651 struct trace_event_file *file;
1652
1653 lockdep_assert_held(&event_mutex);
1654 file = READ_ONCE(file_inode(filp)->i_private);
1655 if (!file || file->flags & EVENT_FILE_FL_FREED)
1656 return NULL;
1657 return file;
1658 }
1659
1660 extern const struct file_operations event_trigger_fops;
1661 extern const struct file_operations event_hist_fops;
1662 extern const struct file_operations event_hist_debug_fops;
1663 extern const struct file_operations event_inject_fops;
1664
1665 #ifdef CONFIG_HIST_TRIGGERS
1666 extern int register_trigger_hist_cmd(void);
1667 extern int register_trigger_hist_enable_disable_cmds(void);
1668 #else
1669 static inline int register_trigger_hist_cmd(void) { return 0; }
1670 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1671 #endif
1672
1673 extern int register_trigger_cmds(void);
1674 extern void clear_event_triggers(struct trace_array *tr);
1675
1676 enum {
1677 EVENT_TRIGGER_FL_PROBE = BIT(0),
1678 };
1679
1680 struct event_trigger_data {
1681 unsigned long count;
1682 int ref;
1683 int flags;
1684 struct event_trigger_ops *ops;
1685 struct event_command *cmd_ops;
1686 struct event_filter __rcu *filter;
1687 char *filter_str;
1688 void *private_data;
1689 bool paused;
1690 bool paused_tmp;
1691 struct list_head list;
1692 char *name;
1693 struct list_head named_list;
1694 struct event_trigger_data *named_data;
1695 };
1696
1697 /* Avoid typos */
1698 #define ENABLE_EVENT_STR "enable_event"
1699 #define DISABLE_EVENT_STR "disable_event"
1700 #define ENABLE_HIST_STR "enable_hist"
1701 #define DISABLE_HIST_STR "disable_hist"
1702
1703 struct enable_trigger_data {
1704 struct trace_event_file *file;
1705 bool enable;
1706 bool hist;
1707 };
1708
1709 extern int event_enable_trigger_print(struct seq_file *m,
1710 struct event_trigger_data *data);
1711 extern void event_enable_trigger_free(struct event_trigger_data *data);
1712 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1713 struct trace_event_file *file,
1714 char *glob, char *cmd,
1715 char *param_and_filter);
1716 extern int event_enable_register_trigger(char *glob,
1717 struct event_trigger_data *data,
1718 struct trace_event_file *file);
1719 extern void event_enable_unregister_trigger(char *glob,
1720 struct event_trigger_data *test,
1721 struct trace_event_file *file);
1722 extern void trigger_data_free(struct event_trigger_data *data);
1723 extern int event_trigger_init(struct event_trigger_data *data);
1724 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1725 int trigger_enable);
1726 extern void update_cond_flag(struct trace_event_file *file);
1727 extern int set_trigger_filter(char *filter_str,
1728 struct event_trigger_data *trigger_data,
1729 struct trace_event_file *file);
1730 extern struct event_trigger_data *find_named_trigger(const char *name);
1731 extern bool is_named_trigger(struct event_trigger_data *test);
1732 extern int save_named_trigger(const char *name,
1733 struct event_trigger_data *data);
1734 extern void del_named_trigger(struct event_trigger_data *data);
1735 extern void pause_named_trigger(struct event_trigger_data *data);
1736 extern void unpause_named_trigger(struct event_trigger_data *data);
1737 extern void set_named_trigger_data(struct event_trigger_data *data,
1738 struct event_trigger_data *named_data);
1739 extern struct event_trigger_data *
1740 get_named_trigger_data(struct event_trigger_data *data);
1741 extern int register_event_command(struct event_command *cmd);
1742 extern int unregister_event_command(struct event_command *cmd);
1743 extern int register_trigger_hist_enable_disable_cmds(void);
1744 extern bool event_trigger_check_remove(const char *glob);
1745 extern bool event_trigger_empty_param(const char *param);
1746 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1747 char **filter, bool param_required);
1748 extern struct event_trigger_data *
1749 event_trigger_alloc(struct event_command *cmd_ops,
1750 char *cmd,
1751 char *param,
1752 void *private_data);
1753 extern int event_trigger_parse_num(char *trigger,
1754 struct event_trigger_data *trigger_data);
1755 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1756 struct trace_event_file *file,
1757 char *param,
1758 struct event_trigger_data *trigger_data);
1759 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1760 struct event_trigger_data *trigger_data);
1761 extern int event_trigger_register(struct event_command *cmd_ops,
1762 struct trace_event_file *file,
1763 char *glob,
1764 struct event_trigger_data *trigger_data);
1765 extern void event_trigger_unregister(struct event_command *cmd_ops,
1766 struct trace_event_file *file,
1767 char *glob,
1768 struct event_trigger_data *trigger_data);
1769
1770 extern void event_file_get(struct trace_event_file *file);
1771 extern void event_file_put(struct trace_event_file *file);
1772
1773 /**
1774 * struct event_trigger_ops - callbacks for trace event triggers
1775 *
1776 * The methods in this structure provide per-event trigger hooks for
1777 * various trigger operations.
1778 *
1779 * The @init and @free methods are used during trigger setup and
1780 * teardown, typically called from an event_command's @parse()
1781 * function implementation.
1782 *
1783 * The @print method is used to print the trigger spec.
1784 *
1785 * The @trigger method is the function that actually implements the
1786 * trigger and is called in the context of the triggering event
1787 * whenever that event occurs.
1788 *
1789 * All the methods below, except for @init() and @free(), must be
1790 * implemented.
1791 *
1792 * @trigger: The trigger 'probe' function called when the triggering
1793 * event occurs. The data passed into this callback is the data
1794 * that was supplied to the event_command @reg() function that
1795 * registered the trigger (see struct event_command) along with
1796 * the trace record, rec.
1797 *
1798 * @init: An optional initialization function called for the trigger
1799 * when the trigger is registered (via the event_command reg()
1800 * function). This can be used to perform per-trigger
1801 * initialization such as incrementing a per-trigger reference
1802 * count, for instance. This is usually implemented by the
1803 * generic utility function @event_trigger_init() (see
1804 * trace_event_triggers.c).
1805 *
1806 * @free: An optional de-initialization function called for the
1807 * trigger when the trigger is unregistered (via the
1808 * event_command @reg() function). This can be used to perform
1809 * per-trigger de-initialization such as decrementing a
1810 * per-trigger reference count and freeing corresponding trigger
1811 * data, for instance. This is usually implemented by the
1812 * generic utility function @event_trigger_free() (see
1813 * trace_event_triggers.c).
1814 *
1815 * @print: The callback function invoked to have the trigger print
1816 * itself. This is usually implemented by a wrapper function
1817 * that calls the generic utility function @event_trigger_print()
1818 * (see trace_event_triggers.c).
1819 */
1820 struct event_trigger_ops {
1821 void (*trigger)(struct event_trigger_data *data,
1822 struct trace_buffer *buffer,
1823 void *rec,
1824 struct ring_buffer_event *rbe);
1825 int (*init)(struct event_trigger_data *data);
1826 void (*free)(struct event_trigger_data *data);
1827 int (*print)(struct seq_file *m,
1828 struct event_trigger_data *data);
1829 };
1830
1831 /**
1832 * struct event_command - callbacks and data members for event commands
1833 *
1834 * Event commands are invoked by users by writing the command name
1835 * into the 'trigger' file associated with a trace event. The
1836 * parameters associated with a specific invocation of an event
1837 * command are used to create an event trigger instance, which is
1838 * added to the list of trigger instances associated with that trace
1839 * event. When the event is hit, the set of triggers associated with
1840 * that event is invoked.
1841 *
1842 * The data members in this structure provide per-event command data
1843 * for various event commands.
1844 *
1845 * All the data members below, except for @post_trigger, must be set
1846 * for each event command.
1847 *
1848 * @name: The unique name that identifies the event command. This is
1849 * the name used when setting triggers via trigger files.
1850 *
1851 * @trigger_type: A unique id that identifies the event command
1852 * 'type'. This value has two purposes, the first to ensure that
1853 * only one trigger of the same type can be set at a given time
1854 * for a particular event e.g. it doesn't make sense to have both
1855 * a traceon and traceoff trigger attached to a single event at
1856 * the same time, so traceon and traceoff have the same type
1857 * though they have different names. The @trigger_type value is
1858 * also used as a bit value for deferring the actual trigger
1859 * action until after the current event is finished. Some
1860 * commands need to do this if they themselves log to the trace
1861 * buffer (see the @post_trigger() member below). @trigger_type
1862 * values are defined by adding new values to the trigger_type
1863 * enum in include/linux/trace_events.h.
1864 *
1865 * @flags: See the enum event_command_flags below.
1866 *
1867 * All the methods below, except for @set_filter() and @unreg_all(),
1868 * must be implemented.
1869 *
1870 * @parse: The callback function responsible for parsing and
1871 * registering the trigger written to the 'trigger' file by the
1872 * user. It allocates the trigger instance and registers it with
1873 * the appropriate trace event. It makes use of the other
1874 * event_command callback functions to orchestrate this, and is
1875 * usually implemented by the generic utility function
1876 * @event_trigger_callback() (see trace_event_triggers.c).
1877 *
1878 * @reg: Adds the trigger to the list of triggers associated with the
1879 * event, and enables the event trigger itself, after
1880 * initializing it (via the event_trigger_ops @init() function).
1881 * This is also where commands can use the @trigger_type value to
1882 * make the decision as to whether or not multiple instances of
1883 * the trigger should be allowed. This is usually implemented by
1884 * the generic utility function @register_trigger() (see
1885 * trace_event_triggers.c).
1886 *
1887 * @unreg: Removes the trigger from the list of triggers associated
1888 * with the event, and disables the event trigger itself, after
1889 * initializing it (via the event_trigger_ops @free() function).
1890 * This is usually implemented by the generic utility function
1891 * @unregister_trigger() (see trace_event_triggers.c).
1892 *
1893 * @unreg_all: An optional function called to remove all the triggers
1894 * from the list of triggers associated with the event. Called
1895 * when a trigger file is opened in truncate mode.
1896 *
1897 * @set_filter: An optional function called to parse and set a filter
1898 * for the trigger. If no @set_filter() method is set for the
1899 * event command, filters set by the user for the command will be
1900 * ignored. This is usually implemented by the generic utility
1901 * function @set_trigger_filter() (see trace_event_triggers.c).
1902 *
1903 * @get_trigger_ops: The callback function invoked to retrieve the
1904 * event_trigger_ops implementation associated with the command.
1905 * This callback function allows a single event_command to
1906 * support multiple trigger implementations via different sets of
1907 * event_trigger_ops, depending on the value of the @param
1908 * string.
1909 */
1910 struct event_command {
1911 struct list_head list;
1912 char *name;
1913 enum event_trigger_type trigger_type;
1914 int flags;
1915 int (*parse)(struct event_command *cmd_ops,
1916 struct trace_event_file *file,
1917 char *glob, char *cmd,
1918 char *param_and_filter);
1919 int (*reg)(char *glob,
1920 struct event_trigger_data *data,
1921 struct trace_event_file *file);
1922 void (*unreg)(char *glob,
1923 struct event_trigger_data *data,
1924 struct trace_event_file *file);
1925 void (*unreg_all)(struct trace_event_file *file);
1926 int (*set_filter)(char *filter_str,
1927 struct event_trigger_data *data,
1928 struct trace_event_file *file);
1929 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1930 };
1931
1932 /**
1933 * enum event_command_flags - flags for struct event_command
1934 *
1935 * @POST_TRIGGER: A flag that says whether or not this command needs
1936 * to have its action delayed until after the current event has
1937 * been closed. Some triggers need to avoid being invoked while
1938 * an event is currently in the process of being logged, since
1939 * the trigger may itself log data into the trace buffer. Thus
1940 * we make sure the current event is committed before invoking
1941 * those triggers. To do that, the trigger invocation is split
1942 * in two - the first part checks the filter using the current
1943 * trace record; if a command has the @post_trigger flag set, it
1944 * sets a bit for itself in the return value, otherwise it
1945 * directly invokes the trigger. Once all commands have been
1946 * either invoked or set their return flag, the current record is
1947 * either committed or discarded. At that point, if any commands
1948 * have deferred their triggers, those commands are finally
1949 * invoked following the close of the current event. In other
1950 * words, if the event_trigger_ops @func() probe implementation
1951 * itself logs to the trace buffer, this flag should be set,
1952 * otherwise it can be left unspecified.
1953 *
1954 * @NEEDS_REC: A flag that says whether or not this command needs
1955 * access to the trace record in order to perform its function,
1956 * regardless of whether or not it has a filter associated with
1957 * it (filters make a trigger require access to the trace record
1958 * but are not always present).
1959 */
1960 enum event_command_flags {
1961 EVENT_CMD_FL_POST_TRIGGER = 1,
1962 EVENT_CMD_FL_NEEDS_REC = 2,
1963 };
1964
1965 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1966 {
1967 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1968 }
1969
1970 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1971 {
1972 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1973 }
1974
1975 extern int trace_event_enable_disable(struct trace_event_file *file,
1976 int enable, int soft_disable);
1977 extern int tracing_alloc_snapshot(void);
1978 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1979 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1980
1981 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1982 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1983
1984 extern const char *__start___trace_bprintk_fmt[];
1985 extern const char *__stop___trace_bprintk_fmt[];
1986
1987 extern const char *__start___tracepoint_str[];
1988 extern const char *__stop___tracepoint_str[];
1989
1990 void trace_printk_control(bool enabled);
1991 void trace_printk_start_comm(void);
1992 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1993 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1994
1995 /* Used from boot time tracer */
1996 extern int trace_set_options(struct trace_array *tr, char *option);
1997 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1998 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1999 unsigned long size, int cpu_id);
2000 extern int tracing_set_cpumask(struct trace_array *tr,
2001 cpumask_var_t tracing_cpumask_new);
2002
2003
2004 #define MAX_EVENT_NAME_LEN 64
2005
2006 extern ssize_t trace_parse_run_command(struct file *file,
2007 const char __user *buffer, size_t count, loff_t *ppos,
2008 int (*createfn)(const char *));
2009
2010 extern unsigned int err_pos(char *cmd, const char *str);
2011 extern void tracing_log_err(struct trace_array *tr,
2012 const char *loc, const char *cmd,
2013 const char **errs, u8 type, u16 pos);
2014
2015 /*
2016 * Normal trace_printk() and friends allocates special buffers
2017 * to do the manipulation, as well as saves the print formats
2018 * into sections to display. But the trace infrastructure wants
2019 * to use these without the added overhead at the price of being
2020 * a bit slower (used mainly for warnings, where we don't care
2021 * about performance). The internal_trace_puts() is for such
2022 * a purpose.
2023 */
2024 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
2025
2026 #undef FTRACE_ENTRY
2027 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print) \
2028 extern struct trace_event_call \
2029 __aligned(4) event_##call;
2030 #undef FTRACE_ENTRY_DUP
2031 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \
2032 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2033 #undef FTRACE_ENTRY_PACKED
2034 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
2035 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2036
2037 #include "trace_entries.h"
2038
2039 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
2040 int perf_ftrace_event_register(struct trace_event_call *call,
2041 enum trace_reg type, void *data);
2042 #else
2043 #define perf_ftrace_event_register NULL
2044 #endif
2045
2046 #ifdef CONFIG_FTRACE_SYSCALLS
2047 void init_ftrace_syscalls(void);
2048 const char *get_syscall_name(int syscall);
2049 #else
2050 static inline void init_ftrace_syscalls(void) { }
2051 static inline const char *get_syscall_name(int syscall)
2052 {
2053 return NULL;
2054 }
2055 #endif
2056
2057 #ifdef CONFIG_EVENT_TRACING
2058 void trace_event_init(void);
2059 void trace_event_eval_update(struct trace_eval_map **map, int len);
2060 /* Used from boot time tracer */
2061 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
2062 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
2063 #else
2064 static inline void __init trace_event_init(void) { }
2065 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
2066 #endif
2067
2068 #ifdef CONFIG_TRACER_SNAPSHOT
2069 void tracing_snapshot_instance(struct trace_array *tr);
2070 int tracing_alloc_snapshot_instance(struct trace_array *tr);
2071 int tracing_arm_snapshot(struct trace_array *tr);
2072 void tracing_disarm_snapshot(struct trace_array *tr);
2073 #else
2074 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
2075 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
2076 {
2077 return 0;
2078 }
2079 static inline int tracing_arm_snapshot(struct trace_array *tr) { return 0; }
2080 static inline void tracing_disarm_snapshot(struct trace_array *tr) { }
2081 #endif
2082
2083 #ifdef CONFIG_PREEMPT_TRACER
2084 void tracer_preempt_on(unsigned long a0, unsigned long a1);
2085 void tracer_preempt_off(unsigned long a0, unsigned long a1);
2086 #else
2087 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
2088 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2089 #endif
2090 #ifdef CONFIG_IRQSOFF_TRACER
2091 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2092 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2093 #else
2094 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
2095 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2096 #endif
2097
2098 /*
2099 * Reset the state of the trace_iterator so that it can read consumed data.
2100 * Normally, the trace_iterator is used for reading the data when it is not
2101 * consumed, and must retain state.
2102 */
2103 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2104 {
2105 memset_startat(iter, 0, seq);
2106 iter->pos = -1;
2107 }
2108
2109 /* Check the name is good for event/group/fields */
2110 static inline bool __is_good_name(const char *name, bool hash_ok)
2111 {
2112 if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
2113 return false;
2114 while (*++name != '\0') {
2115 if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
2116 (!hash_ok || *name != '-'))
2117 return false;
2118 }
2119 return true;
2120 }
2121
2122 /* Check the name is good for event/group/fields */
2123 static inline bool is_good_name(const char *name)
2124 {
2125 return __is_good_name(name, false);
2126 }
2127
2128 /* Check the name is good for system */
2129 static inline bool is_good_system_name(const char *name)
2130 {
2131 return __is_good_name(name, true);
2132 }
2133
2134 /* Convert certain expected symbols into '_' when generating event names */
2135 static inline void sanitize_event_name(char *name)
2136 {
2137 while (*name++ != '\0')
2138 if (*name == ':' || *name == '.')
2139 *name = '_';
2140 }
2141
2142 /*
2143 * This is a generic way to read and write a u64 value from a file in tracefs.
2144 *
2145 * The value is stored on the variable pointed by *val. The value needs
2146 * to be at least *min and at most *max. The write is protected by an
2147 * existing *lock.
2148 */
2149 struct trace_min_max_param {
2150 struct mutex *lock;
2151 u64 *val;
2152 u64 *min;
2153 u64 *max;
2154 };
2155
2156 #define U64_STR_SIZE 24 /* 20 digits max */
2157
2158 extern const struct file_operations trace_min_max_fops;
2159
2160 #ifdef CONFIG_RV
2161 extern int rv_init_interface(void);
2162 #else
2163 static inline int rv_init_interface(void)
2164 {
2165 return 0;
2166 }
2167 #endif
2168
2169 #endif /* _LINUX_KERNEL_TRACE_H */
2170
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