projects/linux·blob v5.16 · refs

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