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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/*
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 */
136struct syscall_trace_enter {
137 struct trace_entry ent;
138 int nr;
139 unsigned long args[];
140};
141
142struct syscall_trace_exit {
143 struct trace_entry ent;
144 int nr;
145 long ret;
146};
147
148struct kprobe_trace_entry_head {
149 struct trace_entry ent;
150 unsigned long ip;
151};
152
153struct eprobe_trace_entry_head {
154 struct trace_entry ent;
155};
156
157struct kretprobe_trace_entry_head {
158 struct trace_entry ent;
159 unsigned long func;
160 unsigned long ret_ip;
161};
162
163struct fentry_trace_entry_head {
164 struct trace_entry ent;
165 unsigned long ip;
166};
167
168struct 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
176struct 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 */
183struct 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
207struct tracer;
208struct trace_option_dentry;
209
210struct 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
220struct trace_options {
221 struct tracer *tracer;
222 struct trace_option_dentry *topts;
223};
224
225struct trace_pid_list *trace_pid_list_alloc(void);
226void trace_pid_list_free(struct trace_pid_list *pid_list);
227bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
228int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
229int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
230int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
231int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
232 unsigned int *next);
233
234enum {
235 TRACE_PIDS = BIT(0),
236 TRACE_NO_PIDS = BIT(1),
237};
238
239static 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
247static 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
258typedef 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 */
298struct 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 */
307struct 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 */
319struct 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#endif
338#ifdef CONFIG_TRACER_MAX_TRACE
339 unsigned long max_latency;
340#ifdef CONFIG_FSNOTIFY
341 struct dentry *d_max_latency;
342 struct work_struct fsnotify_work;
343 struct irq_work fsnotify_irqwork;
344#endif
345#endif
346 struct trace_pid_list __rcu *filtered_pids;
347 struct trace_pid_list __rcu *filtered_no_pids;
348 /*
349 * max_lock is used to protect the swapping of buffers
350 * when taking a max snapshot. The buffers themselves are
351 * protected by per_cpu spinlocks. But the action of the swap
352 * needs its own lock.
353 *
354 * This is defined as a arch_spinlock_t in order to help
355 * with performance when lockdep debugging is enabled.
356 *
357 * It is also used in other places outside the update_max_tr
358 * so it needs to be defined outside of the
359 * CONFIG_TRACER_MAX_TRACE.
360 */
361 arch_spinlock_t max_lock;
362 int buffer_disabled;
363#ifdef CONFIG_FTRACE_SYSCALLS
364 int sys_refcount_enter;
365 int sys_refcount_exit;
366 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
367 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
368#endif
369 int stop_count;
370 int clock_id;
371 int nr_topts;
372 bool clear_trace;
373 int buffer_percent;
374 unsigned int n_err_log_entries;
375 struct tracer *current_trace;
376 unsigned int trace_flags;
377 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
378 unsigned int flags;
379 raw_spinlock_t start_lock;
380 const char *system_names;
381 struct list_head err_log;
382 struct dentry *dir;
383 struct dentry *options;
384 struct dentry *percpu_dir;
385 struct eventfs_inode *event_dir;
386 struct trace_options *topts;
387 struct list_head systems;
388 struct list_head events;
389 struct trace_event_file *trace_marker_file;
390 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
391 /* one per_cpu trace_pipe can be opened by only one user */
392 cpumask_var_t pipe_cpumask;
393 int ref;
394 int trace_ref;
395#ifdef CONFIG_FUNCTION_TRACER
396 struct ftrace_ops *ops;
397 struct trace_pid_list __rcu *function_pids;
398 struct trace_pid_list __rcu *function_no_pids;
399#ifdef CONFIG_DYNAMIC_FTRACE
400 /* All of these are protected by the ftrace_lock */
401 struct list_head func_probes;
402 struct list_head mod_trace;
403 struct list_head mod_notrace;
404#endif
405 /* function tracing enabled */
406 int function_enabled;
407#endif
408 int no_filter_buffering_ref;
409 struct list_head hist_vars;
410#ifdef CONFIG_TRACER_SNAPSHOT
411 struct cond_snapshot *cond_snapshot;
412#endif
413 struct trace_func_repeats __percpu *last_func_repeats;
414 /*
415 * On boot up, the ring buffer is set to the minimum size, so that
416 * we do not waste memory on systems that are not using tracing.
417 */
418 bool ring_buffer_expanded;
419};
420
421enum {
422 TRACE_ARRAY_FL_GLOBAL = (1 << 0)
423};
424
425extern struct list_head ftrace_trace_arrays;
426
427extern struct mutex trace_types_lock;
428
429extern int trace_array_get(struct trace_array *tr);
430extern int tracing_check_open_get_tr(struct trace_array *tr);
431extern struct trace_array *trace_array_find(const char *instance);
432extern struct trace_array *trace_array_find_get(const char *instance);
433
434extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
435extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
436extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
437
438extern bool trace_clock_in_ns(struct trace_array *tr);
439
440/*
441 * The global tracer (top) should be the first trace array added,
442 * but we check the flag anyway.
443 */
444static inline struct trace_array *top_trace_array(void)
445{
446 struct trace_array *tr;
447
448 if (list_empty(&ftrace_trace_arrays))
449 return NULL;
450
451 tr = list_entry(ftrace_trace_arrays.prev,
452 typeof(*tr), list);
453 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
454 return tr;
455}
456
457#define FTRACE_CMP_TYPE(var, type) \
458 __builtin_types_compatible_p(typeof(var), type *)
459
460#undef IF_ASSIGN
461#define IF_ASSIGN(var, entry, etype, id) \
462 if (FTRACE_CMP_TYPE(var, etype)) { \
463 var = (typeof(var))(entry); \
464 WARN_ON(id != 0 && (entry)->type != id); \
465 break; \
466 }
467
468/* Will cause compile errors if type is not found. */
469extern void __ftrace_bad_type(void);
470
471/*
472 * The trace_assign_type is a verifier that the entry type is
473 * the same as the type being assigned. To add new types simply
474 * add a line with the following format:
475 *
476 * IF_ASSIGN(var, ent, type, id);
477 *
478 * Where "type" is the trace type that includes the trace_entry
479 * as the "ent" item. And "id" is the trace identifier that is
480 * used in the trace_type enum.
481 *
482 * If the type can have more than one id, then use zero.
483 */
484#define trace_assign_type(var, ent) \
485 do { \
486 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
487 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
488 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
489 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
490 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
491 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
492 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
493 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
494 IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
495 IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
496 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
497 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
498 TRACE_MMIO_RW); \
499 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
500 TRACE_MMIO_MAP); \
501 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
502 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
503 TRACE_GRAPH_ENT); \
504 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
505 TRACE_GRAPH_RET); \
506 IF_ASSIGN(var, ent, struct func_repeats_entry, \
507 TRACE_FUNC_REPEATS); \
508 __ftrace_bad_type(); \
509 } while (0)
510
511/*
512 * An option specific to a tracer. This is a boolean value.
513 * The bit is the bit index that sets its value on the
514 * flags value in struct tracer_flags.
515 */
516struct tracer_opt {
517 const char *name; /* Will appear on the trace_options file */
518 u32 bit; /* Mask assigned in val field in tracer_flags */
519};
520
521/*
522 * The set of specific options for a tracer. Your tracer
523 * have to set the initial value of the flags val.
524 */
525struct tracer_flags {
526 u32 val;
527 struct tracer_opt *opts;
528 struct tracer *trace;
529};
530
531/* Makes more easy to define a tracer opt */
532#define TRACER_OPT(s, b) .name = #s, .bit = b
533
534
535struct trace_option_dentry {
536 struct tracer_opt *opt;
537 struct tracer_flags *flags;
538 struct trace_array *tr;
539 struct dentry *entry;
540};
541
542/**
543 * struct tracer - a specific tracer and its callbacks to interact with tracefs
544 * @name: the name chosen to select it on the available_tracers file
545 * @init: called when one switches to this tracer (echo name > current_tracer)
546 * @reset: called when one switches to another tracer
547 * @start: called when tracing is unpaused (echo 1 > tracing_on)
548 * @stop: called when tracing is paused (echo 0 > tracing_on)
549 * @update_thresh: called when tracing_thresh is updated
550 * @open: called when the trace file is opened
551 * @pipe_open: called when the trace_pipe file is opened
552 * @close: called when the trace file is released
553 * @pipe_close: called when the trace_pipe file is released
554 * @read: override the default read callback on trace_pipe
555 * @splice_read: override the default splice_read callback on trace_pipe
556 * @selftest: selftest to run on boot (see trace_selftest.c)
557 * @print_headers: override the first lines that describe your columns
558 * @print_line: callback that prints a trace
559 * @set_flag: signals one of your private flags changed (trace_options file)
560 * @flags: your private flags
561 */
562struct tracer {
563 const char *name;
564 int (*init)(struct trace_array *tr);
565 void (*reset)(struct trace_array *tr);
566 void (*start)(struct trace_array *tr);
567 void (*stop)(struct trace_array *tr);
568 int (*update_thresh)(struct trace_array *tr);
569 void (*open)(struct trace_iterator *iter);
570 void (*pipe_open)(struct trace_iterator *iter);
571 void (*close)(struct trace_iterator *iter);
572 void (*pipe_close)(struct trace_iterator *iter);
573 ssize_t (*read)(struct trace_iterator *iter,
574 struct file *filp, char __user *ubuf,
575 size_t cnt, loff_t *ppos);
576 ssize_t (*splice_read)(struct trace_iterator *iter,
577 struct file *filp,
578 loff_t *ppos,
579 struct pipe_inode_info *pipe,
580 size_t len,
581 unsigned int flags);
582#ifdef CONFIG_FTRACE_STARTUP_TEST
583 int (*selftest)(struct tracer *trace,
584 struct trace_array *tr);
585#endif
586 void (*print_header)(struct seq_file *m);
587 enum print_line_t (*print_line)(struct trace_iterator *iter);
588 /* If you handled the flag setting, return 0 */
589 int (*set_flag)(struct trace_array *tr,
590 u32 old_flags, u32 bit, int set);
591 /* Return 0 if OK with change, else return non-zero */
592 int (*flag_changed)(struct trace_array *tr,
593 u32 mask, int set);
594 struct tracer *next;
595 struct tracer_flags *flags;
596 int enabled;
597 bool print_max;
598 bool allow_instances;
599#ifdef CONFIG_TRACER_MAX_TRACE
600 bool use_max_tr;
601#endif
602 /* True if tracer cannot be enabled in kernel param */
603 bool noboot;
604};
605
606static inline struct ring_buffer_iter *
607trace_buffer_iter(struct trace_iterator *iter, int cpu)
608{
609 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
610}
611
612int tracer_init(struct tracer *t, struct trace_array *tr);
613int tracing_is_enabled(void);
614void tracing_reset_online_cpus(struct array_buffer *buf);
615void tracing_reset_all_online_cpus(void);
616void tracing_reset_all_online_cpus_unlocked(void);
617int tracing_open_generic(struct inode *inode, struct file *filp);
618int tracing_open_generic_tr(struct inode *inode, struct file *filp);
619int tracing_release_generic_tr(struct inode *inode, struct file *file);
620int tracing_open_file_tr(struct inode *inode, struct file *filp);
621int tracing_release_file_tr(struct inode *inode, struct file *filp);
622int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
623bool tracing_is_disabled(void);
624bool tracer_tracing_is_on(struct trace_array *tr);
625void tracer_tracing_on(struct trace_array *tr);
626void tracer_tracing_off(struct trace_array *tr);
627struct dentry *trace_create_file(const char *name,
628 umode_t mode,
629 struct dentry *parent,
630 void *data,
631 const struct file_operations *fops);
632
633int tracing_init_dentry(void);
634
635struct ring_buffer_event;
636
637struct ring_buffer_event *
638trace_buffer_lock_reserve(struct trace_buffer *buffer,
639 int type,
640 unsigned long len,
641 unsigned int trace_ctx);
642
643struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
644 struct trace_array_cpu *data);
645
646struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
647 int *ent_cpu, u64 *ent_ts);
648
649void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
650 struct ring_buffer_event *event);
651
652bool trace_is_tracepoint_string(const char *str);
653const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
654void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
655 va_list ap) __printf(2, 0);
656char *trace_iter_expand_format(struct trace_iterator *iter);
657
658int trace_empty(struct trace_iterator *iter);
659
660void *trace_find_next_entry_inc(struct trace_iterator *iter);
661
662void trace_init_global_iter(struct trace_iterator *iter);
663
664void tracing_iter_reset(struct trace_iterator *iter, int cpu);
665
666unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
667unsigned long trace_total_entries(struct trace_array *tr);
668
669void trace_function(struct trace_array *tr,
670 unsigned long ip,
671 unsigned long parent_ip,
672 unsigned int trace_ctx);
673void trace_graph_function(struct trace_array *tr,
674 unsigned long ip,
675 unsigned long parent_ip,
676 unsigned int trace_ctx);
677void trace_latency_header(struct seq_file *m);
678void trace_default_header(struct seq_file *m);
679void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
680
681void trace_graph_return(struct ftrace_graph_ret *trace);
682int trace_graph_entry(struct ftrace_graph_ent *trace);
683void set_graph_array(struct trace_array *tr);
684
685void tracing_start_cmdline_record(void);
686void tracing_stop_cmdline_record(void);
687void tracing_start_tgid_record(void);
688void tracing_stop_tgid_record(void);
689
690int register_tracer(struct tracer *type);
691int is_tracing_stopped(void);
692
693loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
694
695extern cpumask_var_t __read_mostly tracing_buffer_mask;
696
697#define for_each_tracing_cpu(cpu) \
698 for_each_cpu(cpu, tracing_buffer_mask)
699
700extern unsigned long nsecs_to_usecs(unsigned long nsecs);
701
702extern unsigned long tracing_thresh;
703
704/* PID filtering */
705
706extern int pid_max;
707
708bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
709 pid_t search_pid);
710bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
711 struct trace_pid_list *filtered_no_pids,
712 struct task_struct *task);
713void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
714 struct task_struct *self,
715 struct task_struct *task);
716void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
717void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
718int trace_pid_show(struct seq_file *m, void *v);
719int trace_pid_write(struct trace_pid_list *filtered_pids,
720 struct trace_pid_list **new_pid_list,
721 const char __user *ubuf, size_t cnt);
722
723#ifdef CONFIG_TRACER_MAX_TRACE
724void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
725 void *cond_data);
726void update_max_tr_single(struct trace_array *tr,
727 struct task_struct *tsk, int cpu);
728
729#ifdef CONFIG_FSNOTIFY
730#define LATENCY_FS_NOTIFY
731#endif
732#endif /* CONFIG_TRACER_MAX_TRACE */
733
734#ifdef LATENCY_FS_NOTIFY
735void latency_fsnotify(struct trace_array *tr);
736#else
737static inline void latency_fsnotify(struct trace_array *tr) { }
738#endif
739
740#ifdef CONFIG_STACKTRACE
741void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
742#else
743static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
744 int skip)
745{
746}
747#endif /* CONFIG_STACKTRACE */
748
749void trace_last_func_repeats(struct trace_array *tr,
750 struct trace_func_repeats *last_info,
751 unsigned int trace_ctx);
752
753extern u64 ftrace_now(int cpu);
754
755extern void trace_find_cmdline(int pid, char comm[]);
756extern int trace_find_tgid(int pid);
757extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
758
759#ifdef CONFIG_DYNAMIC_FTRACE
760extern unsigned long ftrace_update_tot_cnt;
761extern unsigned long ftrace_number_of_pages;
762extern unsigned long ftrace_number_of_groups;
763void ftrace_init_trace_array(struct trace_array *tr);
764#else
765static inline void ftrace_init_trace_array(struct trace_array *tr) { }
766#endif
767#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
768extern int DYN_FTRACE_TEST_NAME(void);
769#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
770extern int DYN_FTRACE_TEST_NAME2(void);
771
772extern void trace_set_ring_buffer_expanded(struct trace_array *tr);
773extern bool tracing_selftest_disabled;
774
775#ifdef CONFIG_FTRACE_STARTUP_TEST
776extern void __init disable_tracing_selftest(const char *reason);
777
778extern int trace_selftest_startup_function(struct tracer *trace,
779 struct trace_array *tr);
780extern int trace_selftest_startup_function_graph(struct tracer *trace,
781 struct trace_array *tr);
782extern int trace_selftest_startup_irqsoff(struct tracer *trace,
783 struct trace_array *tr);
784extern int trace_selftest_startup_preemptoff(struct tracer *trace,
785 struct trace_array *tr);
786extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
787 struct trace_array *tr);
788extern int trace_selftest_startup_wakeup(struct tracer *trace,
789 struct trace_array *tr);
790extern int trace_selftest_startup_nop(struct tracer *trace,
791 struct trace_array *tr);
792extern int trace_selftest_startup_branch(struct tracer *trace,
793 struct trace_array *tr);
794/*
795 * Tracer data references selftest functions that only occur
796 * on boot up. These can be __init functions. Thus, when selftests
797 * are enabled, then the tracers need to reference __init functions.
798 */
799#define __tracer_data __refdata
800#else
801static inline void __init disable_tracing_selftest(const char *reason)
802{
803}
804/* Tracers are seldom changed. Optimize when selftests are disabled. */
805#define __tracer_data __read_mostly
806#endif /* CONFIG_FTRACE_STARTUP_TEST */
807
808extern void *head_page(struct trace_array_cpu *data);
809extern unsigned long long ns2usecs(u64 nsec);
810extern int
811trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
812extern int
813trace_vprintk(unsigned long ip, const char *fmt, va_list args);
814extern int
815trace_array_vprintk(struct trace_array *tr,
816 unsigned long ip, const char *fmt, va_list args);
817int trace_array_printk_buf(struct trace_buffer *buffer,
818 unsigned long ip, const char *fmt, ...);
819void trace_printk_seq(struct trace_seq *s);
820enum print_line_t print_trace_line(struct trace_iterator *iter);
821
822extern char trace_find_mark(unsigned long long duration);
823
824struct ftrace_hash;
825
826struct ftrace_mod_load {
827 struct list_head list;
828 char *func;
829 char *module;
830 int enable;
831};
832
833enum {
834 FTRACE_HASH_FL_MOD = (1 << 0),
835};
836
837struct ftrace_hash {
838 unsigned long size_bits;
839 struct hlist_head *buckets;
840 unsigned long count;
841 unsigned long flags;
842 struct rcu_head rcu;
843};
844
845struct ftrace_func_entry *
846ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
847
848static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
849{
850 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
851}
852
853/* Standard output formatting function used for function return traces */
854#ifdef CONFIG_FUNCTION_GRAPH_TRACER
855
856/* Flag options */
857#define TRACE_GRAPH_PRINT_OVERRUN 0x1
858#define TRACE_GRAPH_PRINT_CPU 0x2
859#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
860#define TRACE_GRAPH_PRINT_PROC 0x8
861#define TRACE_GRAPH_PRINT_DURATION 0x10
862#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
863#define TRACE_GRAPH_PRINT_REL_TIME 0x40
864#define TRACE_GRAPH_PRINT_IRQS 0x80
865#define TRACE_GRAPH_PRINT_TAIL 0x100
866#define TRACE_GRAPH_SLEEP_TIME 0x200
867#define TRACE_GRAPH_GRAPH_TIME 0x400
868#define TRACE_GRAPH_PRINT_RETVAL 0x800
869#define TRACE_GRAPH_PRINT_RETVAL_HEX 0x1000
870#define TRACE_GRAPH_PRINT_FILL_SHIFT 28
871#define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
872
873extern void ftrace_graph_sleep_time_control(bool enable);
874
875#ifdef CONFIG_FUNCTION_PROFILER
876extern void ftrace_graph_graph_time_control(bool enable);
877#else
878static inline void ftrace_graph_graph_time_control(bool enable) { }
879#endif
880
881extern enum print_line_t
882print_graph_function_flags(struct trace_iterator *iter, u32 flags);
883extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
884extern void
885trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
886extern void graph_trace_open(struct trace_iterator *iter);
887extern void graph_trace_close(struct trace_iterator *iter);
888extern int __trace_graph_entry(struct trace_array *tr,
889 struct ftrace_graph_ent *trace,
890 unsigned int trace_ctx);
891extern void __trace_graph_return(struct trace_array *tr,
892 struct ftrace_graph_ret *trace,
893 unsigned int trace_ctx);
894
895#ifdef CONFIG_DYNAMIC_FTRACE
896extern struct ftrace_hash __rcu *ftrace_graph_hash;
897extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
898
899static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
900{
901 unsigned long addr = trace->func;
902 int ret = 0;
903 struct ftrace_hash *hash;
904
905 preempt_disable_notrace();
906
907 /*
908 * Have to open code "rcu_dereference_sched()" because the
909 * function graph tracer can be called when RCU is not
910 * "watching".
911 * Protected with schedule_on_each_cpu(ftrace_sync)
912 */
913 hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
914
915 if (ftrace_hash_empty(hash)) {
916 ret = 1;
917 goto out;
918 }
919
920 if (ftrace_lookup_ip(hash, addr)) {
921
922 /*
923 * This needs to be cleared on the return functions
924 * when the depth is zero.
925 */
926 trace_recursion_set(TRACE_GRAPH_BIT);
927 trace_recursion_set_depth(trace->depth);
928
929 /*
930 * If no irqs are to be traced, but a set_graph_function
931 * is set, and called by an interrupt handler, we still
932 * want to trace it.
933 */
934 if (in_hardirq())
935 trace_recursion_set(TRACE_IRQ_BIT);
936 else
937 trace_recursion_clear(TRACE_IRQ_BIT);
938 ret = 1;
939 }
940
941out:
942 preempt_enable_notrace();
943 return ret;
944}
945
946static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
947{
948 if (trace_recursion_test(TRACE_GRAPH_BIT) &&
949 trace->depth == trace_recursion_depth())
950 trace_recursion_clear(TRACE_GRAPH_BIT);
951}
952
953static inline int ftrace_graph_notrace_addr(unsigned long addr)
954{
955 int ret = 0;
956 struct ftrace_hash *notrace_hash;
957
958 preempt_disable_notrace();
959
960 /*
961 * Have to open code "rcu_dereference_sched()" because the
962 * function graph tracer can be called when RCU is not
963 * "watching".
964 * Protected with schedule_on_each_cpu(ftrace_sync)
965 */
966 notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
967 !preemptible());
968
969 if (ftrace_lookup_ip(notrace_hash, addr))
970 ret = 1;
971
972 preempt_enable_notrace();
973 return ret;
974}
975#else
976static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
977{
978 return 1;
979}
980
981static inline int ftrace_graph_notrace_addr(unsigned long addr)
982{
983 return 0;
984}
985static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
986{ }
987#endif /* CONFIG_DYNAMIC_FTRACE */
988
989extern unsigned int fgraph_max_depth;
990
991static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
992{
993 /* trace it when it is-nested-in or is a function enabled. */
994 return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
995 ftrace_graph_addr(trace)) ||
996 (trace->depth < 0) ||
997 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
998}
999
1000#else /* CONFIG_FUNCTION_GRAPH_TRACER */
1001static inline enum print_line_t
1002print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1003{
1004 return TRACE_TYPE_UNHANDLED;
1005}
1006#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1007
1008extern struct list_head ftrace_pids;
1009
1010#ifdef CONFIG_FUNCTION_TRACER
1011
1012#define FTRACE_PID_IGNORE -1
1013#define FTRACE_PID_TRACE -2
1014
1015struct ftrace_func_command {
1016 struct list_head list;
1017 char *name;
1018 int (*func)(struct trace_array *tr,
1019 struct ftrace_hash *hash,
1020 char *func, char *cmd,
1021 char *params, int enable);
1022};
1023extern bool ftrace_filter_param __initdata;
1024static inline int ftrace_trace_task(struct trace_array *tr)
1025{
1026 return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1027 FTRACE_PID_IGNORE;
1028}
1029extern int ftrace_is_dead(void);
1030int ftrace_create_function_files(struct trace_array *tr,
1031 struct dentry *parent);
1032void ftrace_destroy_function_files(struct trace_array *tr);
1033int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1034void ftrace_free_ftrace_ops(struct trace_array *tr);
1035void ftrace_init_global_array_ops(struct trace_array *tr);
1036void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1037void ftrace_reset_array_ops(struct trace_array *tr);
1038void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1039void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1040 struct dentry *d_tracer);
1041void ftrace_clear_pids(struct trace_array *tr);
1042int init_function_trace(void);
1043void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1044#else
1045static inline int ftrace_trace_task(struct trace_array *tr)
1046{
1047 return 1;
1048}
1049static inline int ftrace_is_dead(void) { return 0; }
1050static inline int
1051ftrace_create_function_files(struct trace_array *tr,
1052 struct dentry *parent)
1053{
1054 return 0;
1055}
1056static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1057{
1058 return 0;
1059}
1060static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
1061static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1062static inline __init void
1063ftrace_init_global_array_ops(struct trace_array *tr) { }
1064static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1065static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1066static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1067static inline void ftrace_clear_pids(struct trace_array *tr) { }
1068static inline int init_function_trace(void) { return 0; }
1069static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1070/* ftace_func_t type is not defined, use macro instead of static inline */
1071#define ftrace_init_array_ops(tr, func) do { } while (0)
1072#endif /* CONFIG_FUNCTION_TRACER */
1073
1074#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1075
1076struct ftrace_probe_ops {
1077 void (*func)(unsigned long ip,
1078 unsigned long parent_ip,
1079 struct trace_array *tr,
1080 struct ftrace_probe_ops *ops,
1081 void *data);
1082 int (*init)(struct ftrace_probe_ops *ops,
1083 struct trace_array *tr,
1084 unsigned long ip, void *init_data,
1085 void **data);
1086 void (*free)(struct ftrace_probe_ops *ops,
1087 struct trace_array *tr,
1088 unsigned long ip, void *data);
1089 int (*print)(struct seq_file *m,
1090 unsigned long ip,
1091 struct ftrace_probe_ops *ops,
1092 void *data);
1093};
1094
1095struct ftrace_func_mapper;
1096typedef int (*ftrace_mapper_func)(void *data);
1097
1098struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1099void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1100 unsigned long ip);
1101int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1102 unsigned long ip, void *data);
1103void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1104 unsigned long ip);
1105void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1106 ftrace_mapper_func free_func);
1107
1108extern int
1109register_ftrace_function_probe(char *glob, struct trace_array *tr,
1110 struct ftrace_probe_ops *ops, void *data);
1111extern int
1112unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1113 struct ftrace_probe_ops *ops);
1114extern void clear_ftrace_function_probes(struct trace_array *tr);
1115
1116int register_ftrace_command(struct ftrace_func_command *cmd);
1117int unregister_ftrace_command(struct ftrace_func_command *cmd);
1118
1119void ftrace_create_filter_files(struct ftrace_ops *ops,
1120 struct dentry *parent);
1121void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1122
1123extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1124 int len, int reset);
1125extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1126 int len, int reset);
1127#else
1128struct ftrace_func_command;
1129
1130static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1131{
1132 return -EINVAL;
1133}
1134static inline __init int unregister_ftrace_command(char *cmd_name)
1135{
1136 return -EINVAL;
1137}
1138static inline void clear_ftrace_function_probes(struct trace_array *tr)
1139{
1140}
1141
1142/*
1143 * The ops parameter passed in is usually undefined.
1144 * This must be a macro.
1145 */
1146#define ftrace_create_filter_files(ops, parent) do { } while (0)
1147#define ftrace_destroy_filter_files(ops) do { } while (0)
1148#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1149
1150bool ftrace_event_is_function(struct trace_event_call *call);
1151
1152/*
1153 * struct trace_parser - servers for reading the user input separated by spaces
1154 * @cont: set if the input is not complete - no final space char was found
1155 * @buffer: holds the parsed user input
1156 * @idx: user input length
1157 * @size: buffer size
1158 */
1159struct trace_parser {
1160 bool cont;
1161 char *buffer;
1162 unsigned idx;
1163 unsigned size;
1164};
1165
1166static inline bool trace_parser_loaded(struct trace_parser *parser)
1167{
1168 return (parser->idx != 0);
1169}
1170
1171static inline bool trace_parser_cont(struct trace_parser *parser)
1172{
1173 return parser->cont;
1174}
1175
1176static inline void trace_parser_clear(struct trace_parser *parser)
1177{
1178 parser->cont = false;
1179 parser->idx = 0;
1180}
1181
1182extern int trace_parser_get_init(struct trace_parser *parser, int size);
1183extern void trace_parser_put(struct trace_parser *parser);
1184extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1185 size_t cnt, loff_t *ppos);
1186
1187/*
1188 * Only create function graph options if function graph is configured.
1189 */
1190#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1191# define FGRAPH_FLAGS \
1192 C(DISPLAY_GRAPH, "display-graph"),
1193#else
1194# define FGRAPH_FLAGS
1195#endif
1196
1197#ifdef CONFIG_BRANCH_TRACER
1198# define BRANCH_FLAGS \
1199 C(BRANCH, "branch"),
1200#else
1201# define BRANCH_FLAGS
1202#endif
1203
1204#ifdef CONFIG_FUNCTION_TRACER
1205# define FUNCTION_FLAGS \
1206 C(FUNCTION, "function-trace"), \
1207 C(FUNC_FORK, "function-fork"),
1208# define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1209#else
1210# define FUNCTION_FLAGS
1211# define FUNCTION_DEFAULT_FLAGS 0UL
1212# define TRACE_ITER_FUNC_FORK 0UL
1213#endif
1214
1215#ifdef CONFIG_STACKTRACE
1216# define STACK_FLAGS \
1217 C(STACKTRACE, "stacktrace"),
1218#else
1219# define STACK_FLAGS
1220#endif
1221
1222/*
1223 * trace_iterator_flags is an enumeration that defines bit
1224 * positions into trace_flags that controls the output.
1225 *
1226 * NOTE: These bits must match the trace_options array in
1227 * trace.c (this macro guarantees it).
1228 */
1229#define TRACE_FLAGS \
1230 C(PRINT_PARENT, "print-parent"), \
1231 C(SYM_OFFSET, "sym-offset"), \
1232 C(SYM_ADDR, "sym-addr"), \
1233 C(VERBOSE, "verbose"), \
1234 C(RAW, "raw"), \
1235 C(HEX, "hex"), \
1236 C(BIN, "bin"), \
1237 C(BLOCK, "block"), \
1238 C(FIELDS, "fields"), \
1239 C(PRINTK, "trace_printk"), \
1240 C(ANNOTATE, "annotate"), \
1241 C(USERSTACKTRACE, "userstacktrace"), \
1242 C(SYM_USEROBJ, "sym-userobj"), \
1243 C(PRINTK_MSGONLY, "printk-msg-only"), \
1244 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1245 C(LATENCY_FMT, "latency-format"), \
1246 C(RECORD_CMD, "record-cmd"), \
1247 C(RECORD_TGID, "record-tgid"), \
1248 C(OVERWRITE, "overwrite"), \
1249 C(STOP_ON_FREE, "disable_on_free"), \
1250 C(IRQ_INFO, "irq-info"), \
1251 C(MARKERS, "markers"), \
1252 C(EVENT_FORK, "event-fork"), \
1253 C(PAUSE_ON_TRACE, "pause-on-trace"), \
1254 C(HASH_PTR, "hash-ptr"), /* Print hashed pointer */ \
1255 FUNCTION_FLAGS \
1256 FGRAPH_FLAGS \
1257 STACK_FLAGS \
1258 BRANCH_FLAGS
1259
1260/*
1261 * By defining C, we can make TRACE_FLAGS a list of bit names
1262 * that will define the bits for the flag masks.
1263 */
1264#undef C
1265#define C(a, b) TRACE_ITER_##a##_BIT
1266
1267enum trace_iterator_bits {
1268 TRACE_FLAGS
1269 /* Make sure we don't go more than we have bits for */
1270 TRACE_ITER_LAST_BIT
1271};
1272
1273/*
1274 * By redefining C, we can make TRACE_FLAGS a list of masks that
1275 * use the bits as defined above.
1276 */
1277#undef C
1278#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1279
1280enum trace_iterator_flags { TRACE_FLAGS };
1281
1282/*
1283 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1284 * control the output of kernel symbols.
1285 */
1286#define TRACE_ITER_SYM_MASK \
1287 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1288
1289extern struct tracer nop_trace;
1290
1291#ifdef CONFIG_BRANCH_TRACER
1292extern int enable_branch_tracing(struct trace_array *tr);
1293extern void disable_branch_tracing(void);
1294static inline int trace_branch_enable(struct trace_array *tr)
1295{
1296 if (tr->trace_flags & TRACE_ITER_BRANCH)
1297 return enable_branch_tracing(tr);
1298 return 0;
1299}
1300static inline void trace_branch_disable(void)
1301{
1302 /* due to races, always disable */
1303 disable_branch_tracing();
1304}
1305#else
1306static inline int trace_branch_enable(struct trace_array *tr)
1307{
1308 return 0;
1309}
1310static inline void trace_branch_disable(void)
1311{
1312}
1313#endif /* CONFIG_BRANCH_TRACER */
1314
1315/* set ring buffers to default size if not already done so */
1316int tracing_update_buffers(struct trace_array *tr);
1317
1318union trace_synth_field {
1319 u8 as_u8;
1320 u16 as_u16;
1321 u32 as_u32;
1322 u64 as_u64;
1323 struct trace_dynamic_info as_dynamic;
1324};
1325
1326struct ftrace_event_field {
1327 struct list_head link;
1328 const char *name;
1329 const char *type;
1330 int filter_type;
1331 int offset;
1332 int size;
1333 int is_signed;
1334 int len;
1335};
1336
1337struct prog_entry;
1338
1339struct event_filter {
1340 struct prog_entry __rcu *prog;
1341 char *filter_string;
1342};
1343
1344struct event_subsystem {
1345 struct list_head list;
1346 const char *name;
1347 struct event_filter *filter;
1348 int ref_count;
1349};
1350
1351struct trace_subsystem_dir {
1352 struct list_head list;
1353 struct event_subsystem *subsystem;
1354 struct trace_array *tr;
1355 struct eventfs_inode *ei;
1356 int ref_count;
1357 int nr_events;
1358};
1359
1360extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1361 struct trace_buffer *buffer,
1362 struct ring_buffer_event *event);
1363
1364void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1365 struct trace_buffer *buffer,
1366 struct ring_buffer_event *event,
1367 unsigned int trcace_ctx,
1368 struct pt_regs *regs);
1369
1370static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1371 struct trace_buffer *buffer,
1372 struct ring_buffer_event *event,
1373 unsigned int trace_ctx)
1374{
1375 trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1376}
1377
1378DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1379DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1380void trace_buffered_event_disable(void);
1381void trace_buffered_event_enable(void);
1382
1383void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1384
1385static inline void
1386__trace_event_discard_commit(struct trace_buffer *buffer,
1387 struct ring_buffer_event *event)
1388{
1389 if (this_cpu_read(trace_buffered_event) == event) {
1390 /* Simply release the temp buffer and enable preemption */
1391 this_cpu_dec(trace_buffered_event_cnt);
1392 preempt_enable_notrace();
1393 return;
1394 }
1395 /* ring_buffer_discard_commit() enables preemption */
1396 ring_buffer_discard_commit(buffer, event);
1397}
1398
1399/*
1400 * Helper function for event_trigger_unlock_commit{_regs}().
1401 * If there are event triggers attached to this event that requires
1402 * filtering against its fields, then they will be called as the
1403 * entry already holds the field information of the current event.
1404 *
1405 * It also checks if the event should be discarded or not.
1406 * It is to be discarded if the event is soft disabled and the
1407 * event was only recorded to process triggers, or if the event
1408 * filter is active and this event did not match the filters.
1409 *
1410 * Returns true if the event is discarded, false otherwise.
1411 */
1412static inline bool
1413__event_trigger_test_discard(struct trace_event_file *file,
1414 struct trace_buffer *buffer,
1415 struct ring_buffer_event *event,
1416 void *entry,
1417 enum event_trigger_type *tt)
1418{
1419 unsigned long eflags = file->flags;
1420
1421 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1422 *tt = event_triggers_call(file, buffer, entry, event);
1423
1424 if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1425 EVENT_FILE_FL_FILTERED |
1426 EVENT_FILE_FL_PID_FILTER))))
1427 return false;
1428
1429 if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1430 goto discard;
1431
1432 if (file->flags & EVENT_FILE_FL_FILTERED &&
1433 !filter_match_preds(file->filter, entry))
1434 goto discard;
1435
1436 if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1437 trace_event_ignore_this_pid(file))
1438 goto discard;
1439
1440 return false;
1441 discard:
1442 __trace_event_discard_commit(buffer, event);
1443 return true;
1444}
1445
1446/**
1447 * event_trigger_unlock_commit - handle triggers and finish event commit
1448 * @file: The file pointer associated with the event
1449 * @buffer: The ring buffer that the event is being written to
1450 * @event: The event meta data in the ring buffer
1451 * @entry: The event itself
1452 * @trace_ctx: The tracing context flags.
1453 *
1454 * This is a helper function to handle triggers that require data
1455 * from the event itself. It also tests the event against filters and
1456 * if the event is soft disabled and should be discarded.
1457 */
1458static inline void
1459event_trigger_unlock_commit(struct trace_event_file *file,
1460 struct trace_buffer *buffer,
1461 struct ring_buffer_event *event,
1462 void *entry, unsigned int trace_ctx)
1463{
1464 enum event_trigger_type tt = ETT_NONE;
1465
1466 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1467 trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1468
1469 if (tt)
1470 event_triggers_post_call(file, tt);
1471}
1472
1473#define FILTER_PRED_INVALID ((unsigned short)-1)
1474#define FILTER_PRED_IS_RIGHT (1 << 15)
1475#define FILTER_PRED_FOLD (1 << 15)
1476
1477/*
1478 * The max preds is the size of unsigned short with
1479 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1480 * and FOLD flags. The other is reserved.
1481 *
1482 * 2^14 preds is way more than enough.
1483 */
1484#define MAX_FILTER_PRED 16384
1485
1486struct filter_pred;
1487struct regex;
1488
1489typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1490
1491enum regex_type {
1492 MATCH_FULL = 0,
1493 MATCH_FRONT_ONLY,
1494 MATCH_MIDDLE_ONLY,
1495 MATCH_END_ONLY,
1496 MATCH_GLOB,
1497 MATCH_INDEX,
1498};
1499
1500struct regex {
1501 char pattern[MAX_FILTER_STR_VAL];
1502 int len;
1503 int field_len;
1504 regex_match_func match;
1505};
1506
1507static inline bool is_string_field(struct ftrace_event_field *field)
1508{
1509 return field->filter_type == FILTER_DYN_STRING ||
1510 field->filter_type == FILTER_RDYN_STRING ||
1511 field->filter_type == FILTER_STATIC_STRING ||
1512 field->filter_type == FILTER_PTR_STRING ||
1513 field->filter_type == FILTER_COMM;
1514}
1515
1516static inline bool is_function_field(struct ftrace_event_field *field)
1517{
1518 return field->filter_type == FILTER_TRACE_FN;
1519}
1520
1521extern enum regex_type
1522filter_parse_regex(char *buff, int len, char **search, int *not);
1523extern void print_event_filter(struct trace_event_file *file,
1524 struct trace_seq *s);
1525extern int apply_event_filter(struct trace_event_file *file,
1526 char *filter_string);
1527extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1528 char *filter_string);
1529extern void print_subsystem_event_filter(struct event_subsystem *system,
1530 struct trace_seq *s);
1531extern int filter_assign_type(const char *type);
1532extern int create_event_filter(struct trace_array *tr,
1533 struct trace_event_call *call,
1534 char *filter_str, bool set_str,
1535 struct event_filter **filterp);
1536extern void free_event_filter(struct event_filter *filter);
1537
1538struct ftrace_event_field *
1539trace_find_event_field(struct trace_event_call *call, char *name);
1540
1541extern void trace_event_enable_cmd_record(bool enable);
1542extern void trace_event_enable_tgid_record(bool enable);
1543
1544extern int event_trace_init(void);
1545extern int init_events(void);
1546extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1547extern int event_trace_del_tracer(struct trace_array *tr);
1548extern void __trace_early_add_events(struct trace_array *tr);
1549
1550extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1551 const char *system,
1552 const char *event);
1553extern struct trace_event_file *find_event_file(struct trace_array *tr,
1554 const char *system,
1555 const char *event);
1556
1557static inline void *event_file_data(struct file *filp)
1558{
1559 return READ_ONCE(file_inode(filp)->i_private);
1560}
1561
1562extern struct mutex event_mutex;
1563extern struct list_head ftrace_events;
1564
1565extern const struct file_operations event_trigger_fops;
1566extern const struct file_operations event_hist_fops;
1567extern const struct file_operations event_hist_debug_fops;
1568extern const struct file_operations event_inject_fops;
1569
1570#ifdef CONFIG_HIST_TRIGGERS
1571extern int register_trigger_hist_cmd(void);
1572extern int register_trigger_hist_enable_disable_cmds(void);
1573#else
1574static inline int register_trigger_hist_cmd(void) { return 0; }
1575static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1576#endif
1577
1578extern int register_trigger_cmds(void);
1579extern void clear_event_triggers(struct trace_array *tr);
1580
1581enum {
1582 EVENT_TRIGGER_FL_PROBE = BIT(0),
1583};
1584
1585struct event_trigger_data {
1586 unsigned long count;
1587 int ref;
1588 int flags;
1589 struct event_trigger_ops *ops;
1590 struct event_command *cmd_ops;
1591 struct event_filter __rcu *filter;
1592 char *filter_str;
1593 void *private_data;
1594 bool paused;
1595 bool paused_tmp;
1596 struct list_head list;
1597 char *name;
1598 struct list_head named_list;
1599 struct event_trigger_data *named_data;
1600};
1601
1602/* Avoid typos */
1603#define ENABLE_EVENT_STR "enable_event"
1604#define DISABLE_EVENT_STR "disable_event"
1605#define ENABLE_HIST_STR "enable_hist"
1606#define DISABLE_HIST_STR "disable_hist"
1607
1608struct enable_trigger_data {
1609 struct trace_event_file *file;
1610 bool enable;
1611 bool hist;
1612};
1613
1614extern int event_enable_trigger_print(struct seq_file *m,
1615 struct event_trigger_data *data);
1616extern void event_enable_trigger_free(struct event_trigger_data *data);
1617extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1618 struct trace_event_file *file,
1619 char *glob, char *cmd,
1620 char *param_and_filter);
1621extern int event_enable_register_trigger(char *glob,
1622 struct event_trigger_data *data,
1623 struct trace_event_file *file);
1624extern void event_enable_unregister_trigger(char *glob,
1625 struct event_trigger_data *test,
1626 struct trace_event_file *file);
1627extern void trigger_data_free(struct event_trigger_data *data);
1628extern int event_trigger_init(struct event_trigger_data *data);
1629extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1630 int trigger_enable);
1631extern void update_cond_flag(struct trace_event_file *file);
1632extern int set_trigger_filter(char *filter_str,
1633 struct event_trigger_data *trigger_data,
1634 struct trace_event_file *file);
1635extern struct event_trigger_data *find_named_trigger(const char *name);
1636extern bool is_named_trigger(struct event_trigger_data *test);
1637extern int save_named_trigger(const char *name,
1638 struct event_trigger_data *data);
1639extern void del_named_trigger(struct event_trigger_data *data);
1640extern void pause_named_trigger(struct event_trigger_data *data);
1641extern void unpause_named_trigger(struct event_trigger_data *data);
1642extern void set_named_trigger_data(struct event_trigger_data *data,
1643 struct event_trigger_data *named_data);
1644extern struct event_trigger_data *
1645get_named_trigger_data(struct event_trigger_data *data);
1646extern int register_event_command(struct event_command *cmd);
1647extern int unregister_event_command(struct event_command *cmd);
1648extern int register_trigger_hist_enable_disable_cmds(void);
1649extern bool event_trigger_check_remove(const char *glob);
1650extern bool event_trigger_empty_param(const char *param);
1651extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1652 char **filter, bool param_required);
1653extern struct event_trigger_data *
1654event_trigger_alloc(struct event_command *cmd_ops,
1655 char *cmd,
1656 char *param,
1657 void *private_data);
1658extern int event_trigger_parse_num(char *trigger,
1659 struct event_trigger_data *trigger_data);
1660extern int event_trigger_set_filter(struct event_command *cmd_ops,
1661 struct trace_event_file *file,
1662 char *param,
1663 struct event_trigger_data *trigger_data);
1664extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1665 struct event_trigger_data *trigger_data);
1666extern int event_trigger_register(struct event_command *cmd_ops,
1667 struct trace_event_file *file,
1668 char *glob,
1669 struct event_trigger_data *trigger_data);
1670extern void event_trigger_unregister(struct event_command *cmd_ops,
1671 struct trace_event_file *file,
1672 char *glob,
1673 struct event_trigger_data *trigger_data);
1674
1675extern void event_file_get(struct trace_event_file *file);
1676extern void event_file_put(struct trace_event_file *file);
1677
1678/**
1679 * struct event_trigger_ops - callbacks for trace event triggers
1680 *
1681 * The methods in this structure provide per-event trigger hooks for
1682 * various trigger operations.
1683 *
1684 * The @init and @free methods are used during trigger setup and
1685 * teardown, typically called from an event_command's @parse()
1686 * function implementation.
1687 *
1688 * The @print method is used to print the trigger spec.
1689 *
1690 * The @trigger method is the function that actually implements the
1691 * trigger and is called in the context of the triggering event
1692 * whenever that event occurs.
1693 *
1694 * All the methods below, except for @init() and @free(), must be
1695 * implemented.
1696 *
1697 * @trigger: The trigger 'probe' function called when the triggering
1698 * event occurs. The data passed into this callback is the data
1699 * that was supplied to the event_command @reg() function that
1700 * registered the trigger (see struct event_command) along with
1701 * the trace record, rec.
1702 *
1703 * @init: An optional initialization function called for the trigger
1704 * when the trigger is registered (via the event_command reg()
1705 * function). This can be used to perform per-trigger
1706 * initialization such as incrementing a per-trigger reference
1707 * count, for instance. This is usually implemented by the
1708 * generic utility function @event_trigger_init() (see
1709 * trace_event_triggers.c).
1710 *
1711 * @free: An optional de-initialization function called for the
1712 * trigger when the trigger is unregistered (via the
1713 * event_command @reg() function). This can be used to perform
1714 * per-trigger de-initialization such as decrementing a
1715 * per-trigger reference count and freeing corresponding trigger
1716 * data, for instance. This is usually implemented by the
1717 * generic utility function @event_trigger_free() (see
1718 * trace_event_triggers.c).
1719 *
1720 * @print: The callback function invoked to have the trigger print
1721 * itself. This is usually implemented by a wrapper function
1722 * that calls the generic utility function @event_trigger_print()
1723 * (see trace_event_triggers.c).
1724 */
1725struct event_trigger_ops {
1726 void (*trigger)(struct event_trigger_data *data,
1727 struct trace_buffer *buffer,
1728 void *rec,
1729 struct ring_buffer_event *rbe);
1730 int (*init)(struct event_trigger_data *data);
1731 void (*free)(struct event_trigger_data *data);
1732 int (*print)(struct seq_file *m,
1733 struct event_trigger_data *data);
1734};
1735
1736/**
1737 * struct event_command - callbacks and data members for event commands
1738 *
1739 * Event commands are invoked by users by writing the command name
1740 * into the 'trigger' file associated with a trace event. The
1741 * parameters associated with a specific invocation of an event
1742 * command are used to create an event trigger instance, which is
1743 * added to the list of trigger instances associated with that trace
1744 * event. When the event is hit, the set of triggers associated with
1745 * that event is invoked.
1746 *
1747 * The data members in this structure provide per-event command data
1748 * for various event commands.
1749 *
1750 * All the data members below, except for @post_trigger, must be set
1751 * for each event command.
1752 *
1753 * @name: The unique name that identifies the event command. This is
1754 * the name used when setting triggers via trigger files.
1755 *
1756 * @trigger_type: A unique id that identifies the event command
1757 * 'type'. This value has two purposes, the first to ensure that
1758 * only one trigger of the same type can be set at a given time
1759 * for a particular event e.g. it doesn't make sense to have both
1760 * a traceon and traceoff trigger attached to a single event at
1761 * the same time, so traceon and traceoff have the same type
1762 * though they have different names. The @trigger_type value is
1763 * also used as a bit value for deferring the actual trigger
1764 * action until after the current event is finished. Some
1765 * commands need to do this if they themselves log to the trace
1766 * buffer (see the @post_trigger() member below). @trigger_type
1767 * values are defined by adding new values to the trigger_type
1768 * enum in include/linux/trace_events.h.
1769 *
1770 * @flags: See the enum event_command_flags below.
1771 *
1772 * All the methods below, except for @set_filter() and @unreg_all(),
1773 * must be implemented.
1774 *
1775 * @parse: The callback function responsible for parsing and
1776 * registering the trigger written to the 'trigger' file by the
1777 * user. It allocates the trigger instance and registers it with
1778 * the appropriate trace event. It makes use of the other
1779 * event_command callback functions to orchestrate this, and is
1780 * usually implemented by the generic utility function
1781 * @event_trigger_callback() (see trace_event_triggers.c).
1782 *
1783 * @reg: Adds the trigger to the list of triggers associated with the
1784 * event, and enables the event trigger itself, after
1785 * initializing it (via the event_trigger_ops @init() function).
1786 * This is also where commands can use the @trigger_type value to
1787 * make the decision as to whether or not multiple instances of
1788 * the trigger should be allowed. This is usually implemented by
1789 * the generic utility function @register_trigger() (see
1790 * trace_event_triggers.c).
1791 *
1792 * @unreg: Removes the trigger from the list of triggers associated
1793 * with the event, and disables the event trigger itself, after
1794 * initializing it (via the event_trigger_ops @free() function).
1795 * This is usually implemented by the generic utility function
1796 * @unregister_trigger() (see trace_event_triggers.c).
1797 *
1798 * @unreg_all: An optional function called to remove all the triggers
1799 * from the list of triggers associated with the event. Called
1800 * when a trigger file is opened in truncate mode.
1801 *
1802 * @set_filter: An optional function called to parse and set a filter
1803 * for the trigger. If no @set_filter() method is set for the
1804 * event command, filters set by the user for the command will be
1805 * ignored. This is usually implemented by the generic utility
1806 * function @set_trigger_filter() (see trace_event_triggers.c).
1807 *
1808 * @get_trigger_ops: The callback function invoked to retrieve the
1809 * event_trigger_ops implementation associated with the command.
1810 * This callback function allows a single event_command to
1811 * support multiple trigger implementations via different sets of
1812 * event_trigger_ops, depending on the value of the @param
1813 * string.
1814 */
1815struct event_command {
1816 struct list_head list;
1817 char *name;
1818 enum event_trigger_type trigger_type;
1819 int flags;
1820 int (*parse)(struct event_command *cmd_ops,
1821 struct trace_event_file *file,
1822 char *glob, char *cmd,
1823 char *param_and_filter);
1824 int (*reg)(char *glob,
1825 struct event_trigger_data *data,
1826 struct trace_event_file *file);
1827 void (*unreg)(char *glob,
1828 struct event_trigger_data *data,
1829 struct trace_event_file *file);
1830 void (*unreg_all)(struct trace_event_file *file);
1831 int (*set_filter)(char *filter_str,
1832 struct event_trigger_data *data,
1833 struct trace_event_file *file);
1834 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1835};
1836
1837/**
1838 * enum event_command_flags - flags for struct event_command
1839 *
1840 * @POST_TRIGGER: A flag that says whether or not this command needs
1841 * to have its action delayed until after the current event has
1842 * been closed. Some triggers need to avoid being invoked while
1843 * an event is currently in the process of being logged, since
1844 * the trigger may itself log data into the trace buffer. Thus
1845 * we make sure the current event is committed before invoking
1846 * those triggers. To do that, the trigger invocation is split
1847 * in two - the first part checks the filter using the current
1848 * trace record; if a command has the @post_trigger flag set, it
1849 * sets a bit for itself in the return value, otherwise it
1850 * directly invokes the trigger. Once all commands have been
1851 * either invoked or set their return flag, the current record is
1852 * either committed or discarded. At that point, if any commands
1853 * have deferred their triggers, those commands are finally
1854 * invoked following the close of the current event. In other
1855 * words, if the event_trigger_ops @func() probe implementation
1856 * itself logs to the trace buffer, this flag should be set,
1857 * otherwise it can be left unspecified.
1858 *
1859 * @NEEDS_REC: A flag that says whether or not this command needs
1860 * access to the trace record in order to perform its function,
1861 * regardless of whether or not it has a filter associated with
1862 * it (filters make a trigger require access to the trace record
1863 * but are not always present).
1864 */
1865enum event_command_flags {
1866 EVENT_CMD_FL_POST_TRIGGER = 1,
1867 EVENT_CMD_FL_NEEDS_REC = 2,
1868};
1869
1870static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1871{
1872 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1873}
1874
1875static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1876{
1877 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1878}
1879
1880extern int trace_event_enable_disable(struct trace_event_file *file,
1881 int enable, int soft_disable);
1882extern int tracing_alloc_snapshot(void);
1883extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1884extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1885
1886extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1887extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1888
1889extern const char *__start___trace_bprintk_fmt[];
1890extern const char *__stop___trace_bprintk_fmt[];
1891
1892extern const char *__start___tracepoint_str[];
1893extern const char *__stop___tracepoint_str[];
1894
1895void trace_printk_control(bool enabled);
1896void trace_printk_start_comm(void);
1897int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1898int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1899
1900/* Used from boot time tracer */
1901extern int trace_set_options(struct trace_array *tr, char *option);
1902extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1903extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1904 unsigned long size, int cpu_id);
1905extern int tracing_set_cpumask(struct trace_array *tr,
1906 cpumask_var_t tracing_cpumask_new);
1907
1908
1909#define MAX_EVENT_NAME_LEN 64
1910
1911extern ssize_t trace_parse_run_command(struct file *file,
1912 const char __user *buffer, size_t count, loff_t *ppos,
1913 int (*createfn)(const char *));
1914
1915extern unsigned int err_pos(char *cmd, const char *str);
1916extern void tracing_log_err(struct trace_array *tr,
1917 const char *loc, const char *cmd,
1918 const char **errs, u8 type, u16 pos);
1919
1920/*
1921 * Normal trace_printk() and friends allocates special buffers
1922 * to do the manipulation, as well as saves the print formats
1923 * into sections to display. But the trace infrastructure wants
1924 * to use these without the added overhead at the price of being
1925 * a bit slower (used mainly for warnings, where we don't care
1926 * about performance). The internal_trace_puts() is for such
1927 * a purpose.
1928 */
1929#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1930
1931#undef FTRACE_ENTRY
1932#define FTRACE_ENTRY(call, struct_name, id, tstruct, print) \
1933 extern struct trace_event_call \
1934 __aligned(4) event_##call;
1935#undef FTRACE_ENTRY_DUP
1936#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \
1937 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1938#undef FTRACE_ENTRY_PACKED
1939#define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
1940 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
1941
1942#include "trace_entries.h"
1943
1944#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1945int perf_ftrace_event_register(struct trace_event_call *call,
1946 enum trace_reg type, void *data);
1947#else
1948#define perf_ftrace_event_register NULL
1949#endif
1950
1951#ifdef CONFIG_FTRACE_SYSCALLS
1952void init_ftrace_syscalls(void);
1953const char *get_syscall_name(int syscall);
1954#else
1955static inline void init_ftrace_syscalls(void) { }
1956static inline const char *get_syscall_name(int syscall)
1957{
1958 return NULL;
1959}
1960#endif
1961
1962#ifdef CONFIG_EVENT_TRACING
1963void trace_event_init(void);
1964void trace_event_eval_update(struct trace_eval_map **map, int len);
1965/* Used from boot time tracer */
1966extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
1967extern int trigger_process_regex(struct trace_event_file *file, char *buff);
1968#else
1969static inline void __init trace_event_init(void) { }
1970static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1971#endif
1972
1973#ifdef CONFIG_TRACER_SNAPSHOT
1974void tracing_snapshot_instance(struct trace_array *tr);
1975int tracing_alloc_snapshot_instance(struct trace_array *tr);
1976#else
1977static inline void tracing_snapshot_instance(struct trace_array *tr) { }
1978static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
1979{
1980 return 0;
1981}
1982#endif
1983
1984#ifdef CONFIG_PREEMPT_TRACER
1985void tracer_preempt_on(unsigned long a0, unsigned long a1);
1986void tracer_preempt_off(unsigned long a0, unsigned long a1);
1987#else
1988static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
1989static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
1990#endif
1991#ifdef CONFIG_IRQSOFF_TRACER
1992void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
1993void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
1994#else
1995static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
1996static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
1997#endif
1998
1999/*
2000 * Reset the state of the trace_iterator so that it can read consumed data.
2001 * Normally, the trace_iterator is used for reading the data when it is not
2002 * consumed, and must retain state.
2003 */
2004static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2005{
2006 memset_startat(iter, 0, seq);
2007 iter->pos = -1;
2008}
2009
2010/* Check the name is good for event/group/fields */
2011static inline bool __is_good_name(const char *name, bool hash_ok)
2012{
2013 if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
2014 return false;
2015 while (*++name != '\0') {
2016 if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
2017 (!hash_ok || *name != '-'))
2018 return false;
2019 }
2020 return true;
2021}
2022
2023/* Check the name is good for event/group/fields */
2024static inline bool is_good_name(const char *name)
2025{
2026 return __is_good_name(name, false);
2027}
2028
2029/* Check the name is good for system */
2030static inline bool is_good_system_name(const char *name)
2031{
2032 return __is_good_name(name, true);
2033}
2034
2035/* Convert certain expected symbols into '_' when generating event names */
2036static inline void sanitize_event_name(char *name)
2037{
2038 while (*name++ != '\0')
2039 if (*name == ':' || *name == '.')
2040 *name = '_';
2041}
2042
2043/*
2044 * This is a generic way to read and write a u64 value from a file in tracefs.
2045 *
2046 * The value is stored on the variable pointed by *val. The value needs
2047 * to be at least *min and at most *max. The write is protected by an
2048 * existing *lock.
2049 */
2050struct trace_min_max_param {
2051 struct mutex *lock;
2052 u64 *val;
2053 u64 *min;
2054 u64 *max;
2055};
2056
2057#define U64_STR_SIZE 24 /* 20 digits max */
2058
2059extern const struct file_operations trace_min_max_fops;
2060
2061#ifdef CONFIG_RV
2062extern int rv_init_interface(void);
2063#else
2064static inline int rv_init_interface(void)
2065{
2066 return 0;
2067}
2068#endif
2069
2070#endif /* _LINUX_KERNEL_TRACE_H */
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
23#ifdef CONFIG_FTRACE_SYSCALLS
24#include <asm/unistd.h> /* For NR_SYSCALLS */
25#include <asm/syscall.h> /* some archs define it here */
26#endif
27
28enum trace_type {
29 __TRACE_FIRST_TYPE = 0,
30
31 TRACE_FN,
32 TRACE_CTX,
33 TRACE_WAKE,
34 TRACE_STACK,
35 TRACE_PRINT,
36 TRACE_BPRINT,
37 TRACE_MMIO_RW,
38 TRACE_MMIO_MAP,
39 TRACE_BRANCH,
40 TRACE_GRAPH_RET,
41 TRACE_GRAPH_ENT,
42 TRACE_USER_STACK,
43 TRACE_BLK,
44 TRACE_BPUTS,
45 TRACE_HWLAT,
46 TRACE_RAW_DATA,
47
48 __TRACE_LAST_TYPE,
49};
50
51
52#undef __field
53#define __field(type, item) type item;
54
55#undef __field_fn
56#define __field_fn(type, item) type item;
57
58#undef __field_struct
59#define __field_struct(type, item) __field(type, item)
60
61#undef __field_desc
62#define __field_desc(type, container, item)
63
64#undef __field_packed
65#define __field_packed(type, container, item)
66
67#undef __array
68#define __array(type, item, size) type item[size];
69
70#undef __array_desc
71#define __array_desc(type, container, item, size)
72
73#undef __dynamic_array
74#define __dynamic_array(type, item) type item[];
75
76#undef F_STRUCT
77#define F_STRUCT(args...) args
78
79#undef FTRACE_ENTRY
80#define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
81 struct struct_name { \
82 struct trace_entry ent; \
83 tstruct \
84 }
85
86#undef FTRACE_ENTRY_DUP
87#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
88
89#undef FTRACE_ENTRY_REG
90#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, regfn) \
91 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
92
93#undef FTRACE_ENTRY_PACKED
94#define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print) \
95 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
96
97#include "trace_entries.h"
98
99/* Use this for memory failure errors */
100#define MEM_FAIL(condition, fmt, ...) ({ \
101 static bool __section(.data.once) __warned; \
102 int __ret_warn_once = !!(condition); \
103 \
104 if (unlikely(__ret_warn_once && !__warned)) { \
105 __warned = true; \
106 pr_err("ERROR: " fmt, ##__VA_ARGS__); \
107 } \
108 unlikely(__ret_warn_once); \
109})
110
111/*
112 * syscalls are special, and need special handling, this is why
113 * they are not included in trace_entries.h
114 */
115struct syscall_trace_enter {
116 struct trace_entry ent;
117 int nr;
118 unsigned long args[];
119};
120
121struct syscall_trace_exit {
122 struct trace_entry ent;
123 int nr;
124 long ret;
125};
126
127struct kprobe_trace_entry_head {
128 struct trace_entry ent;
129 unsigned long ip;
130};
131
132struct kretprobe_trace_entry_head {
133 struct trace_entry ent;
134 unsigned long func;
135 unsigned long ret_ip;
136};
137
138/*
139 * trace_flag_type is an enumeration that holds different
140 * states when a trace occurs. These are:
141 * IRQS_OFF - interrupts were disabled
142 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
143 * NEED_RESCHED - reschedule is requested
144 * HARDIRQ - inside an interrupt handler
145 * SOFTIRQ - inside a softirq handler
146 */
147enum trace_flag_type {
148 TRACE_FLAG_IRQS_OFF = 0x01,
149 TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
150 TRACE_FLAG_NEED_RESCHED = 0x04,
151 TRACE_FLAG_HARDIRQ = 0x08,
152 TRACE_FLAG_SOFTIRQ = 0x10,
153 TRACE_FLAG_PREEMPT_RESCHED = 0x20,
154 TRACE_FLAG_NMI = 0x40,
155};
156
157#define TRACE_BUF_SIZE 1024
158
159struct trace_array;
160
161/*
162 * The CPU trace array - it consists of thousands of trace entries
163 * plus some other descriptor data: (for example which task started
164 * the trace, etc.)
165 */
166struct trace_array_cpu {
167 atomic_t disabled;
168 void *buffer_page; /* ring buffer spare */
169
170 unsigned long entries;
171 unsigned long saved_latency;
172 unsigned long critical_start;
173 unsigned long critical_end;
174 unsigned long critical_sequence;
175 unsigned long nice;
176 unsigned long policy;
177 unsigned long rt_priority;
178 unsigned long skipped_entries;
179 u64 preempt_timestamp;
180 pid_t pid;
181 kuid_t uid;
182 char comm[TASK_COMM_LEN];
183
184#ifdef CONFIG_FUNCTION_TRACER
185 int ftrace_ignore_pid;
186#endif
187 bool ignore_pid;
188};
189
190struct tracer;
191struct trace_option_dentry;
192
193struct array_buffer {
194 struct trace_array *tr;
195 struct trace_buffer *buffer;
196 struct trace_array_cpu __percpu *data;
197 u64 time_start;
198 int cpu;
199};
200
201#define TRACE_FLAGS_MAX_SIZE 32
202
203struct trace_options {
204 struct tracer *tracer;
205 struct trace_option_dentry *topts;
206};
207
208struct trace_pid_list {
209 int pid_max;
210 unsigned long *pids;
211};
212
213enum {
214 TRACE_PIDS = BIT(0),
215 TRACE_NO_PIDS = BIT(1),
216};
217
218static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
219 struct trace_pid_list *no_pid_list)
220{
221 /* Return true if the pid list in type has pids */
222 return ((type & TRACE_PIDS) && pid_list) ||
223 ((type & TRACE_NO_PIDS) && no_pid_list);
224}
225
226static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
227 struct trace_pid_list *no_pid_list)
228{
229 /*
230 * Turning off what is in @type, return true if the "other"
231 * pid list, still has pids in it.
232 */
233 return (!(type & TRACE_PIDS) && pid_list) ||
234 (!(type & TRACE_NO_PIDS) && no_pid_list);
235}
236
237typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
238
239/**
240 * struct cond_snapshot - conditional snapshot data and callback
241 *
242 * The cond_snapshot structure encapsulates a callback function and
243 * data associated with the snapshot for a given tracing instance.
244 *
245 * When a snapshot is taken conditionally, by invoking
246 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
247 * passed in turn to the cond_snapshot.update() function. That data
248 * can be compared by the update() implementation with the cond_data
249 * contained wihin the struct cond_snapshot instance associated with
250 * the trace_array. Because the tr->max_lock is held throughout the
251 * update() call, the update() function can directly retrieve the
252 * cond_snapshot and cond_data associated with the per-instance
253 * snapshot associated with the trace_array.
254 *
255 * The cond_snapshot.update() implementation can save data to be
256 * associated with the snapshot if it decides to, and returns 'true'
257 * in that case, or it returns 'false' if the conditional snapshot
258 * shouldn't be taken.
259 *
260 * The cond_snapshot instance is created and associated with the
261 * user-defined cond_data by tracing_cond_snapshot_enable().
262 * Likewise, the cond_snapshot instance is destroyed and is no longer
263 * associated with the trace instance by
264 * tracing_cond_snapshot_disable().
265 *
266 * The method below is required.
267 *
268 * @update: When a conditional snapshot is invoked, the update()
269 * callback function is invoked with the tr->max_lock held. The
270 * update() implementation signals whether or not to actually
271 * take the snapshot, by returning 'true' if so, 'false' if no
272 * snapshot should be taken. Because the max_lock is held for
273 * the duration of update(), the implementation is safe to
274 * directly retrieven and save any implementation data it needs
275 * to in association with the snapshot.
276 */
277struct cond_snapshot {
278 void *cond_data;
279 cond_update_fn_t update;
280};
281
282/*
283 * The trace array - an array of per-CPU trace arrays. This is the
284 * highest level data structure that individual tracers deal with.
285 * They have on/off state as well:
286 */
287struct trace_array {
288 struct list_head list;
289 char *name;
290 struct array_buffer array_buffer;
291#ifdef CONFIG_TRACER_MAX_TRACE
292 /*
293 * The max_buffer is used to snapshot the trace when a maximum
294 * latency is reached, or when the user initiates a snapshot.
295 * Some tracers will use this to store a maximum trace while
296 * it continues examining live traces.
297 *
298 * The buffers for the max_buffer are set up the same as the array_buffer
299 * When a snapshot is taken, the buffer of the max_buffer is swapped
300 * with the buffer of the array_buffer and the buffers are reset for
301 * the array_buffer so the tracing can continue.
302 */
303 struct array_buffer max_buffer;
304 bool allocated_snapshot;
305#endif
306#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
307 unsigned long max_latency;
308#ifdef CONFIG_FSNOTIFY
309 struct dentry *d_max_latency;
310 struct work_struct fsnotify_work;
311 struct irq_work fsnotify_irqwork;
312#endif
313#endif
314 struct trace_pid_list __rcu *filtered_pids;
315 struct trace_pid_list __rcu *filtered_no_pids;
316 /*
317 * max_lock is used to protect the swapping of buffers
318 * when taking a max snapshot. The buffers themselves are
319 * protected by per_cpu spinlocks. But the action of the swap
320 * needs its own lock.
321 *
322 * This is defined as a arch_spinlock_t in order to help
323 * with performance when lockdep debugging is enabled.
324 *
325 * It is also used in other places outside the update_max_tr
326 * so it needs to be defined outside of the
327 * CONFIG_TRACER_MAX_TRACE.
328 */
329 arch_spinlock_t max_lock;
330 int buffer_disabled;
331#ifdef CONFIG_FTRACE_SYSCALLS
332 int sys_refcount_enter;
333 int sys_refcount_exit;
334 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
335 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
336#endif
337 int stop_count;
338 int clock_id;
339 int nr_topts;
340 bool clear_trace;
341 int buffer_percent;
342 unsigned int n_err_log_entries;
343 struct tracer *current_trace;
344 unsigned int trace_flags;
345 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
346 unsigned int flags;
347 raw_spinlock_t start_lock;
348 struct list_head err_log;
349 struct dentry *dir;
350 struct dentry *options;
351 struct dentry *percpu_dir;
352 struct dentry *event_dir;
353 struct trace_options *topts;
354 struct list_head systems;
355 struct list_head events;
356 struct trace_event_file *trace_marker_file;
357 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
358 int ref;
359 int trace_ref;
360#ifdef CONFIG_FUNCTION_TRACER
361 struct ftrace_ops *ops;
362 struct trace_pid_list __rcu *function_pids;
363 struct trace_pid_list __rcu *function_no_pids;
364#ifdef CONFIG_DYNAMIC_FTRACE
365 /* All of these are protected by the ftrace_lock */
366 struct list_head func_probes;
367 struct list_head mod_trace;
368 struct list_head mod_notrace;
369#endif
370 /* function tracing enabled */
371 int function_enabled;
372#endif
373 int time_stamp_abs_ref;
374 struct list_head hist_vars;
375#ifdef CONFIG_TRACER_SNAPSHOT
376 struct cond_snapshot *cond_snapshot;
377#endif
378};
379
380enum {
381 TRACE_ARRAY_FL_GLOBAL = (1 << 0)
382};
383
384extern struct list_head ftrace_trace_arrays;
385
386extern struct mutex trace_types_lock;
387
388extern int trace_array_get(struct trace_array *tr);
389extern int tracing_check_open_get_tr(struct trace_array *tr);
390extern struct trace_array *trace_array_find(const char *instance);
391extern struct trace_array *trace_array_find_get(const char *instance);
392
393extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs);
394extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
395
396extern bool trace_clock_in_ns(struct trace_array *tr);
397
398/*
399 * The global tracer (top) should be the first trace array added,
400 * but we check the flag anyway.
401 */
402static inline struct trace_array *top_trace_array(void)
403{
404 struct trace_array *tr;
405
406 if (list_empty(&ftrace_trace_arrays))
407 return NULL;
408
409 tr = list_entry(ftrace_trace_arrays.prev,
410 typeof(*tr), list);
411 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
412 return tr;
413}
414
415#define FTRACE_CMP_TYPE(var, type) \
416 __builtin_types_compatible_p(typeof(var), type *)
417
418#undef IF_ASSIGN
419#define IF_ASSIGN(var, entry, etype, id) \
420 if (FTRACE_CMP_TYPE(var, etype)) { \
421 var = (typeof(var))(entry); \
422 WARN_ON(id != 0 && (entry)->type != id); \
423 break; \
424 }
425
426/* Will cause compile errors if type is not found. */
427extern void __ftrace_bad_type(void);
428
429/*
430 * The trace_assign_type is a verifier that the entry type is
431 * the same as the type being assigned. To add new types simply
432 * add a line with the following format:
433 *
434 * IF_ASSIGN(var, ent, type, id);
435 *
436 * Where "type" is the trace type that includes the trace_entry
437 * as the "ent" item. And "id" is the trace identifier that is
438 * used in the trace_type enum.
439 *
440 * If the type can have more than one id, then use zero.
441 */
442#define trace_assign_type(var, ent) \
443 do { \
444 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
445 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
446 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
447 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
448 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
449 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
450 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
451 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
452 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
453 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
454 TRACE_MMIO_RW); \
455 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
456 TRACE_MMIO_MAP); \
457 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
458 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
459 TRACE_GRAPH_ENT); \
460 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
461 TRACE_GRAPH_RET); \
462 __ftrace_bad_type(); \
463 } while (0)
464
465/*
466 * An option specific to a tracer. This is a boolean value.
467 * The bit is the bit index that sets its value on the
468 * flags value in struct tracer_flags.
469 */
470struct tracer_opt {
471 const char *name; /* Will appear on the trace_options file */
472 u32 bit; /* Mask assigned in val field in tracer_flags */
473};
474
475/*
476 * The set of specific options for a tracer. Your tracer
477 * have to set the initial value of the flags val.
478 */
479struct tracer_flags {
480 u32 val;
481 struct tracer_opt *opts;
482 struct tracer *trace;
483};
484
485/* Makes more easy to define a tracer opt */
486#define TRACER_OPT(s, b) .name = #s, .bit = b
487
488
489struct trace_option_dentry {
490 struct tracer_opt *opt;
491 struct tracer_flags *flags;
492 struct trace_array *tr;
493 struct dentry *entry;
494};
495
496/**
497 * struct tracer - a specific tracer and its callbacks to interact with tracefs
498 * @name: the name chosen to select it on the available_tracers file
499 * @init: called when one switches to this tracer (echo name > current_tracer)
500 * @reset: called when one switches to another tracer
501 * @start: called when tracing is unpaused (echo 1 > tracing_on)
502 * @stop: called when tracing is paused (echo 0 > tracing_on)
503 * @update_thresh: called when tracing_thresh is updated
504 * @open: called when the trace file is opened
505 * @pipe_open: called when the trace_pipe file is opened
506 * @close: called when the trace file is released
507 * @pipe_close: called when the trace_pipe file is released
508 * @read: override the default read callback on trace_pipe
509 * @splice_read: override the default splice_read callback on trace_pipe
510 * @selftest: selftest to run on boot (see trace_selftest.c)
511 * @print_headers: override the first lines that describe your columns
512 * @print_line: callback that prints a trace
513 * @set_flag: signals one of your private flags changed (trace_options file)
514 * @flags: your private flags
515 */
516struct tracer {
517 const char *name;
518 int (*init)(struct trace_array *tr);
519 void (*reset)(struct trace_array *tr);
520 void (*start)(struct trace_array *tr);
521 void (*stop)(struct trace_array *tr);
522 int (*update_thresh)(struct trace_array *tr);
523 void (*open)(struct trace_iterator *iter);
524 void (*pipe_open)(struct trace_iterator *iter);
525 void (*close)(struct trace_iterator *iter);
526 void (*pipe_close)(struct trace_iterator *iter);
527 ssize_t (*read)(struct trace_iterator *iter,
528 struct file *filp, char __user *ubuf,
529 size_t cnt, loff_t *ppos);
530 ssize_t (*splice_read)(struct trace_iterator *iter,
531 struct file *filp,
532 loff_t *ppos,
533 struct pipe_inode_info *pipe,
534 size_t len,
535 unsigned int flags);
536#ifdef CONFIG_FTRACE_STARTUP_TEST
537 int (*selftest)(struct tracer *trace,
538 struct trace_array *tr);
539#endif
540 void (*print_header)(struct seq_file *m);
541 enum print_line_t (*print_line)(struct trace_iterator *iter);
542 /* If you handled the flag setting, return 0 */
543 int (*set_flag)(struct trace_array *tr,
544 u32 old_flags, u32 bit, int set);
545 /* Return 0 if OK with change, else return non-zero */
546 int (*flag_changed)(struct trace_array *tr,
547 u32 mask, int set);
548 struct tracer *next;
549 struct tracer_flags *flags;
550 int enabled;
551 bool print_max;
552 bool allow_instances;
553#ifdef CONFIG_TRACER_MAX_TRACE
554 bool use_max_tr;
555#endif
556 /* True if tracer cannot be enabled in kernel param */
557 bool noboot;
558};
559
560
561/* Only current can touch trace_recursion */
562
563/*
564 * For function tracing recursion:
565 * The order of these bits are important.
566 *
567 * When function tracing occurs, the following steps are made:
568 * If arch does not support a ftrace feature:
569 * call internal function (uses INTERNAL bits) which calls...
570 * If callback is registered to the "global" list, the list
571 * function is called and recursion checks the GLOBAL bits.
572 * then this function calls...
573 * The function callback, which can use the FTRACE bits to
574 * check for recursion.
575 *
576 * Now if the arch does not suppport a feature, and it calls
577 * the global list function which calls the ftrace callback
578 * all three of these steps will do a recursion protection.
579 * There's no reason to do one if the previous caller already
580 * did. The recursion that we are protecting against will
581 * go through the same steps again.
582 *
583 * To prevent the multiple recursion checks, if a recursion
584 * bit is set that is higher than the MAX bit of the current
585 * check, then we know that the check was made by the previous
586 * caller, and we can skip the current check.
587 */
588enum {
589 /* Function recursion bits */
590 TRACE_FTRACE_BIT,
591 TRACE_FTRACE_NMI_BIT,
592 TRACE_FTRACE_IRQ_BIT,
593 TRACE_FTRACE_SIRQ_BIT,
594
595 /* INTERNAL_BITs must be greater than FTRACE_BITs */
596 TRACE_INTERNAL_BIT,
597 TRACE_INTERNAL_NMI_BIT,
598 TRACE_INTERNAL_IRQ_BIT,
599 TRACE_INTERNAL_SIRQ_BIT,
600
601 TRACE_BRANCH_BIT,
602/*
603 * Abuse of the trace_recursion.
604 * As we need a way to maintain state if we are tracing the function
605 * graph in irq because we want to trace a particular function that
606 * was called in irq context but we have irq tracing off. Since this
607 * can only be modified by current, we can reuse trace_recursion.
608 */
609 TRACE_IRQ_BIT,
610
611 /* Set if the function is in the set_graph_function file */
612 TRACE_GRAPH_BIT,
613
614 /*
615 * In the very unlikely case that an interrupt came in
616 * at a start of graph tracing, and we want to trace
617 * the function in that interrupt, the depth can be greater
618 * than zero, because of the preempted start of a previous
619 * trace. In an even more unlikely case, depth could be 2
620 * if a softirq interrupted the start of graph tracing,
621 * followed by an interrupt preempting a start of graph
622 * tracing in the softirq, and depth can even be 3
623 * if an NMI came in at the start of an interrupt function
624 * that preempted a softirq start of a function that
625 * preempted normal context!!!! Luckily, it can't be
626 * greater than 3, so the next two bits are a mask
627 * of what the depth is when we set TRACE_GRAPH_BIT
628 */
629
630 TRACE_GRAPH_DEPTH_START_BIT,
631 TRACE_GRAPH_DEPTH_END_BIT,
632
633 /*
634 * To implement set_graph_notrace, if this bit is set, we ignore
635 * function graph tracing of called functions, until the return
636 * function is called to clear it.
637 */
638 TRACE_GRAPH_NOTRACE_BIT,
639};
640
641#define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
642#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
643#define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit)))
644
645#define trace_recursion_depth() \
646 (((current)->trace_recursion >> TRACE_GRAPH_DEPTH_START_BIT) & 3)
647#define trace_recursion_set_depth(depth) \
648 do { \
649 current->trace_recursion &= \
650 ~(3 << TRACE_GRAPH_DEPTH_START_BIT); \
651 current->trace_recursion |= \
652 ((depth) & 3) << TRACE_GRAPH_DEPTH_START_BIT; \
653 } while (0)
654
655#define TRACE_CONTEXT_BITS 4
656
657#define TRACE_FTRACE_START TRACE_FTRACE_BIT
658#define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
659
660#define TRACE_LIST_START TRACE_INTERNAL_BIT
661#define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
662
663#define TRACE_CONTEXT_MASK TRACE_LIST_MAX
664
665static __always_inline int trace_get_context_bit(void)
666{
667 int bit;
668
669 if (in_interrupt()) {
670 if (in_nmi())
671 bit = 0;
672
673 else if (in_irq())
674 bit = 1;
675 else
676 bit = 2;
677 } else
678 bit = 3;
679
680 return bit;
681}
682
683static __always_inline int trace_test_and_set_recursion(int start, int max)
684{
685 unsigned int val = current->trace_recursion;
686 int bit;
687
688 /* A previous recursion check was made */
689 if ((val & TRACE_CONTEXT_MASK) > max)
690 return 0;
691
692 bit = trace_get_context_bit() + start;
693 if (unlikely(val & (1 << bit)))
694 return -1;
695
696 val |= 1 << bit;
697 current->trace_recursion = val;
698 barrier();
699
700 return bit;
701}
702
703static __always_inline void trace_clear_recursion(int bit)
704{
705 unsigned int val = current->trace_recursion;
706
707 if (!bit)
708 return;
709
710 bit = 1 << bit;
711 val &= ~bit;
712
713 barrier();
714 current->trace_recursion = val;
715}
716
717static inline struct ring_buffer_iter *
718trace_buffer_iter(struct trace_iterator *iter, int cpu)
719{
720 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
721}
722
723int tracer_init(struct tracer *t, struct trace_array *tr);
724int tracing_is_enabled(void);
725void tracing_reset_online_cpus(struct array_buffer *buf);
726void tracing_reset_current(int cpu);
727void tracing_reset_all_online_cpus(void);
728int tracing_open_generic(struct inode *inode, struct file *filp);
729int tracing_open_generic_tr(struct inode *inode, struct file *filp);
730bool tracing_is_disabled(void);
731bool tracer_tracing_is_on(struct trace_array *tr);
732void tracer_tracing_on(struct trace_array *tr);
733void tracer_tracing_off(struct trace_array *tr);
734struct dentry *trace_create_file(const char *name,
735 umode_t mode,
736 struct dentry *parent,
737 void *data,
738 const struct file_operations *fops);
739
740struct dentry *tracing_init_dentry(void);
741
742struct ring_buffer_event;
743
744struct ring_buffer_event *
745trace_buffer_lock_reserve(struct trace_buffer *buffer,
746 int type,
747 unsigned long len,
748 unsigned long flags,
749 int pc);
750
751struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
752 struct trace_array_cpu *data);
753
754struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
755 int *ent_cpu, u64 *ent_ts);
756
757void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
758 struct ring_buffer_event *event);
759
760int trace_empty(struct trace_iterator *iter);
761
762void *trace_find_next_entry_inc(struct trace_iterator *iter);
763
764void trace_init_global_iter(struct trace_iterator *iter);
765
766void tracing_iter_reset(struct trace_iterator *iter, int cpu);
767
768unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
769unsigned long trace_total_entries(struct trace_array *tr);
770
771void trace_function(struct trace_array *tr,
772 unsigned long ip,
773 unsigned long parent_ip,
774 unsigned long flags, int pc);
775void trace_graph_function(struct trace_array *tr,
776 unsigned long ip,
777 unsigned long parent_ip,
778 unsigned long flags, int pc);
779void trace_latency_header(struct seq_file *m);
780void trace_default_header(struct seq_file *m);
781void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
782int trace_empty(struct trace_iterator *iter);
783
784void trace_graph_return(struct ftrace_graph_ret *trace);
785int trace_graph_entry(struct ftrace_graph_ent *trace);
786void set_graph_array(struct trace_array *tr);
787
788void tracing_start_cmdline_record(void);
789void tracing_stop_cmdline_record(void);
790void tracing_start_tgid_record(void);
791void tracing_stop_tgid_record(void);
792
793int register_tracer(struct tracer *type);
794int is_tracing_stopped(void);
795
796loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
797
798extern cpumask_var_t __read_mostly tracing_buffer_mask;
799
800#define for_each_tracing_cpu(cpu) \
801 for_each_cpu(cpu, tracing_buffer_mask)
802
803extern unsigned long nsecs_to_usecs(unsigned long nsecs);
804
805extern unsigned long tracing_thresh;
806
807/* PID filtering */
808
809extern int pid_max;
810
811bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
812 pid_t search_pid);
813bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
814 struct trace_pid_list *filtered_no_pids,
815 struct task_struct *task);
816void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
817 struct task_struct *self,
818 struct task_struct *task);
819void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
820void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
821int trace_pid_show(struct seq_file *m, void *v);
822void trace_free_pid_list(struct trace_pid_list *pid_list);
823int trace_pid_write(struct trace_pid_list *filtered_pids,
824 struct trace_pid_list **new_pid_list,
825 const char __user *ubuf, size_t cnt);
826
827#ifdef CONFIG_TRACER_MAX_TRACE
828void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
829 void *cond_data);
830void update_max_tr_single(struct trace_array *tr,
831 struct task_struct *tsk, int cpu);
832#endif /* CONFIG_TRACER_MAX_TRACE */
833
834#if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \
835 defined(CONFIG_FSNOTIFY)
836
837void latency_fsnotify(struct trace_array *tr);
838
839#else
840
841static inline void latency_fsnotify(struct trace_array *tr) { }
842
843#endif
844
845#ifdef CONFIG_STACKTRACE
846void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
847 int pc);
848#else
849static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
850 int skip, int pc)
851{
852}
853#endif /* CONFIG_STACKTRACE */
854
855extern u64 ftrace_now(int cpu);
856
857extern void trace_find_cmdline(int pid, char comm[]);
858extern int trace_find_tgid(int pid);
859extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
860
861#ifdef CONFIG_DYNAMIC_FTRACE
862extern unsigned long ftrace_update_tot_cnt;
863extern unsigned long ftrace_number_of_pages;
864extern unsigned long ftrace_number_of_groups;
865void ftrace_init_trace_array(struct trace_array *tr);
866#else
867static inline void ftrace_init_trace_array(struct trace_array *tr) { }
868#endif
869#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
870extern int DYN_FTRACE_TEST_NAME(void);
871#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
872extern int DYN_FTRACE_TEST_NAME2(void);
873
874extern bool ring_buffer_expanded;
875extern bool tracing_selftest_disabled;
876
877#ifdef CONFIG_FTRACE_STARTUP_TEST
878extern int trace_selftest_startup_function(struct tracer *trace,
879 struct trace_array *tr);
880extern int trace_selftest_startup_function_graph(struct tracer *trace,
881 struct trace_array *tr);
882extern int trace_selftest_startup_irqsoff(struct tracer *trace,
883 struct trace_array *tr);
884extern int trace_selftest_startup_preemptoff(struct tracer *trace,
885 struct trace_array *tr);
886extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
887 struct trace_array *tr);
888extern int trace_selftest_startup_wakeup(struct tracer *trace,
889 struct trace_array *tr);
890extern int trace_selftest_startup_nop(struct tracer *trace,
891 struct trace_array *tr);
892extern int trace_selftest_startup_branch(struct tracer *trace,
893 struct trace_array *tr);
894/*
895 * Tracer data references selftest functions that only occur
896 * on boot up. These can be __init functions. Thus, when selftests
897 * are enabled, then the tracers need to reference __init functions.
898 */
899#define __tracer_data __refdata
900#else
901/* Tracers are seldom changed. Optimize when selftests are disabled. */
902#define __tracer_data __read_mostly
903#endif /* CONFIG_FTRACE_STARTUP_TEST */
904
905extern void *head_page(struct trace_array_cpu *data);
906extern unsigned long long ns2usecs(u64 nsec);
907extern int
908trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
909extern int
910trace_vprintk(unsigned long ip, const char *fmt, va_list args);
911extern int
912trace_array_vprintk(struct trace_array *tr,
913 unsigned long ip, const char *fmt, va_list args);
914int trace_array_printk_buf(struct trace_buffer *buffer,
915 unsigned long ip, const char *fmt, ...);
916void trace_printk_seq(struct trace_seq *s);
917enum print_line_t print_trace_line(struct trace_iterator *iter);
918
919extern char trace_find_mark(unsigned long long duration);
920
921struct ftrace_hash;
922
923struct ftrace_mod_load {
924 struct list_head list;
925 char *func;
926 char *module;
927 int enable;
928};
929
930enum {
931 FTRACE_HASH_FL_MOD = (1 << 0),
932};
933
934struct ftrace_hash {
935 unsigned long size_bits;
936 struct hlist_head *buckets;
937 unsigned long count;
938 unsigned long flags;
939 struct rcu_head rcu;
940};
941
942struct ftrace_func_entry *
943ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
944
945static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
946{
947 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
948}
949
950/* Standard output formatting function used for function return traces */
951#ifdef CONFIG_FUNCTION_GRAPH_TRACER
952
953/* Flag options */
954#define TRACE_GRAPH_PRINT_OVERRUN 0x1
955#define TRACE_GRAPH_PRINT_CPU 0x2
956#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
957#define TRACE_GRAPH_PRINT_PROC 0x8
958#define TRACE_GRAPH_PRINT_DURATION 0x10
959#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
960#define TRACE_GRAPH_PRINT_REL_TIME 0x40
961#define TRACE_GRAPH_PRINT_IRQS 0x80
962#define TRACE_GRAPH_PRINT_TAIL 0x100
963#define TRACE_GRAPH_SLEEP_TIME 0x200
964#define TRACE_GRAPH_GRAPH_TIME 0x400
965#define TRACE_GRAPH_PRINT_FILL_SHIFT 28
966#define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
967
968extern void ftrace_graph_sleep_time_control(bool enable);
969
970#ifdef CONFIG_FUNCTION_PROFILER
971extern void ftrace_graph_graph_time_control(bool enable);
972#else
973static inline void ftrace_graph_graph_time_control(bool enable) { }
974#endif
975
976extern enum print_line_t
977print_graph_function_flags(struct trace_iterator *iter, u32 flags);
978extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
979extern void
980trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
981extern void graph_trace_open(struct trace_iterator *iter);
982extern void graph_trace_close(struct trace_iterator *iter);
983extern int __trace_graph_entry(struct trace_array *tr,
984 struct ftrace_graph_ent *trace,
985 unsigned long flags, int pc);
986extern void __trace_graph_return(struct trace_array *tr,
987 struct ftrace_graph_ret *trace,
988 unsigned long flags, int pc);
989
990#ifdef CONFIG_DYNAMIC_FTRACE
991extern struct ftrace_hash __rcu *ftrace_graph_hash;
992extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
993
994static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
995{
996 unsigned long addr = trace->func;
997 int ret = 0;
998 struct ftrace_hash *hash;
999
1000 preempt_disable_notrace();
1001
1002 /*
1003 * Have to open code "rcu_dereference_sched()" because the
1004 * function graph tracer can be called when RCU is not
1005 * "watching".
1006 * Protected with schedule_on_each_cpu(ftrace_sync)
1007 */
1008 hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
1009
1010 if (ftrace_hash_empty(hash)) {
1011 ret = 1;
1012 goto out;
1013 }
1014
1015 if (ftrace_lookup_ip(hash, addr)) {
1016
1017 /*
1018 * This needs to be cleared on the return functions
1019 * when the depth is zero.
1020 */
1021 trace_recursion_set(TRACE_GRAPH_BIT);
1022 trace_recursion_set_depth(trace->depth);
1023
1024 /*
1025 * If no irqs are to be traced, but a set_graph_function
1026 * is set, and called by an interrupt handler, we still
1027 * want to trace it.
1028 */
1029 if (in_irq())
1030 trace_recursion_set(TRACE_IRQ_BIT);
1031 else
1032 trace_recursion_clear(TRACE_IRQ_BIT);
1033 ret = 1;
1034 }
1035
1036out:
1037 preempt_enable_notrace();
1038 return ret;
1039}
1040
1041static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
1042{
1043 if (trace_recursion_test(TRACE_GRAPH_BIT) &&
1044 trace->depth == trace_recursion_depth())
1045 trace_recursion_clear(TRACE_GRAPH_BIT);
1046}
1047
1048static inline int ftrace_graph_notrace_addr(unsigned long addr)
1049{
1050 int ret = 0;
1051 struct ftrace_hash *notrace_hash;
1052
1053 preempt_disable_notrace();
1054
1055 /*
1056 * Have to open code "rcu_dereference_sched()" because the
1057 * function graph tracer can be called when RCU is not
1058 * "watching".
1059 * Protected with schedule_on_each_cpu(ftrace_sync)
1060 */
1061 notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
1062 !preemptible());
1063
1064 if (ftrace_lookup_ip(notrace_hash, addr))
1065 ret = 1;
1066
1067 preempt_enable_notrace();
1068 return ret;
1069}
1070#else
1071static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)
1072{
1073 return 1;
1074}
1075
1076static inline int ftrace_graph_notrace_addr(unsigned long addr)
1077{
1078 return 0;
1079}
1080static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
1081{ }
1082#endif /* CONFIG_DYNAMIC_FTRACE */
1083
1084extern unsigned int fgraph_max_depth;
1085
1086static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
1087{
1088 /* trace it when it is-nested-in or is a function enabled. */
1089 return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
1090 ftrace_graph_addr(trace)) ||
1091 (trace->depth < 0) ||
1092 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
1093}
1094
1095#else /* CONFIG_FUNCTION_GRAPH_TRACER */
1096static inline enum print_line_t
1097print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1098{
1099 return TRACE_TYPE_UNHANDLED;
1100}
1101#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1102
1103extern struct list_head ftrace_pids;
1104
1105#ifdef CONFIG_FUNCTION_TRACER
1106
1107#define FTRACE_PID_IGNORE -1
1108#define FTRACE_PID_TRACE -2
1109
1110struct ftrace_func_command {
1111 struct list_head list;
1112 char *name;
1113 int (*func)(struct trace_array *tr,
1114 struct ftrace_hash *hash,
1115 char *func, char *cmd,
1116 char *params, int enable);
1117};
1118extern bool ftrace_filter_param __initdata;
1119static inline int ftrace_trace_task(struct trace_array *tr)
1120{
1121 return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1122 FTRACE_PID_IGNORE;
1123}
1124extern int ftrace_is_dead(void);
1125int ftrace_create_function_files(struct trace_array *tr,
1126 struct dentry *parent);
1127void ftrace_destroy_function_files(struct trace_array *tr);
1128void ftrace_init_global_array_ops(struct trace_array *tr);
1129void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1130void ftrace_reset_array_ops(struct trace_array *tr);
1131void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1132void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1133 struct dentry *d_tracer);
1134void ftrace_clear_pids(struct trace_array *tr);
1135int init_function_trace(void);
1136void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1137#else
1138static inline int ftrace_trace_task(struct trace_array *tr)
1139{
1140 return 1;
1141}
1142static inline int ftrace_is_dead(void) { return 0; }
1143static inline int
1144ftrace_create_function_files(struct trace_array *tr,
1145 struct dentry *parent)
1146{
1147 return 0;
1148}
1149static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1150static inline __init void
1151ftrace_init_global_array_ops(struct trace_array *tr) { }
1152static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
1153static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
1154static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
1155static inline void ftrace_clear_pids(struct trace_array *tr) { }
1156static inline int init_function_trace(void) { return 0; }
1157static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1158/* ftace_func_t type is not defined, use macro instead of static inline */
1159#define ftrace_init_array_ops(tr, func) do { } while (0)
1160#endif /* CONFIG_FUNCTION_TRACER */
1161
1162#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1163
1164struct ftrace_probe_ops {
1165 void (*func)(unsigned long ip,
1166 unsigned long parent_ip,
1167 struct trace_array *tr,
1168 struct ftrace_probe_ops *ops,
1169 void *data);
1170 int (*init)(struct ftrace_probe_ops *ops,
1171 struct trace_array *tr,
1172 unsigned long ip, void *init_data,
1173 void **data);
1174 void (*free)(struct ftrace_probe_ops *ops,
1175 struct trace_array *tr,
1176 unsigned long ip, void *data);
1177 int (*print)(struct seq_file *m,
1178 unsigned long ip,
1179 struct ftrace_probe_ops *ops,
1180 void *data);
1181};
1182
1183struct ftrace_func_mapper;
1184typedef int (*ftrace_mapper_func)(void *data);
1185
1186struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1187void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1188 unsigned long ip);
1189int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1190 unsigned long ip, void *data);
1191void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1192 unsigned long ip);
1193void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1194 ftrace_mapper_func free_func);
1195
1196extern int
1197register_ftrace_function_probe(char *glob, struct trace_array *tr,
1198 struct ftrace_probe_ops *ops, void *data);
1199extern int
1200unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1201 struct ftrace_probe_ops *ops);
1202extern void clear_ftrace_function_probes(struct trace_array *tr);
1203
1204int register_ftrace_command(struct ftrace_func_command *cmd);
1205int unregister_ftrace_command(struct ftrace_func_command *cmd);
1206
1207void ftrace_create_filter_files(struct ftrace_ops *ops,
1208 struct dentry *parent);
1209void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1210
1211extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1212 int len, int reset);
1213extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1214 int len, int reset);
1215#else
1216struct ftrace_func_command;
1217
1218static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1219{
1220 return -EINVAL;
1221}
1222static inline __init int unregister_ftrace_command(char *cmd_name)
1223{
1224 return -EINVAL;
1225}
1226static inline void clear_ftrace_function_probes(struct trace_array *tr)
1227{
1228}
1229
1230/*
1231 * The ops parameter passed in is usually undefined.
1232 * This must be a macro.
1233 */
1234#define ftrace_create_filter_files(ops, parent) do { } while (0)
1235#define ftrace_destroy_filter_files(ops) do { } while (0)
1236#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1237
1238bool ftrace_event_is_function(struct trace_event_call *call);
1239
1240/*
1241 * struct trace_parser - servers for reading the user input separated by spaces
1242 * @cont: set if the input is not complete - no final space char was found
1243 * @buffer: holds the parsed user input
1244 * @idx: user input length
1245 * @size: buffer size
1246 */
1247struct trace_parser {
1248 bool cont;
1249 char *buffer;
1250 unsigned idx;
1251 unsigned size;
1252};
1253
1254static inline bool trace_parser_loaded(struct trace_parser *parser)
1255{
1256 return (parser->idx != 0);
1257}
1258
1259static inline bool trace_parser_cont(struct trace_parser *parser)
1260{
1261 return parser->cont;
1262}
1263
1264static inline void trace_parser_clear(struct trace_parser *parser)
1265{
1266 parser->cont = false;
1267 parser->idx = 0;
1268}
1269
1270extern int trace_parser_get_init(struct trace_parser *parser, int size);
1271extern void trace_parser_put(struct trace_parser *parser);
1272extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1273 size_t cnt, loff_t *ppos);
1274
1275/*
1276 * Only create function graph options if function graph is configured.
1277 */
1278#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1279# define FGRAPH_FLAGS \
1280 C(DISPLAY_GRAPH, "display-graph"),
1281#else
1282# define FGRAPH_FLAGS
1283#endif
1284
1285#ifdef CONFIG_BRANCH_TRACER
1286# define BRANCH_FLAGS \
1287 C(BRANCH, "branch"),
1288#else
1289# define BRANCH_FLAGS
1290#endif
1291
1292#ifdef CONFIG_FUNCTION_TRACER
1293# define FUNCTION_FLAGS \
1294 C(FUNCTION, "function-trace"), \
1295 C(FUNC_FORK, "function-fork"),
1296# define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1297#else
1298# define FUNCTION_FLAGS
1299# define FUNCTION_DEFAULT_FLAGS 0UL
1300# define TRACE_ITER_FUNC_FORK 0UL
1301#endif
1302
1303#ifdef CONFIG_STACKTRACE
1304# define STACK_FLAGS \
1305 C(STACKTRACE, "stacktrace"),
1306#else
1307# define STACK_FLAGS
1308#endif
1309
1310/*
1311 * trace_iterator_flags is an enumeration that defines bit
1312 * positions into trace_flags that controls the output.
1313 *
1314 * NOTE: These bits must match the trace_options array in
1315 * trace.c (this macro guarantees it).
1316 */
1317#define TRACE_FLAGS \
1318 C(PRINT_PARENT, "print-parent"), \
1319 C(SYM_OFFSET, "sym-offset"), \
1320 C(SYM_ADDR, "sym-addr"), \
1321 C(VERBOSE, "verbose"), \
1322 C(RAW, "raw"), \
1323 C(HEX, "hex"), \
1324 C(BIN, "bin"), \
1325 C(BLOCK, "block"), \
1326 C(PRINTK, "trace_printk"), \
1327 C(ANNOTATE, "annotate"), \
1328 C(USERSTACKTRACE, "userstacktrace"), \
1329 C(SYM_USEROBJ, "sym-userobj"), \
1330 C(PRINTK_MSGONLY, "printk-msg-only"), \
1331 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1332 C(LATENCY_FMT, "latency-format"), \
1333 C(RECORD_CMD, "record-cmd"), \
1334 C(RECORD_TGID, "record-tgid"), \
1335 C(OVERWRITE, "overwrite"), \
1336 C(STOP_ON_FREE, "disable_on_free"), \
1337 C(IRQ_INFO, "irq-info"), \
1338 C(MARKERS, "markers"), \
1339 C(EVENT_FORK, "event-fork"), \
1340 C(PAUSE_ON_TRACE, "pause-on-trace"), \
1341 FUNCTION_FLAGS \
1342 FGRAPH_FLAGS \
1343 STACK_FLAGS \
1344 BRANCH_FLAGS
1345
1346/*
1347 * By defining C, we can make TRACE_FLAGS a list of bit names
1348 * that will define the bits for the flag masks.
1349 */
1350#undef C
1351#define C(a, b) TRACE_ITER_##a##_BIT
1352
1353enum trace_iterator_bits {
1354 TRACE_FLAGS
1355 /* Make sure we don't go more than we have bits for */
1356 TRACE_ITER_LAST_BIT
1357};
1358
1359/*
1360 * By redefining C, we can make TRACE_FLAGS a list of masks that
1361 * use the bits as defined above.
1362 */
1363#undef C
1364#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1365
1366enum trace_iterator_flags { TRACE_FLAGS };
1367
1368/*
1369 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1370 * control the output of kernel symbols.
1371 */
1372#define TRACE_ITER_SYM_MASK \
1373 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1374
1375extern struct tracer nop_trace;
1376
1377#ifdef CONFIG_BRANCH_TRACER
1378extern int enable_branch_tracing(struct trace_array *tr);
1379extern void disable_branch_tracing(void);
1380static inline int trace_branch_enable(struct trace_array *tr)
1381{
1382 if (tr->trace_flags & TRACE_ITER_BRANCH)
1383 return enable_branch_tracing(tr);
1384 return 0;
1385}
1386static inline void trace_branch_disable(void)
1387{
1388 /* due to races, always disable */
1389 disable_branch_tracing();
1390}
1391#else
1392static inline int trace_branch_enable(struct trace_array *tr)
1393{
1394 return 0;
1395}
1396static inline void trace_branch_disable(void)
1397{
1398}
1399#endif /* CONFIG_BRANCH_TRACER */
1400
1401/* set ring buffers to default size if not already done so */
1402int tracing_update_buffers(void);
1403
1404struct ftrace_event_field {
1405 struct list_head link;
1406 const char *name;
1407 const char *type;
1408 int filter_type;
1409 int offset;
1410 int size;
1411 int is_signed;
1412};
1413
1414struct prog_entry;
1415
1416struct event_filter {
1417 struct prog_entry __rcu *prog;
1418 char *filter_string;
1419};
1420
1421struct event_subsystem {
1422 struct list_head list;
1423 const char *name;
1424 struct event_filter *filter;
1425 int ref_count;
1426};
1427
1428struct trace_subsystem_dir {
1429 struct list_head list;
1430 struct event_subsystem *subsystem;
1431 struct trace_array *tr;
1432 struct dentry *entry;
1433 int ref_count;
1434 int nr_events;
1435};
1436
1437extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1438 struct trace_buffer *buffer,
1439 struct ring_buffer_event *event);
1440
1441void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1442 struct trace_buffer *buffer,
1443 struct ring_buffer_event *event,
1444 unsigned long flags, int pc,
1445 struct pt_regs *regs);
1446
1447static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1448 struct trace_buffer *buffer,
1449 struct ring_buffer_event *event,
1450 unsigned long flags, int pc)
1451{
1452 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
1453}
1454
1455DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1456DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1457void trace_buffered_event_disable(void);
1458void trace_buffered_event_enable(void);
1459
1460static inline void
1461__trace_event_discard_commit(struct trace_buffer *buffer,
1462 struct ring_buffer_event *event)
1463{
1464 if (this_cpu_read(trace_buffered_event) == event) {
1465 /* Simply release the temp buffer */
1466 this_cpu_dec(trace_buffered_event_cnt);
1467 return;
1468 }
1469 ring_buffer_discard_commit(buffer, event);
1470}
1471
1472/*
1473 * Helper function for event_trigger_unlock_commit{_regs}().
1474 * If there are event triggers attached to this event that requires
1475 * filtering against its fields, then they wil be called as the
1476 * entry already holds the field information of the current event.
1477 *
1478 * It also checks if the event should be discarded or not.
1479 * It is to be discarded if the event is soft disabled and the
1480 * event was only recorded to process triggers, or if the event
1481 * filter is active and this event did not match the filters.
1482 *
1483 * Returns true if the event is discarded, false otherwise.
1484 */
1485static inline bool
1486__event_trigger_test_discard(struct trace_event_file *file,
1487 struct trace_buffer *buffer,
1488 struct ring_buffer_event *event,
1489 void *entry,
1490 enum event_trigger_type *tt)
1491{
1492 unsigned long eflags = file->flags;
1493
1494 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1495 *tt = event_triggers_call(file, entry, event);
1496
1497 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1498 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1499 !filter_match_preds(file->filter, entry))) {
1500 __trace_event_discard_commit(buffer, event);
1501 return true;
1502 }
1503
1504 return false;
1505}
1506
1507/**
1508 * event_trigger_unlock_commit - handle triggers and finish event commit
1509 * @file: The file pointer assoctiated to the event
1510 * @buffer: The ring buffer that the event is being written to
1511 * @event: The event meta data in the ring buffer
1512 * @entry: The event itself
1513 * @irq_flags: The state of the interrupts at the start of the event
1514 * @pc: The state of the preempt count at the start of the event.
1515 *
1516 * This is a helper function to handle triggers that require data
1517 * from the event itself. It also tests the event against filters and
1518 * if the event is soft disabled and should be discarded.
1519 */
1520static inline void
1521event_trigger_unlock_commit(struct trace_event_file *file,
1522 struct trace_buffer *buffer,
1523 struct ring_buffer_event *event,
1524 void *entry, unsigned long irq_flags, int pc)
1525{
1526 enum event_trigger_type tt = ETT_NONE;
1527
1528 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1529 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
1530
1531 if (tt)
1532 event_triggers_post_call(file, tt);
1533}
1534
1535/**
1536 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
1537 * @file: The file pointer assoctiated to the event
1538 * @buffer: The ring buffer that the event is being written to
1539 * @event: The event meta data in the ring buffer
1540 * @entry: The event itself
1541 * @irq_flags: The state of the interrupts at the start of the event
1542 * @pc: The state of the preempt count at the start of the event.
1543 *
1544 * This is a helper function to handle triggers that require data
1545 * from the event itself. It also tests the event against filters and
1546 * if the event is soft disabled and should be discarded.
1547 *
1548 * Same as event_trigger_unlock_commit() but calls
1549 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
1550 */
1551static inline void
1552event_trigger_unlock_commit_regs(struct trace_event_file *file,
1553 struct trace_buffer *buffer,
1554 struct ring_buffer_event *event,
1555 void *entry, unsigned long irq_flags, int pc,
1556 struct pt_regs *regs)
1557{
1558 enum event_trigger_type tt = ETT_NONE;
1559
1560 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1561 trace_buffer_unlock_commit_regs(file->tr, buffer, event,
1562 irq_flags, pc, regs);
1563
1564 if (tt)
1565 event_triggers_post_call(file, tt);
1566}
1567
1568#define FILTER_PRED_INVALID ((unsigned short)-1)
1569#define FILTER_PRED_IS_RIGHT (1 << 15)
1570#define FILTER_PRED_FOLD (1 << 15)
1571
1572/*
1573 * The max preds is the size of unsigned short with
1574 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1575 * and FOLD flags. The other is reserved.
1576 *
1577 * 2^14 preds is way more than enough.
1578 */
1579#define MAX_FILTER_PRED 16384
1580
1581struct filter_pred;
1582struct regex;
1583
1584typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1585
1586typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1587
1588enum regex_type {
1589 MATCH_FULL = 0,
1590 MATCH_FRONT_ONLY,
1591 MATCH_MIDDLE_ONLY,
1592 MATCH_END_ONLY,
1593 MATCH_GLOB,
1594 MATCH_INDEX,
1595};
1596
1597struct regex {
1598 char pattern[MAX_FILTER_STR_VAL];
1599 int len;
1600 int field_len;
1601 regex_match_func match;
1602};
1603
1604struct filter_pred {
1605 filter_pred_fn_t fn;
1606 u64 val;
1607 struct regex regex;
1608 unsigned short *ops;
1609 struct ftrace_event_field *field;
1610 int offset;
1611 int not;
1612 int op;
1613};
1614
1615static inline bool is_string_field(struct ftrace_event_field *field)
1616{
1617 return field->filter_type == FILTER_DYN_STRING ||
1618 field->filter_type == FILTER_STATIC_STRING ||
1619 field->filter_type == FILTER_PTR_STRING ||
1620 field->filter_type == FILTER_COMM;
1621}
1622
1623static inline bool is_function_field(struct ftrace_event_field *field)
1624{
1625 return field->filter_type == FILTER_TRACE_FN;
1626}
1627
1628extern enum regex_type
1629filter_parse_regex(char *buff, int len, char **search, int *not);
1630extern void print_event_filter(struct trace_event_file *file,
1631 struct trace_seq *s);
1632extern int apply_event_filter(struct trace_event_file *file,
1633 char *filter_string);
1634extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1635 char *filter_string);
1636extern void print_subsystem_event_filter(struct event_subsystem *system,
1637 struct trace_seq *s);
1638extern int filter_assign_type(const char *type);
1639extern int create_event_filter(struct trace_array *tr,
1640 struct trace_event_call *call,
1641 char *filter_str, bool set_str,
1642 struct event_filter **filterp);
1643extern void free_event_filter(struct event_filter *filter);
1644
1645struct ftrace_event_field *
1646trace_find_event_field(struct trace_event_call *call, char *name);
1647
1648extern void trace_event_enable_cmd_record(bool enable);
1649extern void trace_event_enable_tgid_record(bool enable);
1650
1651extern int event_trace_init(void);
1652extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1653extern int event_trace_del_tracer(struct trace_array *tr);
1654
1655extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1656 const char *system,
1657 const char *event);
1658extern struct trace_event_file *find_event_file(struct trace_array *tr,
1659 const char *system,
1660 const char *event);
1661
1662static inline void *event_file_data(struct file *filp)
1663{
1664 return READ_ONCE(file_inode(filp)->i_private);
1665}
1666
1667extern struct mutex event_mutex;
1668extern struct list_head ftrace_events;
1669
1670extern const struct file_operations event_trigger_fops;
1671extern const struct file_operations event_hist_fops;
1672extern const struct file_operations event_hist_debug_fops;
1673extern const struct file_operations event_inject_fops;
1674
1675#ifdef CONFIG_HIST_TRIGGERS
1676extern int register_trigger_hist_cmd(void);
1677extern int register_trigger_hist_enable_disable_cmds(void);
1678#else
1679static inline int register_trigger_hist_cmd(void) { return 0; }
1680static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1681#endif
1682
1683extern int register_trigger_cmds(void);
1684extern void clear_event_triggers(struct trace_array *tr);
1685
1686struct event_trigger_data {
1687 unsigned long count;
1688 int ref;
1689 struct event_trigger_ops *ops;
1690 struct event_command *cmd_ops;
1691 struct event_filter __rcu *filter;
1692 char *filter_str;
1693 void *private_data;
1694 bool paused;
1695 bool paused_tmp;
1696 struct list_head list;
1697 char *name;
1698 struct list_head named_list;
1699 struct event_trigger_data *named_data;
1700};
1701
1702/* Avoid typos */
1703#define ENABLE_EVENT_STR "enable_event"
1704#define DISABLE_EVENT_STR "disable_event"
1705#define ENABLE_HIST_STR "enable_hist"
1706#define DISABLE_HIST_STR "disable_hist"
1707
1708struct enable_trigger_data {
1709 struct trace_event_file *file;
1710 bool enable;
1711 bool hist;
1712};
1713
1714extern int event_enable_trigger_print(struct seq_file *m,
1715 struct event_trigger_ops *ops,
1716 struct event_trigger_data *data);
1717extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1718 struct event_trigger_data *data);
1719extern int event_enable_trigger_func(struct event_command *cmd_ops,
1720 struct trace_event_file *file,
1721 char *glob, char *cmd, char *param);
1722extern int event_enable_register_trigger(char *glob,
1723 struct event_trigger_ops *ops,
1724 struct event_trigger_data *data,
1725 struct trace_event_file *file);
1726extern void event_enable_unregister_trigger(char *glob,
1727 struct event_trigger_ops *ops,
1728 struct event_trigger_data *test,
1729 struct trace_event_file *file);
1730extern void trigger_data_free(struct event_trigger_data *data);
1731extern int event_trigger_init(struct event_trigger_ops *ops,
1732 struct event_trigger_data *data);
1733extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1734 int trigger_enable);
1735extern void update_cond_flag(struct trace_event_file *file);
1736extern int set_trigger_filter(char *filter_str,
1737 struct event_trigger_data *trigger_data,
1738 struct trace_event_file *file);
1739extern struct event_trigger_data *find_named_trigger(const char *name);
1740extern bool is_named_trigger(struct event_trigger_data *test);
1741extern int save_named_trigger(const char *name,
1742 struct event_trigger_data *data);
1743extern void del_named_trigger(struct event_trigger_data *data);
1744extern void pause_named_trigger(struct event_trigger_data *data);
1745extern void unpause_named_trigger(struct event_trigger_data *data);
1746extern void set_named_trigger_data(struct event_trigger_data *data,
1747 struct event_trigger_data *named_data);
1748extern struct event_trigger_data *
1749get_named_trigger_data(struct event_trigger_data *data);
1750extern int register_event_command(struct event_command *cmd);
1751extern int unregister_event_command(struct event_command *cmd);
1752extern int register_trigger_hist_enable_disable_cmds(void);
1753
1754/**
1755 * struct event_trigger_ops - callbacks for trace event triggers
1756 *
1757 * The methods in this structure provide per-event trigger hooks for
1758 * various trigger operations.
1759 *
1760 * All the methods below, except for @init() and @free(), must be
1761 * implemented.
1762 *
1763 * @func: The trigger 'probe' function called when the triggering
1764 * event occurs. The data passed into this callback is the data
1765 * that was supplied to the event_command @reg() function that
1766 * registered the trigger (see struct event_command) along with
1767 * the trace record, rec.
1768 *
1769 * @init: An optional initialization function called for the trigger
1770 * when the trigger is registered (via the event_command reg()
1771 * function). This can be used to perform per-trigger
1772 * initialization such as incrementing a per-trigger reference
1773 * count, for instance. This is usually implemented by the
1774 * generic utility function @event_trigger_init() (see
1775 * trace_event_triggers.c).
1776 *
1777 * @free: An optional de-initialization function called for the
1778 * trigger when the trigger is unregistered (via the
1779 * event_command @reg() function). This can be used to perform
1780 * per-trigger de-initialization such as decrementing a
1781 * per-trigger reference count and freeing corresponding trigger
1782 * data, for instance. This is usually implemented by the
1783 * generic utility function @event_trigger_free() (see
1784 * trace_event_triggers.c).
1785 *
1786 * @print: The callback function invoked to have the trigger print
1787 * itself. This is usually implemented by a wrapper function
1788 * that calls the generic utility function @event_trigger_print()
1789 * (see trace_event_triggers.c).
1790 */
1791struct event_trigger_ops {
1792 void (*func)(struct event_trigger_data *data,
1793 void *rec,
1794 struct ring_buffer_event *rbe);
1795 int (*init)(struct event_trigger_ops *ops,
1796 struct event_trigger_data *data);
1797 void (*free)(struct event_trigger_ops *ops,
1798 struct event_trigger_data *data);
1799 int (*print)(struct seq_file *m,
1800 struct event_trigger_ops *ops,
1801 struct event_trigger_data *data);
1802};
1803
1804/**
1805 * struct event_command - callbacks and data members for event commands
1806 *
1807 * Event commands are invoked by users by writing the command name
1808 * into the 'trigger' file associated with a trace event. The
1809 * parameters associated with a specific invocation of an event
1810 * command are used to create an event trigger instance, which is
1811 * added to the list of trigger instances associated with that trace
1812 * event. When the event is hit, the set of triggers associated with
1813 * that event is invoked.
1814 *
1815 * The data members in this structure provide per-event command data
1816 * for various event commands.
1817 *
1818 * All the data members below, except for @post_trigger, must be set
1819 * for each event command.
1820 *
1821 * @name: The unique name that identifies the event command. This is
1822 * the name used when setting triggers via trigger files.
1823 *
1824 * @trigger_type: A unique id that identifies the event command
1825 * 'type'. This value has two purposes, the first to ensure that
1826 * only one trigger of the same type can be set at a given time
1827 * for a particular event e.g. it doesn't make sense to have both
1828 * a traceon and traceoff trigger attached to a single event at
1829 * the same time, so traceon and traceoff have the same type
1830 * though they have different names. The @trigger_type value is
1831 * also used as a bit value for deferring the actual trigger
1832 * action until after the current event is finished. Some
1833 * commands need to do this if they themselves log to the trace
1834 * buffer (see the @post_trigger() member below). @trigger_type
1835 * values are defined by adding new values to the trigger_type
1836 * enum in include/linux/trace_events.h.
1837 *
1838 * @flags: See the enum event_command_flags below.
1839 *
1840 * All the methods below, except for @set_filter() and @unreg_all(),
1841 * must be implemented.
1842 *
1843 * @func: The callback function responsible for parsing and
1844 * registering the trigger written to the 'trigger' file by the
1845 * user. It allocates the trigger instance and registers it with
1846 * the appropriate trace event. It makes use of the other
1847 * event_command callback functions to orchestrate this, and is
1848 * usually implemented by the generic utility function
1849 * @event_trigger_callback() (see trace_event_triggers.c).
1850 *
1851 * @reg: Adds the trigger to the list of triggers associated with the
1852 * event, and enables the event trigger itself, after
1853 * initializing it (via the event_trigger_ops @init() function).
1854 * This is also where commands can use the @trigger_type value to
1855 * make the decision as to whether or not multiple instances of
1856 * the trigger should be allowed. This is usually implemented by
1857 * the generic utility function @register_trigger() (see
1858 * trace_event_triggers.c).
1859 *
1860 * @unreg: Removes the trigger from the list of triggers associated
1861 * with the event, and disables the event trigger itself, after
1862 * initializing it (via the event_trigger_ops @free() function).
1863 * This is usually implemented by the generic utility function
1864 * @unregister_trigger() (see trace_event_triggers.c).
1865 *
1866 * @unreg_all: An optional function called to remove all the triggers
1867 * from the list of triggers associated with the event. Called
1868 * when a trigger file is opened in truncate mode.
1869 *
1870 * @set_filter: An optional function called to parse and set a filter
1871 * for the trigger. If no @set_filter() method is set for the
1872 * event command, filters set by the user for the command will be
1873 * ignored. This is usually implemented by the generic utility
1874 * function @set_trigger_filter() (see trace_event_triggers.c).
1875 *
1876 * @get_trigger_ops: The callback function invoked to retrieve the
1877 * event_trigger_ops implementation associated with the command.
1878 */
1879struct event_command {
1880 struct list_head list;
1881 char *name;
1882 enum event_trigger_type trigger_type;
1883 int flags;
1884 int (*func)(struct event_command *cmd_ops,
1885 struct trace_event_file *file,
1886 char *glob, char *cmd, char *params);
1887 int (*reg)(char *glob,
1888 struct event_trigger_ops *ops,
1889 struct event_trigger_data *data,
1890 struct trace_event_file *file);
1891 void (*unreg)(char *glob,
1892 struct event_trigger_ops *ops,
1893 struct event_trigger_data *data,
1894 struct trace_event_file *file);
1895 void (*unreg_all)(struct trace_event_file *file);
1896 int (*set_filter)(char *filter_str,
1897 struct event_trigger_data *data,
1898 struct trace_event_file *file);
1899 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1900};
1901
1902/**
1903 * enum event_command_flags - flags for struct event_command
1904 *
1905 * @POST_TRIGGER: A flag that says whether or not this command needs
1906 * to have its action delayed until after the current event has
1907 * been closed. Some triggers need to avoid being invoked while
1908 * an event is currently in the process of being logged, since
1909 * the trigger may itself log data into the trace buffer. Thus
1910 * we make sure the current event is committed before invoking
1911 * those triggers. To do that, the trigger invocation is split
1912 * in two - the first part checks the filter using the current
1913 * trace record; if a command has the @post_trigger flag set, it
1914 * sets a bit for itself in the return value, otherwise it
1915 * directly invokes the trigger. Once all commands have been
1916 * either invoked or set their return flag, the current record is
1917 * either committed or discarded. At that point, if any commands
1918 * have deferred their triggers, those commands are finally
1919 * invoked following the close of the current event. In other
1920 * words, if the event_trigger_ops @func() probe implementation
1921 * itself logs to the trace buffer, this flag should be set,
1922 * otherwise it can be left unspecified.
1923 *
1924 * @NEEDS_REC: A flag that says whether or not this command needs
1925 * access to the trace record in order to perform its function,
1926 * regardless of whether or not it has a filter associated with
1927 * it (filters make a trigger require access to the trace record
1928 * but are not always present).
1929 */
1930enum event_command_flags {
1931 EVENT_CMD_FL_POST_TRIGGER = 1,
1932 EVENT_CMD_FL_NEEDS_REC = 2,
1933};
1934
1935static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1936{
1937 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1938}
1939
1940static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1941{
1942 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1943}
1944
1945extern int trace_event_enable_disable(struct trace_event_file *file,
1946 int enable, int soft_disable);
1947extern int tracing_alloc_snapshot(void);
1948extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1949extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1950
1951extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1952extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1953
1954extern const char *__start___trace_bprintk_fmt[];
1955extern const char *__stop___trace_bprintk_fmt[];
1956
1957extern const char *__start___tracepoint_str[];
1958extern const char *__stop___tracepoint_str[];
1959
1960void trace_printk_control(bool enabled);
1961void trace_printk_start_comm(void);
1962int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1963int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1964
1965/* Used from boot time tracer */
1966extern int trace_set_options(struct trace_array *tr, char *option);
1967extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
1968extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
1969 unsigned long size, int cpu_id);
1970extern int tracing_set_cpumask(struct trace_array *tr,
1971 cpumask_var_t tracing_cpumask_new);
1972
1973
1974#define MAX_EVENT_NAME_LEN 64
1975
1976extern int trace_run_command(const char *buf, int (*createfn)(int, char**));
1977extern ssize_t trace_parse_run_command(struct file *file,
1978 const char __user *buffer, size_t count, loff_t *ppos,
1979 int (*createfn)(int, char**));
1980
1981extern unsigned int err_pos(char *cmd, const char *str);
1982extern void tracing_log_err(struct trace_array *tr,
1983 const char *loc, const char *cmd,
1984 const char **errs, u8 type, u8 pos);
1985
1986/*
1987 * Normal trace_printk() and friends allocates special buffers
1988 * to do the manipulation, as well as saves the print formats
1989 * into sections to display. But the trace infrastructure wants
1990 * to use these without the added overhead at the price of being
1991 * a bit slower (used mainly for warnings, where we don't care
1992 * about performance). The internal_trace_puts() is for such
1993 * a purpose.
1994 */
1995#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1996
1997#undef FTRACE_ENTRY
1998#define FTRACE_ENTRY(call, struct_name, id, tstruct, print) \
1999 extern struct trace_event_call \
2000 __aligned(4) event_##call;
2001#undef FTRACE_ENTRY_DUP
2002#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \
2003 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2004#undef FTRACE_ENTRY_PACKED
2005#define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
2006 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2007
2008#include "trace_entries.h"
2009
2010#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
2011int perf_ftrace_event_register(struct trace_event_call *call,
2012 enum trace_reg type, void *data);
2013#else
2014#define perf_ftrace_event_register NULL
2015#endif
2016
2017#ifdef CONFIG_FTRACE_SYSCALLS
2018void init_ftrace_syscalls(void);
2019const char *get_syscall_name(int syscall);
2020#else
2021static inline void init_ftrace_syscalls(void) { }
2022static inline const char *get_syscall_name(int syscall)
2023{
2024 return NULL;
2025}
2026#endif
2027
2028#ifdef CONFIG_EVENT_TRACING
2029void trace_event_init(void);
2030void trace_event_eval_update(struct trace_eval_map **map, int len);
2031/* Used from boot time tracer */
2032extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
2033extern int trigger_process_regex(struct trace_event_file *file, char *buff);
2034#else
2035static inline void __init trace_event_init(void) { }
2036static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
2037#endif
2038
2039#ifdef CONFIG_TRACER_SNAPSHOT
2040void tracing_snapshot_instance(struct trace_array *tr);
2041int tracing_alloc_snapshot_instance(struct trace_array *tr);
2042#else
2043static inline void tracing_snapshot_instance(struct trace_array *tr) { }
2044static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
2045{
2046 return 0;
2047}
2048#endif
2049
2050#ifdef CONFIG_PREEMPT_TRACER
2051void tracer_preempt_on(unsigned long a0, unsigned long a1);
2052void tracer_preempt_off(unsigned long a0, unsigned long a1);
2053#else
2054static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
2055static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2056#endif
2057#ifdef CONFIG_IRQSOFF_TRACER
2058void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2059void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2060#else
2061static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
2062static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2063#endif
2064
2065extern struct trace_iterator *tracepoint_print_iter;
2066
2067/*
2068 * Reset the state of the trace_iterator so that it can read consumed data.
2069 * Normally, the trace_iterator is used for reading the data when it is not
2070 * consumed, and must retain state.
2071 */
2072static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2073{
2074 const size_t offset = offsetof(struct trace_iterator, seq);
2075
2076 /*
2077 * Keep gcc from complaining about overwriting more than just one
2078 * member in the structure.
2079 */
2080 memset((char *)iter + offset, 0, sizeof(struct trace_iterator) - offset);
2081
2082 iter->pos = -1;
2083}
2084
2085#endif /* _LINUX_KERNEL_TRACE_H */