1 // SPDX-License-Identifier: GPL-2.0
2
3 #ifndef _LINUX_KERNEL_TRACE_H
4 #define _LINUX_KERNEL_TRACE_H
5
6 #include <linux/fs.h>
7 #include <linux/atomic.h>
8 #include <linux/sched.h>
9 #include <linux/clocksource.h>
10 #include <linux/ring_buffer.h>
11 #include <linux/mmiotrace.h>
12 #include <linux/tracepoint.h>
13 #include <linux/ftrace.h>
14 #include <linux/trace.h>
15 #include <linux/hw_breakpoint.h>
16 #include <linux/trace_seq.h>
17 #include <linux/trace_events.h>
18 #include <linux/compiler.h>
19 #include <linux/glob.h>
20 #include <linux/irq_work.h>
21 #include <linux/workqueue.h>
22 #include <linux/ctype.h>
23 #include <linux/once_lite.h>
24
25 #include "pid_list.h"
26
27 #ifdef CONFIG_FTRACE_SYSCALLS
28 #include <asm/unistd.h> /* For NR_syscalls */
29 #include <asm/syscall.h> /* some archs define it here */
30 #endif
31
32 #define TRACE_MODE_WRITE 0640
33 #define TRACE_MODE_READ 0440
34
35 enum trace_type {
36 __TRACE_FIRST_TYPE = 0,
37
38 TRACE_FN,
39 TRACE_CTX,
40 TRACE_WAKE,
41 TRACE_STACK,
42 TRACE_PRINT,
43 TRACE_BPRINT,
44 TRACE_MMIO_RW,
45 TRACE_MMIO_MAP,
46 TRACE_BRANCH,
47 TRACE_GRAPH_RET,
48 TRACE_GRAPH_ENT,
49 TRACE_USER_STACK,
50 TRACE_BLK,
51 TRACE_BPUTS,
52 TRACE_HWLAT,
53 TRACE_OSNOISE,
54 TRACE_TIMERLAT,
55 TRACE_RAW_DATA,
56 TRACE_FUNC_REPEATS,
57
58 __TRACE_LAST_TYPE,
59 };
60
61
62 #undef __field
63 #define __field(type, item) type item;
64
65 #undef __field_fn
66 #define __field_fn(type, item) type item;
67
68 #undef __field_struct
69 #define __field_struct(type, item) __field(type, item)
70
71 #undef __field_desc
72 #define __field_desc(type, container, item)
73
74 #undef __field_packed
75 #define __field_packed(type, container, item)
76
77 #undef __array
78 #define __array(type, item, size) type item[size];
79
80 /*
81 * For backward compatibility, older user space expects to see the
82 * kernel_stack event with a fixed size caller field. But today the fix
83 * size is ignored by the kernel, and the real structure is dynamic.
84 * Expose to user space: "unsigned long caller[8];" but the real structure
85 * will be "unsigned long caller[] __counted_by(size)"
86 */
87 #undef __stack_array
88 #define __stack_array(type, item, size, field) type item[] __counted_by(field);
89
90 #undef __array_desc
91 #define __array_desc(type, container, item, size)
92
93 #undef __dynamic_array
94 #define __dynamic_array(type, item) type item[];
95
96 #undef __rel_dynamic_array
97 #define __rel_dynamic_array(type, item) type item[];
98
99 #undef F_STRUCT
100 #define F_STRUCT(args...) args
101
102 #undef FTRACE_ENTRY
103 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
104 struct struct_name { \
105 struct trace_entry ent; \
106 tstruct \
107 }
108
109 #undef FTRACE_ENTRY_DUP
110 #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
111
112 #undef FTRACE_ENTRY_REG
113 #define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, regfn) \
114 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
115
116 #undef FTRACE_ENTRY_PACKED
117 #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print) \
118 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed
119
120 #include "trace_entries.h"
121
122 /* Use this for memory failure errors */
123 #define MEM_FAIL(condition, fmt, ...) \
124 DO_ONCE_LITE_IF(condition, pr_err, "ERROR: " fmt, ##__VA_ARGS__)
125
126 #define FAULT_STRING "(fault)"
127
128 #define HIST_STACKTRACE_DEPTH 16
129 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long))
130 #define HIST_STACKTRACE_SKIP 5
131
132 /*
133 * syscalls are special, and need special handling, this is why
134 * they are not included in trace_entries.h
135 */
136 struct syscall_trace_enter {
137 struct trace_entry ent;
138 int nr;
139 unsigned long args[];
140 };
141
142 struct syscall_trace_exit {
143 struct trace_entry ent;
144 int nr;
145 long ret;
146 };
147
148 struct kprobe_trace_entry_head {
149 struct trace_entry ent;
150 unsigned long ip;
151 };
152
153 struct eprobe_trace_entry_head {
154 struct trace_entry ent;
155 };
156
157 struct kretprobe_trace_entry_head {
158 struct trace_entry ent;
159 unsigned long func;
160 unsigned long ret_ip;
161 };
162
163 struct fentry_trace_entry_head {
164 struct trace_entry ent;
165 unsigned long ip;
166 };
167
168 struct fexit_trace_entry_head {
169 struct trace_entry ent;
170 unsigned long func;
171 unsigned long ret_ip;
172 };
173
174 #define TRACE_BUF_SIZE 1024
175
176 struct trace_array;
177
178 /*
179 * The CPU trace array - it consists of thousands of trace entries
180 * plus some other descriptor data: (for example which task started
181 * the trace, etc.)
182 */
183 struct trace_array_cpu {
184 atomic_t disabled;
185 void *buffer_page; /* ring buffer spare */
186
187 unsigned long entries;
188 unsigned long saved_latency;
189 unsigned long critical_start;
190 unsigned long critical_end;
191 unsigned long critical_sequence;
192 unsigned long nice;
193 unsigned long policy;
194 unsigned long rt_priority;
195 unsigned long skipped_entries;
196 u64 preempt_timestamp;
197 pid_t pid;
198 kuid_t uid;
199 char comm[TASK_COMM_LEN];
200
201 #ifdef CONFIG_FUNCTION_TRACER
202 int ftrace_ignore_pid;
203 #endif
204 bool ignore_pid;
205 };
206
207 struct tracer;
208 struct trace_option_dentry;
209
210 struct array_buffer {
211 struct trace_array *tr;
212 struct trace_buffer *buffer;
213 struct trace_array_cpu __percpu *data;
214 u64 time_start;
215 int cpu;
216 };
217
218 #define TRACE_FLAGS_MAX_SIZE 32
219
220 struct trace_options {
221 struct tracer *tracer;
222 struct trace_option_dentry *topts;
223 };
224
225 struct trace_pid_list *trace_pid_list_alloc(void);
226 void trace_pid_list_free(struct trace_pid_list *pid_list);
227 bool trace_pid_list_is_set(struct trace_pid_list *pid_list, unsigned int pid);
228 int trace_pid_list_set(struct trace_pid_list *pid_list, unsigned int pid);
229 int trace_pid_list_clear(struct trace_pid_list *pid_list, unsigned int pid);
230 int trace_pid_list_first(struct trace_pid_list *pid_list, unsigned int *pid);
231 int trace_pid_list_next(struct trace_pid_list *pid_list, unsigned int pid,
232 unsigned int *next);
233
234 enum {
235 TRACE_PIDS = BIT(0),
236 TRACE_NO_PIDS = BIT(1),
237 };
238
pid_type_enabled(int type,struct trace_pid_list * pid_list,struct trace_pid_list * no_pid_list)239 static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
240 struct trace_pid_list *no_pid_list)
241 {
242 /* Return true if the pid list in type has pids */
243 return ((type & TRACE_PIDS) && pid_list) ||
244 ((type & TRACE_NO_PIDS) && no_pid_list);
245 }
246
still_need_pid_events(int type,struct trace_pid_list * pid_list,struct trace_pid_list * no_pid_list)247 static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
248 struct trace_pid_list *no_pid_list)
249 {
250 /*
251 * Turning off what is in @type, return true if the "other"
252 * pid list, still has pids in it.
253 */
254 return (!(type & TRACE_PIDS) && pid_list) ||
255 (!(type & TRACE_NO_PIDS) && no_pid_list);
256 }
257
258 typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
259
260 /**
261 * struct cond_snapshot - conditional snapshot data and callback
262 *
263 * The cond_snapshot structure encapsulates a callback function and
264 * data associated with the snapshot for a given tracing instance.
265 *
266 * When a snapshot is taken conditionally, by invoking
267 * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
268 * passed in turn to the cond_snapshot.update() function. That data
269 * can be compared by the update() implementation with the cond_data
270 * contained within the struct cond_snapshot instance associated with
271 * the trace_array. Because the tr->max_lock is held throughout the
272 * update() call, the update() function can directly retrieve the
273 * cond_snapshot and cond_data associated with the per-instance
274 * snapshot associated with the trace_array.
275 *
276 * The cond_snapshot.update() implementation can save data to be
277 * associated with the snapshot if it decides to, and returns 'true'
278 * in that case, or it returns 'false' if the conditional snapshot
279 * shouldn't be taken.
280 *
281 * The cond_snapshot instance is created and associated with the
282 * user-defined cond_data by tracing_cond_snapshot_enable().
283 * Likewise, the cond_snapshot instance is destroyed and is no longer
284 * associated with the trace instance by
285 * tracing_cond_snapshot_disable().
286 *
287 * The method below is required.
288 *
289 * @update: When a conditional snapshot is invoked, the update()
290 * callback function is invoked with the tr->max_lock held. The
291 * update() implementation signals whether or not to actually
292 * take the snapshot, by returning 'true' if so, 'false' if no
293 * snapshot should be taken. Because the max_lock is held for
294 * the duration of update(), the implementation is safe to
295 * directly retrieved and save any implementation data it needs
296 * to in association with the snapshot.
297 */
298 struct cond_snapshot {
299 void *cond_data;
300 cond_update_fn_t update;
301 };
302
303 /*
304 * struct trace_func_repeats - used to keep track of the consecutive
305 * (on the same CPU) calls of a single function.
306 */
307 struct trace_func_repeats {
308 unsigned long ip;
309 unsigned long parent_ip;
310 unsigned long count;
311 u64 ts_last_call;
312 };
313
314 /*
315 * The trace array - an array of per-CPU trace arrays. This is the
316 * highest level data structure that individual tracers deal with.
317 * They have on/off state as well:
318 */
319 struct trace_array {
320 struct list_head list;
321 char *name;
322 struct array_buffer array_buffer;
323 #ifdef CONFIG_TRACER_MAX_TRACE
324 /*
325 * The max_buffer is used to snapshot the trace when a maximum
326 * latency is reached, or when the user initiates a snapshot.
327 * Some tracers will use this to store a maximum trace while
328 * it continues examining live traces.
329 *
330 * The buffers for the max_buffer are set up the same as the array_buffer
331 * When a snapshot is taken, the buffer of the max_buffer is swapped
332 * with the buffer of the array_buffer and the buffers are reset for
333 * the array_buffer so the tracing can continue.
334 */
335 struct array_buffer max_buffer;
336 bool allocated_snapshot;
337 spinlock_t snapshot_trigger_lock;
338 unsigned int snapshot;
339 unsigned 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 /* The below is for memory mapped ring buffer */
347 unsigned int mapped;
348 unsigned long range_addr_start;
349 unsigned long range_addr_size;
350 long text_delta;
351 long data_delta;
352
353 struct trace_pid_list __rcu *filtered_pids;
354 struct trace_pid_list __rcu *filtered_no_pids;
355 /*
356 * max_lock is used to protect the swapping of buffers
357 * when taking a max snapshot. The buffers themselves are
358 * protected by per_cpu spinlocks. But the action of the swap
359 * needs its own lock.
360 *
361 * This is defined as a arch_spinlock_t in order to help
362 * with performance when lockdep debugging is enabled.
363 *
364 * It is also used in other places outside the update_max_tr
365 * so it needs to be defined outside of the
366 * CONFIG_TRACER_MAX_TRACE.
367 */
368 arch_spinlock_t max_lock;
369 int buffer_disabled;
370 #ifdef CONFIG_FTRACE_SYSCALLS
371 int sys_refcount_enter;
372 int sys_refcount_exit;
373 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
374 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
375 #endif
376 int stop_count;
377 int clock_id;
378 int nr_topts;
379 bool clear_trace;
380 int buffer_percent;
381 unsigned int n_err_log_entries;
382 struct tracer *current_trace;
383 unsigned int trace_flags;
384 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
385 unsigned int flags;
386 raw_spinlock_t start_lock;
387 const char *system_names;
388 struct list_head err_log;
389 struct dentry *dir;
390 struct dentry *options;
391 struct dentry *percpu_dir;
392 struct eventfs_inode *event_dir;
393 struct trace_options *topts;
394 struct list_head systems;
395 struct list_head events;
396 struct trace_event_file *trace_marker_file;
397 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
398 /* one per_cpu trace_pipe can be opened by only one user */
399 cpumask_var_t pipe_cpumask;
400 int ref;
401 int trace_ref;
402 #ifdef CONFIG_FUNCTION_TRACER
403 struct ftrace_ops *ops;
404 struct trace_pid_list __rcu *function_pids;
405 struct trace_pid_list __rcu *function_no_pids;
406 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
407 struct fgraph_ops *gops;
408 #endif
409 #ifdef CONFIG_DYNAMIC_FTRACE
410 /* All of these are protected by the ftrace_lock */
411 struct list_head func_probes;
412 struct list_head mod_trace;
413 struct list_head mod_notrace;
414 #endif
415 /* function tracing enabled */
416 int function_enabled;
417 #endif
418 int no_filter_buffering_ref;
419 struct list_head hist_vars;
420 #ifdef CONFIG_TRACER_SNAPSHOT
421 struct cond_snapshot *cond_snapshot;
422 #endif
423 struct trace_func_repeats __percpu *last_func_repeats;
424 /*
425 * On boot up, the ring buffer is set to the minimum size, so that
426 * we do not waste memory on systems that are not using tracing.
427 */
428 bool ring_buffer_expanded;
429 };
430
431 enum {
432 TRACE_ARRAY_FL_GLOBAL = BIT(0),
433 TRACE_ARRAY_FL_BOOT = BIT(1),
434 };
435
436 extern struct list_head ftrace_trace_arrays;
437
438 extern struct mutex trace_types_lock;
439
440 extern int trace_array_get(struct trace_array *tr);
441 extern int tracing_check_open_get_tr(struct trace_array *tr);
442 extern struct trace_array *trace_array_find(const char *instance);
443 extern struct trace_array *trace_array_find_get(const char *instance);
444
445 extern u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe);
446 extern int tracing_set_filter_buffering(struct trace_array *tr, bool set);
447 extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);
448
449 extern bool trace_clock_in_ns(struct trace_array *tr);
450
451 /*
452 * The global tracer (top) should be the first trace array added,
453 * but we check the flag anyway.
454 */
top_trace_array(void)455 static inline struct trace_array *top_trace_array(void)
456 {
457 struct trace_array *tr;
458
459 if (list_empty(&ftrace_trace_arrays))
460 return NULL;
461
462 tr = list_entry(ftrace_trace_arrays.prev,
463 typeof(*tr), list);
464 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
465 return tr;
466 }
467
468 #define FTRACE_CMP_TYPE(var, type) \
469 __builtin_types_compatible_p(typeof(var), type *)
470
471 #undef IF_ASSIGN
472 #define IF_ASSIGN(var, entry, etype, id) \
473 if (FTRACE_CMP_TYPE(var, etype)) { \
474 var = (typeof(var))(entry); \
475 WARN_ON(id != 0 && (entry)->type != id); \
476 break; \
477 }
478
479 /* Will cause compile errors if type is not found. */
480 extern void __ftrace_bad_type(void);
481
482 /*
483 * The trace_assign_type is a verifier that the entry type is
484 * the same as the type being assigned. To add new types simply
485 * add a line with the following format:
486 *
487 * IF_ASSIGN(var, ent, type, id);
488 *
489 * Where "type" is the trace type that includes the trace_entry
490 * as the "ent" item. And "id" is the trace identifier that is
491 * used in the trace_type enum.
492 *
493 * If the type can have more than one id, then use zero.
494 */
495 #define trace_assign_type(var, ent) \
496 do { \
497 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
498 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
499 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
500 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
501 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
502 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
503 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
504 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
505 IF_ASSIGN(var, ent, struct osnoise_entry, TRACE_OSNOISE);\
506 IF_ASSIGN(var, ent, struct timerlat_entry, TRACE_TIMERLAT);\
507 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
508 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
509 TRACE_MMIO_RW); \
510 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
511 TRACE_MMIO_MAP); \
512 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
513 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
514 TRACE_GRAPH_ENT); \
515 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
516 TRACE_GRAPH_RET); \
517 IF_ASSIGN(var, ent, struct func_repeats_entry, \
518 TRACE_FUNC_REPEATS); \
519 __ftrace_bad_type(); \
520 } while (0)
521
522 /*
523 * An option specific to a tracer. This is a boolean value.
524 * The bit is the bit index that sets its value on the
525 * flags value in struct tracer_flags.
526 */
527 struct tracer_opt {
528 const char *name; /* Will appear on the trace_options file */
529 u32 bit; /* Mask assigned in val field in tracer_flags */
530 };
531
532 /*
533 * The set of specific options for a tracer. Your tracer
534 * have to set the initial value of the flags val.
535 */
536 struct tracer_flags {
537 u32 val;
538 struct tracer_opt *opts;
539 struct tracer *trace;
540 };
541
542 /* Makes more easy to define a tracer opt */
543 #define TRACER_OPT(s, b) .name = #s, .bit = b
544
545
546 struct trace_option_dentry {
547 struct tracer_opt *opt;
548 struct tracer_flags *flags;
549 struct trace_array *tr;
550 struct dentry *entry;
551 };
552
553 /**
554 * struct tracer - a specific tracer and its callbacks to interact with tracefs
555 * @name: the name chosen to select it on the available_tracers file
556 * @init: called when one switches to this tracer (echo name > current_tracer)
557 * @reset: called when one switches to another tracer
558 * @start: called when tracing is unpaused (echo 1 > tracing_on)
559 * @stop: called when tracing is paused (echo 0 > tracing_on)
560 * @update_thresh: called when tracing_thresh is updated
561 * @open: called when the trace file is opened
562 * @pipe_open: called when the trace_pipe file is opened
563 * @close: called when the trace file is released
564 * @pipe_close: called when the trace_pipe file is released
565 * @read: override the default read callback on trace_pipe
566 * @splice_read: override the default splice_read callback on trace_pipe
567 * @selftest: selftest to run on boot (see trace_selftest.c)
568 * @print_headers: override the first lines that describe your columns
569 * @print_line: callback that prints a trace
570 * @set_flag: signals one of your private flags changed (trace_options file)
571 * @flags: your private flags
572 */
573 struct tracer {
574 const char *name;
575 int (*init)(struct trace_array *tr);
576 void (*reset)(struct trace_array *tr);
577 void (*start)(struct trace_array *tr);
578 void (*stop)(struct trace_array *tr);
579 int (*update_thresh)(struct trace_array *tr);
580 void (*open)(struct trace_iterator *iter);
581 void (*pipe_open)(struct trace_iterator *iter);
582 void (*close)(struct trace_iterator *iter);
583 void (*pipe_close)(struct trace_iterator *iter);
584 ssize_t (*read)(struct trace_iterator *iter,
585 struct file *filp, char __user *ubuf,
586 size_t cnt, loff_t *ppos);
587 ssize_t (*splice_read)(struct trace_iterator *iter,
588 struct file *filp,
589 loff_t *ppos,
590 struct pipe_inode_info *pipe,
591 size_t len,
592 unsigned int flags);
593 #ifdef CONFIG_FTRACE_STARTUP_TEST
594 int (*selftest)(struct tracer *trace,
595 struct trace_array *tr);
596 #endif
597 void (*print_header)(struct seq_file *m);
598 enum print_line_t (*print_line)(struct trace_iterator *iter);
599 /* If you handled the flag setting, return 0 */
600 int (*set_flag)(struct trace_array *tr,
601 u32 old_flags, u32 bit, int set);
602 /* Return 0 if OK with change, else return non-zero */
603 int (*flag_changed)(struct trace_array *tr,
604 u32 mask, int set);
605 struct tracer *next;
606 struct tracer_flags *flags;
607 int enabled;
608 bool print_max;
609 bool allow_instances;
610 #ifdef CONFIG_TRACER_MAX_TRACE
611 bool use_max_tr;
612 #endif
613 /* True if tracer cannot be enabled in kernel param */
614 bool noboot;
615 };
616
617 static inline struct ring_buffer_iter *
trace_buffer_iter(struct trace_iterator * iter,int cpu)618 trace_buffer_iter(struct trace_iterator *iter, int cpu)
619 {
620 return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;
621 }
622
623 int tracer_init(struct tracer *t, struct trace_array *tr);
624 int tracing_is_enabled(void);
625 void tracing_reset_online_cpus(struct array_buffer *buf);
626 void tracing_reset_all_online_cpus(void);
627 void tracing_reset_all_online_cpus_unlocked(void);
628 int tracing_open_generic(struct inode *inode, struct file *filp);
629 int tracing_open_generic_tr(struct inode *inode, struct file *filp);
630 int tracing_release_generic_tr(struct inode *inode, struct file *file);
631 int tracing_open_file_tr(struct inode *inode, struct file *filp);
632 int tracing_release_file_tr(struct inode *inode, struct file *filp);
633 int tracing_single_release_file_tr(struct inode *inode, struct file *filp);
634 bool tracing_is_disabled(void);
635 bool tracer_tracing_is_on(struct trace_array *tr);
636 void tracer_tracing_on(struct trace_array *tr);
637 void tracer_tracing_off(struct trace_array *tr);
638 struct dentry *trace_create_file(const char *name,
639 umode_t mode,
640 struct dentry *parent,
641 void *data,
642 const struct file_operations *fops);
643
644 int tracing_init_dentry(void);
645
646 struct ring_buffer_event;
647
648 struct ring_buffer_event *
649 trace_buffer_lock_reserve(struct trace_buffer *buffer,
650 int type,
651 unsigned long len,
652 unsigned int trace_ctx);
653
654 int ring_buffer_meta_seq_init(struct file *file, struct trace_buffer *buffer, int cpu);
655
656 struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
657 struct trace_array_cpu *data);
658
659 struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
660 int *ent_cpu, u64 *ent_ts);
661
662 void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,
663 struct ring_buffer_event *event);
664
665 bool trace_is_tracepoint_string(const char *str);
666 const char *trace_event_format(struct trace_iterator *iter, const char *fmt);
667 void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
668 va_list ap) __printf(2, 0);
669 char *trace_iter_expand_format(struct trace_iterator *iter);
670
671 int trace_empty(struct trace_iterator *iter);
672
673 void *trace_find_next_entry_inc(struct trace_iterator *iter);
674
675 void trace_init_global_iter(struct trace_iterator *iter);
676
677 void tracing_iter_reset(struct trace_iterator *iter, int cpu);
678
679 unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
680 unsigned long trace_total_entries(struct trace_array *tr);
681
682 void trace_function(struct trace_array *tr,
683 unsigned long ip,
684 unsigned long parent_ip,
685 unsigned int trace_ctx);
686 void trace_graph_function(struct trace_array *tr,
687 unsigned long ip,
688 unsigned long parent_ip,
689 unsigned int trace_ctx);
690 void trace_latency_header(struct seq_file *m);
691 void trace_default_header(struct seq_file *m);
692 void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
693
694 void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops);
695 int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops);
696
697 void tracing_start_cmdline_record(void);
698 void tracing_stop_cmdline_record(void);
699 void tracing_start_tgid_record(void);
700 void tracing_stop_tgid_record(void);
701
702 int register_tracer(struct tracer *type);
703 int is_tracing_stopped(void);
704
705 loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
706
707 extern cpumask_var_t __read_mostly tracing_buffer_mask;
708
709 #define for_each_tracing_cpu(cpu) \
710 for_each_cpu(cpu, tracing_buffer_mask)
711
712 extern unsigned long nsecs_to_usecs(unsigned long nsecs);
713
714 extern unsigned long tracing_thresh;
715
716 /* PID filtering */
717
718 extern int pid_max;
719
720 bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
721 pid_t search_pid);
722 bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
723 struct trace_pid_list *filtered_no_pids,
724 struct task_struct *task);
725 void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
726 struct task_struct *self,
727 struct task_struct *task);
728 void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
729 void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
730 int trace_pid_show(struct seq_file *m, void *v);
731 int trace_pid_write(struct trace_pid_list *filtered_pids,
732 struct trace_pid_list **new_pid_list,
733 const char __user *ubuf, size_t cnt);
734
735 #ifdef CONFIG_TRACER_MAX_TRACE
736 void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
737 void *cond_data);
738 void update_max_tr_single(struct trace_array *tr,
739 struct task_struct *tsk, int cpu);
740
741 #ifdef CONFIG_FSNOTIFY
742 #define LATENCY_FS_NOTIFY
743 #endif
744 #endif /* CONFIG_TRACER_MAX_TRACE */
745
746 #ifdef LATENCY_FS_NOTIFY
747 void latency_fsnotify(struct trace_array *tr);
748 #else
latency_fsnotify(struct trace_array * tr)749 static inline void latency_fsnotify(struct trace_array *tr) { }
750 #endif
751
752 #ifdef CONFIG_STACKTRACE
753 void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, int skip);
754 #else
__trace_stack(struct trace_array * tr,unsigned int trace_ctx,int skip)755 static inline void __trace_stack(struct trace_array *tr, unsigned int trace_ctx,
756 int skip)
757 {
758 }
759 #endif /* CONFIG_STACKTRACE */
760
761 void trace_last_func_repeats(struct trace_array *tr,
762 struct trace_func_repeats *last_info,
763 unsigned int trace_ctx);
764
765 extern u64 ftrace_now(int cpu);
766
767 extern void trace_find_cmdline(int pid, char comm[]);
768 extern int trace_find_tgid(int pid);
769 extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
770
771 #ifdef CONFIG_DYNAMIC_FTRACE
772 extern unsigned long ftrace_update_tot_cnt;
773 extern unsigned long ftrace_number_of_pages;
774 extern unsigned long ftrace_number_of_groups;
775 void ftrace_init_trace_array(struct trace_array *tr);
776 #else
ftrace_init_trace_array(struct trace_array * tr)777 static inline void ftrace_init_trace_array(struct trace_array *tr) { }
778 #endif
779 #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
780 extern int DYN_FTRACE_TEST_NAME(void);
781 #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
782 extern int DYN_FTRACE_TEST_NAME2(void);
783
784 extern void trace_set_ring_buffer_expanded(struct trace_array *tr);
785 extern bool tracing_selftest_disabled;
786
787 #ifdef CONFIG_FTRACE_STARTUP_TEST
788 extern void __init disable_tracing_selftest(const char *reason);
789
790 extern int trace_selftest_startup_function(struct tracer *trace,
791 struct trace_array *tr);
792 extern int trace_selftest_startup_function_graph(struct tracer *trace,
793 struct trace_array *tr);
794 extern int trace_selftest_startup_irqsoff(struct tracer *trace,
795 struct trace_array *tr);
796 extern int trace_selftest_startup_preemptoff(struct tracer *trace,
797 struct trace_array *tr);
798 extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
799 struct trace_array *tr);
800 extern int trace_selftest_startup_wakeup(struct tracer *trace,
801 struct trace_array *tr);
802 extern int trace_selftest_startup_nop(struct tracer *trace,
803 struct trace_array *tr);
804 extern int trace_selftest_startup_branch(struct tracer *trace,
805 struct trace_array *tr);
806 /*
807 * Tracer data references selftest functions that only occur
808 * on boot up. These can be __init functions. Thus, when selftests
809 * are enabled, then the tracers need to reference __init functions.
810 */
811 #define __tracer_data __refdata
812 #else
disable_tracing_selftest(const char * reason)813 static inline void __init disable_tracing_selftest(const char *reason)
814 {
815 }
816 /* Tracers are seldom changed. Optimize when selftests are disabled. */
817 #define __tracer_data __read_mostly
818 #endif /* CONFIG_FTRACE_STARTUP_TEST */
819
820 extern void *head_page(struct trace_array_cpu *data);
821 extern unsigned long long ns2usecs(u64 nsec);
822 extern int
823 trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
824 extern int
825 trace_vprintk(unsigned long ip, const char *fmt, va_list args);
826 extern int
827 trace_array_vprintk(struct trace_array *tr,
828 unsigned long ip, const char *fmt, va_list args);
829 int trace_array_printk_buf(struct trace_buffer *buffer,
830 unsigned long ip, const char *fmt, ...);
831 void trace_printk_seq(struct trace_seq *s);
832 enum print_line_t print_trace_line(struct trace_iterator *iter);
833
834 extern char trace_find_mark(unsigned long long duration);
835
836 struct ftrace_hash;
837
838 struct ftrace_mod_load {
839 struct list_head list;
840 char *func;
841 char *module;
842 int enable;
843 };
844
845 enum {
846 FTRACE_HASH_FL_MOD = (1 << 0),
847 };
848
849 struct ftrace_hash {
850 unsigned long size_bits;
851 struct hlist_head *buckets;
852 unsigned long count;
853 unsigned long flags;
854 struct rcu_head rcu;
855 };
856
857 struct ftrace_func_entry *
858 ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
859
ftrace_hash_empty(struct ftrace_hash * hash)860 static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
861 {
862 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
863 }
864
865 /* Standard output formatting function used for function return traces */
866 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
867
868 /* Flag options */
869 #define TRACE_GRAPH_PRINT_OVERRUN 0x1
870 #define TRACE_GRAPH_PRINT_CPU 0x2
871 #define TRACE_GRAPH_PRINT_OVERHEAD 0x4
872 #define TRACE_GRAPH_PRINT_PROC 0x8
873 #define TRACE_GRAPH_PRINT_DURATION 0x10
874 #define TRACE_GRAPH_PRINT_ABS_TIME 0x20
875 #define TRACE_GRAPH_PRINT_REL_TIME 0x40
876 #define TRACE_GRAPH_PRINT_IRQS 0x80
877 #define TRACE_GRAPH_PRINT_TAIL 0x100
878 #define TRACE_GRAPH_SLEEP_TIME 0x200
879 #define TRACE_GRAPH_GRAPH_TIME 0x400
880 #define TRACE_GRAPH_PRINT_RETVAL 0x800
881 #define TRACE_GRAPH_PRINT_RETVAL_HEX 0x1000
882 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28
883 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
884
885 extern void ftrace_graph_sleep_time_control(bool enable);
886
887 #ifdef CONFIG_FUNCTION_PROFILER
888 extern void ftrace_graph_graph_time_control(bool enable);
889 #else
ftrace_graph_graph_time_control(bool enable)890 static inline void ftrace_graph_graph_time_control(bool enable) { }
891 #endif
892
893 extern enum print_line_t
894 print_graph_function_flags(struct trace_iterator *iter, u32 flags);
895 extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
896 extern void
897 trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
898 extern void graph_trace_open(struct trace_iterator *iter);
899 extern void graph_trace_close(struct trace_iterator *iter);
900 extern int __trace_graph_entry(struct trace_array *tr,
901 struct ftrace_graph_ent *trace,
902 unsigned int trace_ctx);
903 extern void __trace_graph_return(struct trace_array *tr,
904 struct ftrace_graph_ret *trace,
905 unsigned int trace_ctx);
906 extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
907 extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops);
908 extern void free_fgraph_ops(struct trace_array *tr);
909
910 enum {
911 TRACE_GRAPH_FL = 1,
912
913 /*
914 * In the very unlikely case that an interrupt came in
915 * at a start of graph tracing, and we want to trace
916 * the function in that interrupt, the depth can be greater
917 * than zero, because of the preempted start of a previous
918 * trace. In an even more unlikely case, depth could be 2
919 * if a softirq interrupted the start of graph tracing,
920 * followed by an interrupt preempting a start of graph
921 * tracing in the softirq, and depth can even be 3
922 * if an NMI came in at the start of an interrupt function
923 * that preempted a softirq start of a function that
924 * preempted normal context!!!! Luckily, it can't be
925 * greater than 3, so the next two bits are a mask
926 * of what the depth is when we set TRACE_GRAPH_FL
927 */
928
929 TRACE_GRAPH_DEPTH_START_BIT,
930 TRACE_GRAPH_DEPTH_END_BIT,
931
932 /*
933 * To implement set_graph_notrace, if this bit is set, we ignore
934 * function graph tracing of called functions, until the return
935 * function is called to clear it.
936 */
937 TRACE_GRAPH_NOTRACE_BIT,
938 };
939
940 #define TRACE_GRAPH_NOTRACE (1 << TRACE_GRAPH_NOTRACE_BIT)
941
ftrace_graph_depth(unsigned long * task_var)942 static inline unsigned long ftrace_graph_depth(unsigned long *task_var)
943 {
944 return (*task_var >> TRACE_GRAPH_DEPTH_START_BIT) & 3;
945 }
946
ftrace_graph_set_depth(unsigned long * task_var,int depth)947 static inline void ftrace_graph_set_depth(unsigned long *task_var, int depth)
948 {
949 *task_var &= ~(3 << TRACE_GRAPH_DEPTH_START_BIT);
950 *task_var |= (depth & 3) << TRACE_GRAPH_DEPTH_START_BIT;
951 }
952
953 #ifdef CONFIG_DYNAMIC_FTRACE
954 extern struct ftrace_hash __rcu *ftrace_graph_hash;
955 extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;
956
957 static inline int
ftrace_graph_addr(unsigned long * task_var,struct ftrace_graph_ent * trace)958 ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
959 {
960 unsigned long addr = trace->func;
961 int ret = 0;
962 struct ftrace_hash *hash;
963
964 preempt_disable_notrace();
965
966 /*
967 * Have to open code "rcu_dereference_sched()" because the
968 * function graph tracer can be called when RCU is not
969 * "watching".
970 * Protected with schedule_on_each_cpu(ftrace_sync)
971 */
972 hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
973
974 if (ftrace_hash_empty(hash)) {
975 ret = 1;
976 goto out;
977 }
978
979 if (ftrace_lookup_ip(hash, addr)) {
980 /*
981 * This needs to be cleared on the return functions
982 * when the depth is zero.
983 */
984 *task_var |= TRACE_GRAPH_FL;
985 ftrace_graph_set_depth(task_var, trace->depth);
986
987 /*
988 * If no irqs are to be traced, but a set_graph_function
989 * is set, and called by an interrupt handler, we still
990 * want to trace it.
991 */
992 if (in_hardirq())
993 trace_recursion_set(TRACE_IRQ_BIT);
994 else
995 trace_recursion_clear(TRACE_IRQ_BIT);
996 ret = 1;
997 }
998
999 out:
1000 preempt_enable_notrace();
1001 return ret;
1002 }
1003
1004 static inline void
ftrace_graph_addr_finish(struct fgraph_ops * gops,struct ftrace_graph_ret * trace)1005 ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1006 {
1007 unsigned long *task_var = fgraph_get_task_var(gops);
1008
1009 if ((*task_var & TRACE_GRAPH_FL) &&
1010 trace->depth == ftrace_graph_depth(task_var))
1011 *task_var &= ~TRACE_GRAPH_FL;
1012 }
1013
ftrace_graph_notrace_addr(unsigned long addr)1014 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1015 {
1016 int ret = 0;
1017 struct ftrace_hash *notrace_hash;
1018
1019 preempt_disable_notrace();
1020
1021 /*
1022 * Have to open code "rcu_dereference_sched()" because the
1023 * function graph tracer can be called when RCU is not
1024 * "watching".
1025 * Protected with schedule_on_each_cpu(ftrace_sync)
1026 */
1027 notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
1028 !preemptible());
1029
1030 if (ftrace_lookup_ip(notrace_hash, addr))
1031 ret = 1;
1032
1033 preempt_enable_notrace();
1034 return ret;
1035 }
1036 #else
ftrace_graph_addr(unsigned long * task_var,struct ftrace_graph_ent * trace)1037 static inline int ftrace_graph_addr(unsigned long *task_var, struct ftrace_graph_ent *trace)
1038 {
1039 return 1;
1040 }
1041
ftrace_graph_notrace_addr(unsigned long addr)1042 static inline int ftrace_graph_notrace_addr(unsigned long addr)
1043 {
1044 return 0;
1045 }
ftrace_graph_addr_finish(struct fgraph_ops * gops,struct ftrace_graph_ret * trace)1046 static inline void ftrace_graph_addr_finish(struct fgraph_ops *gops, struct ftrace_graph_ret *trace)
1047 { }
1048 #endif /* CONFIG_DYNAMIC_FTRACE */
1049
1050 extern unsigned int fgraph_max_depth;
1051
1052 static inline bool
ftrace_graph_ignore_func(struct fgraph_ops * gops,struct ftrace_graph_ent * trace)1053 ftrace_graph_ignore_func(struct fgraph_ops *gops, struct ftrace_graph_ent *trace)
1054 {
1055 unsigned long *task_var = fgraph_get_task_var(gops);
1056
1057 /* trace it when it is-nested-in or is a function enabled. */
1058 return !((*task_var & TRACE_GRAPH_FL) ||
1059 ftrace_graph_addr(task_var, trace)) ||
1060 (trace->depth < 0) ||
1061 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
1062 }
1063
1064 void fgraph_init_ops(struct ftrace_ops *dst_ops,
1065 struct ftrace_ops *src_ops);
1066
1067 #else /* CONFIG_FUNCTION_GRAPH_TRACER */
1068 static inline enum print_line_t
print_graph_function_flags(struct trace_iterator * iter,u32 flags)1069 print_graph_function_flags(struct trace_iterator *iter, u32 flags)
1070 {
1071 return TRACE_TYPE_UNHANDLED;
1072 }
free_fgraph_ops(struct trace_array * tr)1073 static inline void free_fgraph_ops(struct trace_array *tr) { }
1074 /* ftrace_ops may not be defined */
1075 #define init_array_fgraph_ops(tr, ops) do { } while (0)
1076 #define allocate_fgraph_ops(tr, ops) ({ 0; })
1077 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
1078
1079 extern struct list_head ftrace_pids;
1080
1081 #ifdef CONFIG_FUNCTION_TRACER
1082
1083 #define FTRACE_PID_IGNORE -1
1084 #define FTRACE_PID_TRACE -2
1085
1086 struct ftrace_func_command {
1087 struct list_head list;
1088 char *name;
1089 int (*func)(struct trace_array *tr,
1090 struct ftrace_hash *hash,
1091 char *func, char *cmd,
1092 char *params, int enable);
1093 };
1094 extern bool ftrace_filter_param __initdata;
ftrace_trace_task(struct trace_array * tr)1095 static inline int ftrace_trace_task(struct trace_array *tr)
1096 {
1097 return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
1098 FTRACE_PID_IGNORE;
1099 }
1100 extern int ftrace_is_dead(void);
1101 int ftrace_create_function_files(struct trace_array *tr,
1102 struct dentry *parent);
1103 void ftrace_destroy_function_files(struct trace_array *tr);
1104 int ftrace_allocate_ftrace_ops(struct trace_array *tr);
1105 void ftrace_free_ftrace_ops(struct trace_array *tr);
1106 void ftrace_init_global_array_ops(struct trace_array *tr);
1107 void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
1108 void ftrace_reset_array_ops(struct trace_array *tr);
1109 void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
1110 void ftrace_init_tracefs_toplevel(struct trace_array *tr,
1111 struct dentry *d_tracer);
1112 void ftrace_clear_pids(struct trace_array *tr);
1113 int init_function_trace(void);
1114 void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
1115 #else
ftrace_trace_task(struct trace_array * tr)1116 static inline int ftrace_trace_task(struct trace_array *tr)
1117 {
1118 return 1;
1119 }
ftrace_is_dead(void)1120 static inline int ftrace_is_dead(void) { return 0; }
1121 static inline int
ftrace_create_function_files(struct trace_array * tr,struct dentry * parent)1122 ftrace_create_function_files(struct trace_array *tr,
1123 struct dentry *parent)
1124 {
1125 return 0;
1126 }
ftrace_allocate_ftrace_ops(struct trace_array * tr)1127 static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
1128 {
1129 return 0;
1130 }
ftrace_free_ftrace_ops(struct trace_array * tr)1131 static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }
ftrace_destroy_function_files(struct trace_array * tr)1132 static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
1133 static inline __init void
ftrace_init_global_array_ops(struct trace_array * tr)1134 ftrace_init_global_array_ops(struct trace_array *tr) { }
ftrace_reset_array_ops(struct trace_array * tr)1135 static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
ftrace_init_tracefs(struct trace_array * tr,struct dentry * d)1136 static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
ftrace_init_tracefs_toplevel(struct trace_array * tr,struct dentry * d)1137 static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
ftrace_clear_pids(struct trace_array * tr)1138 static inline void ftrace_clear_pids(struct trace_array *tr) { }
init_function_trace(void)1139 static inline int init_function_trace(void) { return 0; }
ftrace_pid_follow_fork(struct trace_array * tr,bool enable)1140 static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
1141 /* ftace_func_t type is not defined, use macro instead of static inline */
1142 #define ftrace_init_array_ops(tr, func) do { } while (0)
1143 #endif /* CONFIG_FUNCTION_TRACER */
1144
1145 #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
1146
1147 struct ftrace_probe_ops {
1148 void (*func)(unsigned long ip,
1149 unsigned long parent_ip,
1150 struct trace_array *tr,
1151 struct ftrace_probe_ops *ops,
1152 void *data);
1153 int (*init)(struct ftrace_probe_ops *ops,
1154 struct trace_array *tr,
1155 unsigned long ip, void *init_data,
1156 void **data);
1157 void (*free)(struct ftrace_probe_ops *ops,
1158 struct trace_array *tr,
1159 unsigned long ip, void *data);
1160 int (*print)(struct seq_file *m,
1161 unsigned long ip,
1162 struct ftrace_probe_ops *ops,
1163 void *data);
1164 };
1165
1166 struct ftrace_func_mapper;
1167 typedef int (*ftrace_mapper_func)(void *data);
1168
1169 struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
1170 void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
1171 unsigned long ip);
1172 int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
1173 unsigned long ip, void *data);
1174 void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
1175 unsigned long ip);
1176 void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1177 ftrace_mapper_func free_func);
1178
1179 extern int
1180 register_ftrace_function_probe(char *glob, struct trace_array *tr,
1181 struct ftrace_probe_ops *ops, void *data);
1182 extern int
1183 unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1184 struct ftrace_probe_ops *ops);
1185 extern void clear_ftrace_function_probes(struct trace_array *tr);
1186
1187 int register_ftrace_command(struct ftrace_func_command *cmd);
1188 int unregister_ftrace_command(struct ftrace_func_command *cmd);
1189
1190 void ftrace_create_filter_files(struct ftrace_ops *ops,
1191 struct dentry *parent);
1192 void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1193
1194 extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
1195 int len, int reset);
1196 extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
1197 int len, int reset);
1198 #else
1199 struct ftrace_func_command;
1200
register_ftrace_command(struct ftrace_func_command * cmd)1201 static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1202 {
1203 return -EINVAL;
1204 }
unregister_ftrace_command(char * cmd_name)1205 static inline __init int unregister_ftrace_command(char *cmd_name)
1206 {
1207 return -EINVAL;
1208 }
clear_ftrace_function_probes(struct trace_array * tr)1209 static inline void clear_ftrace_function_probes(struct trace_array *tr)
1210 {
1211 }
1212
1213 /*
1214 * The ops parameter passed in is usually undefined.
1215 * This must be a macro.
1216 */
1217 #define ftrace_create_filter_files(ops, parent) do { } while (0)
1218 #define ftrace_destroy_filter_files(ops) do { } while (0)
1219 #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1220
1221 bool ftrace_event_is_function(struct trace_event_call *call);
1222
1223 /*
1224 * struct trace_parser - servers for reading the user input separated by spaces
1225 * @cont: set if the input is not complete - no final space char was found
1226 * @buffer: holds the parsed user input
1227 * @idx: user input length
1228 * @size: buffer size
1229 */
1230 struct trace_parser {
1231 bool cont;
1232 char *buffer;
1233 unsigned idx;
1234 unsigned size;
1235 };
1236
trace_parser_loaded(struct trace_parser * parser)1237 static inline bool trace_parser_loaded(struct trace_parser *parser)
1238 {
1239 return (parser->idx != 0);
1240 }
1241
trace_parser_cont(struct trace_parser * parser)1242 static inline bool trace_parser_cont(struct trace_parser *parser)
1243 {
1244 return parser->cont;
1245 }
1246
trace_parser_clear(struct trace_parser * parser)1247 static inline void trace_parser_clear(struct trace_parser *parser)
1248 {
1249 parser->cont = false;
1250 parser->idx = 0;
1251 }
1252
1253 extern int trace_parser_get_init(struct trace_parser *parser, int size);
1254 extern void trace_parser_put(struct trace_parser *parser);
1255 extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1256 size_t cnt, loff_t *ppos);
1257
1258 /*
1259 * Only create function graph options if function graph is configured.
1260 */
1261 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1262 # define FGRAPH_FLAGS \
1263 C(DISPLAY_GRAPH, "display-graph"),
1264 #else
1265 # define FGRAPH_FLAGS
1266 #endif
1267
1268 #ifdef CONFIG_BRANCH_TRACER
1269 # define BRANCH_FLAGS \
1270 C(BRANCH, "branch"),
1271 #else
1272 # define BRANCH_FLAGS
1273 #endif
1274
1275 #ifdef CONFIG_FUNCTION_TRACER
1276 # define FUNCTION_FLAGS \
1277 C(FUNCTION, "function-trace"), \
1278 C(FUNC_FORK, "function-fork"),
1279 # define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1280 #else
1281 # define FUNCTION_FLAGS
1282 # define FUNCTION_DEFAULT_FLAGS 0UL
1283 # define TRACE_ITER_FUNC_FORK 0UL
1284 #endif
1285
1286 #ifdef CONFIG_STACKTRACE
1287 # define STACK_FLAGS \
1288 C(STACKTRACE, "stacktrace"),
1289 #else
1290 # define STACK_FLAGS
1291 #endif
1292
1293 /*
1294 * trace_iterator_flags is an enumeration that defines bit
1295 * positions into trace_flags that controls the output.
1296 *
1297 * NOTE: These bits must match the trace_options array in
1298 * trace.c (this macro guarantees it).
1299 */
1300 #define TRACE_FLAGS \
1301 C(PRINT_PARENT, "print-parent"), \
1302 C(SYM_OFFSET, "sym-offset"), \
1303 C(SYM_ADDR, "sym-addr"), \
1304 C(VERBOSE, "verbose"), \
1305 C(RAW, "raw"), \
1306 C(HEX, "hex"), \
1307 C(BIN, "bin"), \
1308 C(BLOCK, "block"), \
1309 C(FIELDS, "fields"), \
1310 C(PRINTK, "trace_printk"), \
1311 C(ANNOTATE, "annotate"), \
1312 C(USERSTACKTRACE, "userstacktrace"), \
1313 C(SYM_USEROBJ, "sym-userobj"), \
1314 C(PRINTK_MSGONLY, "printk-msg-only"), \
1315 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1316 C(LATENCY_FMT, "latency-format"), \
1317 C(RECORD_CMD, "record-cmd"), \
1318 C(RECORD_TGID, "record-tgid"), \
1319 C(OVERWRITE, "overwrite"), \
1320 C(STOP_ON_FREE, "disable_on_free"), \
1321 C(IRQ_INFO, "irq-info"), \
1322 C(MARKERS, "markers"), \
1323 C(EVENT_FORK, "event-fork"), \
1324 C(TRACE_PRINTK, "trace_printk_dest"), \
1325 C(PAUSE_ON_TRACE, "pause-on-trace"), \
1326 C(HASH_PTR, "hash-ptr"), /* Print hashed pointer */ \
1327 FUNCTION_FLAGS \
1328 FGRAPH_FLAGS \
1329 STACK_FLAGS \
1330 BRANCH_FLAGS
1331
1332 /*
1333 * By defining C, we can make TRACE_FLAGS a list of bit names
1334 * that will define the bits for the flag masks.
1335 */
1336 #undef C
1337 #define C(a, b) TRACE_ITER_##a##_BIT
1338
1339 enum trace_iterator_bits {
1340 TRACE_FLAGS
1341 /* Make sure we don't go more than we have bits for */
1342 TRACE_ITER_LAST_BIT
1343 };
1344
1345 /*
1346 * By redefining C, we can make TRACE_FLAGS a list of masks that
1347 * use the bits as defined above.
1348 */
1349 #undef C
1350 #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1351
1352 enum trace_iterator_flags { TRACE_FLAGS };
1353
1354 /*
1355 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1356 * control the output of kernel symbols.
1357 */
1358 #define TRACE_ITER_SYM_MASK \
1359 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1360
1361 extern struct tracer nop_trace;
1362
1363 #ifdef CONFIG_BRANCH_TRACER
1364 extern int enable_branch_tracing(struct trace_array *tr);
1365 extern void disable_branch_tracing(void);
trace_branch_enable(struct trace_array * tr)1366 static inline int trace_branch_enable(struct trace_array *tr)
1367 {
1368 if (tr->trace_flags & TRACE_ITER_BRANCH)
1369 return enable_branch_tracing(tr);
1370 return 0;
1371 }
trace_branch_disable(void)1372 static inline void trace_branch_disable(void)
1373 {
1374 /* due to races, always disable */
1375 disable_branch_tracing();
1376 }
1377 #else
trace_branch_enable(struct trace_array * tr)1378 static inline int trace_branch_enable(struct trace_array *tr)
1379 {
1380 return 0;
1381 }
trace_branch_disable(void)1382 static inline void trace_branch_disable(void)
1383 {
1384 }
1385 #endif /* CONFIG_BRANCH_TRACER */
1386
1387 /* set ring buffers to default size if not already done so */
1388 int tracing_update_buffers(struct trace_array *tr);
1389
1390 union trace_synth_field {
1391 u8 as_u8;
1392 u16 as_u16;
1393 u32 as_u32;
1394 u64 as_u64;
1395 struct trace_dynamic_info as_dynamic;
1396 };
1397
1398 struct ftrace_event_field {
1399 struct list_head link;
1400 const char *name;
1401 const char *type;
1402 int filter_type;
1403 int offset;
1404 int size;
1405 int is_signed;
1406 int len;
1407 };
1408
1409 struct prog_entry;
1410
1411 struct event_filter {
1412 struct prog_entry __rcu *prog;
1413 char *filter_string;
1414 };
1415
1416 struct event_subsystem {
1417 struct list_head list;
1418 const char *name;
1419 struct event_filter *filter;
1420 int ref_count;
1421 };
1422
1423 struct trace_subsystem_dir {
1424 struct list_head list;
1425 struct event_subsystem *subsystem;
1426 struct trace_array *tr;
1427 struct eventfs_inode *ei;
1428 int ref_count;
1429 int nr_events;
1430 };
1431
1432 extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1433 struct trace_buffer *buffer,
1434 struct ring_buffer_event *event);
1435
1436 void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1437 struct trace_buffer *buffer,
1438 struct ring_buffer_event *event,
1439 unsigned int trcace_ctx,
1440 struct pt_regs *regs);
1441
trace_buffer_unlock_commit(struct trace_array * tr,struct trace_buffer * buffer,struct ring_buffer_event * event,unsigned int trace_ctx)1442 static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1443 struct trace_buffer *buffer,
1444 struct ring_buffer_event *event,
1445 unsigned int trace_ctx)
1446 {
1447 trace_buffer_unlock_commit_regs(tr, buffer, event, trace_ctx, NULL);
1448 }
1449
1450 DECLARE_PER_CPU(bool, trace_taskinfo_save);
1451 int trace_save_cmdline(struct task_struct *tsk);
1452 int trace_create_savedcmd(void);
1453 int trace_alloc_tgid_map(void);
1454 void trace_free_saved_cmdlines_buffer(void);
1455
1456 extern const struct file_operations tracing_saved_cmdlines_fops;
1457 extern const struct file_operations tracing_saved_tgids_fops;
1458 extern const struct file_operations tracing_saved_cmdlines_size_fops;
1459
1460 DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1461 DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1462 void trace_buffered_event_disable(void);
1463 void trace_buffered_event_enable(void);
1464
1465 void early_enable_events(struct trace_array *tr, char *buf, bool disable_first);
1466
1467 static inline void
__trace_event_discard_commit(struct trace_buffer * buffer,struct ring_buffer_event * event)1468 __trace_event_discard_commit(struct trace_buffer *buffer,
1469 struct ring_buffer_event *event)
1470 {
1471 if (this_cpu_read(trace_buffered_event) == event) {
1472 /* Simply release the temp buffer and enable preemption */
1473 this_cpu_dec(trace_buffered_event_cnt);
1474 preempt_enable_notrace();
1475 return;
1476 }
1477 /* ring_buffer_discard_commit() enables preemption */
1478 ring_buffer_discard_commit(buffer, event);
1479 }
1480
1481 /*
1482 * Helper function for event_trigger_unlock_commit{_regs}().
1483 * If there are event triggers attached to this event that requires
1484 * filtering against its fields, then they will be called as the
1485 * entry already holds the field information of the current event.
1486 *
1487 * It also checks if the event should be discarded or not.
1488 * It is to be discarded if the event is soft disabled and the
1489 * event was only recorded to process triggers, or if the event
1490 * filter is active and this event did not match the filters.
1491 *
1492 * Returns true if the event is discarded, false otherwise.
1493 */
1494 static inline bool
__event_trigger_test_discard(struct trace_event_file * file,struct trace_buffer * buffer,struct ring_buffer_event * event,void * entry,enum event_trigger_type * tt)1495 __event_trigger_test_discard(struct trace_event_file *file,
1496 struct trace_buffer *buffer,
1497 struct ring_buffer_event *event,
1498 void *entry,
1499 enum event_trigger_type *tt)
1500 {
1501 unsigned long eflags = file->flags;
1502
1503 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1504 *tt = event_triggers_call(file, buffer, entry, event);
1505
1506 if (likely(!(file->flags & (EVENT_FILE_FL_SOFT_DISABLED |
1507 EVENT_FILE_FL_FILTERED |
1508 EVENT_FILE_FL_PID_FILTER))))
1509 return false;
1510
1511 if (file->flags & EVENT_FILE_FL_SOFT_DISABLED)
1512 goto discard;
1513
1514 if (file->flags & EVENT_FILE_FL_FILTERED &&
1515 !filter_match_preds(file->filter, entry))
1516 goto discard;
1517
1518 if ((file->flags & EVENT_FILE_FL_PID_FILTER) &&
1519 trace_event_ignore_this_pid(file))
1520 goto discard;
1521
1522 return false;
1523 discard:
1524 __trace_event_discard_commit(buffer, event);
1525 return true;
1526 }
1527
1528 /**
1529 * event_trigger_unlock_commit - handle triggers and finish event commit
1530 * @file: The file pointer associated with the event
1531 * @buffer: The ring buffer that the event is being written to
1532 * @event: The event meta data in the ring buffer
1533 * @entry: The event itself
1534 * @trace_ctx: The tracing context flags.
1535 *
1536 * This is a helper function to handle triggers that require data
1537 * from the event itself. It also tests the event against filters and
1538 * if the event is soft disabled and should be discarded.
1539 */
1540 static inline void
event_trigger_unlock_commit(struct trace_event_file * file,struct trace_buffer * buffer,struct ring_buffer_event * event,void * entry,unsigned int trace_ctx)1541 event_trigger_unlock_commit(struct trace_event_file *file,
1542 struct trace_buffer *buffer,
1543 struct ring_buffer_event *event,
1544 void *entry, unsigned int trace_ctx)
1545 {
1546 enum event_trigger_type tt = ETT_NONE;
1547
1548 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1549 trace_buffer_unlock_commit(file->tr, buffer, event, trace_ctx);
1550
1551 if (tt)
1552 event_triggers_post_call(file, tt);
1553 }
1554
1555 #define FILTER_PRED_INVALID ((unsigned short)-1)
1556 #define FILTER_PRED_IS_RIGHT (1 << 15)
1557 #define FILTER_PRED_FOLD (1 << 15)
1558
1559 /*
1560 * The max preds is the size of unsigned short with
1561 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1562 * and FOLD flags. The other is reserved.
1563 *
1564 * 2^14 preds is way more than enough.
1565 */
1566 #define MAX_FILTER_PRED 16384
1567
1568 struct filter_pred;
1569 struct regex;
1570
1571 typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1572
1573 enum regex_type {
1574 MATCH_FULL = 0,
1575 MATCH_FRONT_ONLY,
1576 MATCH_MIDDLE_ONLY,
1577 MATCH_END_ONLY,
1578 MATCH_GLOB,
1579 MATCH_INDEX,
1580 };
1581
1582 struct regex {
1583 char pattern[MAX_FILTER_STR_VAL];
1584 int len;
1585 int field_len;
1586 regex_match_func match;
1587 };
1588
is_string_field(struct ftrace_event_field * field)1589 static inline bool is_string_field(struct ftrace_event_field *field)
1590 {
1591 return field->filter_type == FILTER_DYN_STRING ||
1592 field->filter_type == FILTER_RDYN_STRING ||
1593 field->filter_type == FILTER_STATIC_STRING ||
1594 field->filter_type == FILTER_PTR_STRING ||
1595 field->filter_type == FILTER_COMM;
1596 }
1597
is_function_field(struct ftrace_event_field * field)1598 static inline bool is_function_field(struct ftrace_event_field *field)
1599 {
1600 return field->filter_type == FILTER_TRACE_FN;
1601 }
1602
1603 extern enum regex_type
1604 filter_parse_regex(char *buff, int len, char **search, int *not);
1605 extern void print_event_filter(struct trace_event_file *file,
1606 struct trace_seq *s);
1607 extern int apply_event_filter(struct trace_event_file *file,
1608 char *filter_string);
1609 extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1610 char *filter_string);
1611 extern void print_subsystem_event_filter(struct event_subsystem *system,
1612 struct trace_seq *s);
1613 extern int filter_assign_type(const char *type);
1614 extern int create_event_filter(struct trace_array *tr,
1615 struct trace_event_call *call,
1616 char *filter_str, bool set_str,
1617 struct event_filter **filterp);
1618 extern void free_event_filter(struct event_filter *filter);
1619
1620 struct ftrace_event_field *
1621 trace_find_event_field(struct trace_event_call *call, char *name);
1622
1623 extern void trace_event_enable_cmd_record(bool enable);
1624 extern void trace_event_enable_tgid_record(bool enable);
1625
1626 extern int event_trace_init(void);
1627 extern int init_events(void);
1628 extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1629 extern int event_trace_del_tracer(struct trace_array *tr);
1630 extern void __trace_early_add_events(struct trace_array *tr);
1631
1632 extern struct trace_event_file *__find_event_file(struct trace_array *tr,
1633 const char *system,
1634 const char *event);
1635 extern struct trace_event_file *find_event_file(struct trace_array *tr,
1636 const char *system,
1637 const char *event);
1638
event_file_data(struct file * filp)1639 static inline void *event_file_data(struct file *filp)
1640 {
1641 return READ_ONCE(file_inode(filp)->i_private);
1642 }
1643
1644 extern struct mutex event_mutex;
1645 extern struct list_head ftrace_events;
1646
1647 /*
1648 * When the trace_event_file is the filp->i_private pointer,
1649 * it must be taken under the event_mutex lock, and then checked
1650 * if the EVENT_FILE_FL_FREED flag is set. If it is, then the
1651 * data pointed to by the trace_event_file can not be trusted.
1652 *
1653 * Use the event_file_file() to access the trace_event_file from
1654 * the filp the first time under the event_mutex and check for
1655 * NULL. If it is needed to be retrieved again and the event_mutex
1656 * is still held, then the event_file_data() can be used and it
1657 * is guaranteed to be valid.
1658 */
event_file_file(struct file * filp)1659 static inline struct trace_event_file *event_file_file(struct file *filp)
1660 {
1661 struct trace_event_file *file;
1662
1663 lockdep_assert_held(&event_mutex);
1664 file = READ_ONCE(file_inode(filp)->i_private);
1665 if (!file || file->flags & EVENT_FILE_FL_FREED)
1666 return NULL;
1667 return file;
1668 }
1669
1670 extern const struct file_operations event_trigger_fops;
1671 extern const struct file_operations event_hist_fops;
1672 extern const struct file_operations event_hist_debug_fops;
1673 extern const struct file_operations event_inject_fops;
1674
1675 #ifdef CONFIG_HIST_TRIGGERS
1676 extern int register_trigger_hist_cmd(void);
1677 extern int register_trigger_hist_enable_disable_cmds(void);
1678 #else
register_trigger_hist_cmd(void)1679 static inline int register_trigger_hist_cmd(void) { return 0; }
register_trigger_hist_enable_disable_cmds(void)1680 static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1681 #endif
1682
1683 extern int register_trigger_cmds(void);
1684 extern void clear_event_triggers(struct trace_array *tr);
1685
1686 enum {
1687 EVENT_TRIGGER_FL_PROBE = BIT(0),
1688 };
1689
1690 struct event_trigger_data {
1691 unsigned long count;
1692 int ref;
1693 int flags;
1694 struct event_trigger_ops *ops;
1695 struct event_command *cmd_ops;
1696 struct event_filter __rcu *filter;
1697 char *filter_str;
1698 void *private_data;
1699 bool paused;
1700 bool paused_tmp;
1701 struct list_head list;
1702 char *name;
1703 struct list_head named_list;
1704 struct event_trigger_data *named_data;
1705 };
1706
1707 /* Avoid typos */
1708 #define ENABLE_EVENT_STR "enable_event"
1709 #define DISABLE_EVENT_STR "disable_event"
1710 #define ENABLE_HIST_STR "enable_hist"
1711 #define DISABLE_HIST_STR "disable_hist"
1712
1713 struct enable_trigger_data {
1714 struct trace_event_file *file;
1715 bool enable;
1716 bool hist;
1717 };
1718
1719 extern int event_enable_trigger_print(struct seq_file *m,
1720 struct event_trigger_data *data);
1721 extern void event_enable_trigger_free(struct event_trigger_data *data);
1722 extern int event_enable_trigger_parse(struct event_command *cmd_ops,
1723 struct trace_event_file *file,
1724 char *glob, char *cmd,
1725 char *param_and_filter);
1726 extern int event_enable_register_trigger(char *glob,
1727 struct event_trigger_data *data,
1728 struct trace_event_file *file);
1729 extern void event_enable_unregister_trigger(char *glob,
1730 struct event_trigger_data *test,
1731 struct trace_event_file *file);
1732 extern void trigger_data_free(struct event_trigger_data *data);
1733 extern int event_trigger_init(struct event_trigger_data *data);
1734 extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1735 int trigger_enable);
1736 extern void update_cond_flag(struct trace_event_file *file);
1737 extern int set_trigger_filter(char *filter_str,
1738 struct event_trigger_data *trigger_data,
1739 struct trace_event_file *file);
1740 extern struct event_trigger_data *find_named_trigger(const char *name);
1741 extern bool is_named_trigger(struct event_trigger_data *test);
1742 extern int save_named_trigger(const char *name,
1743 struct event_trigger_data *data);
1744 extern void del_named_trigger(struct event_trigger_data *data);
1745 extern void pause_named_trigger(struct event_trigger_data *data);
1746 extern void unpause_named_trigger(struct event_trigger_data *data);
1747 extern void set_named_trigger_data(struct event_trigger_data *data,
1748 struct event_trigger_data *named_data);
1749 extern struct event_trigger_data *
1750 get_named_trigger_data(struct event_trigger_data *data);
1751 extern int register_event_command(struct event_command *cmd);
1752 extern int unregister_event_command(struct event_command *cmd);
1753 extern int register_trigger_hist_enable_disable_cmds(void);
1754 extern bool event_trigger_check_remove(const char *glob);
1755 extern bool event_trigger_empty_param(const char *param);
1756 extern int event_trigger_separate_filter(char *param_and_filter, char **param,
1757 char **filter, bool param_required);
1758 extern struct event_trigger_data *
1759 event_trigger_alloc(struct event_command *cmd_ops,
1760 char *cmd,
1761 char *param,
1762 void *private_data);
1763 extern int event_trigger_parse_num(char *trigger,
1764 struct event_trigger_data *trigger_data);
1765 extern int event_trigger_set_filter(struct event_command *cmd_ops,
1766 struct trace_event_file *file,
1767 char *param,
1768 struct event_trigger_data *trigger_data);
1769 extern void event_trigger_reset_filter(struct event_command *cmd_ops,
1770 struct event_trigger_data *trigger_data);
1771 extern int event_trigger_register(struct event_command *cmd_ops,
1772 struct trace_event_file *file,
1773 char *glob,
1774 struct event_trigger_data *trigger_data);
1775 extern void event_trigger_unregister(struct event_command *cmd_ops,
1776 struct trace_event_file *file,
1777 char *glob,
1778 struct event_trigger_data *trigger_data);
1779
1780 extern void event_file_get(struct trace_event_file *file);
1781 extern void event_file_put(struct trace_event_file *file);
1782
1783 /**
1784 * struct event_trigger_ops - callbacks for trace event triggers
1785 *
1786 * The methods in this structure provide per-event trigger hooks for
1787 * various trigger operations.
1788 *
1789 * The @init and @free methods are used during trigger setup and
1790 * teardown, typically called from an event_command's @parse()
1791 * function implementation.
1792 *
1793 * The @print method is used to print the trigger spec.
1794 *
1795 * The @trigger method is the function that actually implements the
1796 * trigger and is called in the context of the triggering event
1797 * whenever that event occurs.
1798 *
1799 * All the methods below, except for @init() and @free(), must be
1800 * implemented.
1801 *
1802 * @trigger: The trigger 'probe' function called when the triggering
1803 * event occurs. The data passed into this callback is the data
1804 * that was supplied to the event_command @reg() function that
1805 * registered the trigger (see struct event_command) along with
1806 * the trace record, rec.
1807 *
1808 * @init: An optional initialization function called for the trigger
1809 * when the trigger is registered (via the event_command reg()
1810 * function). This can be used to perform per-trigger
1811 * initialization such as incrementing a per-trigger reference
1812 * count, for instance. This is usually implemented by the
1813 * generic utility function @event_trigger_init() (see
1814 * trace_event_triggers.c).
1815 *
1816 * @free: An optional de-initialization function called for the
1817 * trigger when the trigger is unregistered (via the
1818 * event_command @reg() function). This can be used to perform
1819 * per-trigger de-initialization such as decrementing a
1820 * per-trigger reference count and freeing corresponding trigger
1821 * data, for instance. This is usually implemented by the
1822 * generic utility function @event_trigger_free() (see
1823 * trace_event_triggers.c).
1824 *
1825 * @print: The callback function invoked to have the trigger print
1826 * itself. This is usually implemented by a wrapper function
1827 * that calls the generic utility function @event_trigger_print()
1828 * (see trace_event_triggers.c).
1829 */
1830 struct event_trigger_ops {
1831 void (*trigger)(struct event_trigger_data *data,
1832 struct trace_buffer *buffer,
1833 void *rec,
1834 struct ring_buffer_event *rbe);
1835 int (*init)(struct event_trigger_data *data);
1836 void (*free)(struct event_trigger_data *data);
1837 int (*print)(struct seq_file *m,
1838 struct event_trigger_data *data);
1839 };
1840
1841 /**
1842 * struct event_command - callbacks and data members for event commands
1843 *
1844 * Event commands are invoked by users by writing the command name
1845 * into the 'trigger' file associated with a trace event. The
1846 * parameters associated with a specific invocation of an event
1847 * command are used to create an event trigger instance, which is
1848 * added to the list of trigger instances associated with that trace
1849 * event. When the event is hit, the set of triggers associated with
1850 * that event is invoked.
1851 *
1852 * The data members in this structure provide per-event command data
1853 * for various event commands.
1854 *
1855 * All the data members below, except for @post_trigger, must be set
1856 * for each event command.
1857 *
1858 * @name: The unique name that identifies the event command. This is
1859 * the name used when setting triggers via trigger files.
1860 *
1861 * @trigger_type: A unique id that identifies the event command
1862 * 'type'. This value has two purposes, the first to ensure that
1863 * only one trigger of the same type can be set at a given time
1864 * for a particular event e.g. it doesn't make sense to have both
1865 * a traceon and traceoff trigger attached to a single event at
1866 * the same time, so traceon and traceoff have the same type
1867 * though they have different names. The @trigger_type value is
1868 * also used as a bit value for deferring the actual trigger
1869 * action until after the current event is finished. Some
1870 * commands need to do this if they themselves log to the trace
1871 * buffer (see the @post_trigger() member below). @trigger_type
1872 * values are defined by adding new values to the trigger_type
1873 * enum in include/linux/trace_events.h.
1874 *
1875 * @flags: See the enum event_command_flags below.
1876 *
1877 * All the methods below, except for @set_filter() and @unreg_all(),
1878 * must be implemented.
1879 *
1880 * @parse: The callback function responsible for parsing and
1881 * registering the trigger written to the 'trigger' file by the
1882 * user. It allocates the trigger instance and registers it with
1883 * the appropriate trace event. It makes use of the other
1884 * event_command callback functions to orchestrate this, and is
1885 * usually implemented by the generic utility function
1886 * @event_trigger_callback() (see trace_event_triggers.c).
1887 *
1888 * @reg: Adds the trigger to the list of triggers associated with the
1889 * event, and enables the event trigger itself, after
1890 * initializing it (via the event_trigger_ops @init() function).
1891 * This is also where commands can use the @trigger_type value to
1892 * make the decision as to whether or not multiple instances of
1893 * the trigger should be allowed. This is usually implemented by
1894 * the generic utility function @register_trigger() (see
1895 * trace_event_triggers.c).
1896 *
1897 * @unreg: Removes the trigger from the list of triggers associated
1898 * with the event, and disables the event trigger itself, after
1899 * initializing it (via the event_trigger_ops @free() function).
1900 * This is usually implemented by the generic utility function
1901 * @unregister_trigger() (see trace_event_triggers.c).
1902 *
1903 * @unreg_all: An optional function called to remove all the triggers
1904 * from the list of triggers associated with the event. Called
1905 * when a trigger file is opened in truncate mode.
1906 *
1907 * @set_filter: An optional function called to parse and set a filter
1908 * for the trigger. If no @set_filter() method is set for the
1909 * event command, filters set by the user for the command will be
1910 * ignored. This is usually implemented by the generic utility
1911 * function @set_trigger_filter() (see trace_event_triggers.c).
1912 *
1913 * @get_trigger_ops: The callback function invoked to retrieve the
1914 * event_trigger_ops implementation associated with the command.
1915 * This callback function allows a single event_command to
1916 * support multiple trigger implementations via different sets of
1917 * event_trigger_ops, depending on the value of the @param
1918 * string.
1919 */
1920 struct event_command {
1921 struct list_head list;
1922 char *name;
1923 enum event_trigger_type trigger_type;
1924 int flags;
1925 int (*parse)(struct event_command *cmd_ops,
1926 struct trace_event_file *file,
1927 char *glob, char *cmd,
1928 char *param_and_filter);
1929 int (*reg)(char *glob,
1930 struct event_trigger_data *data,
1931 struct trace_event_file *file);
1932 void (*unreg)(char *glob,
1933 struct event_trigger_data *data,
1934 struct trace_event_file *file);
1935 void (*unreg_all)(struct trace_event_file *file);
1936 int (*set_filter)(char *filter_str,
1937 struct event_trigger_data *data,
1938 struct trace_event_file *file);
1939 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1940 };
1941
1942 /**
1943 * enum event_command_flags - flags for struct event_command
1944 *
1945 * @POST_TRIGGER: A flag that says whether or not this command needs
1946 * to have its action delayed until after the current event has
1947 * been closed. Some triggers need to avoid being invoked while
1948 * an event is currently in the process of being logged, since
1949 * the trigger may itself log data into the trace buffer. Thus
1950 * we make sure the current event is committed before invoking
1951 * those triggers. To do that, the trigger invocation is split
1952 * in two - the first part checks the filter using the current
1953 * trace record; if a command has the @post_trigger flag set, it
1954 * sets a bit for itself in the return value, otherwise it
1955 * directly invokes the trigger. Once all commands have been
1956 * either invoked or set their return flag, the current record is
1957 * either committed or discarded. At that point, if any commands
1958 * have deferred their triggers, those commands are finally
1959 * invoked following the close of the current event. In other
1960 * words, if the event_trigger_ops @func() probe implementation
1961 * itself logs to the trace buffer, this flag should be set,
1962 * otherwise it can be left unspecified.
1963 *
1964 * @NEEDS_REC: A flag that says whether or not this command needs
1965 * access to the trace record in order to perform its function,
1966 * regardless of whether or not it has a filter associated with
1967 * it (filters make a trigger require access to the trace record
1968 * but are not always present).
1969 */
1970 enum event_command_flags {
1971 EVENT_CMD_FL_POST_TRIGGER = 1,
1972 EVENT_CMD_FL_NEEDS_REC = 2,
1973 };
1974
event_command_post_trigger(struct event_command * cmd_ops)1975 static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1976 {
1977 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1978 }
1979
event_command_needs_rec(struct event_command * cmd_ops)1980 static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1981 {
1982 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1983 }
1984
1985 extern int trace_event_enable_disable(struct trace_event_file *file,
1986 int enable, int soft_disable);
1987 extern int tracing_alloc_snapshot(void);
1988 extern void tracing_snapshot_cond(struct trace_array *tr, void *cond_data);
1989 extern int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update);
1990
1991 extern int tracing_snapshot_cond_disable(struct trace_array *tr);
1992 extern void *tracing_cond_snapshot_data(struct trace_array *tr);
1993
1994 extern const char *__start___trace_bprintk_fmt[];
1995 extern const char *__stop___trace_bprintk_fmt[];
1996
1997 extern const char *__start___tracepoint_str[];
1998 extern const char *__stop___tracepoint_str[];
1999
2000 void trace_printk_control(bool enabled);
2001 void trace_printk_start_comm(void);
2002 int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
2003 int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
2004
2005 /* Used from boot time tracer */
2006 extern int trace_set_options(struct trace_array *tr, char *option);
2007 extern int tracing_set_tracer(struct trace_array *tr, const char *buf);
2008 extern ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
2009 unsigned long size, int cpu_id);
2010 extern int tracing_set_cpumask(struct trace_array *tr,
2011 cpumask_var_t tracing_cpumask_new);
2012
2013
2014 #define MAX_EVENT_NAME_LEN 64
2015
2016 extern ssize_t trace_parse_run_command(struct file *file,
2017 const char __user *buffer, size_t count, loff_t *ppos,
2018 int (*createfn)(const char *));
2019
2020 extern unsigned int err_pos(char *cmd, const char *str);
2021 extern void tracing_log_err(struct trace_array *tr,
2022 const char *loc, const char *cmd,
2023 const char **errs, u8 type, u16 pos);
2024
2025 /*
2026 * Normal trace_printk() and friends allocates special buffers
2027 * to do the manipulation, as well as saves the print formats
2028 * into sections to display. But the trace infrastructure wants
2029 * to use these without the added overhead at the price of being
2030 * a bit slower (used mainly for warnings, where we don't care
2031 * about performance). The internal_trace_puts() is for such
2032 * a purpose.
2033 */
2034 #define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
2035
2036 #undef FTRACE_ENTRY
2037 #define FTRACE_ENTRY(call, struct_name, id, tstruct, print) \
2038 extern struct trace_event_call \
2039 __aligned(4) event_##call;
2040 #undef FTRACE_ENTRY_DUP
2041 #define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print) \
2042 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2043 #undef FTRACE_ENTRY_PACKED
2044 #define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print) \
2045 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print))
2046
2047 #include "trace_entries.h"
2048
2049 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
2050 int perf_ftrace_event_register(struct trace_event_call *call,
2051 enum trace_reg type, void *data);
2052 #else
2053 #define perf_ftrace_event_register NULL
2054 #endif
2055
2056 #ifdef CONFIG_FTRACE_SYSCALLS
2057 void init_ftrace_syscalls(void);
2058 const char *get_syscall_name(int syscall);
2059 #else
init_ftrace_syscalls(void)2060 static inline void init_ftrace_syscalls(void) { }
get_syscall_name(int syscall)2061 static inline const char *get_syscall_name(int syscall)
2062 {
2063 return NULL;
2064 }
2065 #endif
2066
2067 #ifdef CONFIG_EVENT_TRACING
2068 void trace_event_init(void);
2069 void trace_event_eval_update(struct trace_eval_map **map, int len);
2070 /* Used from boot time tracer */
2071 extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
2072 extern int trigger_process_regex(struct trace_event_file *file, char *buff);
2073 #else
trace_event_init(void)2074 static inline void __init trace_event_init(void) { }
trace_event_eval_update(struct trace_eval_map ** map,int len)2075 static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
2076 #endif
2077
2078 #ifdef CONFIG_TRACER_SNAPSHOT
2079 void tracing_snapshot_instance(struct trace_array *tr);
2080 int tracing_alloc_snapshot_instance(struct trace_array *tr);
2081 int tracing_arm_snapshot(struct trace_array *tr);
2082 void tracing_disarm_snapshot(struct trace_array *tr);
2083 #else
tracing_snapshot_instance(struct trace_array * tr)2084 static inline void tracing_snapshot_instance(struct trace_array *tr) { }
tracing_alloc_snapshot_instance(struct trace_array * tr)2085 static inline int tracing_alloc_snapshot_instance(struct trace_array *tr)
2086 {
2087 return 0;
2088 }
tracing_arm_snapshot(struct trace_array * tr)2089 static inline int tracing_arm_snapshot(struct trace_array *tr) { return 0; }
tracing_disarm_snapshot(struct trace_array * tr)2090 static inline void tracing_disarm_snapshot(struct trace_array *tr) { }
2091 #endif
2092
2093 #ifdef CONFIG_PREEMPT_TRACER
2094 void tracer_preempt_on(unsigned long a0, unsigned long a1);
2095 void tracer_preempt_off(unsigned long a0, unsigned long a1);
2096 #else
tracer_preempt_on(unsigned long a0,unsigned long a1)2097 static inline void tracer_preempt_on(unsigned long a0, unsigned long a1) { }
tracer_preempt_off(unsigned long a0,unsigned long a1)2098 static inline void tracer_preempt_off(unsigned long a0, unsigned long a1) { }
2099 #endif
2100 #ifdef CONFIG_IRQSOFF_TRACER
2101 void tracer_hardirqs_on(unsigned long a0, unsigned long a1);
2102 void tracer_hardirqs_off(unsigned long a0, unsigned long a1);
2103 #else
tracer_hardirqs_on(unsigned long a0,unsigned long a1)2104 static inline void tracer_hardirqs_on(unsigned long a0, unsigned long a1) { }
tracer_hardirqs_off(unsigned long a0,unsigned long a1)2105 static inline void tracer_hardirqs_off(unsigned long a0, unsigned long a1) { }
2106 #endif
2107
2108 /*
2109 * Reset the state of the trace_iterator so that it can read consumed data.
2110 * Normally, the trace_iterator is used for reading the data when it is not
2111 * consumed, and must retain state.
2112 */
trace_iterator_reset(struct trace_iterator * iter)2113 static __always_inline void trace_iterator_reset(struct trace_iterator *iter)
2114 {
2115 memset_startat(iter, 0, seq);
2116 iter->pos = -1;
2117 }
2118
2119 /* Check the name is good for event/group/fields */
__is_good_name(const char * name,bool hash_ok)2120 static inline bool __is_good_name(const char *name, bool hash_ok)
2121 {
2122 if (!isalpha(*name) && *name != '_' && (!hash_ok || *name != '-'))
2123 return false;
2124 while (*++name != '\0') {
2125 if (!isalpha(*name) && !isdigit(*name) && *name != '_' &&
2126 (!hash_ok || *name != '-'))
2127 return false;
2128 }
2129 return true;
2130 }
2131
2132 /* Check the name is good for event/group/fields */
is_good_name(const char * name)2133 static inline bool is_good_name(const char *name)
2134 {
2135 return __is_good_name(name, false);
2136 }
2137
2138 /* Check the name is good for system */
is_good_system_name(const char * name)2139 static inline bool is_good_system_name(const char *name)
2140 {
2141 return __is_good_name(name, true);
2142 }
2143
2144 /* Convert certain expected symbols into '_' when generating event names */
sanitize_event_name(char * name)2145 static inline void sanitize_event_name(char *name)
2146 {
2147 while (*name++ != '\0')
2148 if (*name == ':' || *name == '.')
2149 *name = '_';
2150 }
2151
2152 /*
2153 * This is a generic way to read and write a u64 value from a file in tracefs.
2154 *
2155 * The value is stored on the variable pointed by *val. The value needs
2156 * to be at least *min and at most *max. The write is protected by an
2157 * existing *lock.
2158 */
2159 struct trace_min_max_param {
2160 struct mutex *lock;
2161 u64 *val;
2162 u64 *min;
2163 u64 *max;
2164 };
2165
2166 #define U64_STR_SIZE 24 /* 20 digits max */
2167
2168 extern const struct file_operations trace_min_max_fops;
2169
2170 #ifdef CONFIG_RV
2171 extern int rv_init_interface(void);
2172 #else
rv_init_interface(void)2173 static inline int rv_init_interface(void)
2174 {
2175 return 0;
2176 }
2177 #endif
2178
2179 #endif /* _LINUX_KERNEL_TRACE_H */
2180