projects/linux·blob v4.14 · refs

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1/* SPDX-License-Identifier: GPL-2.0 */
2
3#ifndef _LINUX_KERNEL_TRACE_H
4#define _LINUX_KERNEL_TRACE_H
5
6#include <linux/fs.h>
7#include <linux/atomic.h>
8#include <linux/sched.h>
9#include <linux/clocksource.h>
10#include <linux/ring_buffer.h>
11#include <linux/mmiotrace.h>
12#include <linux/tracepoint.h>
13#include <linux/ftrace.h>
14#include <linux/hw_breakpoint.h>
15#include <linux/trace_seq.h>
16#include <linux/trace_events.h>
17#include <linux/compiler.h>
18#include <linux/trace_seq.h>
19#include <linux/glob.h>
20
21#ifdef CONFIG_FTRACE_SYSCALLS
22#include <asm/unistd.h> /* For NR_SYSCALLS */
23#include <asm/syscall.h> /* some archs define it here */
24#endif
25
26enum trace_type {
27 __TRACE_FIRST_TYPE = 0,
28
29 TRACE_FN,
30 TRACE_CTX,
31 TRACE_WAKE,
32 TRACE_STACK,
33 TRACE_PRINT,
34 TRACE_BPRINT,
35 TRACE_MMIO_RW,
36 TRACE_MMIO_MAP,
37 TRACE_BRANCH,
38 TRACE_GRAPH_RET,
39 TRACE_GRAPH_ENT,
40 TRACE_USER_STACK,
41 TRACE_BLK,
42 TRACE_BPUTS,
43 TRACE_HWLAT,
44 TRACE_RAW_DATA,
45
46 __TRACE_LAST_TYPE,
47};
48
49
50#undef __field
51#define __field(type, item) type item;
52
53#undef __field_struct
54#define __field_struct(type, item) __field(type, item)
55
56#undef __field_desc
57#define __field_desc(type, container, item)
58
59#undef __array
60#define __array(type, item, size) type item[size];
61
62#undef __array_desc
63#define __array_desc(type, container, item, size)
64
65#undef __dynamic_array
66#define __dynamic_array(type, item) type item[];
67
68#undef F_STRUCT
69#define F_STRUCT(args...) args
70
71#undef FTRACE_ENTRY
72#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \
73 struct struct_name { \
74 struct trace_entry ent; \
75 tstruct \
76 }
77
78#undef FTRACE_ENTRY_DUP
79#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
80
81#undef FTRACE_ENTRY_REG
82#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
83 filter, regfn) \
84 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
85 filter)
86
87#undef FTRACE_ENTRY_PACKED
88#define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print, \
89 filter) \
90 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
91 filter) __packed
92
93#include "trace_entries.h"
94
95/*
96 * syscalls are special, and need special handling, this is why
97 * they are not included in trace_entries.h
98 */
99struct syscall_trace_enter {
100 struct trace_entry ent;
101 int nr;
102 unsigned long args[];
103};
104
105struct syscall_trace_exit {
106 struct trace_entry ent;
107 int nr;
108 long ret;
109};
110
111struct kprobe_trace_entry_head {
112 struct trace_entry ent;
113 unsigned long ip;
114};
115
116struct kretprobe_trace_entry_head {
117 struct trace_entry ent;
118 unsigned long func;
119 unsigned long ret_ip;
120};
121
122/*
123 * trace_flag_type is an enumeration that holds different
124 * states when a trace occurs. These are:
125 * IRQS_OFF - interrupts were disabled
126 * IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
127 * NEED_RESCHED - reschedule is requested
128 * HARDIRQ - inside an interrupt handler
129 * SOFTIRQ - inside a softirq handler
130 */
131enum trace_flag_type {
132 TRACE_FLAG_IRQS_OFF = 0x01,
133 TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
134 TRACE_FLAG_NEED_RESCHED = 0x04,
135 TRACE_FLAG_HARDIRQ = 0x08,
136 TRACE_FLAG_SOFTIRQ = 0x10,
137 TRACE_FLAG_PREEMPT_RESCHED = 0x20,
138 TRACE_FLAG_NMI = 0x40,
139};
140
141#define TRACE_BUF_SIZE 1024
142
143struct trace_array;
144
145/*
146 * The CPU trace array - it consists of thousands of trace entries
147 * plus some other descriptor data: (for example which task started
148 * the trace, etc.)
149 */
150struct trace_array_cpu {
151 atomic_t disabled;
152 void *buffer_page; /* ring buffer spare */
153
154 unsigned long entries;
155 unsigned long saved_latency;
156 unsigned long critical_start;
157 unsigned long critical_end;
158 unsigned long critical_sequence;
159 unsigned long nice;
160 unsigned long policy;
161 unsigned long rt_priority;
162 unsigned long skipped_entries;
163 u64 preempt_timestamp;
164 pid_t pid;
165 kuid_t uid;
166 char comm[TASK_COMM_LEN];
167
168 bool ignore_pid;
169#ifdef CONFIG_FUNCTION_TRACER
170 bool ftrace_ignore_pid;
171#endif
172};
173
174struct tracer;
175struct trace_option_dentry;
176
177struct trace_buffer {
178 struct trace_array *tr;
179 struct ring_buffer *buffer;
180 struct trace_array_cpu __percpu *data;
181 u64 time_start;
182 int cpu;
183};
184
185#define TRACE_FLAGS_MAX_SIZE 32
186
187struct trace_options {
188 struct tracer *tracer;
189 struct trace_option_dentry *topts;
190};
191
192struct trace_pid_list {
193 int pid_max;
194 unsigned long *pids;
195};
196
197/*
198 * The trace array - an array of per-CPU trace arrays. This is the
199 * highest level data structure that individual tracers deal with.
200 * They have on/off state as well:
201 */
202struct trace_array {
203 struct list_head list;
204 char *name;
205 struct trace_buffer trace_buffer;
206#ifdef CONFIG_TRACER_MAX_TRACE
207 /*
208 * The max_buffer is used to snapshot the trace when a maximum
209 * latency is reached, or when the user initiates a snapshot.
210 * Some tracers will use this to store a maximum trace while
211 * it continues examining live traces.
212 *
213 * The buffers for the max_buffer are set up the same as the trace_buffer
214 * When a snapshot is taken, the buffer of the max_buffer is swapped
215 * with the buffer of the trace_buffer and the buffers are reset for
216 * the trace_buffer so the tracing can continue.
217 */
218 struct trace_buffer max_buffer;
219 bool allocated_snapshot;
220#endif
221#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
222 unsigned long max_latency;
223#endif
224 struct trace_pid_list __rcu *filtered_pids;
225 /*
226 * max_lock is used to protect the swapping of buffers
227 * when taking a max snapshot. The buffers themselves are
228 * protected by per_cpu spinlocks. But the action of the swap
229 * needs its own lock.
230 *
231 * This is defined as a arch_spinlock_t in order to help
232 * with performance when lockdep debugging is enabled.
233 *
234 * It is also used in other places outside the update_max_tr
235 * so it needs to be defined outside of the
236 * CONFIG_TRACER_MAX_TRACE.
237 */
238 arch_spinlock_t max_lock;
239 int buffer_disabled;
240#ifdef CONFIG_FTRACE_SYSCALLS
241 int sys_refcount_enter;
242 int sys_refcount_exit;
243 struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
244 struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
245#endif
246 int stop_count;
247 int clock_id;
248 int nr_topts;
249 bool clear_trace;
250 struct tracer *current_trace;
251 unsigned int trace_flags;
252 unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
253 unsigned int flags;
254 raw_spinlock_t start_lock;
255 struct dentry *dir;
256 struct dentry *options;
257 struct dentry *percpu_dir;
258 struct dentry *event_dir;
259 struct trace_options *topts;
260 struct list_head systems;
261 struct list_head events;
262 cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
263 int ref;
264#ifdef CONFIG_FUNCTION_TRACER
265 struct ftrace_ops *ops;
266 struct trace_pid_list __rcu *function_pids;
267#ifdef CONFIG_DYNAMIC_FTRACE
268 /* All of these are protected by the ftrace_lock */
269 struct list_head func_probes;
270 struct list_head mod_trace;
271 struct list_head mod_notrace;
272#endif
273 /* function tracing enabled */
274 int function_enabled;
275#endif
276};
277
278enum {
279 TRACE_ARRAY_FL_GLOBAL = (1 << 0)
280};
281
282extern struct list_head ftrace_trace_arrays;
283
284extern struct mutex trace_types_lock;
285
286extern int trace_array_get(struct trace_array *tr);
287extern void trace_array_put(struct trace_array *tr);
288
289/*
290 * The global tracer (top) should be the first trace array added,
291 * but we check the flag anyway.
292 */
293static inline struct trace_array *top_trace_array(void)
294{
295 struct trace_array *tr;
296
297 if (list_empty(&ftrace_trace_arrays))
298 return NULL;
299
300 tr = list_entry(ftrace_trace_arrays.prev,
301 typeof(*tr), list);
302 WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
303 return tr;
304}
305
306#define FTRACE_CMP_TYPE(var, type) \
307 __builtin_types_compatible_p(typeof(var), type *)
308
309#undef IF_ASSIGN
310#define IF_ASSIGN(var, entry, etype, id) \
311 if (FTRACE_CMP_TYPE(var, etype)) { \
312 var = (typeof(var))(entry); \
313 WARN_ON(id && (entry)->type != id); \
314 break; \
315 }
316
317/* Will cause compile errors if type is not found. */
318extern void __ftrace_bad_type(void);
319
320/*
321 * The trace_assign_type is a verifier that the entry type is
322 * the same as the type being assigned. To add new types simply
323 * add a line with the following format:
324 *
325 * IF_ASSIGN(var, ent, type, id);
326 *
327 * Where "type" is the trace type that includes the trace_entry
328 * as the "ent" item. And "id" is the trace identifier that is
329 * used in the trace_type enum.
330 *
331 * If the type can have more than one id, then use zero.
332 */
333#define trace_assign_type(var, ent) \
334 do { \
335 IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
336 IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
337 IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
338 IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
339 IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
340 IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
341 IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
342 IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
343 IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
344 IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
345 TRACE_MMIO_RW); \
346 IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
347 TRACE_MMIO_MAP); \
348 IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
349 IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
350 TRACE_GRAPH_ENT); \
351 IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
352 TRACE_GRAPH_RET); \
353 __ftrace_bad_type(); \
354 } while (0)
355
356/*
357 * An option specific to a tracer. This is a boolean value.
358 * The bit is the bit index that sets its value on the
359 * flags value in struct tracer_flags.
360 */
361struct tracer_opt {
362 const char *name; /* Will appear on the trace_options file */
363 u32 bit; /* Mask assigned in val field in tracer_flags */
364};
365
366/*
367 * The set of specific options for a tracer. Your tracer
368 * have to set the initial value of the flags val.
369 */
370struct tracer_flags {
371 u32 val;
372 struct tracer_opt *opts;
373 struct tracer *trace;
374};
375
376/* Makes more easy to define a tracer opt */
377#define TRACER_OPT(s, b) .name = #s, .bit = b
378
379
380struct trace_option_dentry {
381 struct tracer_opt *opt;
382 struct tracer_flags *flags;
383 struct trace_array *tr;
384 struct dentry *entry;
385};
386
387/**
388 * struct tracer - a specific tracer and its callbacks to interact with tracefs
389 * @name: the name chosen to select it on the available_tracers file
390 * @init: called when one switches to this tracer (echo name > current_tracer)
391 * @reset: called when one switches to another tracer
392 * @start: called when tracing is unpaused (echo 1 > tracing_on)
393 * @stop: called when tracing is paused (echo 0 > tracing_on)
394 * @update_thresh: called when tracing_thresh is updated
395 * @open: called when the trace file is opened
396 * @pipe_open: called when the trace_pipe file is opened
397 * @close: called when the trace file is released
398 * @pipe_close: called when the trace_pipe file is released
399 * @read: override the default read callback on trace_pipe
400 * @splice_read: override the default splice_read callback on trace_pipe
401 * @selftest: selftest to run on boot (see trace_selftest.c)
402 * @print_headers: override the first lines that describe your columns
403 * @print_line: callback that prints a trace
404 * @set_flag: signals one of your private flags changed (trace_options file)
405 * @flags: your private flags
406 */
407struct tracer {
408 const char *name;
409 int (*init)(struct trace_array *tr);
410 void (*reset)(struct trace_array *tr);
411 void (*start)(struct trace_array *tr);
412 void (*stop)(struct trace_array *tr);
413 int (*update_thresh)(struct trace_array *tr);
414 void (*open)(struct trace_iterator *iter);
415 void (*pipe_open)(struct trace_iterator *iter);
416 void (*close)(struct trace_iterator *iter);
417 void (*pipe_close)(struct trace_iterator *iter);
418 ssize_t (*read)(struct trace_iterator *iter,
419 struct file *filp, char __user *ubuf,
420 size_t cnt, loff_t *ppos);
421 ssize_t (*splice_read)(struct trace_iterator *iter,
422 struct file *filp,
423 loff_t *ppos,
424 struct pipe_inode_info *pipe,
425 size_t len,
426 unsigned int flags);
427#ifdef CONFIG_FTRACE_STARTUP_TEST
428 int (*selftest)(struct tracer *trace,
429 struct trace_array *tr);
430#endif
431 void (*print_header)(struct seq_file *m);
432 enum print_line_t (*print_line)(struct trace_iterator *iter);
433 /* If you handled the flag setting, return 0 */
434 int (*set_flag)(struct trace_array *tr,
435 u32 old_flags, u32 bit, int set);
436 /* Return 0 if OK with change, else return non-zero */
437 int (*flag_changed)(struct trace_array *tr,
438 u32 mask, int set);
439 struct tracer *next;
440 struct tracer_flags *flags;
441 int enabled;
442 int ref;
443 bool print_max;
444 bool allow_instances;
445#ifdef CONFIG_TRACER_MAX_TRACE
446 bool use_max_tr;
447#endif
448 /* True if tracer cannot be enabled in kernel param */
449 bool noboot;
450};
451
452
453/* Only current can touch trace_recursion */
454
455/*
456 * For function tracing recursion:
457 * The order of these bits are important.
458 *
459 * When function tracing occurs, the following steps are made:
460 * If arch does not support a ftrace feature:
461 * call internal function (uses INTERNAL bits) which calls...
462 * If callback is registered to the "global" list, the list
463 * function is called and recursion checks the GLOBAL bits.
464 * then this function calls...
465 * The function callback, which can use the FTRACE bits to
466 * check for recursion.
467 *
468 * Now if the arch does not suppport a feature, and it calls
469 * the global list function which calls the ftrace callback
470 * all three of these steps will do a recursion protection.
471 * There's no reason to do one if the previous caller already
472 * did. The recursion that we are protecting against will
473 * go through the same steps again.
474 *
475 * To prevent the multiple recursion checks, if a recursion
476 * bit is set that is higher than the MAX bit of the current
477 * check, then we know that the check was made by the previous
478 * caller, and we can skip the current check.
479 */
480enum {
481 TRACE_BUFFER_BIT,
482 TRACE_BUFFER_NMI_BIT,
483 TRACE_BUFFER_IRQ_BIT,
484 TRACE_BUFFER_SIRQ_BIT,
485
486 /* Start of function recursion bits */
487 TRACE_FTRACE_BIT,
488 TRACE_FTRACE_NMI_BIT,
489 TRACE_FTRACE_IRQ_BIT,
490 TRACE_FTRACE_SIRQ_BIT,
491
492 /* INTERNAL_BITs must be greater than FTRACE_BITs */
493 TRACE_INTERNAL_BIT,
494 TRACE_INTERNAL_NMI_BIT,
495 TRACE_INTERNAL_IRQ_BIT,
496 TRACE_INTERNAL_SIRQ_BIT,
497
498 TRACE_BRANCH_BIT,
499/*
500 * Abuse of the trace_recursion.
501 * As we need a way to maintain state if we are tracing the function
502 * graph in irq because we want to trace a particular function that
503 * was called in irq context but we have irq tracing off. Since this
504 * can only be modified by current, we can reuse trace_recursion.
505 */
506 TRACE_IRQ_BIT,
507};
508
509#define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
510#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
511#define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit)))
512
513#define TRACE_CONTEXT_BITS 4
514
515#define TRACE_FTRACE_START TRACE_FTRACE_BIT
516#define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
517
518#define TRACE_LIST_START TRACE_INTERNAL_BIT
519#define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
520
521#define TRACE_CONTEXT_MASK TRACE_LIST_MAX
522
523static __always_inline int trace_get_context_bit(void)
524{
525 int bit;
526
527 if (in_interrupt()) {
528 if (in_nmi())
529 bit = 0;
530
531 else if (in_irq())
532 bit = 1;
533 else
534 bit = 2;
535 } else
536 bit = 3;
537
538 return bit;
539}
540
541static __always_inline int trace_test_and_set_recursion(int start, int max)
542{
543 unsigned int val = current->trace_recursion;
544 int bit;
545
546 /* A previous recursion check was made */
547 if ((val & TRACE_CONTEXT_MASK) > max)
548 return 0;
549
550 bit = trace_get_context_bit() + start;
551 if (unlikely(val & (1 << bit)))
552 return -1;
553
554 val |= 1 << bit;
555 current->trace_recursion = val;
556 barrier();
557
558 return bit;
559}
560
561static __always_inline void trace_clear_recursion(int bit)
562{
563 unsigned int val = current->trace_recursion;
564
565 if (!bit)
566 return;
567
568 bit = 1 << bit;
569 val &= ~bit;
570
571 barrier();
572 current->trace_recursion = val;
573}
574
575static inline struct ring_buffer_iter *
576trace_buffer_iter(struct trace_iterator *iter, int cpu)
577{
578 if (iter->buffer_iter && iter->buffer_iter[cpu])
579 return iter->buffer_iter[cpu];
580 return NULL;
581}
582
583int tracer_init(struct tracer *t, struct trace_array *tr);
584int tracing_is_enabled(void);
585void tracing_reset(struct trace_buffer *buf, int cpu);
586void tracing_reset_online_cpus(struct trace_buffer *buf);
587void tracing_reset_current(int cpu);
588void tracing_reset_all_online_cpus(void);
589int tracing_open_generic(struct inode *inode, struct file *filp);
590bool tracing_is_disabled(void);
591int tracer_tracing_is_on(struct trace_array *tr);
592void tracer_tracing_on(struct trace_array *tr);
593void tracer_tracing_off(struct trace_array *tr);
594struct dentry *trace_create_file(const char *name,
595 umode_t mode,
596 struct dentry *parent,
597 void *data,
598 const struct file_operations *fops);
599
600struct dentry *tracing_init_dentry(void);
601
602struct ring_buffer_event;
603
604struct ring_buffer_event *
605trace_buffer_lock_reserve(struct ring_buffer *buffer,
606 int type,
607 unsigned long len,
608 unsigned long flags,
609 int pc);
610
611struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
612 struct trace_array_cpu *data);
613
614struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
615 int *ent_cpu, u64 *ent_ts);
616
617void trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer,
618 struct ring_buffer_event *event);
619
620int trace_empty(struct trace_iterator *iter);
621
622void *trace_find_next_entry_inc(struct trace_iterator *iter);
623
624void trace_init_global_iter(struct trace_iterator *iter);
625
626void tracing_iter_reset(struct trace_iterator *iter, int cpu);
627
628void trace_function(struct trace_array *tr,
629 unsigned long ip,
630 unsigned long parent_ip,
631 unsigned long flags, int pc);
632void trace_graph_function(struct trace_array *tr,
633 unsigned long ip,
634 unsigned long parent_ip,
635 unsigned long flags, int pc);
636void trace_latency_header(struct seq_file *m);
637void trace_default_header(struct seq_file *m);
638void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
639int trace_empty(struct trace_iterator *iter);
640
641void trace_graph_return(struct ftrace_graph_ret *trace);
642int trace_graph_entry(struct ftrace_graph_ent *trace);
643void set_graph_array(struct trace_array *tr);
644
645void tracing_start_cmdline_record(void);
646void tracing_stop_cmdline_record(void);
647void tracing_start_tgid_record(void);
648void tracing_stop_tgid_record(void);
649
650int register_tracer(struct tracer *type);
651int is_tracing_stopped(void);
652
653loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
654
655extern cpumask_var_t __read_mostly tracing_buffer_mask;
656
657#define for_each_tracing_cpu(cpu) \
658 for_each_cpu(cpu, tracing_buffer_mask)
659
660extern unsigned long nsecs_to_usecs(unsigned long nsecs);
661
662extern unsigned long tracing_thresh;
663
664/* PID filtering */
665
666extern int pid_max;
667
668bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
669 pid_t search_pid);
670bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
671 struct task_struct *task);
672void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
673 struct task_struct *self,
674 struct task_struct *task);
675void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
676void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
677int trace_pid_show(struct seq_file *m, void *v);
678void trace_free_pid_list(struct trace_pid_list *pid_list);
679int trace_pid_write(struct trace_pid_list *filtered_pids,
680 struct trace_pid_list **new_pid_list,
681 const char __user *ubuf, size_t cnt);
682
683#ifdef CONFIG_TRACER_MAX_TRACE
684void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
685void update_max_tr_single(struct trace_array *tr,
686 struct task_struct *tsk, int cpu);
687#endif /* CONFIG_TRACER_MAX_TRACE */
688
689#ifdef CONFIG_STACKTRACE
690void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
691 int pc);
692
693void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
694 int pc);
695#else
696static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
697 unsigned long flags, int pc)
698{
699}
700
701static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
702 int skip, int pc)
703{
704}
705#endif /* CONFIG_STACKTRACE */
706
707extern u64 ftrace_now(int cpu);
708
709extern void trace_find_cmdline(int pid, char comm[]);
710extern int trace_find_tgid(int pid);
711extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
712
713#ifdef CONFIG_DYNAMIC_FTRACE
714extern unsigned long ftrace_update_tot_cnt;
715void ftrace_init_trace_array(struct trace_array *tr);
716#else
717static inline void ftrace_init_trace_array(struct trace_array *tr) { }
718#endif
719#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
720extern int DYN_FTRACE_TEST_NAME(void);
721#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
722extern int DYN_FTRACE_TEST_NAME2(void);
723
724extern bool ring_buffer_expanded;
725extern bool tracing_selftest_disabled;
726
727#ifdef CONFIG_FTRACE_STARTUP_TEST
728extern int trace_selftest_startup_function(struct tracer *trace,
729 struct trace_array *tr);
730extern int trace_selftest_startup_function_graph(struct tracer *trace,
731 struct trace_array *tr);
732extern int trace_selftest_startup_irqsoff(struct tracer *trace,
733 struct trace_array *tr);
734extern int trace_selftest_startup_preemptoff(struct tracer *trace,
735 struct trace_array *tr);
736extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
737 struct trace_array *tr);
738extern int trace_selftest_startup_wakeup(struct tracer *trace,
739 struct trace_array *tr);
740extern int trace_selftest_startup_nop(struct tracer *trace,
741 struct trace_array *tr);
742extern int trace_selftest_startup_sched_switch(struct tracer *trace,
743 struct trace_array *tr);
744extern int trace_selftest_startup_branch(struct tracer *trace,
745 struct trace_array *tr);
746/*
747 * Tracer data references selftest functions that only occur
748 * on boot up. These can be __init functions. Thus, when selftests
749 * are enabled, then the tracers need to reference __init functions.
750 */
751#define __tracer_data __refdata
752#else
753/* Tracers are seldom changed. Optimize when selftests are disabled. */
754#define __tracer_data __read_mostly
755#endif /* CONFIG_FTRACE_STARTUP_TEST */
756
757extern void *head_page(struct trace_array_cpu *data);
758extern unsigned long long ns2usecs(u64 nsec);
759extern int
760trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
761extern int
762trace_vprintk(unsigned long ip, const char *fmt, va_list args);
763extern int
764trace_array_vprintk(struct trace_array *tr,
765 unsigned long ip, const char *fmt, va_list args);
766int trace_array_printk(struct trace_array *tr,
767 unsigned long ip, const char *fmt, ...);
768int trace_array_printk_buf(struct ring_buffer *buffer,
769 unsigned long ip, const char *fmt, ...);
770void trace_printk_seq(struct trace_seq *s);
771enum print_line_t print_trace_line(struct trace_iterator *iter);
772
773extern char trace_find_mark(unsigned long long duration);
774
775struct ftrace_hash;
776
777struct ftrace_mod_load {
778 struct list_head list;
779 char *func;
780 char *module;
781 int enable;
782};
783
784enum {
785 FTRACE_HASH_FL_MOD = (1 << 0),
786};
787
788struct ftrace_hash {
789 unsigned long size_bits;
790 struct hlist_head *buckets;
791 unsigned long count;
792 unsigned long flags;
793 struct rcu_head rcu;
794};
795
796struct ftrace_func_entry *
797ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
798
799static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
800{
801 return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
802}
803
804/* Standard output formatting function used for function return traces */
805#ifdef CONFIG_FUNCTION_GRAPH_TRACER
806
807/* Flag options */
808#define TRACE_GRAPH_PRINT_OVERRUN 0x1
809#define TRACE_GRAPH_PRINT_CPU 0x2
810#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
811#define TRACE_GRAPH_PRINT_PROC 0x8
812#define TRACE_GRAPH_PRINT_DURATION 0x10
813#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
814#define TRACE_GRAPH_PRINT_IRQS 0x40
815#define TRACE_GRAPH_PRINT_TAIL 0x80
816#define TRACE_GRAPH_SLEEP_TIME 0x100
817#define TRACE_GRAPH_GRAPH_TIME 0x200
818#define TRACE_GRAPH_PRINT_FILL_SHIFT 28
819#define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
820
821extern void ftrace_graph_sleep_time_control(bool enable);
822extern void ftrace_graph_graph_time_control(bool enable);
823
824extern enum print_line_t
825print_graph_function_flags(struct trace_iterator *iter, u32 flags);
826extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
827extern void
828trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
829extern void graph_trace_open(struct trace_iterator *iter);
830extern void graph_trace_close(struct trace_iterator *iter);
831extern int __trace_graph_entry(struct trace_array *tr,
832 struct ftrace_graph_ent *trace,
833 unsigned long flags, int pc);
834extern void __trace_graph_return(struct trace_array *tr,
835 struct ftrace_graph_ret *trace,
836 unsigned long flags, int pc);
837
838#ifdef CONFIG_DYNAMIC_FTRACE
839extern struct ftrace_hash *ftrace_graph_hash;
840extern struct ftrace_hash *ftrace_graph_notrace_hash;
841
842static inline int ftrace_graph_addr(unsigned long addr)
843{
844 int ret = 0;
845
846 preempt_disable_notrace();
847
848 if (ftrace_hash_empty(ftrace_graph_hash)) {
849 ret = 1;
850 goto out;
851 }
852
853 if (ftrace_lookup_ip(ftrace_graph_hash, addr)) {
854 /*
855 * If no irqs are to be traced, but a set_graph_function
856 * is set, and called by an interrupt handler, we still
857 * want to trace it.
858 */
859 if (in_irq())
860 trace_recursion_set(TRACE_IRQ_BIT);
861 else
862 trace_recursion_clear(TRACE_IRQ_BIT);
863 ret = 1;
864 }
865
866out:
867 preempt_enable_notrace();
868 return ret;
869}
870
871static inline int ftrace_graph_notrace_addr(unsigned long addr)
872{
873 int ret = 0;
874
875 preempt_disable_notrace();
876
877 if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr))
878 ret = 1;
879
880 preempt_enable_notrace();
881 return ret;
882}
883#else
884static inline int ftrace_graph_addr(unsigned long addr)
885{
886 return 1;
887}
888
889static inline int ftrace_graph_notrace_addr(unsigned long addr)
890{
891 return 0;
892}
893#endif /* CONFIG_DYNAMIC_FTRACE */
894
895extern unsigned int fgraph_max_depth;
896
897static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
898{
899 /* trace it when it is-nested-in or is a function enabled. */
900 return !(trace->depth || ftrace_graph_addr(trace->func)) ||
901 (trace->depth < 0) ||
902 (fgraph_max_depth && trace->depth >= fgraph_max_depth);
903}
904
905#else /* CONFIG_FUNCTION_GRAPH_TRACER */
906static inline enum print_line_t
907print_graph_function_flags(struct trace_iterator *iter, u32 flags)
908{
909 return TRACE_TYPE_UNHANDLED;
910}
911#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
912
913extern struct list_head ftrace_pids;
914
915#ifdef CONFIG_FUNCTION_TRACER
916struct ftrace_func_command {
917 struct list_head list;
918 char *name;
919 int (*func)(struct trace_array *tr,
920 struct ftrace_hash *hash,
921 char *func, char *cmd,
922 char *params, int enable);
923};
924extern bool ftrace_filter_param __initdata;
925static inline int ftrace_trace_task(struct trace_array *tr)
926{
927 return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid);
928}
929extern int ftrace_is_dead(void);
930int ftrace_create_function_files(struct trace_array *tr,
931 struct dentry *parent);
932void ftrace_destroy_function_files(struct trace_array *tr);
933void ftrace_init_global_array_ops(struct trace_array *tr);
934void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
935void ftrace_reset_array_ops(struct trace_array *tr);
936int using_ftrace_ops_list_func(void);
937void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
938void ftrace_init_tracefs_toplevel(struct trace_array *tr,
939 struct dentry *d_tracer);
940void ftrace_clear_pids(struct trace_array *tr);
941int init_function_trace(void);
942void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
943#else
944static inline int ftrace_trace_task(struct trace_array *tr)
945{
946 return 1;
947}
948static inline int ftrace_is_dead(void) { return 0; }
949static inline int
950ftrace_create_function_files(struct trace_array *tr,
951 struct dentry *parent)
952{
953 return 0;
954}
955static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
956static inline __init void
957ftrace_init_global_array_ops(struct trace_array *tr) { }
958static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
959static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
960static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
961static inline void ftrace_clear_pids(struct trace_array *tr) { }
962static inline int init_function_trace(void) { return 0; }
963static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
964/* ftace_func_t type is not defined, use macro instead of static inline */
965#define ftrace_init_array_ops(tr, func) do { } while (0)
966#endif /* CONFIG_FUNCTION_TRACER */
967
968#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
969
970struct ftrace_probe_ops {
971 void (*func)(unsigned long ip,
972 unsigned long parent_ip,
973 struct trace_array *tr,
974 struct ftrace_probe_ops *ops,
975 void *data);
976 int (*init)(struct ftrace_probe_ops *ops,
977 struct trace_array *tr,
978 unsigned long ip, void *init_data,
979 void **data);
980 void (*free)(struct ftrace_probe_ops *ops,
981 struct trace_array *tr,
982 unsigned long ip, void *data);
983 int (*print)(struct seq_file *m,
984 unsigned long ip,
985 struct ftrace_probe_ops *ops,
986 void *data);
987};
988
989struct ftrace_func_mapper;
990typedef int (*ftrace_mapper_func)(void *data);
991
992struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
993void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
994 unsigned long ip);
995int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
996 unsigned long ip, void *data);
997void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
998 unsigned long ip);
999void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
1000 ftrace_mapper_func free_func);
1001
1002extern int
1003register_ftrace_function_probe(char *glob, struct trace_array *tr,
1004 struct ftrace_probe_ops *ops, void *data);
1005extern int
1006unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
1007 struct ftrace_probe_ops *ops);
1008extern void clear_ftrace_function_probes(struct trace_array *tr);
1009
1010int register_ftrace_command(struct ftrace_func_command *cmd);
1011int unregister_ftrace_command(struct ftrace_func_command *cmd);
1012
1013void ftrace_create_filter_files(struct ftrace_ops *ops,
1014 struct dentry *parent);
1015void ftrace_destroy_filter_files(struct ftrace_ops *ops);
1016#else
1017struct ftrace_func_command;
1018
1019static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
1020{
1021 return -EINVAL;
1022}
1023static inline __init int unregister_ftrace_command(char *cmd_name)
1024{
1025 return -EINVAL;
1026}
1027static inline void clear_ftrace_function_probes(struct trace_array *tr)
1028{
1029}
1030
1031/*
1032 * The ops parameter passed in is usually undefined.
1033 * This must be a macro.
1034 */
1035#define ftrace_create_filter_files(ops, parent) do { } while (0)
1036#define ftrace_destroy_filter_files(ops) do { } while (0)
1037#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
1038
1039bool ftrace_event_is_function(struct trace_event_call *call);
1040
1041/*
1042 * struct trace_parser - servers for reading the user input separated by spaces
1043 * @cont: set if the input is not complete - no final space char was found
1044 * @buffer: holds the parsed user input
1045 * @idx: user input length
1046 * @size: buffer size
1047 */
1048struct trace_parser {
1049 bool cont;
1050 char *buffer;
1051 unsigned idx;
1052 unsigned size;
1053};
1054
1055static inline bool trace_parser_loaded(struct trace_parser *parser)
1056{
1057 return (parser->idx != 0);
1058}
1059
1060static inline bool trace_parser_cont(struct trace_parser *parser)
1061{
1062 return parser->cont;
1063}
1064
1065static inline void trace_parser_clear(struct trace_parser *parser)
1066{
1067 parser->cont = false;
1068 parser->idx = 0;
1069}
1070
1071extern int trace_parser_get_init(struct trace_parser *parser, int size);
1072extern void trace_parser_put(struct trace_parser *parser);
1073extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
1074 size_t cnt, loff_t *ppos);
1075
1076/*
1077 * Only create function graph options if function graph is configured.
1078 */
1079#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1080# define FGRAPH_FLAGS \
1081 C(DISPLAY_GRAPH, "display-graph"),
1082#else
1083# define FGRAPH_FLAGS
1084#endif
1085
1086#ifdef CONFIG_BRANCH_TRACER
1087# define BRANCH_FLAGS \
1088 C(BRANCH, "branch"),
1089#else
1090# define BRANCH_FLAGS
1091#endif
1092
1093#ifdef CONFIG_FUNCTION_TRACER
1094# define FUNCTION_FLAGS \
1095 C(FUNCTION, "function-trace"), \
1096 C(FUNC_FORK, "function-fork"),
1097# define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
1098#else
1099# define FUNCTION_FLAGS
1100# define FUNCTION_DEFAULT_FLAGS 0UL
1101# define TRACE_ITER_FUNC_FORK 0UL
1102#endif
1103
1104#ifdef CONFIG_STACKTRACE
1105# define STACK_FLAGS \
1106 C(STACKTRACE, "stacktrace"),
1107#else
1108# define STACK_FLAGS
1109#endif
1110
1111/*
1112 * trace_iterator_flags is an enumeration that defines bit
1113 * positions into trace_flags that controls the output.
1114 *
1115 * NOTE: These bits must match the trace_options array in
1116 * trace.c (this macro guarantees it).
1117 */
1118#define TRACE_FLAGS \
1119 C(PRINT_PARENT, "print-parent"), \
1120 C(SYM_OFFSET, "sym-offset"), \
1121 C(SYM_ADDR, "sym-addr"), \
1122 C(VERBOSE, "verbose"), \
1123 C(RAW, "raw"), \
1124 C(HEX, "hex"), \
1125 C(BIN, "bin"), \
1126 C(BLOCK, "block"), \
1127 C(PRINTK, "trace_printk"), \
1128 C(ANNOTATE, "annotate"), \
1129 C(USERSTACKTRACE, "userstacktrace"), \
1130 C(SYM_USEROBJ, "sym-userobj"), \
1131 C(PRINTK_MSGONLY, "printk-msg-only"), \
1132 C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
1133 C(LATENCY_FMT, "latency-format"), \
1134 C(RECORD_CMD, "record-cmd"), \
1135 C(RECORD_TGID, "record-tgid"), \
1136 C(OVERWRITE, "overwrite"), \
1137 C(STOP_ON_FREE, "disable_on_free"), \
1138 C(IRQ_INFO, "irq-info"), \
1139 C(MARKERS, "markers"), \
1140 C(EVENT_FORK, "event-fork"), \
1141 FUNCTION_FLAGS \
1142 FGRAPH_FLAGS \
1143 STACK_FLAGS \
1144 BRANCH_FLAGS
1145
1146/*
1147 * By defining C, we can make TRACE_FLAGS a list of bit names
1148 * that will define the bits for the flag masks.
1149 */
1150#undef C
1151#define C(a, b) TRACE_ITER_##a##_BIT
1152
1153enum trace_iterator_bits {
1154 TRACE_FLAGS
1155 /* Make sure we don't go more than we have bits for */
1156 TRACE_ITER_LAST_BIT
1157};
1158
1159/*
1160 * By redefining C, we can make TRACE_FLAGS a list of masks that
1161 * use the bits as defined above.
1162 */
1163#undef C
1164#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
1165
1166enum trace_iterator_flags { TRACE_FLAGS };
1167
1168/*
1169 * TRACE_ITER_SYM_MASK masks the options in trace_flags that
1170 * control the output of kernel symbols.
1171 */
1172#define TRACE_ITER_SYM_MASK \
1173 (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
1174
1175extern struct tracer nop_trace;
1176
1177#ifdef CONFIG_BRANCH_TRACER
1178extern int enable_branch_tracing(struct trace_array *tr);
1179extern void disable_branch_tracing(void);
1180static inline int trace_branch_enable(struct trace_array *tr)
1181{
1182 if (tr->trace_flags & TRACE_ITER_BRANCH)
1183 return enable_branch_tracing(tr);
1184 return 0;
1185}
1186static inline void trace_branch_disable(void)
1187{
1188 /* due to races, always disable */
1189 disable_branch_tracing();
1190}
1191#else
1192static inline int trace_branch_enable(struct trace_array *tr)
1193{
1194 return 0;
1195}
1196static inline void trace_branch_disable(void)
1197{
1198}
1199#endif /* CONFIG_BRANCH_TRACER */
1200
1201/* set ring buffers to default size if not already done so */
1202int tracing_update_buffers(void);
1203
1204struct ftrace_event_field {
1205 struct list_head link;
1206 const char *name;
1207 const char *type;
1208 int filter_type;
1209 int offset;
1210 int size;
1211 int is_signed;
1212};
1213
1214struct event_filter {
1215 int n_preds; /* Number assigned */
1216 int a_preds; /* allocated */
1217 struct filter_pred __rcu *preds;
1218 struct filter_pred __rcu *root;
1219 char *filter_string;
1220};
1221
1222struct event_subsystem {
1223 struct list_head list;
1224 const char *name;
1225 struct event_filter *filter;
1226 int ref_count;
1227};
1228
1229struct trace_subsystem_dir {
1230 struct list_head list;
1231 struct event_subsystem *subsystem;
1232 struct trace_array *tr;
1233 struct dentry *entry;
1234 int ref_count;
1235 int nr_events;
1236};
1237
1238extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
1239 struct ring_buffer *buffer,
1240 struct ring_buffer_event *event);
1241
1242void trace_buffer_unlock_commit_regs(struct trace_array *tr,
1243 struct ring_buffer *buffer,
1244 struct ring_buffer_event *event,
1245 unsigned long flags, int pc,
1246 struct pt_regs *regs);
1247
1248static inline void trace_buffer_unlock_commit(struct trace_array *tr,
1249 struct ring_buffer *buffer,
1250 struct ring_buffer_event *event,
1251 unsigned long flags, int pc)
1252{
1253 trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
1254}
1255
1256DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
1257DECLARE_PER_CPU(int, trace_buffered_event_cnt);
1258void trace_buffered_event_disable(void);
1259void trace_buffered_event_enable(void);
1260
1261static inline void
1262__trace_event_discard_commit(struct ring_buffer *buffer,
1263 struct ring_buffer_event *event)
1264{
1265 if (this_cpu_read(trace_buffered_event) == event) {
1266 /* Simply release the temp buffer */
1267 this_cpu_dec(trace_buffered_event_cnt);
1268 return;
1269 }
1270 ring_buffer_discard_commit(buffer, event);
1271}
1272
1273/*
1274 * Helper function for event_trigger_unlock_commit{_regs}().
1275 * If there are event triggers attached to this event that requires
1276 * filtering against its fields, then they wil be called as the
1277 * entry already holds the field information of the current event.
1278 *
1279 * It also checks if the event should be discarded or not.
1280 * It is to be discarded if the event is soft disabled and the
1281 * event was only recorded to process triggers, or if the event
1282 * filter is active and this event did not match the filters.
1283 *
1284 * Returns true if the event is discarded, false otherwise.
1285 */
1286static inline bool
1287__event_trigger_test_discard(struct trace_event_file *file,
1288 struct ring_buffer *buffer,
1289 struct ring_buffer_event *event,
1290 void *entry,
1291 enum event_trigger_type *tt)
1292{
1293 unsigned long eflags = file->flags;
1294
1295 if (eflags & EVENT_FILE_FL_TRIGGER_COND)
1296 *tt = event_triggers_call(file, entry);
1297
1298 if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
1299 (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
1300 !filter_match_preds(file->filter, entry))) {
1301 __trace_event_discard_commit(buffer, event);
1302 return true;
1303 }
1304
1305 return false;
1306}
1307
1308/**
1309 * event_trigger_unlock_commit - handle triggers and finish event commit
1310 * @file: The file pointer assoctiated to the event
1311 * @buffer: The ring buffer that the event is being written to
1312 * @event: The event meta data in the ring buffer
1313 * @entry: The event itself
1314 * @irq_flags: The state of the interrupts at the start of the event
1315 * @pc: The state of the preempt count at the start of the event.
1316 *
1317 * This is a helper function to handle triggers that require data
1318 * from the event itself. It also tests the event against filters and
1319 * if the event is soft disabled and should be discarded.
1320 */
1321static inline void
1322event_trigger_unlock_commit(struct trace_event_file *file,
1323 struct ring_buffer *buffer,
1324 struct ring_buffer_event *event,
1325 void *entry, unsigned long irq_flags, int pc)
1326{
1327 enum event_trigger_type tt = ETT_NONE;
1328
1329 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1330 trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
1331
1332 if (tt)
1333 event_triggers_post_call(file, tt, entry);
1334}
1335
1336/**
1337 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
1338 * @file: The file pointer assoctiated to the event
1339 * @buffer: The ring buffer that the event is being written to
1340 * @event: The event meta data in the ring buffer
1341 * @entry: The event itself
1342 * @irq_flags: The state of the interrupts at the start of the event
1343 * @pc: The state of the preempt count at the start of the event.
1344 *
1345 * This is a helper function to handle triggers that require data
1346 * from the event itself. It also tests the event against filters and
1347 * if the event is soft disabled and should be discarded.
1348 *
1349 * Same as event_trigger_unlock_commit() but calls
1350 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
1351 */
1352static inline void
1353event_trigger_unlock_commit_regs(struct trace_event_file *file,
1354 struct ring_buffer *buffer,
1355 struct ring_buffer_event *event,
1356 void *entry, unsigned long irq_flags, int pc,
1357 struct pt_regs *regs)
1358{
1359 enum event_trigger_type tt = ETT_NONE;
1360
1361 if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
1362 trace_buffer_unlock_commit_regs(file->tr, buffer, event,
1363 irq_flags, pc, regs);
1364
1365 if (tt)
1366 event_triggers_post_call(file, tt, entry);
1367}
1368
1369#define FILTER_PRED_INVALID ((unsigned short)-1)
1370#define FILTER_PRED_IS_RIGHT (1 << 15)
1371#define FILTER_PRED_FOLD (1 << 15)
1372
1373/*
1374 * The max preds is the size of unsigned short with
1375 * two flags at the MSBs. One bit is used for both the IS_RIGHT
1376 * and FOLD flags. The other is reserved.
1377 *
1378 * 2^14 preds is way more than enough.
1379 */
1380#define MAX_FILTER_PRED 16384
1381
1382struct filter_pred;
1383struct regex;
1384
1385typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
1386
1387typedef int (*regex_match_func)(char *str, struct regex *r, int len);
1388
1389enum regex_type {
1390 MATCH_FULL = 0,
1391 MATCH_FRONT_ONLY,
1392 MATCH_MIDDLE_ONLY,
1393 MATCH_END_ONLY,
1394 MATCH_GLOB,
1395};
1396
1397struct regex {
1398 char pattern[MAX_FILTER_STR_VAL];
1399 int len;
1400 int field_len;
1401 regex_match_func match;
1402};
1403
1404struct filter_pred {
1405 filter_pred_fn_t fn;
1406 u64 val;
1407 struct regex regex;
1408 unsigned short *ops;
1409 struct ftrace_event_field *field;
1410 int offset;
1411 int not;
1412 int op;
1413 unsigned short index;
1414 unsigned short parent;
1415 unsigned short left;
1416 unsigned short right;
1417};
1418
1419static inline bool is_string_field(struct ftrace_event_field *field)
1420{
1421 return field->filter_type == FILTER_DYN_STRING ||
1422 field->filter_type == FILTER_STATIC_STRING ||
1423 field->filter_type == FILTER_PTR_STRING ||
1424 field->filter_type == FILTER_COMM;
1425}
1426
1427static inline bool is_function_field(struct ftrace_event_field *field)
1428{
1429 return field->filter_type == FILTER_TRACE_FN;
1430}
1431
1432extern enum regex_type
1433filter_parse_regex(char *buff, int len, char **search, int *not);
1434extern void print_event_filter(struct trace_event_file *file,
1435 struct trace_seq *s);
1436extern int apply_event_filter(struct trace_event_file *file,
1437 char *filter_string);
1438extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1439 char *filter_string);
1440extern void print_subsystem_event_filter(struct event_subsystem *system,
1441 struct trace_seq *s);
1442extern int filter_assign_type(const char *type);
1443extern int create_event_filter(struct trace_event_call *call,
1444 char *filter_str, bool set_str,
1445 struct event_filter **filterp);
1446extern void free_event_filter(struct event_filter *filter);
1447
1448struct ftrace_event_field *
1449trace_find_event_field(struct trace_event_call *call, char *name);
1450
1451extern void trace_event_enable_cmd_record(bool enable);
1452extern void trace_event_enable_tgid_record(bool enable);
1453
1454extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1455extern int event_trace_del_tracer(struct trace_array *tr);
1456
1457extern struct trace_event_file *find_event_file(struct trace_array *tr,
1458 const char *system,
1459 const char *event);
1460
1461static inline void *event_file_data(struct file *filp)
1462{
1463 return ACCESS_ONCE(file_inode(filp)->i_private);
1464}
1465
1466extern struct mutex event_mutex;
1467extern struct list_head ftrace_events;
1468
1469extern const struct file_operations event_trigger_fops;
1470extern const struct file_operations event_hist_fops;
1471
1472#ifdef CONFIG_HIST_TRIGGERS
1473extern int register_trigger_hist_cmd(void);
1474extern int register_trigger_hist_enable_disable_cmds(void);
1475#else
1476static inline int register_trigger_hist_cmd(void) { return 0; }
1477static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1478#endif
1479
1480extern int register_trigger_cmds(void);
1481extern void clear_event_triggers(struct trace_array *tr);
1482
1483struct event_trigger_data {
1484 unsigned long count;
1485 int ref;
1486 struct event_trigger_ops *ops;
1487 struct event_command *cmd_ops;
1488 struct event_filter __rcu *filter;
1489 char *filter_str;
1490 void *private_data;
1491 bool paused;
1492 bool paused_tmp;
1493 struct list_head list;
1494 char *name;
1495 struct list_head named_list;
1496 struct event_trigger_data *named_data;
1497};
1498
1499/* Avoid typos */
1500#define ENABLE_EVENT_STR "enable_event"
1501#define DISABLE_EVENT_STR "disable_event"
1502#define ENABLE_HIST_STR "enable_hist"
1503#define DISABLE_HIST_STR "disable_hist"
1504
1505struct enable_trigger_data {
1506 struct trace_event_file *file;
1507 bool enable;
1508 bool hist;
1509};
1510
1511extern int event_enable_trigger_print(struct seq_file *m,
1512 struct event_trigger_ops *ops,
1513 struct event_trigger_data *data);
1514extern void event_enable_trigger_free(struct event_trigger_ops *ops,
1515 struct event_trigger_data *data);
1516extern int event_enable_trigger_func(struct event_command *cmd_ops,
1517 struct trace_event_file *file,
1518 char *glob, char *cmd, char *param);
1519extern int event_enable_register_trigger(char *glob,
1520 struct event_trigger_ops *ops,
1521 struct event_trigger_data *data,
1522 struct trace_event_file *file);
1523extern void event_enable_unregister_trigger(char *glob,
1524 struct event_trigger_ops *ops,
1525 struct event_trigger_data *test,
1526 struct trace_event_file *file);
1527extern void trigger_data_free(struct event_trigger_data *data);
1528extern int event_trigger_init(struct event_trigger_ops *ops,
1529 struct event_trigger_data *data);
1530extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
1531 int trigger_enable);
1532extern void update_cond_flag(struct trace_event_file *file);
1533extern void unregister_trigger(char *glob, struct event_trigger_ops *ops,
1534 struct event_trigger_data *test,
1535 struct trace_event_file *file);
1536extern int set_trigger_filter(char *filter_str,
1537 struct event_trigger_data *trigger_data,
1538 struct trace_event_file *file);
1539extern struct event_trigger_data *find_named_trigger(const char *name);
1540extern bool is_named_trigger(struct event_trigger_data *test);
1541extern int save_named_trigger(const char *name,
1542 struct event_trigger_data *data);
1543extern void del_named_trigger(struct event_trigger_data *data);
1544extern void pause_named_trigger(struct event_trigger_data *data);
1545extern void unpause_named_trigger(struct event_trigger_data *data);
1546extern void set_named_trigger_data(struct event_trigger_data *data,
1547 struct event_trigger_data *named_data);
1548extern int register_event_command(struct event_command *cmd);
1549extern int unregister_event_command(struct event_command *cmd);
1550extern int register_trigger_hist_enable_disable_cmds(void);
1551
1552/**
1553 * struct event_trigger_ops - callbacks for trace event triggers
1554 *
1555 * The methods in this structure provide per-event trigger hooks for
1556 * various trigger operations.
1557 *
1558 * All the methods below, except for @init() and @free(), must be
1559 * implemented.
1560 *
1561 * @func: The trigger 'probe' function called when the triggering
1562 * event occurs. The data passed into this callback is the data
1563 * that was supplied to the event_command @reg() function that
1564 * registered the trigger (see struct event_command) along with
1565 * the trace record, rec.
1566 *
1567 * @init: An optional initialization function called for the trigger
1568 * when the trigger is registered (via the event_command reg()
1569 * function). This can be used to perform per-trigger
1570 * initialization such as incrementing a per-trigger reference
1571 * count, for instance. This is usually implemented by the
1572 * generic utility function @event_trigger_init() (see
1573 * trace_event_triggers.c).
1574 *
1575 * @free: An optional de-initialization function called for the
1576 * trigger when the trigger is unregistered (via the
1577 * event_command @reg() function). This can be used to perform
1578 * per-trigger de-initialization such as decrementing a
1579 * per-trigger reference count and freeing corresponding trigger
1580 * data, for instance. This is usually implemented by the
1581 * generic utility function @event_trigger_free() (see
1582 * trace_event_triggers.c).
1583 *
1584 * @print: The callback function invoked to have the trigger print
1585 * itself. This is usually implemented by a wrapper function
1586 * that calls the generic utility function @event_trigger_print()
1587 * (see trace_event_triggers.c).
1588 */
1589struct event_trigger_ops {
1590 void (*func)(struct event_trigger_data *data,
1591 void *rec);
1592 int (*init)(struct event_trigger_ops *ops,
1593 struct event_trigger_data *data);
1594 void (*free)(struct event_trigger_ops *ops,
1595 struct event_trigger_data *data);
1596 int (*print)(struct seq_file *m,
1597 struct event_trigger_ops *ops,
1598 struct event_trigger_data *data);
1599};
1600
1601/**
1602 * struct event_command - callbacks and data members for event commands
1603 *
1604 * Event commands are invoked by users by writing the command name
1605 * into the 'trigger' file associated with a trace event. The
1606 * parameters associated with a specific invocation of an event
1607 * command are used to create an event trigger instance, which is
1608 * added to the list of trigger instances associated with that trace
1609 * event. When the event is hit, the set of triggers associated with
1610 * that event is invoked.
1611 *
1612 * The data members in this structure provide per-event command data
1613 * for various event commands.
1614 *
1615 * All the data members below, except for @post_trigger, must be set
1616 * for each event command.
1617 *
1618 * @name: The unique name that identifies the event command. This is
1619 * the name used when setting triggers via trigger files.
1620 *
1621 * @trigger_type: A unique id that identifies the event command
1622 * 'type'. This value has two purposes, the first to ensure that
1623 * only one trigger of the same type can be set at a given time
1624 * for a particular event e.g. it doesn't make sense to have both
1625 * a traceon and traceoff trigger attached to a single event at
1626 * the same time, so traceon and traceoff have the same type
1627 * though they have different names. The @trigger_type value is
1628 * also used as a bit value for deferring the actual trigger
1629 * action until after the current event is finished. Some
1630 * commands need to do this if they themselves log to the trace
1631 * buffer (see the @post_trigger() member below). @trigger_type
1632 * values are defined by adding new values to the trigger_type
1633 * enum in include/linux/trace_events.h.
1634 *
1635 * @flags: See the enum event_command_flags below.
1636 *
1637 * All the methods below, except for @set_filter() and @unreg_all(),
1638 * must be implemented.
1639 *
1640 * @func: The callback function responsible for parsing and
1641 * registering the trigger written to the 'trigger' file by the
1642 * user. It allocates the trigger instance and registers it with
1643 * the appropriate trace event. It makes use of the other
1644 * event_command callback functions to orchestrate this, and is
1645 * usually implemented by the generic utility function
1646 * @event_trigger_callback() (see trace_event_triggers.c).
1647 *
1648 * @reg: Adds the trigger to the list of triggers associated with the
1649 * event, and enables the event trigger itself, after
1650 * initializing it (via the event_trigger_ops @init() function).
1651 * This is also where commands can use the @trigger_type value to
1652 * make the decision as to whether or not multiple instances of
1653 * the trigger should be allowed. This is usually implemented by
1654 * the generic utility function @register_trigger() (see
1655 * trace_event_triggers.c).
1656 *
1657 * @unreg: Removes the trigger from the list of triggers associated
1658 * with the event, and disables the event trigger itself, after
1659 * initializing it (via the event_trigger_ops @free() function).
1660 * This is usually implemented by the generic utility function
1661 * @unregister_trigger() (see trace_event_triggers.c).
1662 *
1663 * @unreg_all: An optional function called to remove all the triggers
1664 * from the list of triggers associated with the event. Called
1665 * when a trigger file is opened in truncate mode.
1666 *
1667 * @set_filter: An optional function called to parse and set a filter
1668 * for the trigger. If no @set_filter() method is set for the
1669 * event command, filters set by the user for the command will be
1670 * ignored. This is usually implemented by the generic utility
1671 * function @set_trigger_filter() (see trace_event_triggers.c).
1672 *
1673 * @get_trigger_ops: The callback function invoked to retrieve the
1674 * event_trigger_ops implementation associated with the command.
1675 */
1676struct event_command {
1677 struct list_head list;
1678 char *name;
1679 enum event_trigger_type trigger_type;
1680 int flags;
1681 int (*func)(struct event_command *cmd_ops,
1682 struct trace_event_file *file,
1683 char *glob, char *cmd, char *params);
1684 int (*reg)(char *glob,
1685 struct event_trigger_ops *ops,
1686 struct event_trigger_data *data,
1687 struct trace_event_file *file);
1688 void (*unreg)(char *glob,
1689 struct event_trigger_ops *ops,
1690 struct event_trigger_data *data,
1691 struct trace_event_file *file);
1692 void (*unreg_all)(struct trace_event_file *file);
1693 int (*set_filter)(char *filter_str,
1694 struct event_trigger_data *data,
1695 struct trace_event_file *file);
1696 struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
1697};
1698
1699/**
1700 * enum event_command_flags - flags for struct event_command
1701 *
1702 * @POST_TRIGGER: A flag that says whether or not this command needs
1703 * to have its action delayed until after the current event has
1704 * been closed. Some triggers need to avoid being invoked while
1705 * an event is currently in the process of being logged, since
1706 * the trigger may itself log data into the trace buffer. Thus
1707 * we make sure the current event is committed before invoking
1708 * those triggers. To do that, the trigger invocation is split
1709 * in two - the first part checks the filter using the current
1710 * trace record; if a command has the @post_trigger flag set, it
1711 * sets a bit for itself in the return value, otherwise it
1712 * directly invokes the trigger. Once all commands have been
1713 * either invoked or set their return flag, the current record is
1714 * either committed or discarded. At that point, if any commands
1715 * have deferred their triggers, those commands are finally
1716 * invoked following the close of the current event. In other
1717 * words, if the event_trigger_ops @func() probe implementation
1718 * itself logs to the trace buffer, this flag should be set,
1719 * otherwise it can be left unspecified.
1720 *
1721 * @NEEDS_REC: A flag that says whether or not this command needs
1722 * access to the trace record in order to perform its function,
1723 * regardless of whether or not it has a filter associated with
1724 * it (filters make a trigger require access to the trace record
1725 * but are not always present).
1726 */
1727enum event_command_flags {
1728 EVENT_CMD_FL_POST_TRIGGER = 1,
1729 EVENT_CMD_FL_NEEDS_REC = 2,
1730};
1731
1732static inline bool event_command_post_trigger(struct event_command *cmd_ops)
1733{
1734 return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
1735}
1736
1737static inline bool event_command_needs_rec(struct event_command *cmd_ops)
1738{
1739 return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
1740}
1741
1742extern int trace_event_enable_disable(struct trace_event_file *file,
1743 int enable, int soft_disable);
1744extern int tracing_alloc_snapshot(void);
1745
1746extern const char *__start___trace_bprintk_fmt[];
1747extern const char *__stop___trace_bprintk_fmt[];
1748
1749extern const char *__start___tracepoint_str[];
1750extern const char *__stop___tracepoint_str[];
1751
1752void trace_printk_control(bool enabled);
1753void trace_printk_init_buffers(void);
1754void trace_printk_start_comm(void);
1755int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1756int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1757
1758/*
1759 * Normal trace_printk() and friends allocates special buffers
1760 * to do the manipulation, as well as saves the print formats
1761 * into sections to display. But the trace infrastructure wants
1762 * to use these without the added overhead at the price of being
1763 * a bit slower (used mainly for warnings, where we don't care
1764 * about performance). The internal_trace_puts() is for such
1765 * a purpose.
1766 */
1767#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
1768
1769#undef FTRACE_ENTRY
1770#define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \
1771 extern struct trace_event_call \
1772 __aligned(4) event_##call;
1773#undef FTRACE_ENTRY_DUP
1774#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
1775 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1776 filter)
1777#undef FTRACE_ENTRY_PACKED
1778#define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \
1779 FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
1780 filter)
1781
1782#include "trace_entries.h"
1783
1784#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1785int perf_ftrace_event_register(struct trace_event_call *call,
1786 enum trace_reg type, void *data);
1787#else
1788#define perf_ftrace_event_register NULL
1789#endif
1790
1791#ifdef CONFIG_FTRACE_SYSCALLS
1792void init_ftrace_syscalls(void);
1793const char *get_syscall_name(int syscall);
1794#else
1795static inline void init_ftrace_syscalls(void) { }
1796static inline const char *get_syscall_name(int syscall)
1797{
1798 return NULL;
1799}
1800#endif
1801
1802#ifdef CONFIG_EVENT_TRACING
1803void trace_event_init(void);
1804void trace_event_eval_update(struct trace_eval_map **map, int len);
1805#else
1806static inline void __init trace_event_init(void) { }
1807static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
1808#endif
1809
1810extern struct trace_iterator *tracepoint_print_iter;
1811
1812#endif /* _LINUX_KERNEL_TRACE_H */