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TOMOYO Linux Cross Reference
Linux/kernel/trace/trace.h

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

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