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Linux kernel mirror (for testing)
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linux
1#ifndef _LINUX_FTRACE_EVENT_H
2#define _LINUX_FTRACE_EVENT_H
3
4#include <linux/ring_buffer.h>
5#include <linux/trace_seq.h>
6#include <linux/percpu.h>
7#include <linux/hardirq.h>
8#include <linux/perf_event.h>
9
10struct trace_array;
11struct trace_buffer;
12struct tracer;
13struct dentry;
14
15struct trace_print_flags {
16 unsigned long mask;
17 const char *name;
18};
19
20struct trace_print_flags_u64 {
21 unsigned long long mask;
22 const char *name;
23};
24
25const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
26 unsigned long flags,
27 const struct trace_print_flags *flag_array);
28
29const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
30 const struct trace_print_flags *symbol_array);
31
32#if BITS_PER_LONG == 32
33const char *ftrace_print_symbols_seq_u64(struct trace_seq *p,
34 unsigned long long val,
35 const struct trace_print_flags_u64
36 *symbol_array);
37#endif
38
39const char *ftrace_print_hex_seq(struct trace_seq *p,
40 const unsigned char *buf, int len);
41
42struct trace_iterator;
43struct trace_event;
44
45int ftrace_raw_output_prep(struct trace_iterator *iter,
46 struct trace_event *event);
47
48/*
49 * The trace entry - the most basic unit of tracing. This is what
50 * is printed in the end as a single line in the trace output, such as:
51 *
52 * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
53 */
54struct trace_entry {
55 unsigned short type;
56 unsigned char flags;
57 unsigned char preempt_count;
58 int pid;
59};
60
61#define FTRACE_MAX_EVENT \
62 ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1)
63
64/*
65 * Trace iterator - used by printout routines who present trace
66 * results to users and which routines might sleep, etc:
67 */
68struct trace_iterator {
69 struct trace_array *tr;
70 struct tracer *trace;
71 struct trace_buffer *trace_buffer;
72 void *private;
73 int cpu_file;
74 struct mutex mutex;
75 struct ring_buffer_iter **buffer_iter;
76 unsigned long iter_flags;
77
78 /* trace_seq for __print_flags() and __print_symbolic() etc. */
79 struct trace_seq tmp_seq;
80
81 cpumask_var_t started;
82
83 /* it's true when current open file is snapshot */
84 bool snapshot;
85
86 /* The below is zeroed out in pipe_read */
87 struct trace_seq seq;
88 struct trace_entry *ent;
89 unsigned long lost_events;
90 int leftover;
91 int ent_size;
92 int cpu;
93 u64 ts;
94
95 loff_t pos;
96 long idx;
97
98 /* All new field here will be zeroed out in pipe_read */
99};
100
101enum trace_iter_flags {
102 TRACE_FILE_LAT_FMT = 1,
103 TRACE_FILE_ANNOTATE = 2,
104 TRACE_FILE_TIME_IN_NS = 4,
105};
106
107
108typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter,
109 int flags, struct trace_event *event);
110
111struct trace_event_functions {
112 trace_print_func trace;
113 trace_print_func raw;
114 trace_print_func hex;
115 trace_print_func binary;
116};
117
118struct trace_event {
119 struct hlist_node node;
120 struct list_head list;
121 int type;
122 struct trace_event_functions *funcs;
123};
124
125extern int register_ftrace_event(struct trace_event *event);
126extern int unregister_ftrace_event(struct trace_event *event);
127
128/* Return values for print_line callback */
129enum print_line_t {
130 TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */
131 TRACE_TYPE_HANDLED = 1,
132 TRACE_TYPE_UNHANDLED = 2, /* Relay to other output functions */
133 TRACE_TYPE_NO_CONSUME = 3 /* Handled but ask to not consume */
134};
135
136void tracing_generic_entry_update(struct trace_entry *entry,
137 unsigned long flags,
138 int pc);
139struct ftrace_event_file;
140
141struct ring_buffer_event *
142trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer,
143 struct ftrace_event_file *ftrace_file,
144 int type, unsigned long len,
145 unsigned long flags, int pc);
146struct ring_buffer_event *
147trace_current_buffer_lock_reserve(struct ring_buffer **current_buffer,
148 int type, unsigned long len,
149 unsigned long flags, int pc);
150void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
151 struct ring_buffer_event *event,
152 unsigned long flags, int pc);
153void trace_buffer_unlock_commit(struct ring_buffer *buffer,
154 struct ring_buffer_event *event,
155 unsigned long flags, int pc);
156void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer,
157 struct ring_buffer_event *event,
158 unsigned long flags, int pc,
159 struct pt_regs *regs);
160void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
161 struct ring_buffer_event *event);
162
163void tracing_record_cmdline(struct task_struct *tsk);
164
165struct event_filter;
166
167enum trace_reg {
168 TRACE_REG_REGISTER,
169 TRACE_REG_UNREGISTER,
170#ifdef CONFIG_PERF_EVENTS
171 TRACE_REG_PERF_REGISTER,
172 TRACE_REG_PERF_UNREGISTER,
173 TRACE_REG_PERF_OPEN,
174 TRACE_REG_PERF_CLOSE,
175 TRACE_REG_PERF_ADD,
176 TRACE_REG_PERF_DEL,
177#endif
178};
179
180struct ftrace_event_call;
181
182struct ftrace_event_class {
183 char *system;
184 void *probe;
185#ifdef CONFIG_PERF_EVENTS
186 void *perf_probe;
187#endif
188 int (*reg)(struct ftrace_event_call *event,
189 enum trace_reg type, void *data);
190 int (*define_fields)(struct ftrace_event_call *);
191 struct list_head *(*get_fields)(struct ftrace_event_call *);
192 struct list_head fields;
193 int (*raw_init)(struct ftrace_event_call *);
194};
195
196extern int ftrace_event_reg(struct ftrace_event_call *event,
197 enum trace_reg type, void *data);
198
199enum {
200 TRACE_EVENT_FL_FILTERED_BIT,
201 TRACE_EVENT_FL_CAP_ANY_BIT,
202 TRACE_EVENT_FL_NO_SET_FILTER_BIT,
203 TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
204 TRACE_EVENT_FL_WAS_ENABLED_BIT,
205};
206
207/*
208 * Event flags:
209 * FILTERED - The event has a filter attached
210 * CAP_ANY - Any user can enable for perf
211 * NO_SET_FILTER - Set when filter has error and is to be ignored
212 * IGNORE_ENABLE - For ftrace internal events, do not enable with debugfs file
213 * WAS_ENABLED - Set and stays set when an event was ever enabled
214 * (used for module unloading, if a module event is enabled,
215 * it is best to clear the buffers that used it).
216 */
217enum {
218 TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT),
219 TRACE_EVENT_FL_CAP_ANY = (1 << TRACE_EVENT_FL_CAP_ANY_BIT),
220 TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
221 TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
222 TRACE_EVENT_FL_WAS_ENABLED = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT),
223};
224
225struct ftrace_event_call {
226 struct list_head list;
227 struct ftrace_event_class *class;
228 char *name;
229 struct trace_event event;
230 const char *print_fmt;
231 struct event_filter *filter;
232 struct list_head *files;
233 void *mod;
234 void *data;
235 /*
236 * bit 0: filter_active
237 * bit 1: allow trace by non root (cap any)
238 * bit 2: failed to apply filter
239 * bit 3: ftrace internal event (do not enable)
240 * bit 4: Event was enabled by module
241 */
242 int flags; /* static flags of different events */
243
244#ifdef CONFIG_PERF_EVENTS
245 int perf_refcount;
246 struct hlist_head __percpu *perf_events;
247#endif
248};
249
250struct trace_array;
251struct ftrace_subsystem_dir;
252
253enum {
254 FTRACE_EVENT_FL_ENABLED_BIT,
255 FTRACE_EVENT_FL_RECORDED_CMD_BIT,
256 FTRACE_EVENT_FL_SOFT_MODE_BIT,
257 FTRACE_EVENT_FL_SOFT_DISABLED_BIT,
258};
259
260/*
261 * Ftrace event file flags:
262 * ENABLED - The event is enabled
263 * RECORDED_CMD - The comms should be recorded at sched_switch
264 * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED
265 * SOFT_DISABLED - When set, do not trace the event (even though its
266 * tracepoint may be enabled)
267 */
268enum {
269 FTRACE_EVENT_FL_ENABLED = (1 << FTRACE_EVENT_FL_ENABLED_BIT),
270 FTRACE_EVENT_FL_RECORDED_CMD = (1 << FTRACE_EVENT_FL_RECORDED_CMD_BIT),
271 FTRACE_EVENT_FL_SOFT_MODE = (1 << FTRACE_EVENT_FL_SOFT_MODE_BIT),
272 FTRACE_EVENT_FL_SOFT_DISABLED = (1 << FTRACE_EVENT_FL_SOFT_DISABLED_BIT),
273};
274
275struct ftrace_event_file {
276 struct list_head list;
277 struct ftrace_event_call *event_call;
278 struct dentry *dir;
279 struct trace_array *tr;
280 struct ftrace_subsystem_dir *system;
281
282 /*
283 * 32 bit flags:
284 * bit 0: enabled
285 * bit 1: enabled cmd record
286 * bit 2: enable/disable with the soft disable bit
287 * bit 3: soft disabled
288 *
289 * Note: The bits must be set atomically to prevent races
290 * from other writers. Reads of flags do not need to be in
291 * sync as they occur in critical sections. But the way flags
292 * is currently used, these changes do not affect the code
293 * except that when a change is made, it may have a slight
294 * delay in propagating the changes to other CPUs due to
295 * caching and such. Which is mostly OK ;-)
296 */
297 unsigned long flags;
298 atomic_t sm_ref; /* soft-mode reference counter */
299};
300
301#define __TRACE_EVENT_FLAGS(name, value) \
302 static int __init trace_init_flags_##name(void) \
303 { \
304 event_##name.flags = value; \
305 return 0; \
306 } \
307 early_initcall(trace_init_flags_##name);
308
309#define PERF_MAX_TRACE_SIZE 2048
310
311#define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */
312
313extern void destroy_preds(struct ftrace_event_call *call);
314extern int filter_match_preds(struct event_filter *filter, void *rec);
315extern int filter_current_check_discard(struct ring_buffer *buffer,
316 struct ftrace_event_call *call,
317 void *rec,
318 struct ring_buffer_event *event);
319
320enum {
321 FILTER_OTHER = 0,
322 FILTER_STATIC_STRING,
323 FILTER_DYN_STRING,
324 FILTER_PTR_STRING,
325 FILTER_TRACE_FN,
326};
327
328#define EVENT_STORAGE_SIZE 128
329extern struct mutex event_storage_mutex;
330extern char event_storage[EVENT_STORAGE_SIZE];
331
332extern int trace_event_raw_init(struct ftrace_event_call *call);
333extern int trace_define_field(struct ftrace_event_call *call, const char *type,
334 const char *name, int offset, int size,
335 int is_signed, int filter_type);
336extern int trace_add_event_call(struct ftrace_event_call *call);
337extern int trace_remove_event_call(struct ftrace_event_call *call);
338
339#define is_signed_type(type) (((type)(-1)) < (type)1)
340
341int trace_set_clr_event(const char *system, const char *event, int set);
342
343/*
344 * The double __builtin_constant_p is because gcc will give us an error
345 * if we try to allocate the static variable to fmt if it is not a
346 * constant. Even with the outer if statement optimizing out.
347 */
348#define event_trace_printk(ip, fmt, args...) \
349do { \
350 __trace_printk_check_format(fmt, ##args); \
351 tracing_record_cmdline(current); \
352 if (__builtin_constant_p(fmt)) { \
353 static const char *trace_printk_fmt \
354 __attribute__((section("__trace_printk_fmt"))) = \
355 __builtin_constant_p(fmt) ? fmt : NULL; \
356 \
357 __trace_bprintk(ip, trace_printk_fmt, ##args); \
358 } else \
359 __trace_printk(ip, fmt, ##args); \
360} while (0)
361
362#ifdef CONFIG_PERF_EVENTS
363struct perf_event;
364
365DECLARE_PER_CPU(struct pt_regs, perf_trace_regs);
366
367extern int perf_trace_init(struct perf_event *event);
368extern void perf_trace_destroy(struct perf_event *event);
369extern int perf_trace_add(struct perf_event *event, int flags);
370extern void perf_trace_del(struct perf_event *event, int flags);
371extern int ftrace_profile_set_filter(struct perf_event *event, int event_id,
372 char *filter_str);
373extern void ftrace_profile_free_filter(struct perf_event *event);
374extern void *perf_trace_buf_prepare(int size, unsigned short type,
375 struct pt_regs *regs, int *rctxp);
376
377static inline void
378perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr,
379 u64 count, struct pt_regs *regs, void *head,
380 struct task_struct *task)
381{
382 perf_tp_event(addr, count, raw_data, size, regs, head, rctx, task);
383}
384#endif
385
386#endif /* _LINUX_FTRACE_EVENT_H */