perf_counter: unify and fix delayed counter wakeup
[safe/jmp/linux-2.6] / include / linux / perf_counter.h
1 /*
2  *  Performance counters:
3  *
4  *   Copyright(C) 2008, Thomas Gleixner <tglx@linutronix.de>
5  *   Copyright(C) 2008, Red Hat, Inc., Ingo Molnar
6  *
7  *  Data type definitions, declarations, prototypes.
8  *
9  *  Started by: Thomas Gleixner and Ingo Molnar
10  *
11  *  For licencing details see kernel-base/COPYING
12  */
13 #ifndef _LINUX_PERF_COUNTER_H
14 #define _LINUX_PERF_COUNTER_H
15
16 #include <linux/types.h>
17 #include <linux/ioctl.h>
18 #include <asm/byteorder.h>
19
20 /*
21  * User-space ABI bits:
22  */
23
24 /*
25  * hw_event.type
26  */
27 enum perf_event_types {
28         PERF_TYPE_HARDWARE              = 0,
29         PERF_TYPE_SOFTWARE              = 1,
30         PERF_TYPE_TRACEPOINT            = 2,
31
32         /*
33          * available TYPE space, raw is the max value.
34          */
35
36         PERF_TYPE_RAW                   = 128,
37 };
38
39 /*
40  * Generalized performance counter event types, used by the hw_event.event_id
41  * parameter of the sys_perf_counter_open() syscall:
42  */
43 enum hw_event_ids {
44         /*
45          * Common hardware events, generalized by the kernel:
46          */
47         PERF_COUNT_CPU_CYCLES           = 0,
48         PERF_COUNT_INSTRUCTIONS         = 1,
49         PERF_COUNT_CACHE_REFERENCES     = 2,
50         PERF_COUNT_CACHE_MISSES         = 3,
51         PERF_COUNT_BRANCH_INSTRUCTIONS  = 4,
52         PERF_COUNT_BRANCH_MISSES        = 5,
53         PERF_COUNT_BUS_CYCLES           = 6,
54
55         PERF_HW_EVENTS_MAX              = 7,
56 };
57
58 /*
59  * Special "software" counters provided by the kernel, even if the hardware
60  * does not support performance counters. These counters measure various
61  * physical and sw events of the kernel (and allow the profiling of them as
62  * well):
63  */
64 enum sw_event_ids {
65         PERF_COUNT_CPU_CLOCK            = 0,
66         PERF_COUNT_TASK_CLOCK           = 1,
67         PERF_COUNT_PAGE_FAULTS          = 2,
68         PERF_COUNT_CONTEXT_SWITCHES     = 3,
69         PERF_COUNT_CPU_MIGRATIONS       = 4,
70         PERF_COUNT_PAGE_FAULTS_MIN      = 5,
71         PERF_COUNT_PAGE_FAULTS_MAJ      = 6,
72
73         PERF_SW_EVENTS_MAX              = 7,
74 };
75
76 /*
77  * IRQ-notification data record type:
78  */
79 enum perf_counter_record_type {
80         PERF_RECORD_SIMPLE              = 0,
81         PERF_RECORD_IRQ                 = 1,
82         PERF_RECORD_GROUP               = 2,
83 };
84
85 #define __PERF_COUNTER_MASK(name)                       \
86         (((1ULL << PERF_COUNTER_##name##_BITS) - 1) <<  \
87          PERF_COUNTER_##name##_SHIFT)
88
89 #define PERF_COUNTER_RAW_BITS           1
90 #define PERF_COUNTER_RAW_SHIFT          63
91 #define PERF_COUNTER_RAW_MASK           __PERF_COUNTER_MASK(RAW)
92
93 #define PERF_COUNTER_CONFIG_BITS        63
94 #define PERF_COUNTER_CONFIG_SHIFT       0
95 #define PERF_COUNTER_CONFIG_MASK        __PERF_COUNTER_MASK(CONFIG)
96
97 #define PERF_COUNTER_TYPE_BITS          7
98 #define PERF_COUNTER_TYPE_SHIFT         56
99 #define PERF_COUNTER_TYPE_MASK          __PERF_COUNTER_MASK(TYPE)
100
101 #define PERF_COUNTER_EVENT_BITS         56
102 #define PERF_COUNTER_EVENT_SHIFT        0
103 #define PERF_COUNTER_EVENT_MASK         __PERF_COUNTER_MASK(EVENT)
104
105 /*
106  * Bits that can be set in hw_event.read_format to request that
107  * reads on the counter should return the indicated quantities,
108  * in increasing order of bit value, after the counter value.
109  */
110 enum perf_counter_read_format {
111         PERF_FORMAT_TOTAL_TIME_ENABLED  =  1,
112         PERF_FORMAT_TOTAL_TIME_RUNNING  =  2,
113 };
114
115 /*
116  * Hardware event to monitor via a performance monitoring counter:
117  */
118 struct perf_counter_hw_event {
119         /*
120          * The MSB of the config word signifies if the rest contains cpu
121          * specific (raw) counter configuration data, if unset, the next
122          * 7 bits are an event type and the rest of the bits are the event
123          * identifier.
124          */
125         __u64                   config;
126
127         __u64                   irq_period;
128         __u64                   record_type;
129         __u64                   read_format;
130
131         __u64                   disabled       :  1, /* off by default        */
132                                 nmi            :  1, /* NMI sampling          */
133                                 inherit        :  1, /* children inherit it   */
134                                 pinned         :  1, /* must always be on PMU */
135                                 exclusive      :  1, /* only group on PMU     */
136                                 exclude_user   :  1, /* don't count user      */
137                                 exclude_kernel :  1, /* ditto kernel          */
138                                 exclude_hv     :  1, /* ditto hypervisor      */
139                                 exclude_idle   :  1, /* don't count when idle */
140                                 include_tid    :  1, /* include the tid */
141
142                                 __reserved_1   : 54;
143
144         __u32                   extra_config_len;
145         __u32                   __reserved_4;
146
147         __u64                   __reserved_2;
148         __u64                   __reserved_3;
149 };
150
151 /*
152  * Ioctls that can be done on a perf counter fd:
153  */
154 #define PERF_COUNTER_IOC_ENABLE         _IO('$', 0)
155 #define PERF_COUNTER_IOC_DISABLE        _IO('$', 1)
156
157 /*
158  * Structure of the page that can be mapped via mmap
159  */
160 struct perf_counter_mmap_page {
161         __u32   version;                /* version number of this structure */
162         __u32   compat_version;         /* lowest version this is compat with */
163         __u32   lock;                   /* seqlock for synchronization */
164         __u32   index;                  /* hardware counter identifier */
165         __s64   offset;                 /* add to hardware counter value */
166
167         __u32   data_head;              /* head in the data section */
168 };
169
170 struct perf_event_header {
171         __u32   type;
172         __u32   size;
173 };
174
175 enum perf_event_type {
176         PERF_EVENT_IP           = 0,
177         PERF_EVENT_GROUP        = 1,
178
179         __PERF_EVENT_TID        = 0x100,
180 };
181
182 #ifdef __KERNEL__
183 /*
184  * Kernel-internal data types and definitions:
185  */
186
187 #ifdef CONFIG_PERF_COUNTERS
188 # include <asm/perf_counter.h>
189 #endif
190
191 #include <linux/list.h>
192 #include <linux/mutex.h>
193 #include <linux/rculist.h>
194 #include <linux/rcupdate.h>
195 #include <linux/spinlock.h>
196 #include <linux/hrtimer.h>
197 #include <asm/atomic.h>
198
199 struct task_struct;
200
201 static inline u64 perf_event_raw(struct perf_counter_hw_event *hw_event)
202 {
203         return hw_event->config & PERF_COUNTER_RAW_MASK;
204 }
205
206 static inline u64 perf_event_config(struct perf_counter_hw_event *hw_event)
207 {
208         return hw_event->config & PERF_COUNTER_CONFIG_MASK;
209 }
210
211 static inline u64 perf_event_type(struct perf_counter_hw_event *hw_event)
212 {
213         return (hw_event->config & PERF_COUNTER_TYPE_MASK) >>
214                 PERF_COUNTER_TYPE_SHIFT;
215 }
216
217 static inline u64 perf_event_id(struct perf_counter_hw_event *hw_event)
218 {
219         return hw_event->config & PERF_COUNTER_EVENT_MASK;
220 }
221
222 /**
223  * struct hw_perf_counter - performance counter hardware details:
224  */
225 struct hw_perf_counter {
226 #ifdef CONFIG_PERF_COUNTERS
227         union {
228                 struct { /* hardware */
229                         u64                             config;
230                         unsigned long                   config_base;
231                         unsigned long                   counter_base;
232                         int                             nmi;
233                         unsigned int                    idx;
234                 };
235                 union { /* software */
236                         atomic64_t                      count;
237                         struct hrtimer                  hrtimer;
238                 };
239         };
240         atomic64_t                      prev_count;
241         u64                             irq_period;
242         atomic64_t                      period_left;
243 #endif
244 };
245
246 struct perf_counter;
247
248 /**
249  * struct hw_perf_counter_ops - performance counter hw ops
250  */
251 struct hw_perf_counter_ops {
252         int (*enable)                   (struct perf_counter *counter);
253         void (*disable)                 (struct perf_counter *counter);
254         void (*read)                    (struct perf_counter *counter);
255 };
256
257 /**
258  * enum perf_counter_active_state - the states of a counter
259  */
260 enum perf_counter_active_state {
261         PERF_COUNTER_STATE_ERROR        = -2,
262         PERF_COUNTER_STATE_OFF          = -1,
263         PERF_COUNTER_STATE_INACTIVE     =  0,
264         PERF_COUNTER_STATE_ACTIVE       =  1,
265 };
266
267 struct file;
268
269 struct perf_mmap_data {
270         struct rcu_head                 rcu_head;
271         int                             nr_pages;
272         atomic_t                        wakeup;
273         atomic_t                        head;
274         struct perf_counter_mmap_page   *user_page;
275         void                            *data_pages[0];
276 };
277
278 struct perf_wakeup_entry {
279         struct perf_wakeup_entry *next;
280 };
281
282 /**
283  * struct perf_counter - performance counter kernel representation:
284  */
285 struct perf_counter {
286 #ifdef CONFIG_PERF_COUNTERS
287         struct list_head                list_entry;
288         struct list_head                event_entry;
289         struct list_head                sibling_list;
290         int                             nr_siblings;
291         struct perf_counter             *group_leader;
292         const struct hw_perf_counter_ops *hw_ops;
293
294         enum perf_counter_active_state  state;
295         enum perf_counter_active_state  prev_state;
296         atomic64_t                      count;
297
298         /*
299          * These are the total time in nanoseconds that the counter
300          * has been enabled (i.e. eligible to run, and the task has
301          * been scheduled in, if this is a per-task counter)
302          * and running (scheduled onto the CPU), respectively.
303          *
304          * They are computed from tstamp_enabled, tstamp_running and
305          * tstamp_stopped when the counter is in INACTIVE or ACTIVE state.
306          */
307         u64                             total_time_enabled;
308         u64                             total_time_running;
309
310         /*
311          * These are timestamps used for computing total_time_enabled
312          * and total_time_running when the counter is in INACTIVE or
313          * ACTIVE state, measured in nanoseconds from an arbitrary point
314          * in time.
315          * tstamp_enabled: the notional time when the counter was enabled
316          * tstamp_running: the notional time when the counter was scheduled on
317          * tstamp_stopped: in INACTIVE state, the notional time when the
318          *      counter was scheduled off.
319          */
320         u64                             tstamp_enabled;
321         u64                             tstamp_running;
322         u64                             tstamp_stopped;
323
324         struct perf_counter_hw_event    hw_event;
325         struct hw_perf_counter          hw;
326
327         struct perf_counter_context     *ctx;
328         struct task_struct              *task;
329         struct file                     *filp;
330
331         struct perf_counter             *parent;
332         struct list_head                child_list;
333
334         /*
335          * These accumulate total time (in nanoseconds) that children
336          * counters have been enabled and running, respectively.
337          */
338         atomic64_t                      child_total_time_enabled;
339         atomic64_t                      child_total_time_running;
340
341         /*
342          * Protect attach/detach and child_list:
343          */
344         struct mutex                    mutex;
345
346         int                             oncpu;
347         int                             cpu;
348
349         /* mmap bits */
350         struct mutex                    mmap_mutex;
351         atomic_t                        mmap_count;
352         struct perf_mmap_data           *data;
353
354         /* poll related */
355         wait_queue_head_t               waitq;
356         /* optional: for NMIs */
357         struct perf_wakeup_entry        wakeup;
358
359         void (*destroy)(struct perf_counter *);
360         struct rcu_head                 rcu_head;
361 #endif
362 };
363
364 /**
365  * struct perf_counter_context - counter context structure
366  *
367  * Used as a container for task counters and CPU counters as well:
368  */
369 struct perf_counter_context {
370 #ifdef CONFIG_PERF_COUNTERS
371         /*
372          * Protect the states of the counters in the list,
373          * nr_active, and the list:
374          */
375         spinlock_t              lock;
376         /*
377          * Protect the list of counters.  Locking either mutex or lock
378          * is sufficient to ensure the list doesn't change; to change
379          * the list you need to lock both the mutex and the spinlock.
380          */
381         struct mutex            mutex;
382
383         struct list_head        counter_list;
384         struct list_head        event_list;
385         int                     nr_counters;
386         int                     nr_active;
387         int                     is_active;
388         struct task_struct      *task;
389
390         /*
391          * time_now is the current time in nanoseconds since an arbitrary
392          * point in the past.  For per-task counters, this is based on the
393          * task clock, and for per-cpu counters it is based on the cpu clock.
394          * time_lost is an offset from the task/cpu clock, used to make it
395          * appear that time only passes while the context is scheduled in.
396          */
397         u64                     time_now;
398         u64                     time_lost;
399 #endif
400 };
401
402 /**
403  * struct perf_counter_cpu_context - per cpu counter context structure
404  */
405 struct perf_cpu_context {
406         struct perf_counter_context     ctx;
407         struct perf_counter_context     *task_ctx;
408         int                             active_oncpu;
409         int                             max_pertask;
410         int                             exclusive;
411
412         /*
413          * Recursion avoidance:
414          *
415          * task, softirq, irq, nmi context
416          */
417         int                     recursion[4];
418 };
419
420 /*
421  * Set by architecture code:
422  */
423 extern int perf_max_counters;
424
425 #ifdef CONFIG_PERF_COUNTERS
426 extern const struct hw_perf_counter_ops *
427 hw_perf_counter_init(struct perf_counter *counter);
428
429 extern void perf_counter_task_sched_in(struct task_struct *task, int cpu);
430 extern void perf_counter_task_sched_out(struct task_struct *task, int cpu);
431 extern void perf_counter_task_tick(struct task_struct *task, int cpu);
432 extern void perf_counter_init_task(struct task_struct *child);
433 extern void perf_counter_exit_task(struct task_struct *child);
434 extern void perf_counter_do_pending(void);
435 extern void perf_counter_print_debug(void);
436 extern void perf_counter_unthrottle(void);
437 extern u64 hw_perf_save_disable(void);
438 extern void hw_perf_restore(u64 ctrl);
439 extern int perf_counter_task_disable(void);
440 extern int perf_counter_task_enable(void);
441 extern int hw_perf_group_sched_in(struct perf_counter *group_leader,
442                struct perf_cpu_context *cpuctx,
443                struct perf_counter_context *ctx, int cpu);
444 extern void perf_counter_update_userpage(struct perf_counter *counter);
445
446 extern void perf_counter_output(struct perf_counter *counter,
447                                 int nmi, struct pt_regs *regs);
448 /*
449  * Return 1 for a software counter, 0 for a hardware counter
450  */
451 static inline int is_software_counter(struct perf_counter *counter)
452 {
453         return !perf_event_raw(&counter->hw_event) &&
454                 perf_event_type(&counter->hw_event) != PERF_TYPE_HARDWARE;
455 }
456
457 extern void perf_swcounter_event(u32, u64, int, struct pt_regs *);
458
459 #else
460 static inline void
461 perf_counter_task_sched_in(struct task_struct *task, int cpu)           { }
462 static inline void
463 perf_counter_task_sched_out(struct task_struct *task, int cpu)          { }
464 static inline void
465 perf_counter_task_tick(struct task_struct *task, int cpu)               { }
466 static inline void perf_counter_init_task(struct task_struct *child)    { }
467 static inline void perf_counter_exit_task(struct task_struct *child)    { }
468 static inline void perf_counter_do_pending(void)                        { }
469 static inline void perf_counter_print_debug(void)                       { }
470 static inline void perf_counter_unthrottle(void)                        { }
471 static inline void hw_perf_restore(u64 ctrl)                            { }
472 static inline u64 hw_perf_save_disable(void)                  { return 0; }
473 static inline int perf_counter_task_disable(void)       { return -EINVAL; }
474 static inline int perf_counter_task_enable(void)        { return -EINVAL; }
475
476 static inline void
477 perf_swcounter_event(u32 event, u64 nr, int nmi, struct pt_regs *regs)  { }
478
479 #endif
480
481 #endif /* __KERNEL__ */
482 #endif /* _LINUX_PERF_COUNTER_H */