perf_counter.h 17 KB

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  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. #include <linux/types.h>
  16. #include <linux/ioctl.h>
  17. #include <asm/byteorder.h>
  18. /*
  19. * User-space ABI bits:
  20. */
  21. /*
  22. * hw_event.type
  23. */
  24. enum perf_event_types {
  25. PERF_TYPE_HARDWARE = 0,
  26. PERF_TYPE_SOFTWARE = 1,
  27. PERF_TYPE_TRACEPOINT = 2,
  28. /*
  29. * available TYPE space, raw is the max value.
  30. */
  31. PERF_TYPE_RAW = 128,
  32. };
  33. /*
  34. * Generalized performance counter event types, used by the hw_event.event_id
  35. * parameter of the sys_perf_counter_open() syscall:
  36. */
  37. enum hw_event_ids {
  38. /*
  39. * Common hardware events, generalized by the kernel:
  40. */
  41. PERF_COUNT_CPU_CYCLES = 0,
  42. PERF_COUNT_INSTRUCTIONS = 1,
  43. PERF_COUNT_CACHE_REFERENCES = 2,
  44. PERF_COUNT_CACHE_MISSES = 3,
  45. PERF_COUNT_BRANCH_INSTRUCTIONS = 4,
  46. PERF_COUNT_BRANCH_MISSES = 5,
  47. PERF_COUNT_BUS_CYCLES = 6,
  48. PERF_HW_EVENTS_MAX = 7,
  49. };
  50. /*
  51. * Special "software" counters provided by the kernel, even if the hardware
  52. * does not support performance counters. These counters measure various
  53. * physical and sw events of the kernel (and allow the profiling of them as
  54. * well):
  55. */
  56. enum sw_event_ids {
  57. PERF_COUNT_CPU_CLOCK = 0,
  58. PERF_COUNT_TASK_CLOCK = 1,
  59. PERF_COUNT_PAGE_FAULTS = 2,
  60. PERF_COUNT_CONTEXT_SWITCHES = 3,
  61. PERF_COUNT_CPU_MIGRATIONS = 4,
  62. PERF_COUNT_PAGE_FAULTS_MIN = 5,
  63. PERF_COUNT_PAGE_FAULTS_MAJ = 6,
  64. PERF_SW_EVENTS_MAX = 7,
  65. };
  66. #define __PERF_COUNTER_MASK(name) \
  67. (((1ULL << PERF_COUNTER_##name##_BITS) - 1) << \
  68. PERF_COUNTER_##name##_SHIFT)
  69. #define PERF_COUNTER_RAW_BITS 1
  70. #define PERF_COUNTER_RAW_SHIFT 63
  71. #define PERF_COUNTER_RAW_MASK __PERF_COUNTER_MASK(RAW)
  72. #define PERF_COUNTER_CONFIG_BITS 63
  73. #define PERF_COUNTER_CONFIG_SHIFT 0
  74. #define PERF_COUNTER_CONFIG_MASK __PERF_COUNTER_MASK(CONFIG)
  75. #define PERF_COUNTER_TYPE_BITS 7
  76. #define PERF_COUNTER_TYPE_SHIFT 56
  77. #define PERF_COUNTER_TYPE_MASK __PERF_COUNTER_MASK(TYPE)
  78. #define PERF_COUNTER_EVENT_BITS 56
  79. #define PERF_COUNTER_EVENT_SHIFT 0
  80. #define PERF_COUNTER_EVENT_MASK __PERF_COUNTER_MASK(EVENT)
  81. /*
  82. * Bits that can be set in hw_event.record_type to request information
  83. * in the overflow packets.
  84. */
  85. enum perf_counter_record_format {
  86. PERF_RECORD_IP = 1U << 0,
  87. PERF_RECORD_TID = 1U << 1,
  88. PERF_RECORD_TIME = 1U << 2,
  89. PERF_RECORD_ADDR = 1U << 3,
  90. PERF_RECORD_GROUP = 1U << 4,
  91. PERF_RECORD_CALLCHAIN = 1U << 5,
  92. PERF_RECORD_CONFIG = 1U << 6,
  93. PERF_RECORD_CPU = 1U << 7,
  94. };
  95. /*
  96. * Bits that can be set in hw_event.read_format to request that
  97. * reads on the counter should return the indicated quantities,
  98. * in increasing order of bit value, after the counter value.
  99. */
  100. enum perf_counter_read_format {
  101. PERF_FORMAT_TOTAL_TIME_ENABLED = 1,
  102. PERF_FORMAT_TOTAL_TIME_RUNNING = 2,
  103. };
  104. /*
  105. * Hardware event to monitor via a performance monitoring counter:
  106. */
  107. struct perf_counter_hw_event {
  108. /*
  109. * The MSB of the config word signifies if the rest contains cpu
  110. * specific (raw) counter configuration data, if unset, the next
  111. * 7 bits are an event type and the rest of the bits are the event
  112. * identifier.
  113. */
  114. __u64 config;
  115. union {
  116. __u64 irq_period;
  117. __u64 irq_freq;
  118. };
  119. __u32 record_type;
  120. __u32 read_format;
  121. __u64 disabled : 1, /* off by default */
  122. nmi : 1, /* NMI sampling */
  123. inherit : 1, /* children inherit it */
  124. pinned : 1, /* must always be on PMU */
  125. exclusive : 1, /* only group on PMU */
  126. exclude_user : 1, /* don't count user */
  127. exclude_kernel : 1, /* ditto kernel */
  128. exclude_hv : 1, /* ditto hypervisor */
  129. exclude_idle : 1, /* don't count when idle */
  130. mmap : 1, /* include mmap data */
  131. munmap : 1, /* include munmap data */
  132. comm : 1, /* include comm data */
  133. freq : 1, /* use freq, not period */
  134. __reserved_1 : 51;
  135. __u32 wakeup_events; /* wakeup every n events */
  136. __u32 __reserved_2;
  137. __u64 __reserved_3;
  138. __u64 __reserved_4;
  139. };
  140. /*
  141. * Ioctls that can be done on a perf counter fd:
  142. */
  143. #define PERF_COUNTER_IOC_ENABLE _IOW('$', 0, u32)
  144. #define PERF_COUNTER_IOC_DISABLE _IOW('$', 1, u32)
  145. #define PERF_COUNTER_IOC_REFRESH _IOW('$', 2, u32)
  146. #define PERF_COUNTER_IOC_RESET _IOW('$', 3, u32)
  147. enum perf_counter_ioc_flags {
  148. PERF_IOC_FLAG_GROUP = 1U << 0,
  149. };
  150. /*
  151. * Structure of the page that can be mapped via mmap
  152. */
  153. struct perf_counter_mmap_page {
  154. __u32 version; /* version number of this structure */
  155. __u32 compat_version; /* lowest version this is compat with */
  156. /*
  157. * Bits needed to read the hw counters in user-space.
  158. *
  159. * u32 seq;
  160. * s64 count;
  161. *
  162. * do {
  163. * seq = pc->lock;
  164. *
  165. * barrier()
  166. * if (pc->index) {
  167. * count = pmc_read(pc->index - 1);
  168. * count += pc->offset;
  169. * } else
  170. * goto regular_read;
  171. *
  172. * barrier();
  173. * } while (pc->lock != seq);
  174. *
  175. * NOTE: for obvious reason this only works on self-monitoring
  176. * processes.
  177. */
  178. __u32 lock; /* seqlock for synchronization */
  179. __u32 index; /* hardware counter identifier */
  180. __s64 offset; /* add to hardware counter value */
  181. /*
  182. * Control data for the mmap() data buffer.
  183. *
  184. * User-space reading this value should issue an rmb(), on SMP capable
  185. * platforms, after reading this value -- see perf_counter_wakeup().
  186. */
  187. __u32 data_head; /* head in the data section */
  188. };
  189. #define PERF_EVENT_MISC_CPUMODE_MASK (3 << 0)
  190. #define PERF_EVENT_MISC_CPUMODE_UNKNOWN (0 << 0)
  191. #define PERF_EVENT_MISC_KERNEL (1 << 0)
  192. #define PERF_EVENT_MISC_USER (2 << 0)
  193. #define PERF_EVENT_MISC_HYPERVISOR (3 << 0)
  194. #define PERF_EVENT_MISC_OVERFLOW (1 << 2)
  195. struct perf_event_header {
  196. __u32 type;
  197. __u16 misc;
  198. __u16 size;
  199. };
  200. enum perf_event_type {
  201. /*
  202. * The MMAP events record the PROT_EXEC mappings so that we can
  203. * correlate userspace IPs to code. They have the following structure:
  204. *
  205. * struct {
  206. * struct perf_event_header header;
  207. *
  208. * u32 pid, tid;
  209. * u64 addr;
  210. * u64 len;
  211. * u64 pgoff;
  212. * char filename[];
  213. * };
  214. */
  215. PERF_EVENT_MMAP = 1,
  216. PERF_EVENT_MUNMAP = 2,
  217. /*
  218. * struct {
  219. * struct perf_event_header header;
  220. *
  221. * u32 pid, tid;
  222. * char comm[];
  223. * };
  224. */
  225. PERF_EVENT_COMM = 3,
  226. /*
  227. * struct {
  228. * struct perf_event_header header;
  229. * u64 time;
  230. * u64 irq_period;
  231. * };
  232. */
  233. PERF_EVENT_PERIOD = 4,
  234. /*
  235. * struct {
  236. * struct perf_event_header header;
  237. * u64 time;
  238. * };
  239. */
  240. PERF_EVENT_THROTTLE = 5,
  241. PERF_EVENT_UNTHROTTLE = 6,
  242. /*
  243. * When header.misc & PERF_EVENT_MISC_OVERFLOW the event_type field
  244. * will be PERF_RECORD_*
  245. *
  246. * struct {
  247. * struct perf_event_header header;
  248. *
  249. * { u64 ip; } && PERF_RECORD_IP
  250. * { u32 pid, tid; } && PERF_RECORD_TID
  251. * { u64 time; } && PERF_RECORD_TIME
  252. * { u64 addr; } && PERF_RECORD_ADDR
  253. * { u64 config; } && PERF_RECORD_CONFIG
  254. * { u32 cpu, res; } && PERF_RECORD_CPU
  255. *
  256. * { u64 nr;
  257. * { u64 event, val; } cnt[nr]; } && PERF_RECORD_GROUP
  258. *
  259. * { u16 nr,
  260. * hv,
  261. * kernel,
  262. * user;
  263. * u64 ips[nr]; } && PERF_RECORD_CALLCHAIN
  264. * };
  265. */
  266. };
  267. #ifdef __KERNEL__
  268. /*
  269. * Kernel-internal data types and definitions:
  270. */
  271. #ifdef CONFIG_PERF_COUNTERS
  272. # include <asm/perf_counter.h>
  273. #endif
  274. #include <linux/list.h>
  275. #include <linux/mutex.h>
  276. #include <linux/rculist.h>
  277. #include <linux/rcupdate.h>
  278. #include <linux/spinlock.h>
  279. #include <linux/hrtimer.h>
  280. #include <linux/fs.h>
  281. #include <asm/atomic.h>
  282. struct task_struct;
  283. static inline u64 perf_event_raw(struct perf_counter_hw_event *hw_event)
  284. {
  285. return hw_event->config & PERF_COUNTER_RAW_MASK;
  286. }
  287. static inline u64 perf_event_config(struct perf_counter_hw_event *hw_event)
  288. {
  289. return hw_event->config & PERF_COUNTER_CONFIG_MASK;
  290. }
  291. static inline u64 perf_event_type(struct perf_counter_hw_event *hw_event)
  292. {
  293. return (hw_event->config & PERF_COUNTER_TYPE_MASK) >>
  294. PERF_COUNTER_TYPE_SHIFT;
  295. }
  296. static inline u64 perf_event_id(struct perf_counter_hw_event *hw_event)
  297. {
  298. return hw_event->config & PERF_COUNTER_EVENT_MASK;
  299. }
  300. /**
  301. * struct hw_perf_counter - performance counter hardware details:
  302. */
  303. struct hw_perf_counter {
  304. #ifdef CONFIG_PERF_COUNTERS
  305. union {
  306. struct { /* hardware */
  307. u64 config;
  308. unsigned long config_base;
  309. unsigned long counter_base;
  310. int nmi;
  311. int idx;
  312. };
  313. union { /* software */
  314. atomic64_t count;
  315. struct hrtimer hrtimer;
  316. };
  317. };
  318. atomic64_t prev_count;
  319. u64 irq_period;
  320. atomic64_t period_left;
  321. u64 interrupts;
  322. #endif
  323. };
  324. struct perf_counter;
  325. /**
  326. * struct pmu - generic performance monitoring unit
  327. */
  328. struct pmu {
  329. int (*enable) (struct perf_counter *counter);
  330. void (*disable) (struct perf_counter *counter);
  331. void (*read) (struct perf_counter *counter);
  332. void (*unthrottle) (struct perf_counter *counter);
  333. };
  334. /**
  335. * enum perf_counter_active_state - the states of a counter
  336. */
  337. enum perf_counter_active_state {
  338. PERF_COUNTER_STATE_ERROR = -2,
  339. PERF_COUNTER_STATE_OFF = -1,
  340. PERF_COUNTER_STATE_INACTIVE = 0,
  341. PERF_COUNTER_STATE_ACTIVE = 1,
  342. };
  343. struct file;
  344. struct perf_mmap_data {
  345. struct rcu_head rcu_head;
  346. int nr_pages; /* nr of data pages */
  347. int nr_locked; /* nr pages mlocked */
  348. atomic_t poll; /* POLL_ for wakeups */
  349. atomic_t head; /* write position */
  350. atomic_t events; /* event limit */
  351. atomic_t done_head; /* completed head */
  352. atomic_t lock; /* concurrent writes */
  353. atomic_t wakeup; /* needs a wakeup */
  354. struct perf_counter_mmap_page *user_page;
  355. void *data_pages[0];
  356. };
  357. struct perf_pending_entry {
  358. struct perf_pending_entry *next;
  359. void (*func)(struct perf_pending_entry *);
  360. };
  361. /**
  362. * struct perf_counter - performance counter kernel representation:
  363. */
  364. struct perf_counter {
  365. #ifdef CONFIG_PERF_COUNTERS
  366. struct list_head list_entry;
  367. struct list_head event_entry;
  368. struct list_head sibling_list;
  369. int nr_siblings;
  370. struct perf_counter *group_leader;
  371. const struct pmu *pmu;
  372. enum perf_counter_active_state state;
  373. enum perf_counter_active_state prev_state;
  374. atomic64_t count;
  375. /*
  376. * These are the total time in nanoseconds that the counter
  377. * has been enabled (i.e. eligible to run, and the task has
  378. * been scheduled in, if this is a per-task counter)
  379. * and running (scheduled onto the CPU), respectively.
  380. *
  381. * They are computed from tstamp_enabled, tstamp_running and
  382. * tstamp_stopped when the counter is in INACTIVE or ACTIVE state.
  383. */
  384. u64 total_time_enabled;
  385. u64 total_time_running;
  386. /*
  387. * These are timestamps used for computing total_time_enabled
  388. * and total_time_running when the counter is in INACTIVE or
  389. * ACTIVE state, measured in nanoseconds from an arbitrary point
  390. * in time.
  391. * tstamp_enabled: the notional time when the counter was enabled
  392. * tstamp_running: the notional time when the counter was scheduled on
  393. * tstamp_stopped: in INACTIVE state, the notional time when the
  394. * counter was scheduled off.
  395. */
  396. u64 tstamp_enabled;
  397. u64 tstamp_running;
  398. u64 tstamp_stopped;
  399. struct perf_counter_hw_event hw_event;
  400. struct hw_perf_counter hw;
  401. struct perf_counter_context *ctx;
  402. struct file *filp;
  403. /*
  404. * These accumulate total time (in nanoseconds) that children
  405. * counters have been enabled and running, respectively.
  406. */
  407. atomic64_t child_total_time_enabled;
  408. atomic64_t child_total_time_running;
  409. /*
  410. * Protect attach/detach and child_list:
  411. */
  412. struct mutex child_mutex;
  413. struct list_head child_list;
  414. struct perf_counter *parent;
  415. int oncpu;
  416. int cpu;
  417. struct list_head owner_entry;
  418. struct task_struct *owner;
  419. /* mmap bits */
  420. struct mutex mmap_mutex;
  421. atomic_t mmap_count;
  422. struct perf_mmap_data *data;
  423. /* poll related */
  424. wait_queue_head_t waitq;
  425. struct fasync_struct *fasync;
  426. /* delayed work for NMIs and such */
  427. int pending_wakeup;
  428. int pending_kill;
  429. int pending_disable;
  430. struct perf_pending_entry pending;
  431. atomic_t event_limit;
  432. void (*destroy)(struct perf_counter *);
  433. struct rcu_head rcu_head;
  434. #endif
  435. };
  436. /**
  437. * struct perf_counter_context - counter context structure
  438. *
  439. * Used as a container for task counters and CPU counters as well:
  440. */
  441. struct perf_counter_context {
  442. /*
  443. * Protect the states of the counters in the list,
  444. * nr_active, and the list:
  445. */
  446. spinlock_t lock;
  447. /*
  448. * Protect the list of counters. Locking either mutex or lock
  449. * is sufficient to ensure the list doesn't change; to change
  450. * the list you need to lock both the mutex and the spinlock.
  451. */
  452. struct mutex mutex;
  453. struct list_head counter_list;
  454. struct list_head event_list;
  455. int nr_counters;
  456. int nr_active;
  457. int is_active;
  458. atomic_t refcount;
  459. struct task_struct *task;
  460. /*
  461. * Context clock, runs when context enabled.
  462. */
  463. u64 time;
  464. u64 timestamp;
  465. /*
  466. * These fields let us detect when two contexts have both
  467. * been cloned (inherited) from a common ancestor.
  468. */
  469. struct perf_counter_context *parent_ctx;
  470. u64 parent_gen;
  471. u64 generation;
  472. struct rcu_head rcu_head;
  473. };
  474. /**
  475. * struct perf_counter_cpu_context - per cpu counter context structure
  476. */
  477. struct perf_cpu_context {
  478. struct perf_counter_context ctx;
  479. struct perf_counter_context *task_ctx;
  480. int active_oncpu;
  481. int max_pertask;
  482. int exclusive;
  483. /*
  484. * Recursion avoidance:
  485. *
  486. * task, softirq, irq, nmi context
  487. */
  488. int recursion[4];
  489. };
  490. #ifdef CONFIG_PERF_COUNTERS
  491. /*
  492. * Set by architecture code:
  493. */
  494. extern int perf_max_counters;
  495. extern const struct pmu *hw_perf_counter_init(struct perf_counter *counter);
  496. extern void perf_counter_task_sched_in(struct task_struct *task, int cpu);
  497. extern void perf_counter_task_sched_out(struct task_struct *task,
  498. struct task_struct *next, int cpu);
  499. extern void perf_counter_task_tick(struct task_struct *task, int cpu);
  500. extern int perf_counter_init_task(struct task_struct *child);
  501. extern void perf_counter_exit_task(struct task_struct *child);
  502. extern void perf_counter_free_task(struct task_struct *task);
  503. extern void perf_counter_do_pending(void);
  504. extern void perf_counter_print_debug(void);
  505. extern void __perf_disable(void);
  506. extern bool __perf_enable(void);
  507. extern void perf_disable(void);
  508. extern void perf_enable(void);
  509. extern int perf_counter_task_disable(void);
  510. extern int perf_counter_task_enable(void);
  511. extern int hw_perf_group_sched_in(struct perf_counter *group_leader,
  512. struct perf_cpu_context *cpuctx,
  513. struct perf_counter_context *ctx, int cpu);
  514. extern void perf_counter_update_userpage(struct perf_counter *counter);
  515. extern int perf_counter_overflow(struct perf_counter *counter,
  516. int nmi, struct pt_regs *regs, u64 addr);
  517. /*
  518. * Return 1 for a software counter, 0 for a hardware counter
  519. */
  520. static inline int is_software_counter(struct perf_counter *counter)
  521. {
  522. return !perf_event_raw(&counter->hw_event) &&
  523. perf_event_type(&counter->hw_event) != PERF_TYPE_HARDWARE;
  524. }
  525. extern void perf_swcounter_event(u32, u64, int, struct pt_regs *, u64);
  526. extern void perf_counter_mmap(unsigned long addr, unsigned long len,
  527. unsigned long pgoff, struct file *file);
  528. extern void perf_counter_munmap(unsigned long addr, unsigned long len,
  529. unsigned long pgoff, struct file *file);
  530. extern void perf_counter_comm(struct task_struct *tsk);
  531. #define MAX_STACK_DEPTH 255
  532. struct perf_callchain_entry {
  533. u16 nr, hv, kernel, user;
  534. u64 ip[MAX_STACK_DEPTH];
  535. };
  536. extern struct perf_callchain_entry *perf_callchain(struct pt_regs *regs);
  537. extern int sysctl_perf_counter_priv;
  538. extern int sysctl_perf_counter_mlock;
  539. extern int sysctl_perf_counter_limit;
  540. extern void perf_counter_init(void);
  541. #ifndef perf_misc_flags
  542. #define perf_misc_flags(regs) (user_mode(regs) ? PERF_EVENT_MISC_USER : \
  543. PERF_EVENT_MISC_KERNEL)
  544. #define perf_instruction_pointer(regs) instruction_pointer(regs)
  545. #endif
  546. #else
  547. static inline void
  548. perf_counter_task_sched_in(struct task_struct *task, int cpu) { }
  549. static inline void
  550. perf_counter_task_sched_out(struct task_struct *task,
  551. struct task_struct *next, int cpu) { }
  552. static inline void
  553. perf_counter_task_tick(struct task_struct *task, int cpu) { }
  554. static inline int perf_counter_init_task(struct task_struct *child) { return 0; }
  555. static inline void perf_counter_exit_task(struct task_struct *child) { }
  556. static inline void perf_counter_free_task(struct task_struct *task) { }
  557. static inline void perf_counter_do_pending(void) { }
  558. static inline void perf_counter_print_debug(void) { }
  559. static inline void perf_disable(void) { }
  560. static inline void perf_enable(void) { }
  561. static inline int perf_counter_task_disable(void) { return -EINVAL; }
  562. static inline int perf_counter_task_enable(void) { return -EINVAL; }
  563. static inline void
  564. perf_swcounter_event(u32 event, u64 nr, int nmi,
  565. struct pt_regs *regs, u64 addr) { }
  566. static inline void
  567. perf_counter_mmap(unsigned long addr, unsigned long len,
  568. unsigned long pgoff, struct file *file) { }
  569. static inline void
  570. perf_counter_munmap(unsigned long addr, unsigned long len,
  571. unsigned long pgoff, struct file *file) { }
  572. static inline void perf_counter_comm(struct task_struct *tsk) { }
  573. static inline void perf_counter_init(void) { }
  574. #endif
  575. #endif /* __KERNEL__ */
  576. #endif /* _LINUX_PERF_COUNTER_H */