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
  19 /*
  20  * User-space ABI bits:
  21  */
  22
  23 /*
  24  * hw_event.type
  25  */
  26 enum perf_event_types {
  27         PERF_TYPE_HARDWARE              = 0,
  28         PERF_TYPE_SOFTWARE              = 1,
  29         PERF_TYPE_TRACEPOINT            = 2,
  30
  31         /*
  32          * available TYPE space, raw is the max value.
  33          */
  34
  35         PERF_TYPE_RAW                   = 128,
  36 };
  37
  38 /*
  39  * Generalized performance counter event types, used by the hw_event.event_id
  40  * parameter of the sys_perf_counter_open() syscall:
  41  */
  42 enum hw_event_ids {
  43         /*
  44          * Common hardware events, generalized by the kernel:
  45          */
  46         PERF_COUNT_CPU_CYCLES           = 0,
  47         PERF_COUNT_INSTRUCTIONS         = 1,
  48         PERF_COUNT_CACHE_REFERENCES     = 2,
  49         PERF_COUNT_CACHE_MISSES         = 3,
  50         PERF_COUNT_BRANCH_INSTRUCTIONS  = 4,
  51         PERF_COUNT_BRANCH_MISSES        = 5,
  52         PERF_COUNT_BUS_CYCLES           = 6,
  53
  54         PERF_HW_EVENTS_MAX              = 7,
  55 };
  56
  57 /*
  58  * Special "software" counters provided by the kernel, even if the hardware
  59  * does not support performance counters. These counters measure various
  60  * physical and sw events of the kernel (and allow the profiling of them as
  61  * well):
  62  */
  63 enum sw_event_ids {
  64         PERF_COUNT_CPU_CLOCK            = 0,
  65         PERF_COUNT_TASK_CLOCK           = 1,
  66         PERF_COUNT_PAGE_FAULTS          = 2,
  67         PERF_COUNT_CONTEXT_SWITCHES     = 3,
  68         PERF_COUNT_CPU_MIGRATIONS       = 4,
  69         PERF_COUNT_PAGE_FAULTS_MIN      = 5,
  70         PERF_COUNT_PAGE_FAULTS_MAJ      = 6,
  71
  72         PERF_SW_EVENTS_MAX              = 7,
  73 };
  74
  75 /*
  76  * IRQ-notification data record type:
  77  */
  78 enum perf_counter_record_type {
  79         PERF_RECORD_SIMPLE              = 0,
  80         PERF_RECORD_IRQ                 = 1,
  81         PERF_RECORD_GROUP               = 2,
  82 };
  83
  84 /*
  85  * Hardware event to monitor via a performance monitoring counter:
  86  */
  87 struct perf_counter_hw_event {
  88         union {
  89                 struct {
  90                         __u64                   event_id        : 56,
  91                                                 type            :  8;
  92                 };
  93                 struct {
  94                         __u64                   raw_event_id    : 63,
  95                                                 raw_type        :  1;
  96                 };
  97                 __u64           event_config;
  98         };
  99
 100         __u64                   irq_period;
 101         __u64                   record_type;
 102         __u64                   read_format;
 103
 104         __u64                   disabled       :  1, /* off by default        */
 105                                 nmi            :  1, /* NMI sampling          */
 106                                 inherit        :  1, /* children inherit it   */
 107                                 pinned         :  1, /* must always be on PMU */
 108                                 exclusive      :  1, /* only group on PMU     */
 109                                 exclude_user   :  1, /* don't count user      */
 110                                 exclude_kernel :  1, /* ditto kernel          */
 111                                 exclude_hv     :  1, /* ditto hypervisor      */
 112                                 exclude_idle   :  1, /* don't count when idle */
 113
 114                                 __reserved_1   : 55;
 115
 116         __u32                   extra_config_len;
 117         __u32                   __reserved_4;
 118
 119         __u64                   __reserved_2;
 120         __u64                   __reserved_3;
 121 };
 122
 123 /*
 124  * Ioctls that can be done on a perf counter fd:
 125  */
 126 #define PERF_COUNTER_IOC_ENABLE         _IO('$', 0)
 127 #define PERF_COUNTER_IOC_DISABLE        _IO('$', 1)
 128
 129 #ifdef __KERNEL__
 130 /*
 131  * Kernel-internal data types and definitions:
 132  */
 133
 134 #ifdef CONFIG_PERF_COUNTERS
 135 # include <asm/perf_counter.h>
 136 #endif
 137
 138 #include <linux/list.h>
 139 #include <linux/mutex.h>
 140 #include <linux/rculist.h>
 141 #include <linux/rcupdate.h>
 142 #include <linux/spinlock.h>
 143 #include <linux/hrtimer.h>
 144 #include <asm/atomic.h>
 145
 146 struct task_struct;
 147
 148 /**
 149  * struct hw_perf_counter - performance counter hardware details:
 150  */
 151 struct hw_perf_counter {
 152 #ifdef CONFIG_PERF_COUNTERS
 153         union {
 154                 struct { /* hardware */
 155                         u64                             config;
 156                         unsigned long                   config_base;
 157                         unsigned long                   counter_base;
 158                         int                             nmi;
 159                         unsigned int                    idx;
 160                 };
 161                 union { /* software */
 162                         atomic64_t                      count;
 163                         struct hrtimer                  hrtimer;
 164                 };
 165         };
 166         atomic64_t                      prev_count;
 167         u64                             irq_period;
 168         atomic64_t                      period_left;
 169 #endif
 170 };
 171
 172 /*
 173  * Hardcoded buffer length limit for now, for IRQ-fed events:
 174  */
 175 #define PERF_DATA_BUFLEN                2048
 176
 177 /**
 178  * struct perf_data - performance counter IRQ data sampling ...
 179  */
 180 struct perf_data {
 181         int                             len;
 182         int                             rd_idx;
 183         int                             overrun;
 184         u8                              data[PERF_DATA_BUFLEN];
 185 };
 186
 187 struct perf_counter;
 188
 189 /**
 190  * struct hw_perf_counter_ops - performance counter hw ops
 191  */
 192 struct hw_perf_counter_ops {
 193         int (*enable)                   (struct perf_counter *counter);
 194         void (*disable)                 (struct perf_counter *counter);
 195         void (*read)                    (struct perf_counter *counter);
 196 };
 197
 198 /**
 199  * enum perf_counter_active_state - the states of a counter
 200  */
 201 enum perf_counter_active_state {
 202         PERF_COUNTER_STATE_ERROR        = -2,
 203         PERF_COUNTER_STATE_OFF          = -1,
 204         PERF_COUNTER_STATE_INACTIVE     =  0,
 205         PERF_COUNTER_STATE_ACTIVE       =  1,
 206 };
 207
 208 struct file;
 209
 210 /**
 211  * struct perf_counter - performance counter kernel representation:
 212  */
 213 struct perf_counter {
 214 #ifdef CONFIG_PERF_COUNTERS
 215         struct list_head                list_entry;
 216         struct list_head                event_entry;
 217         struct list_head                sibling_list;
 218         struct perf_counter             *group_leader;
 219         const struct hw_perf_counter_ops *hw_ops;
 220
 221         enum perf_counter_active_state  state;
 222         enum perf_counter_active_state  prev_state;
 223         atomic64_t                      count;
 224
 225         struct perf_counter_hw_event    hw_event;
 226         struct hw_perf_counter          hw;
 227
 228         struct perf_counter_context     *ctx;
 229         struct task_struct              *task;
 230         struct file                     *filp;
 231
 232         struct perf_counter             *parent;
 233         struct list_head                child_list;
 234
 235         /*
 236          * Protect attach/detach and child_list:
 237          */
 238         struct mutex                    mutex;
 239
 240         int                             oncpu;
 241         int                             cpu;
 242
 243         /* read() / irq related data */
 244         wait_queue_head_t               waitq;
 245         /* optional: for NMIs */
 246         int                             wakeup_pending;
 247         struct perf_data                *irqdata;
 248         struct perf_data                *usrdata;
 249         struct perf_data                data[2];
 250
 251         void (*destroy)(struct perf_counter *);
 252         struct rcu_head                 rcu_head;
 253 #endif
 254 };
 255
 256 /**
 257  * struct perf_counter_context - counter context structure
 258  *
 259  * Used as a container for task counters and CPU counters as well:
 260  */
 261 struct perf_counter_context {
 262 #ifdef CONFIG_PERF_COUNTERS
 263         /*
 264          * Protect the states of the counters in the list,
 265          * nr_active, and the list:
 266          */
 267         spinlock_t              lock;
 268         /*
 269          * Protect the list of counters.  Locking either mutex or lock
 270          * is sufficient to ensure the list doesn't change; to change
 271          * the list you need to lock both the mutex and the spinlock.
 272          */
 273         struct mutex            mutex;
 274
 275         struct list_head        counter_list;
 276         struct list_head        event_list;
 277         int                     nr_counters;
 278         int                     nr_active;
 279         int                     is_active;
 280         struct task_struct      *task;
 281 #endif
 282 };
 283
 284 /**
 285  * struct perf_counter_cpu_context - per cpu counter context structure
 286  */
 287 struct perf_cpu_context {
 288         struct perf_counter_context     ctx;
 289         struct perf_counter_context     *task_ctx;
 290         int                             active_oncpu;
 291         int                             max_pertask;
 292         int                             exclusive;
 293 };
 294
 295 /*
 296  * Set by architecture code:
 297  */
 298 extern int perf_max_counters;
 299
 300 #ifdef CONFIG_PERF_COUNTERS
 301 extern const struct hw_perf_counter_ops *
 302 hw_perf_counter_init(struct perf_counter *counter);
 303
 304 extern void perf_counter_task_sched_in(struct task_struct *task, int cpu);
 305 extern void perf_counter_task_sched_out(struct task_struct *task, int cpu);
 306 extern void perf_counter_task_tick(struct task_struct *task, int cpu);
 307 extern void perf_counter_init_task(struct task_struct *child);
 308 extern void perf_counter_exit_task(struct task_struct *child);
 309 extern void perf_counter_notify(struct pt_regs *regs);
 310 extern void perf_counter_print_debug(void);
 311 extern void perf_counter_unthrottle(void);
 312 extern u64 hw_perf_save_disable(void);
 313 extern void hw_perf_restore(u64 ctrl);
 314 extern int perf_counter_task_disable(void);
 315 extern int perf_counter_task_enable(void);
 316 extern int hw_perf_group_sched_in(struct perf_counter *group_leader,
 317                struct perf_cpu_context *cpuctx,
 318                struct perf_counter_context *ctx, int cpu);
 319
 320 /*
 321  * Return 1 for a software counter, 0 for a hardware counter
 322  */
 323 static inline int is_software_counter(struct perf_counter *counter)
 324 {
 325         return !counter->hw_event.raw_type &&
 326                 counter->hw_event.type != PERF_TYPE_HARDWARE;
 327 }
 328
 329 extern void perf_swcounter_event(u32, u64, int, struct pt_regs *);
 330
 331 #else
 332 static inline void
 333 perf_counter_task_sched_in(struct task_struct *task, int cpu)           { }
 334 static inline void
 335 perf_counter_task_sched_out(struct task_struct *task, int cpu)          { }
 336 static inline void
 337 perf_counter_task_tick(struct task_struct *task, int cpu)               { }
 338 static inline void perf_counter_init_task(struct task_struct *child)    { }
 339 static inline void perf_counter_exit_task(struct task_struct *child)    { }
 340 static inline void perf_counter_notify(struct pt_regs *regs)            { }
 341 static inline void perf_counter_print_debug(void)                       { }
 342 static inline void perf_counter_unthrottle(void)                        { }
 343 static inline void hw_perf_restore(u64 ctrl)                            { }
 344 static inline u64 hw_perf_save_disable(void)                  { return 0; }
 345 static inline int perf_counter_task_disable(void)       { return -EINVAL; }
 346 static inline int perf_counter_task_enable(void)        { return -EINVAL; }
 347
 348 static inline void perf_swcounter_event(u32 event, u64 nr,
 349                                         int nmi, struct pt_regs *regs)  { }
 350 #endif
 351
 352 #endif /* __KERNEL__ */
 353 #endif /* _LINUX_PERF_COUNTER_H */