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 <asm/atomic.h>
  17
  18 #include <linux/list.h>
  19 #include <linux/mutex.h>
  20 #include <linux/rculist.h>
  21 #include <linux/rcupdate.h>
  22 #include <linux/spinlock.h>
  23
  24 struct task_struct;
  25
  26 /*
  27  * Generalized hardware event types, used by the hw_event_type parameter
  28  * of the sys_perf_counter_open() syscall:
  29  */
  30 enum hw_event_types {
  31         PERF_COUNT_CYCLES,
  32         PERF_COUNT_INSTRUCTIONS,
  33         PERF_COUNT_CACHE_REFERENCES,
  34         PERF_COUNT_CACHE_MISSES,
  35         PERF_COUNT_BRANCH_INSTRUCTIONS,
  36         PERF_COUNT_BRANCH_MISSES,
  37         /*
  38          * If this bit is set in the type, then trigger NMI sampling:
  39          */
  40         PERF_COUNT_NMI                  = (1 << 30),
  41 };
  42
  43 /*
  44  * IRQ-notification data record type:
  45  */
  46 enum perf_record_type {
  47         PERF_RECORD_SIMPLE,
  48         PERF_RECORD_IRQ,
  49         PERF_RECORD_GROUP,
  50 };
  51
  52 /**
  53  * struct hw_perf_counter - performance counter hardware details
  54  */
  55 struct hw_perf_counter {
  56         u64                     config;
  57         unsigned long           config_base;
  58         unsigned long           counter_base;
  59         int                     nmi;
  60         unsigned int            idx;
  61         u64                     prev_count;
  62         s32                     next_count;
  63         u64                     irq_period;
  64 };
  65
  66 /*
  67  * Hardcoded buffer length limit for now, for IRQ-fed events:
  68  */
  69 #define PERF_DATA_BUFLEN        2048
  70
  71 /**
  72  * struct perf_data - performance counter IRQ data sampling ...
  73  */
  74 struct perf_data {
  75         int                     len;
  76         int                     rd_idx;
  77         int                     overrun;
  78         u8                      data[PERF_DATA_BUFLEN];
  79 };
  80
  81 /**
  82  * struct perf_counter - performance counter kernel representation:
  83  */
  84 struct perf_counter {
  85         struct list_head                list;
  86         int                             active;
  87 #if BITS_PER_LONG == 64
  88         atomic64_t                      count;
  89 #else
  90         atomic_t                        count32[2];
  91 #endif
  92         u64                             __irq_period;
  93
  94         struct hw_perf_counter          hw;
  95
  96         struct perf_counter_context     *ctx;
  97         struct task_struct              *task;
  98
  99         /*
 100          * Protect attach/detach:
 101          */
 102         struct mutex                    mutex;
 103
 104         int                             oncpu;
 105         int                             cpu;
 106
 107         s32                             hw_event_type;
 108         enum perf_record_type           record_type;
 109
 110         /* read() / irq related data */
 111         wait_queue_head_t               waitq;
 112         /* optional: for NMIs */
 113         int                             wakeup_pending;
 114         struct perf_data                *irqdata;
 115         struct perf_data                *usrdata;
 116         struct perf_data                data[2];
 117 };
 118
 119 /**
 120  * struct perf_counter_context - counter context structure
 121  *
 122  * Used as a container for task counters and CPU counters as well:
 123  */
 124 struct perf_counter_context {
 125 #ifdef CONFIG_PERF_COUNTERS
 126         /*
 127          * Protect the list of counters:
 128          */
 129         spinlock_t              lock;
 130         struct list_head        counters;
 131         int                     nr_counters;
 132         int                     nr_active;
 133         struct task_struct      *task;
 134 #endif
 135 };
 136
 137 /**
 138  * struct perf_counter_cpu_context - per cpu counter context structure
 139  */
 140 struct perf_cpu_context {
 141         struct perf_counter_context     ctx;
 142         struct perf_counter_context     *task_ctx;
 143         int                             active_oncpu;
 144         int                             max_pertask;
 145 };
 146
 147 /*
 148  * Set by architecture code:
 149  */
 150 extern int perf_max_counters;
 151
 152 #ifdef CONFIG_PERF_COUNTERS
 153 extern void perf_counter_task_sched_in(struct task_struct *task, int cpu);
 154 extern void perf_counter_task_sched_out(struct task_struct *task, int cpu);
 155 extern void perf_counter_task_tick(struct task_struct *task, int cpu);
 156 extern void perf_counter_init_task(struct task_struct *task);
 157 extern void perf_counter_notify(struct pt_regs *regs);
 158 extern void perf_counter_print_debug(void);
 159 #else
 160 static inline void
 161 perf_counter_task_sched_in(struct task_struct *task, int cpu)           { }
 162 static inline void
 163 perf_counter_task_sched_out(struct task_struct *task, int cpu)          { }
 164 static inline void
 165 perf_counter_task_tick(struct task_struct *task, int cpu)               { }
 166 static inline void perf_counter_init_task(struct task_struct *task)     { }
 167 static inline void perf_counter_notify(struct pt_regs *regs)            { }
 168 static inline void perf_counter_print_debug(void)                       { }
 169 #endif
 170
 171 #endif /* _LINUX_PERF_COUNTER_H */