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         PERF_COUNT_RAW                  = (1 << 31),
  42 };
  43
  44 /*
  45  * IRQ-notification data record type:
  46  */
  47 enum perf_record_type {
  48         PERF_RECORD_SIMPLE,
  49         PERF_RECORD_IRQ,
  50         PERF_RECORD_GROUP,
  51 };
  52
  53 struct perf_counter_event {
  54         u32                     hw_event_type;
  55         u32                     hw_event_period;
  56         u64                     hw_raw_ctrl;
  57 };
  58
  59 /**
  60  * struct hw_perf_counter - performance counter hardware details
  61  */
  62 struct hw_perf_counter {
  63         u64                     config;
  64         unsigned long           config_base;
  65         unsigned long           counter_base;
  66         int                     nmi;
  67         unsigned int            idx;
  68         u64                     prev_count;
  69         s32                     next_count;
  70         u64                     irq_period;
  71 };
  72
  73 /*
  74  * Hardcoded buffer length limit for now, for IRQ-fed events:
  75  */
  76 #define PERF_DATA_BUFLEN        2048
  77
  78 /**
  79  * struct perf_data - performance counter IRQ data sampling ...
  80  */
  81 struct perf_data {
  82         int                     len;
  83         int                     rd_idx;
  84         int                     overrun;
  85         u8                      data[PERF_DATA_BUFLEN];
  86 };
  87
  88 /**
  89  * struct perf_counter - performance counter kernel representation:
  90  */
  91 struct perf_counter {
  92         struct list_head                list;
  93         int                             active;
  94 #if BITS_PER_LONG == 64
  95         atomic64_t                      count;
  96 #else
  97         atomic_t                        count32[2];
  98 #endif
  99         u64                             __irq_period;
 100
 101         struct hw_perf_counter          hw;
 102
 103         struct perf_counter_context     *ctx;
 104         struct task_struct              *task;
 105
 106         /*
 107          * Protect attach/detach:
 108          */
 109         struct mutex                    mutex;
 110
 111         int                             oncpu;
 112         int                             cpu;
 113
 114         s32                             hw_event_type;
 115         enum perf_record_type           record_type;
 116
 117         /* read() / irq related data */
 118         wait_queue_head_t               waitq;
 119         /* optional: for NMIs */
 120         int                             wakeup_pending;
 121         struct perf_data                *irqdata;
 122         struct perf_data                *usrdata;
 123         struct perf_data                data[2];
 124 };
 125
 126 /**
 127  * struct perf_counter_context - counter context structure
 128  *
 129  * Used as a container for task counters and CPU counters as well:
 130  */
 131 struct perf_counter_context {
 132 #ifdef CONFIG_PERF_COUNTERS
 133         /*
 134          * Protect the list of counters:
 135          */
 136         spinlock_t              lock;
 137         struct list_head        counters;
 138         int                     nr_counters;
 139         int                     nr_active;
 140         struct task_struct      *task;
 141 #endif
 142 };
 143
 144 /**
 145  * struct perf_counter_cpu_context - per cpu counter context structure
 146  */
 147 struct perf_cpu_context {
 148         struct perf_counter_context     ctx;
 149         struct perf_counter_context     *task_ctx;
 150         int                             active_oncpu;
 151         int                             max_pertask;
 152 };
 153
 154 /*
 155  * Set by architecture code:
 156  */
 157 extern int perf_max_counters;
 158
 159 #ifdef CONFIG_PERF_COUNTERS
 160 extern void perf_counter_task_sched_in(struct task_struct *task, int cpu);
 161 extern void perf_counter_task_sched_out(struct task_struct *task, int cpu);
 162 extern void perf_counter_task_tick(struct task_struct *task, int cpu);
 163 extern void perf_counter_init_task(struct task_struct *task);
 164 extern void perf_counter_notify(struct pt_regs *regs);
 165 extern void perf_counter_print_debug(void);
 166 extern void hw_perf_restore_ctrl(u64 ctrl);
 167 extern u64 hw_perf_disable_all(void);
 168 #else
 169 static inline void
 170 perf_counter_task_sched_in(struct task_struct *task, int cpu)           { }
 171 static inline void
 172 perf_counter_task_sched_out(struct task_struct *task, int cpu)          { }
 173 static inline void
 174 perf_counter_task_tick(struct task_struct *task, int cpu)               { }
 175 static inline void perf_counter_init_task(struct task_struct *task)     { }
 176 static inline void perf_counter_notify(struct pt_regs *regs)            { }
 177 static inline void perf_counter_print_debug(void)                       { }
 178 static inline void hw_perf_restore_ctrl(u64 ctrl)                       { }
 179 static inline u64 hw_perf_disable_all(void)             { return 0; }
 180 #endif
 181
 182 #endif /* _LINUX_PERF_COUNTER_H */