2 * Performance counters:
4 * Copyright(C) 2008, Thomas Gleixner <tglx@linutronix.de>
5 * Copyright(C) 2008, Red Hat, Inc., Ingo Molnar
7 * Data type definitions, declarations, prototypes.
9 * Started by: Thomas Gleixner and Ingo Molnar
11 * For licencing details see kernel-base/COPYING
13 #ifndef _LINUX_PERF_COUNTER_H
14 #define _LINUX_PERF_COUNTER_H
16 #include <asm/atomic.h>
17 #include <asm/ioctl.h>
19 #ifdef CONFIG_PERF_COUNTERS
20 # include <asm/perf_counter.h>
23 #include <linux/list.h>
24 #include <linux/mutex.h>
25 #include <linux/rculist.h>
26 #include <linux/rcupdate.h>
27 #include <linux/spinlock.h>
32 * User-space ABI bits:
36 * Generalized performance counter event types, used by the hw_event.type
37 * parameter of the sys_perf_counter_open() syscall:
41 * Common hardware events, generalized by the kernel:
43 PERF_COUNT_CPU_CYCLES
= 0,
44 PERF_COUNT_INSTRUCTIONS
= 1,
45 PERF_COUNT_CACHE_REFERENCES
= 2,
46 PERF_COUNT_CACHE_MISSES
= 3,
47 PERF_COUNT_BRANCH_INSTRUCTIONS
= 4,
48 PERF_COUNT_BRANCH_MISSES
= 5,
49 PERF_COUNT_BUS_CYCLES
= 6,
51 PERF_HW_EVENTS_MAX
= 7,
54 * Special "software" counters provided by the kernel, even if
55 * the hardware does not support performance counters. These
56 * counters measure various physical and sw events of the
57 * kernel (and allow the profiling of them as well):
59 PERF_COUNT_CPU_CLOCK
= -1,
60 PERF_COUNT_TASK_CLOCK
= -2,
61 PERF_COUNT_PAGE_FAULTS
= -3,
62 PERF_COUNT_CONTEXT_SWITCHES
= -4,
63 PERF_COUNT_CPU_MIGRATIONS
= -5,
65 PERF_SW_EVENTS_MIN
= -6,
69 * IRQ-notification data record type:
71 enum perf_counter_record_type
{
72 PERF_RECORD_SIMPLE
= 0,
74 PERF_RECORD_GROUP
= 2,
78 * Hardware event to monitor via a performance monitoring counter:
80 struct perf_counter_hw_event
{
86 u32 disabled
: 1, /* off by default */
87 nmi
: 1, /* NMI sampling */
88 raw
: 1, /* raw event type */
89 inherit
: 1, /* children inherit it */
90 pinned
: 1, /* must always be on PMU */
91 exclusive
: 1, /* only counter on PMU */
99 * Ioctls that can be done on a perf counter fd:
101 #define PERF_COUNTER_IOC_ENABLE _IO('$', 0)
102 #define PERF_COUNTER_IOC_DISABLE _IO('$', 1)
105 * Kernel-internal data types:
109 * struct hw_perf_counter - performance counter hardware details:
111 struct hw_perf_counter
{
112 #ifdef CONFIG_PERF_COUNTERS
114 unsigned long config_base
;
115 unsigned long counter_base
;
118 atomic64_t prev_count
;
120 atomic64_t period_left
;
125 * Hardcoded buffer length limit for now, for IRQ-fed events:
127 #define PERF_DATA_BUFLEN 2048
130 * struct perf_data - performance counter IRQ data sampling ...
136 u8 data
[PERF_DATA_BUFLEN
];
142 * struct hw_perf_counter_ops - performance counter hw ops
144 struct hw_perf_counter_ops
{
145 int (*enable
) (struct perf_counter
*counter
);
146 void (*disable
) (struct perf_counter
*counter
);
147 void (*read
) (struct perf_counter
*counter
);
151 * enum perf_counter_active_state - the states of a counter
153 enum perf_counter_active_state
{
154 PERF_COUNTER_STATE_ERROR
= -2,
155 PERF_COUNTER_STATE_OFF
= -1,
156 PERF_COUNTER_STATE_INACTIVE
= 0,
157 PERF_COUNTER_STATE_ACTIVE
= 1,
163 * struct perf_counter - performance counter kernel representation:
165 struct perf_counter
{
166 #ifdef CONFIG_PERF_COUNTERS
167 struct list_head list_entry
;
168 struct list_head sibling_list
;
169 struct perf_counter
*group_leader
;
170 const struct hw_perf_counter_ops
*hw_ops
;
172 enum perf_counter_active_state state
;
175 struct perf_counter_hw_event hw_event
;
176 struct hw_perf_counter hw
;
178 struct perf_counter_context
*ctx
;
179 struct task_struct
*task
;
182 struct perf_counter
*parent
;
183 struct list_head child_list
;
186 * Protect attach/detach and child_list:
193 /* read() / irq related data */
194 wait_queue_head_t waitq
;
195 /* optional: for NMIs */
197 struct perf_data
*irqdata
;
198 struct perf_data
*usrdata
;
199 struct perf_data data
[2];
204 * struct perf_counter_context - counter context structure
206 * Used as a container for task counters and CPU counters as well:
208 struct perf_counter_context
{
209 #ifdef CONFIG_PERF_COUNTERS
211 * Protect the states of the counters in the list,
212 * nr_active, and the list:
216 * Protect the list of counters. Locking either mutex or lock
217 * is sufficient to ensure the list doesn't change; to change
218 * the list you need to lock both the mutex and the spinlock.
222 struct list_head counter_list
;
226 struct task_struct
*task
;
231 * struct perf_counter_cpu_context - per cpu counter context structure
233 struct perf_cpu_context
{
234 struct perf_counter_context ctx
;
235 struct perf_counter_context
*task_ctx
;
242 * Set by architecture code:
244 extern int perf_max_counters
;
246 #ifdef CONFIG_PERF_COUNTERS
247 extern const struct hw_perf_counter_ops
*
248 hw_perf_counter_init(struct perf_counter
*counter
);
250 extern void perf_counter_task_sched_in(struct task_struct
*task
, int cpu
);
251 extern void perf_counter_task_sched_out(struct task_struct
*task
, int cpu
);
252 extern void perf_counter_task_tick(struct task_struct
*task
, int cpu
);
253 extern void perf_counter_init_task(struct task_struct
*child
);
254 extern void perf_counter_exit_task(struct task_struct
*child
);
255 extern void perf_counter_notify(struct pt_regs
*regs
);
256 extern void perf_counter_print_debug(void);
257 extern void perf_counter_unthrottle(void);
258 extern u64
hw_perf_save_disable(void);
259 extern void hw_perf_restore(u64 ctrl
);
260 extern int perf_counter_task_disable(void);
261 extern int perf_counter_task_enable(void);
262 extern int hw_perf_group_sched_in(struct perf_counter
*group_leader
,
263 struct perf_cpu_context
*cpuctx
,
264 struct perf_counter_context
*ctx
, int cpu
);
267 * Return 1 for a software counter, 0 for a hardware counter
269 static inline int is_software_counter(struct perf_counter
*counter
)
271 return !counter
->hw_event
.raw
&& counter
->hw_event
.type
< 0;
274 #define PERFMON_MIN_PERIOD_NS 10000
278 perf_counter_task_sched_in(struct task_struct
*task
, int cpu
) { }
280 perf_counter_task_sched_out(struct task_struct
*task
, int cpu
) { }
282 perf_counter_task_tick(struct task_struct
*task
, int cpu
) { }
283 static inline void perf_counter_init_task(struct task_struct
*child
) { }
284 static inline void perf_counter_exit_task(struct task_struct
*child
) { }
285 static inline void perf_counter_notify(struct pt_regs
*regs
) { }
286 static inline void perf_counter_print_debug(void) { }
287 static inline void perf_counter_unthrottle(void) { }
288 static inline void hw_perf_restore(u64 ctrl
) { }
289 static inline u64
hw_perf_save_disable(void) { return 0; }
290 static inline int perf_counter_task_disable(void) { return -EINVAL
; }
291 static inline int perf_counter_task_enable(void) { return -EINVAL
; }
294 #endif /* _LINUX_PERF_COUNTER_H */