/*
* Performance counters:
*
* Copyright(C) 2008, Thomas Gleixner <tglx@linutronix.de>
* Copyright(C) 2008, Red Hat, Inc., Ingo Molnar
*
* Data type definitions, declarations, prototypes.
*
* Started by: Thomas Gleixner and Ingo Molnar
*
* For licencing details see kernel-base/COPYING
*/
#ifndef _LINUX_PERF_COUNTER_H
#define _LINUX_PERF_COUNTER_H
#include <linux/types.h>
#include <linux/ioctl.h>
#include <asm/byteorder.h>
/*
* User-space ABI bits:
*/
/*
* hw_event.type
*/
enum perf_event_types {
PERF_TYPE_HARDWARE = 0,
PERF_TYPE_SOFTWARE = 1,
PERF_TYPE_TRACEPOINT = 2,
/*
* available TYPE space, raw is the max value.
*/
PERF_TYPE_RAW = 128,
};
/*
* Generalized performance counter event types, used by the hw_event.event_id
* parameter of the sys_perf_counter_open() syscall:
*/
enum hw_event_ids {
/*
* Common hardware events, generalized by the kernel:
*/
PERF_COUNT_CPU_CYCLES = 0,
PERF_COUNT_INSTRUCTIONS = 1,
PERF_COUNT_CACHE_REFERENCES = 2,
PERF_COUNT_CACHE_MISSES = 3,
PERF_COUNT_BRANCH_INSTRUCTIONS = 4,
PERF_COUNT_BRANCH_MISSES = 5,
PERF_COUNT_BUS_CYCLES = 6,
PERF_HW_EVENTS_MAX = 7,
};
/*
* Special "software" counters provided by the kernel, even if the hardware
* does not support performance counters. These counters measure various
* physical and sw events of the kernel (and allow the profiling of them as
* well):
*/
enum sw_event_ids {
PERF_COUNT_CPU_CLOCK = 0,
PERF_COUNT_TASK_CLOCK = 1,
PERF_COUNT_PAGE_FAULTS = 2,
PERF_COUNT_CONTEXT_SWITCHES = 3,
PERF_COUNT_CPU_MIGRATIONS = 4,
PERF_COUNT_PAGE_FAULTS_MIN = 5,
PERF_COUNT_PAGE_FAULTS_MAJ = 6,
PERF_SW_EVENTS_MAX = 7,
};
#define __PERF_COUNTER_MASK(name) \
(((1ULL << PERF_COUNTER_##name##_BITS) - 1) << \
PERF_COUNTER_##name##_SHIFT)
#define PERF_COUNTER_RAW_BITS 1
#define PERF_COUNTER_RAW_SHIFT 63
#define PERF_COUNTER_RAW_MASK __PERF_COUNTER_MASK(RAW)
#define PERF_COUNTER_CONFIG_BITS 63
#define PERF_COUNTER_CONFIG_SHIFT 0
#define PERF_COUNTER_CONFIG_MASK __PERF_COUNTER_MASK(CONFIG)
#define PERF_COUNTER_TYPE_BITS 7
#define PERF_COUNTER_TYPE_SHIFT 56
#define PERF_COUNTER_TYPE_MASK __PERF_COUNTER_MASK(TYPE)
#define PERF_COUNTER_EVENT_BITS 56
#define PERF_COUNTER_EVENT_SHIFT 0
#define PERF_COUNTER_EVENT_MASK __PERF_COUNTER_MASK(EVENT)
/*
* Bits that can be set in hw_event.record_type to request information
* in the overflow packets.
*/
enum perf_counter_record_format {
PERF_RECORD_IP = 1U << 0,
PERF_RECORD_TID = 1U << 1,
PERF_RECORD_GROUP = 1U << 2,
PERF_RECORD_CALLCHAIN = 1U << 3,
};
/*
* Bits that can be set in hw_event.read_format to request that
* reads on the counter should return the indicated quantities,
* in increasing order of bit value, after the counter value.
*/
enum perf_counter_read_format {
PERF_FORMAT_TOTAL_TIME_ENABLED = 1,
PERF_FORMAT_TOTAL_TIME_RUNNING = 2,
};
/*
* Hardware event to monitor via a performance monitoring counter:
*/
struct perf_counter_hw_event {
/*
* The MSB of the config word signifies if the rest contains cpu
* specific (raw) counter configuration data, if unset, the next
* 7 bits are an event type and the rest of the bits are the event
* identifier.
*/
__u64 config;
__u64 irq_period;
__u32 record_type;
__u32 read_format;
__u64 disabled : 1, /* off by default */
nmi : 1, /* NMI sampling */
inherit : 1, /* children inherit it */
pinned : 1, /* must always be on PMU */
exclusive : 1, /* only group on PMU */
exclude_user : 1, /* don't count user */
exclude_kernel : 1, /* ditto kernel */
exclude_hv : 1, /* ditto hypervisor */
exclude_idle : 1, /* don't count when idle */
mmap : 1, /* include mmap data */
munmap : 1, /* include munmap data */
__reserved_1 : 53;
__u32 extra_config_len;
__u32 wakeup_events; /* wakeup every n events */
__u64 __reserved_2;
__u64 __reserved_3;
};
/*
* Ioctls that can be done on a perf counter fd:
*/
#define PERF_COUNTER_IOC_ENABLE _IO('$', 0)
#define PERF_COUNTER_IOC_DISABLE _IO('$', 1)
/*
* Structure of the page that can be mapped via mmap
*/
struct perf_counter_mmap_page {
__u32 version; /* version number of this structure */
__u32 compat_version; /* lowest version this is compat with */
/*
* Bits needed to read the hw counters in user-space.
*
* u32 seq;
* s64 count;
*
* again:
* seq = pc->lock;
* if (unlikely(seq & 1)) {
* cpu_relax();
* goto again;
* }
*
* if (pc->index) {
* count = pmc_read(pc->index - 1);
* count += pc->offset;
* } else
* goto regular_read;
*
* barrier();
* if (pc->lock != seq)
* goto again;
*
* NOTE: for obvious reason this only works on self-monitoring
* processes.
*/
__u32 lock; /* seqlock for synchronization */
__u32 index; /* hardware counter identifier */
__s64 offset; /* add to hardware counter value */
/*
* Control data for the mmap() data buffer.
*
* User-space reading this value should issue an rmb(), on SMP capable
* platforms, after reading this value -- see perf_counter_wakeup().
*/
__u32 data_head; /* head in the data section */
};
struct perf_event_header {
__u32 type;
__u32 size;
};
enum perf_event_type {
PERF_EVENT_MMAP = 1,
PERF_EVENT_MUNMAP = 2,
/*
* Half the event type space is reserved for the counter overflow
* bitfields, as found in hw_event.record_type.
*
* These events will have types of the form:
* PERF_EVENT_COUNTER_OVERFLOW { | __PERF_EVENT_* } *
*/
PERF_EVENT_COUNTER_OVERFLOW = 1UL << 31,
__PERF_EVENT_IP = PERF_RECORD_IP,
__PERF_EVENT_TID = PERF_RECORD_TID,
__PERF_EVENT_GROUP = PERF_RECORD_GROUP,
__PERF_EVENT_CALLCHAIN = PERF_RECORD_CALLCHAIN,
};
#ifdef __KERNEL__
/*
* Kernel-internal data types and definitions:
*/
#ifdef CONFIG_PERF_COUNTERS
# include <asm/perf_counter.h>
#endif
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/spinlock.h>
#include <linux/hrtimer.h>
#include <asm/atomic.h>
struct task_struct;
static inline u64 perf_event_raw(struct perf_counter_hw_event *hw_event)
{
return hw_event->config & PERF_COUNTER_RAW_MASK;
}
static inline u64 perf_event_config(struct perf_counter_hw_event *hw_event)
{
return hw_event->config & PERF_COUNTER_CONFIG_MASK;
}
static inline u64 perf_event_type(struct perf_counter_hw_event *hw_event)
{
return (hw_event->config & PERF_COUNTER_TYPE_MASK) >>
PERF_COUNTER_TYPE_SHIFT;
}
static inline u64 perf_event_id(struct perf_counter_hw_event *hw_event)
{
return hw_event->config & PERF_COUNTER_EVENT_MASK;
}
/**
* struct hw_perf_counter - performance counter hardware details:
*/
struct hw_perf_counter {
#ifdef CONFIG_PERF_COUNTERS
union {
struct { /* hardware */
u64 config;
unsigned long config_base;
unsigned long counter_base;
int nmi;
unsigned int idx;
};
union { /* software */
atomic64_t count;
struct hrtimer hrtimer;
};
};
atomic64_t prev_count;
u64 irq_period;
atomic64_t period_left;
#endif
};
struct perf_counter;
/**
* struct hw_perf_counter_ops - performance counter hw ops
*/
struct hw_perf_counter_ops {
int (*enable) (struct perf_counter *counter);
void (*disable) (struct perf_counter *counter);
void (*read) (struct perf_counter *counter);
};
/**
* enum perf_counter_active_state - the states of a counter
*/
enum perf_counter_active_state {
PERF_COUNTER_STATE_ERROR = -2,
PERF_COUNTER_STATE_OFF = -1,
PERF_COUNTER_STATE_INACTIVE = 0,
PERF_COUNTER_STATE_ACTIVE = 1,
};
struct file;
struct perf_mmap_data {
struct rcu_head rcu_head;
int nr_pages;
atomic_t wakeup;
atomic_t head;
atomic_t events;
struct perf_counter_mmap_page *user_page;
void *data_pages[0];
};
struct perf_wakeup_entry {
struct perf_wakeup_entry *next;
};
/**
* struct perf_counter - performance counter kernel representation:
*/
struct perf_counter {
#ifdef CONFIG_PERF_COUNTERS
struct list_head list_entry;
struct list_head event_entry;
struct list_head sibling_list;
int nr_siblings;
struct perf_counter *group_leader;
const struct hw_perf_counter_ops *hw_ops;
enum perf_counter_active_state state;
enum perf_counter_active_state prev_state;
atomic64_t count;
/*
* These are the total time in nanoseconds that the counter
* has been enabled (i.e. eligible to run, and the task has
* been scheduled in, if this is a per-task counter)
* and running (scheduled onto the CPU), respectively.
*
* They are computed from tstamp_enabled, tstamp_running and
* tstamp_stopped when the counter is in INACTIVE or ACTIVE state.
*/
u64 total_time_enabled;
u64 total_time_running;
/*
* These are timestamps used for computing total_time_enabled
* and total_time_running when the counter is in INACTIVE or
* ACTIVE state, measured in nanoseconds from an arbitrary point
* in time.
* tstamp_enabled: the notional time when the counter was enabled
* tstamp_running: the notional time when the counter was scheduled on
* tstamp_stopped: in INACTIVE state, the notional time when the
* counter was scheduled off.
*/
u64 tstamp_enabled;
u64 tstamp_running;
u64 tstamp_stopped;
struct perf_counter_hw_event hw_event;
struct hw_perf_counter hw;
struct perf_counter_context *ctx;
struct task_struct *task;
struct file *filp;
struct perf_counter *parent;
struct list_head child_list;
/*
* These accumulate total time (in nanoseconds) that children
* counters have been enabled and running, respectively.
*/
atomic64_t child_total_time_enabled;
atomic64_t child_total_time_running;
/*
* Protect attach/detach and child_list:
*/
struct mutex mutex;
int oncpu;
int cpu;
/* mmap bits */
struct mutex mmap_mutex;
atomic_t mmap_count;
struct perf_mmap_data *data;
/* poll related */
wait_queue_head_t waitq;
/* optional: for NMIs */
struct perf_wakeup_entry wakeup;
void (*destroy)(struct perf_counter *);
struct rcu_head rcu_head;
#endif
};
/**
* struct perf_counter_context - counter context structure
*
* Used as a container for task counters and CPU counters as well:
*/
struct perf_counter_context {
#ifdef CONFIG_PERF_COUNTERS
/*
* Protect the states of the counters in the list,
* nr_active, and the list:
*/
spinlock_t lock;
/*
* Protect the list of counters. Locking either mutex or lock
* is sufficient to ensure the list doesn't change; to change
* the list you need to lock both the mutex and the spinlock.
*/
struct mutex mutex;
struct list_head counter_list;
struct list_head event_list;
int nr_counters;
int nr_active;
int is_active;
struct task_struct *task;
/*
* time_now is the current time in nanoseconds since an arbitrary
* point in the past. For per-task counters, this is based on the
* task clock, and for per-cpu counters it is based on the cpu clock.
* time_lost is an offset from the task/cpu clock, used to make it
* appear that time only passes while the context is scheduled in.
*/
u64 time_now;
u64 time_lost;
#endif
};
/**
* struct perf_counter_cpu_context - per cpu counter context structure
*/
struct perf_cpu_context {
struct perf_counter_context ctx;
struct perf_counter_context *task_ctx;
int active_oncpu;
int max_pertask;
int exclusive;
/*
* Recursion avoidance:
*
* task, softirq, irq, nmi context
*/
int recursion[4];
};
/*
* Set by architecture code:
*/
extern int perf_max_counters;
#ifdef CONFIG_PERF_COUNTERS
extern const struct hw_perf_counter_ops *
hw_perf_counter_init(struct perf_counter *counter);
extern void perf_counter_task_sched_in(struct task_struct *task, int cpu);
extern void perf_counter_task_sched_out(struct task_struct *task, int cpu);
extern void perf_counter_task_tick(struct task_struct *task, int cpu);
extern void perf_counter_init_task(struct task_struct *child);
extern void perf_counter_exit_task(struct task_struct *child);
extern void perf_counter_do_pending(void);
extern void perf_counter_print_debug(void);
extern void perf_counter_unthrottle(void);
extern u64 hw_perf_save_disable(void);
extern void hw_perf_restore(u64 ctrl);
extern int perf_counter_task_disable(void);
extern int perf_counter_task_enable(void);
extern int hw_perf_group_sched_in(struct perf_counter *group_leader,
struct perf_cpu_context *cpuctx,
struct perf_counter_context *ctx, int cpu);
extern void perf_counter_update_userpage(struct perf_counter *counter);
extern void perf_counter_output(struct perf_counter *counter,
int nmi, struct pt_regs *regs);
/*
* Return 1 for a software counter, 0 for a hardware counter
*/
static inline int is_software_counter(struct perf_counter *counter)
{
return !perf_event_raw(&counter->hw_event) &&
perf_event_type(&counter->hw_event) != PERF_TYPE_HARDWARE;
}
extern void perf_swcounter_event(u32, u64, int, struct pt_regs *);
extern void perf_counter_mmap(unsigned long addr, unsigned long len,
unsigned long pgoff, struct file *file);
extern void perf_counter_munmap(unsigned long addr, unsigned long len,
unsigned long pgoff, struct file *file);
#define MAX_STACK_DEPTH 254
struct perf_callchain_entry {
u32 nr, hv, kernel, user;
u64 ip[MAX_STACK_DEPTH];
};
extern struct perf_callchain_entry *perf_callchain(struct pt_regs *regs);
#else
static inline void
perf_counter_task_sched_in(struct task_struct *task, int cpu) { }
static inline void
perf_counter_task_sched_out(struct task_struct *task, int cpu) { }
static inline void
perf_counter_task_tick(struct task_struct *task, int cpu) { }
static inline void perf_counter_init_task(struct task_struct *child) { }
static inline void perf_counter_exit_task(struct task_struct *child) { }
static inline void perf_counter_do_pending(void) { }
static inline void perf_counter_print_debug(void) { }
static inline void perf_counter_unthrottle(void) { }
static inline void hw_perf_restore(u64 ctrl) { }
static inline u64 hw_perf_save_disable(void) { return 0; }
static inline int perf_counter_task_disable(void) { return -EINVAL; }
static inline int perf_counter_task_enable(void) { return -EINVAL; }
static inline void
perf_swcounter_event(u32 event, u64 nr, int nmi, struct pt_regs *regs) { }
static inline void
perf_counter_mmap(unsigned long addr, unsigned long len,
unsigned long pgoff, struct file *file) { }
static inline void
perf_counter_munmap(unsigned long addr, unsigned long len,
unsigned long pgoff, struct file *file) { }
#endif
#endif /* __KERNEL__ */
#endif /* _LINUX_PERF_COUNTER_H */
