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/*
* Performance events:
*
* Copyright (C) 2008-2009, Thomas Gleixner <tglx@linutronix.de>
* Copyright (C) 2008-2011, Red Hat, Inc., Ingo Molnar
* Copyright (C) 2008-2011, Red Hat, Inc., Peter Zijlstra
*
* Data type definitions, declarations, prototypes.
*
* Started by: Thomas Gleixner and Ingo Molnar
*
* For licencing details see kernel-base/COPYING
*/
#ifndef _LINUX_PERF_EVENT_H
#define _LINUX_PERF_EVENT_H
#include <uapi/linux/perf_event.h>
#include <uapi/linux/bpf_perf_event.h>
/*
* Kernel-internal data types and definitions:
*/
#ifdef CONFIG_PERF_EVENTS
# include <asm/perf_event.h>
# include <asm/local64.h>
#endif
struct perf_guest_info_callbacks {
int (*is_in_guest)(void);
int (*is_user_mode)(void);
unsigned long (*get_guest_ip)(void);
void (*handle_intel_pt_intr)(void);
};
#ifdef CONFIG_HAVE_HW_BREAKPOINT
#include <asm/hw_breakpoint.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 <linux/fs.h>
#include <linux/pid_namespace.h>
#include <linux/workqueue.h>
#include <linux/ftrace.h>
#include <linux/cpu.h>
#include <linux/irq_work.h>
#include <linux/static_key.h>
#include <linux/jump_label_ratelimit.h>
#include <linux/atomic.h>
#include <linux/sysfs.h>
#include <linux/perf_regs.h>
#include <linux/cgroup.h>
#include <linux/refcount.h>
#include <linux/security.h>
#include <linux/static_call.h>
#include <asm/local.h>
struct perf_callchain_entry {
__u64 nr;
__u64 ip[]; /* /proc/sys/kernel/perf_event_max_stack */
};
struct perf_callchain_entry_ctx {
struct perf_callchain_entry *entry;
u32 max_stack;
u32 nr;
short contexts;
bool contexts_maxed;
};
typedef unsigned long (*perf_copy_f)(void *dst, const void *src,
unsigned long off, unsigned long len);
struct perf_raw_frag {
union {
struct perf_raw_frag *next;
unsigned long pad;
};
perf_copy_f copy;
void *data;
u32 size;
} __packed;
struct perf_raw_record {
struct perf_raw_frag frag;
u32 size;
};
/*
* branch stack layout:
* nr: number of taken branches stored in entries[]
* hw_idx: The low level index of raw branch records
* for the most recent branch.
* -1ULL means invalid/unknown.
*
* Note that nr can vary from sample to sample
* branches (to, from) are stored from most recent
* to least recent, i.e., entries[0] contains the most
* recent branch.
* The entries[] is an abstraction of raw branch records,
* which may not be stored in age order in HW, e.g. Intel LBR.
* The hw_idx is to expose the low level index of raw
* branch record for the most recent branch aka entries[0].
* The hw_idx index is between -1 (unknown) and max depth,
* which can be retrieved in /sys/devices/cpu/caps/branches.
* For the architectures whose raw branch records are
* already stored in age order, the hw_idx should be 0.
*/
struct perf_branch_stack {
__u64 nr;
__u64 hw_idx;
struct perf_branch_entry entries[];
};
struct task_struct;
/*
* extra PMU register associated with an event
*/
struct hw_perf_event_extra {
u64 config; /* register value */
unsigned int reg; /* register address or index */
int alloc; /* extra register already allocated */
int idx; /* index in shared_regs->regs[] */
};
/**
* struct hw_perf_event - performance event hardware details:
*/
struct hw_perf_event {
#ifdef CONFIG_PERF_EVENTS
union {
struct { /* hardware */
u64 config;
u64 last_tag;
unsigned long config_base;
unsigned long event_base;
int event_base_rdpmc;
int idx;
int last_cpu;
int flags;
struct hw_perf_event_extra extra_reg;
struct hw_perf_event_extra branch_reg;
};
struct { /* software */
struct hrtimer hrtimer;
};
struct { /* tracepoint */
/* for tp_event->class */
struct list_head tp_list;
};
struct { /* amd_power */
u64 pwr_acc;
u64 ptsc;
};
#ifdef CONFIG_HAVE_HW_BREAKPOINT
struct { /* breakpoint */
/*
* Crufty hack to avoid the chicken and egg
* problem hw_breakpoint has with context
* creation and event initalization.
*/
struct arch_hw_breakpoint info;
struct list_head bp_list;
};
#endif
struct { /* amd_iommu */
u8 iommu_bank;
u8 iommu_cntr;
u16 padding;
u64 conf;
u64 conf1;
};
};
/*
* If the event is a per task event, this will point to the task in
* question. See the comment in perf_event_alloc().
*/
struct task_struct *target;
/*
* PMU would store hardware filter configuration
* here.
*/
void *addr_filters;
/* Last sync'ed generation of filters */
unsigned long addr_filters_gen;
/*
* hw_perf_event::state flags; used to track the PERF_EF_* state.
*/
#define PERF_HES_STOPPED 0x01 /* the counter is stopped */
#define PERF_HES_UPTODATE 0x02 /* event->count up-to-date */
#define PERF_HES_ARCH 0x04
int state;
/*
* The last observed hardware counter value, updated with a
* local64_cmpxchg() such that pmu::read() can be called nested.
*/
local64_t prev_count;
/*
* The period to start the next sample with.
*/
u64 sample_period;
union {
struct { /* Sampling */
/*
* The period we started this sample with.
*/
u64 last_period;
/*
* However much is left of the current period;
* note that this is a full 64bit value and
* allows for generation of periods longer
* than hardware might allow.
*/
local64_t period_left;
};
struct { /* Topdown events counting for context switch */
u64 saved_metric;
u64 saved_slots;
};
};
/*
* State for throttling the event, see __perf_event_overflow() and
* perf_adjust_freq_unthr_context().
*/
u64 interrupts_seq;
u64 interrupts;
/*
* State for freq target events, see __perf_event_overflow() and
* perf_adjust_freq_unthr_context().
*/
u64 freq_time_stamp;
u64 freq_count_stamp;
#endif
};
struct perf_event;
/*
* Common implementation detail of pmu::{start,commit,cancel}_txn
*/
#define PERF_PMU_TXN_ADD 0x1 /* txn to add/schedule event on PMU */
#define PERF_PMU_TXN_READ 0x2 /* txn to read event group from PMU */
/**
* pmu::capabilities flags
*/
#define PERF_PMU_CAP_NO_INTERRUPT 0x0001
#define PERF_PMU_CAP_NO_NMI 0x0002
#define PERF_PMU_CAP_AUX_NO_SG 0x0004
#define PERF_PMU_CAP_EXTENDED_REGS 0x0008
#define PERF_PMU_CAP_EXCLUSIVE 0x0010
#define PERF_PMU_CAP_ITRACE 0x0020
#define PERF_PMU_CAP_HETEROGENEOUS_CPUS 0x0040
#define PERF_PMU_CAP_NO_EXCLUDE 0x0080
#define PERF_PMU_CAP_AUX_OUTPUT 0x0100
#define PERF_PMU_CAP_EXTENDED_HW_TYPE 0x0200
struct perf_output_handle;
/**
* struct pmu - generic performance monitoring unit
*/
struct pmu {
struct list_head entry;
struct module *module;
struct device *dev;
const struct attribute_group **attr_groups;
const struct attribute_group **attr_update;
const char *name;
int type;
/*
* various common per-pmu feature flags
*/
int capabilities;
int __percpu *pmu_disable_count;
struct perf_cpu_context __percpu *pmu_cpu_context;
atomic_t exclusive_cnt; /* < 0: cpu; > 0: tsk */
int task_ctx_nr;
int hrtimer_interval_ms;
/* number of address filters this PMU can do */
unsigned int nr_addr_filters;
/*
* Fully disable/enable this PMU, can be used to protect from the PMI
* as well as for lazy/batch writing of the MSRs.
*/
void (*pmu_enable) (struct pmu *pmu); /* optional */
void (*pmu_disable) (struct pmu *pmu); /* optional */
/*
* Try and initialize the event for this PMU.
*
* Returns:
* -ENOENT -- @event is not for this PMU
*
* -ENODEV -- @event is for this PMU but PMU not present
* -EBUSY -- @event is for this PMU but PMU temporarily unavailable
* -EINVAL -- @event is for this PMU but @event is not valid
* -EOPNOTSUPP -- @event is for this PMU, @event is valid, but not supported
* -EACCES -- @event is for this PMU, @event is valid, but no privileges
*
* 0 -- @event is for this PMU and valid
*
* Other error return values are allowed.
*/
int (*event_init) (struct perf_event *event);
/*
* Notification that the event was mapped or unmapped. Called
* in the context of the mapping task.
*/
void (*event_mapped) (struct perf_event *event, struct mm_struct *mm); /* optional */
void (*event_unmapped) (struct perf_event *event, struct mm_struct *mm); /* optional */
/*
* Flags for ->add()/->del()/ ->start()/->stop(). There are
* matching hw_perf_event::state flags.
*/
#define PERF_EF_START 0x01 /* start the counter when adding */
#define PERF_EF_RELOAD 0x02 /* reload the counter when starting */
#define PERF_EF_UPDATE 0x04 /* update the counter when stopping */
/*
* Adds/Removes a counter to/from the PMU, can be done inside a
* transaction, see the ->*_txn() methods.
*
* The add/del callbacks will reserve all hardware resources required
* to service the event, this includes any counter constraint
* scheduling etc.
*
* Called with IRQs disabled and the PMU disabled on the CPU the event
* is on.
*
* ->add() called without PERF_EF_START should result in the same state
* as ->add() followed by ->stop().
*
* ->del() must always PERF_EF_UPDATE stop an event. If it calls
* ->stop() that must deal with already being stopped without
* PERF_EF_UPDATE.
*/
int (*add) (struct perf_event *event, int flags);
void (*del) (struct perf_event *event, int flags);
/*
* Starts/Stops a counter present on the PMU.
*
* The PMI handler should stop the counter when perf_event_overflow()
* returns !0. ->start() will be used to continue.
*
* Also used to change the sample period.
*
* Called with IRQs disabled and the PMU disabled on the CPU the event
* is on -- will be called from NMI context with the PMU generates
* NMIs.
*
* ->stop() with PERF_EF_UPDATE will read the counter and update
* period/count values like ->read() would.
*
* ->start() with PERF_EF_RELOAD will reprogram the counter
* value, must be preceded by a ->stop() with PERF_EF_UPDATE.
*/
void (*start) (struct perf_event *event, int flags);
void (*stop) (struct perf_event *event, int flags);
/*
* Updates the counter value of the event.
*
* For sampling capable PMUs this will also update the software period
* hw_perf_event::period_left field.
*/
void (*read) (struct perf_event *event);
/*
* Group events scheduling is treated as a transaction, add
* group events as a whole and perform one schedulability test.
* If the test fails, roll back the whole group
*
* Start the transaction, after this ->add() doesn't need to
* do schedulability tests.
*
* Optional.
*/
void (*start_txn) (struct pmu *pmu, unsigned int txn_flags);
/*
* If ->start_txn() disabled the ->add() schedulability test
* then ->commit_txn() is required to perform one. On success
* the transaction is closed. On error the transaction is kept
* open until ->cancel_txn() is called.
*
* Optional.
*/
int (*commit_txn) (struct pmu *pmu);
/*
* Will cancel the transaction, assumes ->del() is called
* for each successful ->add() during the transaction.
*
* Optional.
*/
void (*cancel_txn) (struct pmu *pmu);
/*
* Will return the value for perf_event_mmap_page::index for this event,
* if no implementation is provided it will default to: event->hw.idx + 1.
*/
int (*event_idx) (struct perf_event *event); /*optional */
/*
* context-switches callback
*/
void (*sched_task) (struct perf_event_context *ctx,
bool sched_in);
/*
* Kmem cache of PMU specific data
*/
struct kmem_cache *task_ctx_cache;
/*
* PMU specific parts of task perf event context (i.e. ctx->task_ctx_data)
* can be synchronized using this function. See Intel LBR callstack support
* implementation and Perf core context switch handling callbacks for usage
* examples.
*/
void (*swap_task_ctx) (struct perf_event_context *prev,
struct perf_event_context *next);
/* optional */
/*
* Set up pmu-private data structures for an AUX area
*/
void *(*setup_aux) (struct perf_event *event, void **pages,
int nr_pages, bool overwrite);
/* optional */
/*
* Free pmu-private AUX data structures
*/
void (*free_aux) (void *aux); /* optional */
/*
* Take a snapshot of the AUX buffer without touching the event
* state, so that preempting ->start()/->stop() callbacks does
* not interfere with their logic. Called in PMI context.
*
* Returns the size of AUX data copied to the output handle.
*
* Optional.
*/
long (*snapshot_aux) (struct perf_event *event,
struct perf_output_handle *handle,
unsigned long size);
/*
* Validate address range filters: make sure the HW supports the
* requested configuration and number of filters; return 0 if the
* supplied filters are valid, -errno otherwise.
*
* Runs in the context of the ioctl()ing process and is not serialized
* with the rest of the PMU callbacks.
*/
int (*addr_filters_validate) (struct list_head *filters);
/* optional */
/*
* Synchronize address range filter configuration:
* translate hw-agnostic filters into hardware configuration in
* event::hw::addr_filters.
*
* Runs as a part of filter sync sequence that is done in ->start()
* callback by calling perf_event_addr_filters_sync().
*
* May (and should) traverse event::addr_filters::list, for which its
* caller provides necessary serialization.
*/
void (*addr_filters_sync) (struct perf_event *event);
/* optional */
/*
* Check if event can be used for aux_output purposes for
* events of this PMU.
*
* Runs from perf_event_open(). Should return 0 for "no match"
* or non-zero for "match".
*/
int (*aux_output_match) (struct perf_event *event);
/* optional */
/*
* Filter events for PMU-specific reasons.
*/
int (*filter_match) (struct perf_event *event); /* optional */
/*
* Check period value for PERF_EVENT_IOC_PERIOD ioctl.
*/
int (*check_period) (struct perf_event *event, u64 value); /* optional */
};
enum perf_addr_filter_action_t {
PERF_ADDR_FILTER_ACTION_STOP = 0,
PERF_ADDR_FILTER_ACTION_START,
PERF_ADDR_FILTER_ACTION_FILTER,
};
/**
* struct perf_addr_filter - address range filter definition
* @entry: event's filter list linkage
* @path: object file's path for file-based filters
* @offset: filter range offset
* @size: filter range size (size==0 means single address trigger)
* @action: filter/start/stop
*
* This is a hardware-agnostic filter configuration as specified by the user.
*/
struct perf_addr_filter {
struct list_head entry;
struct path path;
unsigned long offset;
unsigned long size;
enum perf_addr_filter_action_t action;
};
/**
* struct perf_addr_filters_head - container for address range filters
* @list: list of filters for this event
* @lock: spinlock that serializes accesses to the @list and event's
* (and its children's) filter generations.
* @nr_file_filters: number of file-based filters
*
* A child event will use parent's @list (and therefore @lock), so they are
* bundled together; see perf_event_addr_filters().
*/
struct perf_addr_filters_head {
struct list_head list;
raw_spinlock_t lock;
unsigned int nr_file_filters;
};
struct perf_addr_filter_range {
unsigned long start;
unsigned long size;
};
/**
* enum perf_event_state - the states of an event:
*/
enum perf_event_state {
PERF_EVENT_STATE_DEAD = -4,
PERF_EVENT_STATE_EXIT = -3,
PERF_EVENT_STATE_ERROR = -2,
PERF_EVENT_STATE_OFF = -1,
PERF_EVENT_STATE_INACTIVE = 0,
PERF_EVENT_STATE_ACTIVE = 1,
};
struct file;
struct perf_sample_data;
typedef void (*perf_overflow_handler_t)(struct perf_event *,
struct perf_sample_data *,
struct pt_regs *regs);
/*
* Event capabilities. For event_caps and groups caps.
*
* PERF_EV_CAP_SOFTWARE: Is a software event.
* PERF_EV_CAP_READ_ACTIVE_PKG: A CPU event (or cgroup event) that can be read
* from any CPU in the package where it is active.
* PERF_EV_CAP_SIBLING: An event with this flag must be a group sibling and
* cannot be a group leader. If an event with this flag is detached from the
* group it is scheduled out and moved into an unrecoverable ERROR state.
*/
#define PERF_EV_CAP_SOFTWARE BIT(0)
#define PERF_EV_CAP_READ_ACTIVE_PKG BIT(1)
#define PERF_EV_CAP_SIBLING BIT(2)
#define SWEVENT_HLIST_BITS 8
#define SWEVENT_HLIST_SIZE (1 << SWEVENT_HLIST_BITS)
struct swevent_hlist {
struct hlist_head heads[SWEVENT_HLIST_SIZE];
struct rcu_head rcu_head;
};
#define PERF_ATTACH_CONTEXT 0x01
#define PERF_ATTACH_GROUP 0x02
#define PERF_ATTACH_TASK 0x04
#define PERF_ATTACH_TASK_DATA 0x08
#define PERF_ATTACH_ITRACE 0x10
#define PERF_ATTACH_SCHED_CB 0x20
#define PERF_ATTACH_CHILD 0x40
struct perf_cgroup;
struct perf_buffer;
struct pmu_event_list {
raw_spinlock_t lock;
struct list_head list;
};
#define for_each_sibling_event(sibling, event) \
if ((event)->group_leader == (event)) \
list_for_each_entry((sibling), &(event)->sibling_list, sibling_list)
/**
* struct perf_event - performance event kernel representation:
*/
struct perf_event {
#ifdef CONFIG_PERF_EVENTS
/*
* entry onto perf_event_context::event_list;
* modifications require ctx->lock
* RCU safe iterations.
*/
struct list_head event_entry;
/*
* Locked for modification by both ctx->mutex and ctx->lock; holding
* either sufficies for read.
*/
struct list_head sibling_list;
struct list_head active_list;
/*
* Node on the pinned or flexible tree located at the event context;
*/
struct rb_node group_node;
u64 group_index;
/*
* We need storage to track the entries in perf_pmu_migrate_context; we
* cannot use the event_entry because of RCU and we want to keep the
* group in tact which avoids us using the other two entries.
*/
struct list_head migrate_entry;
struct hlist_node hlist_entry;
struct list_head active_entry;
int nr_siblings;
/* Not serialized. Only written during event initialization. */
int event_caps;
/* The cumulative AND of all event_caps for events in this group. */
int group_caps;
struct perf_event *group_leader;
struct pmu *pmu;
void *pmu_private;
enum perf_event_state state;
unsigned int attach_state;
local64_t count;
atomic64_t child_count;
/*
* These are the total time in nanoseconds that the event
* has been enabled (i.e. eligible to run, and the task has
* been scheduled in, if this is a per-task event)
* and running (scheduled onto the CPU), respectively.
*/
u64 total_time_enabled;
u64 total_time_running;
u64 tstamp;
/*
* timestamp shadows the actual context timing but it can
* be safely used in NMI interrupt context. It reflects the
* context time as it was when the event was last scheduled in,
* or when ctx_sched_in failed to schedule the event because we
* run out of PMC.
*
* ctx_time already accounts for ctx->timestamp. Therefore to
* compute ctx_time for a sample, simply add perf_clock().
*/
u64 shadow_ctx_time;
struct perf_event_attr attr;
u16 header_size;
u16 id_header_size;
u16 read_size;
struct hw_perf_event hw;
struct perf_event_context *ctx;
atomic_long_t refcount;
/*
* These accumulate total time (in nanoseconds) that children
* events 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 child_mutex;
struct list_head child_list;
struct perf_event *parent;
int oncpu;
int cpu;
struct list_head owner_entry;
struct task_struct *owner;
/* mmap bits */
struct mutex mmap_mutex;
atomic_t mmap_count;
struct perf_buffer *rb;
struct list_head rb_entry;
unsigned long rcu_batches;
int rcu_pending;
/* poll related */
wait_queue_head_t waitq;
struct fasync_struct *fasync;
/* delayed work for NMIs and such */
int pending_wakeup;
int pending_kill;
int pending_disable;
unsigned long pending_addr; /* SIGTRAP */
struct irq_work pending;
atomic_t event_limit;
/* address range filters */
struct perf_addr_filters_head addr_filters;
/* vma address array for file-based filders */
struct perf_addr_filter_range *addr_filter_ranges;
unsigned long addr_filters_gen;
/* for aux_output events */
struct perf_event *aux_event;
void (*destroy)(struct perf_event *);
struct rcu_head rcu_head;
struct pid_namespace *ns;
u64 id;
u64 (*clock)(void);
perf_overflow_handler_t overflow_handler;
void *overflow_handler_context;
#ifdef CONFIG_BPF_SYSCALL
perf_overflow_handler_t orig_overflow_handler;
struct bpf_prog *prog;
u64 bpf_cookie;
#endif
#ifdef CONFIG_EVENT_TRACING
struct trace_event_call *tp_event;
struct event_filter *filter;
#ifdef CONFIG_FUNCTION_TRACER
struct ftrace_ops ftrace_ops;
#endif
#endif
#ifdef CONFIG_CGROUP_PERF
struct perf_cgroup *cgrp; /* cgroup event is attach to */
#endif
#ifdef CONFIG_SECURITY
void *security;
#endif
struct list_head sb_list;
#endif /* CONFIG_PERF_EVENTS */
};
struct perf_event_groups {
struct rb_root tree;
u64 index;
};
/**
* struct perf_event_context - event context structure
*
* Used as a container for task events and CPU events as well:
*/
struct perf_event_context {
struct pmu *pmu;
/*
* Protect the states of the events in the list,
* nr_active, and the list:
*/
raw_spinlock_t lock;
/*
* Protect the list of events. 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 active_ctx_list;
struct perf_event_groups pinned_groups;
struct perf_event_groups flexible_groups;
struct list_head event_list;
struct list_head pinned_active;
struct list_head flexible_active;
int nr_events;
int nr_active;
int is_active;
int nr_stat;
int nr_freq;
int rotate_disable;
/*
* Set when nr_events != nr_active, except tolerant to events not
* necessary to be active due to scheduling constraints, such as cgroups.
*/
int rotate_necessary;
refcount_t refcount;
struct task_struct *task;
/*
* Context clock, runs when context enabled.
*/
u64 time;
u64 timestamp;
/*
* These fields let us detect when two contexts have both
* been cloned (inherited) from a common ancestor.
*/
struct perf_event_context *parent_ctx;
u64 parent_gen;
u64 generation;
int pin_count;
#ifdef CONFIG_CGROUP_PERF
int nr_cgroups; /* cgroup evts */
#endif
void *task_ctx_data; /* pmu specific data */
struct rcu_head rcu_head;
};
/*
* Number of contexts where an event can trigger:
* task, softirq, hardirq, nmi.
*/
#define PERF_NR_CONTEXTS 4
/**
* struct perf_event_cpu_context - per cpu event context structure
*/
struct perf_cpu_context {
struct perf_event_context ctx;
struct perf_event_context *task_ctx;
int active_oncpu;
int exclusive;
raw_spinlock_t hrtimer_lock;
struct hrtimer hrtimer;
ktime_t hrtimer_interval;
unsigned int hrtimer_active;
#ifdef CONFIG_CGROUP_PERF
struct perf_cgroup *cgrp;
struct list_head cgrp_cpuctx_entry;
#endif
struct list_head sched_cb_entry;
int sched_cb_usage;
int online;
/*
* Per-CPU storage for iterators used in visit_groups_merge. The default
* storage is of size 2 to hold the CPU and any CPU event iterators.
*/
int heap_size;
struct perf_event **heap;
struct perf_event *heap_default[2];
};
struct perf_output_handle {
struct perf_event *event;
struct perf_buffer *rb;
unsigned long wakeup;
unsigned long size;
u64 aux_flags;
union {
void *addr;
unsigned long head;
};
int page;
};
struct bpf_perf_event_data_kern {
bpf_user_pt_regs_t *regs;
struct perf_sample_data *data;
struct perf_event *event;
};
#ifdef CONFIG_CGROUP_PERF
/*
* perf_cgroup_info keeps track of time_enabled for a cgroup.
* This is a per-cpu dynamically allocated data structure.
*/
struct perf_cgroup_info {
u64 time;
u64 timestamp;
};
struct perf_cgroup {
struct cgroup_subsys_state css;
struct perf_cgroup_info __percpu *info;
};
/*
* Must ensure cgroup is pinned (css_get) before calling
* this function. In other words, we cannot call this function
* if there is no cgroup event for the current CPU context.
*/
static inline struct perf_cgroup *
perf_cgroup_from_task(struct task_struct *task, struct perf_event_context *ctx)
{
return container_of(task_css_check(task, perf_event_cgrp_id,
ctx ? lockdep_is_held(&ctx->lock)
: true),
struct perf_cgroup, css);
}
#endif /* CONFIG_CGROUP_PERF */
#ifdef CONFIG_PERF_EVENTS
extern void *perf_aux_output_begin(struct perf_output_handle *handle,
struct perf_event *event);
extern void perf_aux_output_end(struct perf_output_handle *handle,
unsigned long size);
extern int perf_aux_output_skip(struct perf_output_handle *handle,
unsigned long size);
extern void *perf_get_aux(struct perf_output_handle *handle);
extern void perf_aux_output_flag(struct perf_output_handle *handle, u64 flags);
extern void perf_event_itrace_started(struct perf_event *event);
extern int perf_pmu_register(struct pmu *pmu, const char *name, int type);
extern void perf_pmu_unregister(struct pmu *pmu);
extern void __perf_event_task_sched_in(struct task_struct *prev,
struct task_struct *task);
extern void __perf_event_task_sched_out(struct task_struct *prev,
struct task_struct *next);
extern int perf_event_init_task(struct task_struct *child, u64 clone_flags);
extern void perf_event_exit_task(struct task_struct *child);
extern void perf_event_free_task(struct task_struct *task);
extern void perf_event_delayed_put(struct task_struct *task);
extern struct file *perf_event_get(unsigned int fd);
extern const struct perf_event *perf_get_event(struct file *file);
extern const struct perf_event_attr *perf_event_attrs(struct perf_event *event);
extern void perf_event_print_debug(void);
extern void perf_pmu_disable(struct pmu *pmu);
extern void perf_pmu_enable(struct pmu *pmu);
extern void perf_sched_cb_dec(struct pmu *pmu);
extern void perf_sched_cb_inc(struct pmu *pmu);
extern int perf_event_task_disable(void);
extern int perf_event_task_enable(void);
extern void perf_pmu_resched(struct pmu *pmu);
extern int perf_event_refresh(struct perf_event *event, int refresh);
extern void perf_event_update_userpage(struct perf_event *event);
extern int perf_event_release_kernel(struct perf_event *event);
extern struct perf_event *
perf_event_create_kernel_counter(struct perf_event_attr *attr,
int cpu,
struct task_struct *task,
perf_overflow_handler_t callback,
void *context);
extern void perf_pmu_migrate_context(struct pmu *pmu,
int src_cpu, int dst_cpu);
int perf_event_read_local(struct perf_event *event, u64 *value,
u64 *enabled, u64 *running);
extern u64 perf_event_read_value(struct perf_event *event,
u64 *enabled, u64 *running);
struct perf_sample_data {
/*
* Fields set by perf_sample_data_init(), group so as to
* minimize the cachelines touched.
*/
u64 addr;
struct perf_raw_record *raw;
struct perf_branch_stack *br_stack;
u64 period;
union perf_sample_weight weight;
u64 txn;
union perf_mem_data_src data_src;
/*
* The other fields, optionally {set,used} by
* perf_{prepare,output}_sample().
*/
u64 type;
u64 ip;
struct {
u32 pid;
u32 tid;
} tid_entry;
u64 time;
u64 id;
u64 stream_id;
struct {
u32 cpu;
u32 reserved;
} cpu_entry;
struct perf_callchain_entry *callchain;
u64 aux_size;
struct perf_regs regs_user;
struct perf_regs regs_intr;
u64 stack_user_size;
u64 phys_addr;
u64 cgroup;
u64 data_page_size;
u64 code_page_size;
} ____cacheline_aligned;
/* default value for data source */
#define PERF_MEM_NA (PERF_MEM_S(OP, NA) |\
PERF_MEM_S(LVL, NA) |\
PERF_MEM_S(SNOOP, NA) |\
PERF_MEM_S(LOCK, NA) |\
PERF_MEM_S(TLB, NA))
static inline void perf_sample_data_init(struct perf_sample_data *data,
u64 addr, u64 period)
{
/* remaining struct members initialized in perf_prepare_sample() */
data->addr = addr;
data->raw = NULL;
data->br_stack = NULL;
data->period = period;
data->weight.full = 0;
data->data_src.val = PERF_MEM_NA;
data->txn = 0;
}
extern void perf_output_sample(struct perf_output_handle *handle,
struct perf_event_header *header,
struct perf_sample_data *data,
struct perf_event *event);
extern void perf_prepare_sample(struct perf_event_header *header,
struct perf_sample_data *data,
struct perf_event *event,
struct pt_regs *regs);
extern int perf_event_overflow(struct perf_event *event,
struct perf_sample_data *data,
struct pt_regs *regs);
extern void perf_event_output_forward(struct perf_event *event,
struct perf_sample_data *data,
struct pt_regs *regs);
extern void perf_event_output_backward(struct perf_event *event,
struct perf_sample_data *data,
struct pt_regs *regs);
extern int perf_event_output(struct perf_event *event,
struct perf_sample_data *data,
struct pt_regs *regs);
static inline bool
is_default_overflow_handler(struct perf_event *event)
{
if (likely(event->overflow_handler == perf_event_output_forward))
return true;
if (unlikely(event->overflow_handler == perf_event_output_backward))
return true;
return false;
}
extern void
perf_event_header__init_id(struct perf_event_header *header,
struct perf_sample_data *data,
struct perf_event *event);
extern void
perf_event__output_id_sample(struct perf_event *event,
struct perf_output_handle *handle,
struct perf_sample_data *sample);
extern void
perf_log_lost_samples(struct perf_event *event, u64 lost);
static inline bool event_has_any_exclude_flag(struct perf_event *event)
{
struct perf_event_attr *attr = &event->attr;
return attr->exclude_idle || attr->exclude_user ||
attr->exclude_kernel || attr->exclude_hv ||
attr->exclude_guest || attr->exclude_host;
}
static inline bool is_sampling_event(struct perf_event *event)
{
return event->attr.sample_period != 0;
}
/*
* Return 1 for a software event, 0 for a hardware event
*/
static inline int is_software_event(struct perf_event *event)
{
return event->event_caps & PERF_EV_CAP_SOFTWARE;
}
/*
* Return 1 for event in sw context, 0 for event in hw context
*/
static inline int in_software_context(struct perf_event *event)
{
return event->ctx->pmu->task_ctx_nr == perf_sw_context;
}
static inline int is_exclusive_pmu(struct pmu *pmu)
{
return pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE;
}
extern struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX];
extern void ___perf_sw_event(u32, u64, struct pt_regs *, u64);
extern void __perf_sw_event(u32, u64, struct pt_regs *, u64);
#ifndef perf_arch_fetch_caller_regs
static inline void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip) { }
#endif
/*
* When generating a perf sample in-line, instead of from an interrupt /
* exception, we lack a pt_regs. This is typically used from software events
* like: SW_CONTEXT_SWITCHES, SW_MIGRATIONS and the tie-in with tracepoints.
*
* We typically don't need a full set, but (for x86) do require:
* - ip for PERF_SAMPLE_IP
* - cs for user_mode() tests
* - sp for PERF_SAMPLE_CALLCHAIN
* - eflags for MISC bits and CALLCHAIN (see: perf_hw_regs())
*
* NOTE: assumes @regs is otherwise already 0 filled; this is important for
* things like PERF_SAMPLE_REGS_INTR.
*/
static inline void perf_fetch_caller_regs(struct pt_regs *regs)
{
perf_arch_fetch_caller_regs(regs, CALLER_ADDR0);
}
static __always_inline void
perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr)
{
if (static_key_false(&perf_swevent_enabled[event_id]))
__perf_sw_event(event_id, nr, regs, addr);
}
DECLARE_PER_CPU(struct pt_regs, __perf_regs[4]);
/*
* 'Special' version for the scheduler, it hard assumes no recursion,
* which is guaranteed by us not actually scheduling inside other swevents
* because those disable preemption.
*/
static __always_inline void __perf_sw_event_sched(u32 event_id, u64 nr, u64 addr)
{
struct pt_regs *regs = this_cpu_ptr(&__perf_regs[0]);
perf_fetch_caller_regs(regs);
___perf_sw_event(event_id, nr, regs, addr);
}
extern struct static_key_false perf_sched_events;
static __always_inline bool __perf_sw_enabled(int swevt)
{
return static_key_false(&perf_swevent_enabled[swevt]);
}
static inline void perf_event_task_migrate(struct task_struct *task)
{
if (__perf_sw_enabled(PERF_COUNT_SW_CPU_MIGRATIONS))
task->sched_migrated = 1;
}
static inline void perf_event_task_sched_in(struct task_struct *prev,
struct task_struct *task)
{
if (static_branch_unlikely(&perf_sched_events))
__perf_event_task_sched_in(prev, task);
if (__perf_sw_enabled(PERF_COUNT_SW_CPU_MIGRATIONS) &&
task->sched_migrated) {
__perf_sw_event_sched(PERF_COUNT_SW_CPU_MIGRATIONS, 1, 0);
task->sched_migrated = 0;
}
}
static inline void perf_event_task_sched_out(struct task_struct *prev,
struct task_struct *next)
{
if (__perf_sw_enabled(PERF_COUNT_SW_CONTEXT_SWITCHES))
__perf_sw_event_sched(PERF_COUNT_SW_CONTEXT_SWITCHES, 1, 0);
#ifdef CONFIG_CGROUP_PERF
if (__perf_sw_enabled(PERF_COUNT_SW_CGROUP_SWITCHES) &&
perf_cgroup_from_task(prev, NULL) !=
perf_cgroup_from_task(next, NULL))
__perf_sw_event_sched(PERF_COUNT_SW_CGROUP_SWITCHES, 1, 0);
#endif
if (static_branch_unlikely(&perf_sched_events))
__perf_event_task_sched_out(prev, next);
}
extern void perf_event_mmap(struct vm_area_struct *vma);
extern void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len,
bool unregister, const char *sym);
extern void perf_event_bpf_event(struct bpf_prog *prog,
enum perf_bpf_event_type type,
u16 flags);
extern struct perf_guest_info_callbacks *perf_guest_cbs;
extern int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
extern int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *callbacks);
extern void perf_event_exec(void);
extern void perf_event_comm(struct task_struct *tsk, bool exec);
extern void perf_event_namespaces(struct task_struct *tsk);
extern void perf_event_fork(struct task_struct *tsk);
extern void perf_event_text_poke(const void *addr,
const void *old_bytes, size_t old_len,
const void *new_bytes, size_t new_len);
/* Callchains */
DECLARE_PER_CPU(struct perf_callchain_entry, perf_callchain_entry);
extern void perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
extern void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs);
extern struct perf_callchain_entry *
get_perf_callchain(struct pt_regs *regs, u32 init_nr, bool kernel, bool user,
u32 max_stack, bool crosstask, bool add_mark);
extern struct perf_callchain_entry *perf_callchain(struct perf_event *event, struct pt_regs *regs);
extern int get_callchain_buffers(int max_stack);
extern void put_callchain_buffers(void);
extern struct perf_callchain_entry *get_callchain_entry(int *rctx);
extern void put_callchain_entry(int rctx);
extern int sysctl_perf_event_max_stack;
extern int sysctl_perf_event_max_contexts_per_stack;
static inline int perf_callchain_store_context(struct perf_callchain_entry_ctx *ctx, u64 ip)
{
if (ctx->contexts < sysctl_perf_event_max_contexts_per_stack) {
struct perf_callchain_entry *entry = ctx->entry;
entry->ip[entry->nr++] = ip;
++ctx->contexts;
return 0;
} else {
ctx->contexts_maxed = true;
return -1; /* no more room, stop walking the stack */
}
}
static inline int perf_callchain_store(struct perf_callchain_entry_ctx *ctx, u64 ip)
{
if (ctx->nr < ctx->max_stack && !ctx->contexts_maxed) {
struct perf_callchain_entry *entry = ctx->entry;
entry->ip[entry->nr++] = ip;
++ctx->nr;
return 0;
} else {
return -1; /* no more room, stop walking the stack */
}
}
extern int sysctl_perf_event_paranoid;
extern int sysctl_perf_event_mlock;
extern int sysctl_perf_event_sample_rate;
extern int sysctl_perf_cpu_time_max_percent;
extern void perf_sample_event_took(u64 sample_len_ns);
int perf_proc_update_handler(struct ctl_table *table, int write,
void *buffer, size_t *lenp, loff_t *ppos);
int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
void *buffer, size_t *lenp, loff_t *ppos);
int perf_event_max_stack_handler(struct ctl_table *table, int write,
void *buffer, size_t *lenp, loff_t *ppos);
/* Access to perf_event_open(2) syscall. */
#define PERF_SECURITY_OPEN 0
/* Finer grained perf_event_open(2) access control. */
#define PERF_SECURITY_CPU 1
#define PERF_SECURITY_KERNEL 2
#define PERF_SECURITY_TRACEPOINT 3
static inline int perf_is_paranoid(void)
{
return sysctl_perf_event_paranoid > -1;
}
static inline int perf_allow_kernel(struct perf_event_attr *attr)
{
if (sysctl_perf_event_paranoid > 1 && !perfmon_capable())
return -EACCES;
return security_perf_event_open(attr, PERF_SECURITY_KERNEL);
}
static inline int perf_allow_cpu(struct perf_event_attr *attr)
{
if (sysctl_perf_event_paranoid > 0 && !perfmon_capable())
return -EACCES;
return security_perf_event_open(attr, PERF_SECURITY_CPU);
}
static inline int perf_allow_tracepoint(struct perf_event_attr *attr)
{
if (sysctl_perf_event_paranoid > -1 && !perfmon_capable())
return -EPERM;
return security_perf_event_open(attr, PERF_SECURITY_TRACEPOINT);
}
extern void perf_event_init(void);
extern void perf_tp_event(u16 event_type, u64 count, void *record,
int entry_size, struct pt_regs *regs,
struct hlist_head *head, int rctx,
struct task_struct *task);
extern void perf_bp_event(struct perf_event *event, void *data);
#ifndef perf_misc_flags
# define perf_misc_flags(regs) \
(user_mode(regs) ? PERF_RECORD_MISC_USER : PERF_RECORD_MISC_KERNEL)
# define perf_instruction_pointer(regs) instruction_pointer(regs)
#endif
#ifndef perf_arch_bpf_user_pt_regs
# define perf_arch_bpf_user_pt_regs(regs) regs
#endif
static inline bool has_branch_stack(struct perf_event *event)
{
return event->attr.sample_type & PERF_SAMPLE_BRANCH_STACK;
}
static inline bool needs_branch_stack(struct perf_event *event)
{
return event->attr.branch_sample_type != 0;
}
static inline bool has_aux(struct perf_event *event)
{
return event->pmu->setup_aux;
}
static inline bool is_write_backward(struct perf_event *event)
{
return !!event->attr.write_backward;
}
static inline bool has_addr_filter(struct perf_event *event)
{
return event->pmu->nr_addr_filters;
}
/*
* An inherited event uses parent's filters
*/
static inline struct perf_addr_filters_head *
perf_event_addr_filters(struct perf_event *event)
{
struct perf_addr_filters_head *ifh = &event->addr_filters;
if (event->parent)
ifh = &event->parent->addr_filters;
return ifh;
}
extern void perf_event_addr_filters_sync(struct perf_event *event);
extern void perf_report_aux_output_id(struct perf_event *event, u64 hw_id);
extern int perf_output_begin(struct perf_output_handle *handle,
struct perf_sample_data *data,
struct perf_event *event, unsigned int size);
extern int perf_output_begin_forward(struct perf_output_handle *handle,
struct perf_sample_data *data,
struct perf_event *event,
unsigned int size);
extern int perf_output_begin_backward(struct perf_output_handle *handle,
struct perf_sample_data *data,
struct perf_event *event,
unsigned int size);
extern void perf_output_end(struct perf_output_handle *handle);
extern unsigned int perf_output_copy(struct perf_output_handle *handle,
const void *buf, unsigned int len);
extern unsigned int perf_output_skip(struct perf_output_handle *handle,
unsigned int len);
extern long perf_output_copy_aux(struct perf_output_handle *aux_handle,
struct perf_output_handle *handle,
unsigned long from, unsigned long to);
extern int perf_swevent_get_recursion_context(void);
extern void perf_swevent_put_recursion_context(int rctx);
extern u64 perf_swevent_set_period(struct perf_event *event);
extern void perf_event_enable(struct perf_event *event);
extern void perf_event_disable(struct perf_event *event);
extern void perf_event_disable_local(struct perf_event *event);
extern void perf_event_disable_inatomic(struct perf_event *event);
extern void perf_event_task_tick(void);
extern int perf_event_account_interrupt(struct perf_event *event);
extern int perf_event_period(struct perf_event *event, u64 value);
extern u64 perf_event_pause(struct perf_event *event, bool reset);
#else /* !CONFIG_PERF_EVENTS: */
static inline void *
perf_aux_output_begin(struct perf_output_handle *handle,
struct perf_event *event) { return NULL; }
static inline void
perf_aux_output_end(struct perf_output_handle *handle, unsigned long size)
{ }
static inline int
perf_aux_output_skip(struct perf_output_handle *handle,
unsigned long size) { return -EINVAL; }
static inline void *
perf_get_aux(struct perf_output_handle *handle) { return NULL; }
static inline void
perf_event_task_migrate(struct task_struct *task) { }
static inline void
perf_event_task_sched_in(struct task_struct *prev,
struct task_struct *task) { }
static inline void
perf_event_task_sched_out(struct task_struct *prev,
struct task_struct *next) { }
static inline int perf_event_init_task(struct task_struct *child,
u64 clone_flags) { return 0; }
static inline void perf_event_exit_task(struct task_struct *child) { }
static inline void perf_event_free_task(struct task_struct *task) { }
static inline void perf_event_delayed_put(struct task_struct *task) { }
static inline struct file *perf_event_get(unsigned int fd) { return ERR_PTR(-EINVAL); }
static inline const struct perf_event *perf_get_event(struct file *file)
{
return ERR_PTR(-EINVAL);
}
static inline const struct perf_event_attr *perf_event_attrs(struct perf_event *event)
{
return ERR_PTR(-EINVAL);
}
static inline int perf_event_read_local(struct perf_event *event, u64 *value,
u64 *enabled, u64 *running)
{
return -EINVAL;
}
static inline void perf_event_print_debug(void) { }
static inline int perf_event_task_disable(void) { return -EINVAL; }
static inline int perf_event_task_enable(void) { return -EINVAL; }
static inline int perf_event_refresh(struct perf_event *event, int refresh)
{
return -EINVAL;
}
static inline void
perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) { }
static inline void
perf_bp_event(struct perf_event *event, void *data) { }
static inline int perf_register_guest_info_callbacks
(struct perf_guest_info_callbacks *callbacks) { return 0; }
static inline int perf_unregister_guest_info_callbacks
(struct perf_guest_info_callbacks *callbacks) { return 0; }
static inline void perf_event_mmap(struct vm_area_struct *vma) { }
typedef int (perf_ksymbol_get_name_f)(char *name, int name_len, void *data);
static inline void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len,
bool unregister, const char *sym) { }
static inline void perf_event_bpf_event(struct bpf_prog *prog,
enum perf_bpf_event_type type,
u16 flags) { }
static inline void perf_event_exec(void) { }
static inline void perf_event_comm(struct task_struct *tsk, bool exec) { }
static inline void perf_event_namespaces(struct task_struct *tsk) { }
static inline void perf_event_fork(struct task_struct *tsk) { }
static inline void perf_event_text_poke(const void *addr,
const void *old_bytes,
size_t old_len,
const void *new_bytes,
size_t new_len) { }
static inline void perf_event_init(void) { }
static inline int perf_swevent_get_recursion_context(void) { return -1; }
static inline void perf_swevent_put_recursion_context(int rctx) { }
static inline u64 perf_swevent_set_period(struct perf_event *event) { return 0; }
static inline void perf_event_enable(struct perf_event *event) { }
static inline void perf_event_disable(struct perf_event *event) { }
static inline int __perf_event_disable(void *info) { return -1; }
static inline void perf_event_task_tick(void) { }
static inline int perf_event_release_kernel(struct perf_event *event) { return 0; }
static inline int perf_event_period(struct perf_event *event, u64 value)
{
return -EINVAL;
}
static inline u64 perf_event_pause(struct perf_event *event, bool reset)
{
return 0;
}
#endif
#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
extern void perf_restore_debug_store(void);
#else
static inline void perf_restore_debug_store(void) { }
#endif
static __always_inline bool perf_raw_frag_last(const struct perf_raw_frag *frag)
{
return frag->pad < sizeof(u64);
}
#define perf_output_put(handle, x) perf_output_copy((handle), &(x), sizeof(x))
struct perf_pmu_events_attr {
struct device_attribute attr;
u64 id;
const char *event_str;
};
struct perf_pmu_events_ht_attr {
struct device_attribute attr;
u64 id;
const char *event_str_ht;
const char *event_str_noht;
};
struct perf_pmu_events_hybrid_attr {
struct device_attribute attr;
u64 id;
const char *event_str;
u64 pmu_type;
};
struct perf_pmu_format_hybrid_attr {
struct device_attribute attr;
u64 pmu_type;
};
ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr,
char *page);
#define PMU_EVENT_ATTR(_name, _var, _id, _show) \
static struct perf_pmu_events_attr _var = { \
.attr = __ATTR(_name, 0444, _show, NULL), \
.id = _id, \
};
#define PMU_EVENT_ATTR_STRING(_name, _var, _str) \
static struct perf_pmu_events_attr _var = { \
.attr = __ATTR(_name, 0444, perf_event_sysfs_show, NULL), \
.id = 0, \
.event_str = _str, \
};
#define PMU_EVENT_ATTR_ID(_name, _show, _id) \
(&((struct perf_pmu_events_attr[]) { \
{ .attr = __ATTR(_name, 0444, _show, NULL), \
.id = _id, } \
})[0].attr.attr)
#define PMU_FORMAT_ATTR(_name, _format) \
static ssize_t \
_name##_show(struct device *dev, \
struct device_attribute *attr, \
char *page) \
{ \
BUILD_BUG_ON(sizeof(_format) >= PAGE_SIZE); \
return sprintf(page, _format "\n"); \
} \
\
static struct device_attribute format_attr_##_name = __ATTR_RO(_name)
/* Performance counter hotplug functions */
#ifdef CONFIG_PERF_EVENTS
int perf_event_init_cpu(unsigned int cpu);
int perf_event_exit_cpu(unsigned int cpu);
#else
#define perf_event_init_cpu NULL
#define perf_event_exit_cpu NULL
#endif
extern void __weak arch_perf_update_userpage(struct perf_event *event,
struct perf_event_mmap_page *userpg,
u64 now);
#ifdef CONFIG_MMU
extern __weak u64 arch_perf_get_page_size(struct mm_struct *mm, unsigned long addr);
#endif
/*
* Snapshot branch stack on software events.
*
* Branch stack can be very useful in understanding software events. For
* example, when a long function, e.g. sys_perf_event_open, returns an
* errno, it is not obvious why the function failed. Branch stack could
* provide very helpful information in this type of scenarios.
*
* On software event, it is necessary to stop the hardware branch recorder
* fast. Otherwise, the hardware register/buffer will be flushed with
* entries of the triggering event. Therefore, static call is used to
* stop the hardware recorder.
*/
/*
* cnt is the number of entries allocated for entries.
* Return number of entries copied to .
*/
typedef int (perf_snapshot_branch_stack_t)(struct perf_branch_entry *entries,
unsigned int cnt);
DECLARE_STATIC_CALL(perf_snapshot_branch_stack, perf_snapshot_branch_stack_t);
#endif /* _LINUX_PERF_EVENT_H */