kernel_optimize_test/tools/perf/util/mmap.h
Wang Nan 8eb7a1fe31 perf mmap: Remove overwrite and check_messup from mmap read
All perf_mmap__read_forward() read from read-write ring buffer, so no
need check_messup. Reading from backward ring buffer doesn't require
check_messup because it never mess up. Cleanup arguments lists.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Link: http://lkml.kernel.org/r/20171203020044.81680-6-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-12-05 15:43:54 -03:00

98 lines
2.6 KiB
C

#ifndef __PERF_MMAP_H
#define __PERF_MMAP_H 1
#include <linux/compiler.h>
#include <linux/refcount.h>
#include <linux/types.h>
#include <asm/barrier.h>
#include <stdbool.h>
#include "auxtrace.h"
#include "event.h"
/**
* struct perf_mmap - perf's ring buffer mmap details
*
* @refcnt - e.g. code using PERF_EVENT_IOC_SET_OUTPUT to share this
*/
struct perf_mmap {
void *base;
int mask;
int fd;
refcount_t refcnt;
u64 prev;
struct auxtrace_mmap auxtrace_mmap;
char event_copy[PERF_SAMPLE_MAX_SIZE] __aligned(8);
};
/*
* State machine of bkw_mmap_state:
*
* .________________(forbid)_____________.
* | V
* NOTREADY --(0)--> RUNNING --(1)--> DATA_PENDING --(2)--> EMPTY
* ^ ^ | ^ |
* | |__(forbid)____/ |___(forbid)___/|
* | |
* \_________________(3)_______________/
*
* NOTREADY : Backward ring buffers are not ready
* RUNNING : Backward ring buffers are recording
* DATA_PENDING : We are required to collect data from backward ring buffers
* EMPTY : We have collected data from backward ring buffers.
*
* (0): Setup backward ring buffer
* (1): Pause ring buffers for reading
* (2): Read from ring buffers
* (3): Resume ring buffers for recording
*/
enum bkw_mmap_state {
BKW_MMAP_NOTREADY,
BKW_MMAP_RUNNING,
BKW_MMAP_DATA_PENDING,
BKW_MMAP_EMPTY,
};
struct mmap_params {
int prot, mask;
struct auxtrace_mmap_params auxtrace_mp;
};
int perf_mmap__mmap(struct perf_mmap *map, struct mmap_params *mp, int fd);
void perf_mmap__munmap(struct perf_mmap *map);
void perf_mmap__get(struct perf_mmap *map);
void perf_mmap__put(struct perf_mmap *map);
void perf_mmap__consume(struct perf_mmap *map, bool overwrite);
void perf_mmap__read_catchup(struct perf_mmap *md);
static inline u64 perf_mmap__read_head(struct perf_mmap *mm)
{
struct perf_event_mmap_page *pc = mm->base;
u64 head = ACCESS_ONCE(pc->data_head);
rmb();
return head;
}
static inline void perf_mmap__write_tail(struct perf_mmap *md, u64 tail)
{
struct perf_event_mmap_page *pc = md->base;
/*
* ensure all reads are done before we write the tail out.
*/
mb();
pc->data_tail = tail;
}
union perf_event *perf_mmap__read_forward(struct perf_mmap *map);
union perf_event *perf_mmap__read_backward(struct perf_mmap *map);
int perf_mmap__push(struct perf_mmap *md, bool backward,
void *to, int push(void *to, void *buf, size_t size));
size_t perf_mmap__mmap_len(struct perf_mmap *map);
#endif /*__PERF_MMAP_H */