linux/tools/perf/util/mem-events.c
Jiri Olsa 54fbad54eb perf mem record: Check for memory events support
Check if current kernel support available memory events and display the
status within -e  list option:

  $ perf mem record -e list
  ldlat-loads  : available
  ldlat-stores : available

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1456303616-26926-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-02-24 10:10:59 -03:00

81 lines
1.5 KiB
C

#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <api/fs/fs.h>
#include "mem-events.h"
#include "debug.h"
#define E(t, n, s) { .tag = t, .name = n, .sysfs_name = s }
struct perf_mem_event perf_mem_events[PERF_MEM_EVENTS__MAX] = {
E("ldlat-loads", "cpu/mem-loads,ldlat=30/P", "mem-loads"),
E("ldlat-stores", "cpu/mem-stores/P", "mem-stores"),
};
#undef E
#undef E
int perf_mem_events__parse(const char *str)
{
char *tok, *saveptr = NULL;
bool found = false;
char *buf;
int j;
/* We need buffer that we know we can write to. */
buf = malloc(strlen(str) + 1);
if (!buf)
return -ENOMEM;
strcpy(buf, str);
tok = strtok_r((char *)buf, ",", &saveptr);
while (tok) {
for (j = 0; j < PERF_MEM_EVENTS__MAX; j++) {
struct perf_mem_event *e = &perf_mem_events[j];
if (strstr(e->tag, tok))
e->record = found = true;
}
tok = strtok_r(NULL, ",", &saveptr);
}
free(buf);
if (found)
return 0;
pr_err("failed: event '%s' not found, use '-e list' to get list of available events\n", str);
return -1;
}
int perf_mem_events__init(void)
{
const char *mnt = sysfs__mount();
bool found = false;
int j;
if (!mnt)
return -ENOENT;
for (j = 0; j < PERF_MEM_EVENTS__MAX; j++) {
char path[PATH_MAX];
struct perf_mem_event *e = &perf_mem_events[j];
struct stat st;
scnprintf(path, PATH_MAX, "%s/devices/cpu/events/%s",
mnt, e->sysfs_name);
if (!stat(path, &st))
e->supported = found = true;
}
return found ? 0 : -ENOENT;
}