mirror of
https://github.com/torvalds/linux.git
synced 2024-12-05 18:41:23 +00:00
aa8cc2f6b5
Both do the same thing, the later is the one we get from linux/stringify.h, i.e. we now use the same function name/practice as the kernel sources. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-w2sxa5o4bfx7fjrd5mu4zmke@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
187 lines
3.4 KiB
C
187 lines
3.4 KiB
C
#include "util.h"
|
|
#include "../perf.h"
|
|
#include <subcmd/parse-options.h>
|
|
#include "evsel.h"
|
|
#include "cgroup.h"
|
|
#include "evlist.h"
|
|
#include <linux/stringify.h>
|
|
|
|
int nr_cgroups;
|
|
|
|
static int
|
|
cgroupfs_find_mountpoint(char *buf, size_t maxlen)
|
|
{
|
|
FILE *fp;
|
|
char mountpoint[PATH_MAX + 1], tokens[PATH_MAX + 1], type[PATH_MAX + 1];
|
|
char path_v1[PATH_MAX + 1], path_v2[PATH_MAX + 2], *path;
|
|
char *token, *saved_ptr = NULL;
|
|
|
|
fp = fopen("/proc/mounts", "r");
|
|
if (!fp)
|
|
return -1;
|
|
|
|
/*
|
|
* in order to handle split hierarchy, we need to scan /proc/mounts
|
|
* and inspect every cgroupfs mount point to find one that has
|
|
* perf_event subsystem
|
|
*/
|
|
path_v1[0] = '\0';
|
|
path_v2[0] = '\0';
|
|
|
|
while (fscanf(fp, "%*s %"__stringify(PATH_MAX)"s %"__stringify(PATH_MAX)"s %"
|
|
__stringify(PATH_MAX)"s %*d %*d\n",
|
|
mountpoint, type, tokens) == 3) {
|
|
|
|
if (!path_v1[0] && !strcmp(type, "cgroup")) {
|
|
|
|
token = strtok_r(tokens, ",", &saved_ptr);
|
|
|
|
while (token != NULL) {
|
|
if (!strcmp(token, "perf_event")) {
|
|
strcpy(path_v1, mountpoint);
|
|
break;
|
|
}
|
|
token = strtok_r(NULL, ",", &saved_ptr);
|
|
}
|
|
}
|
|
|
|
if (!path_v2[0] && !strcmp(type, "cgroup2"))
|
|
strcpy(path_v2, mountpoint);
|
|
|
|
if (path_v1[0] && path_v2[0])
|
|
break;
|
|
}
|
|
fclose(fp);
|
|
|
|
if (path_v1[0])
|
|
path = path_v1;
|
|
else if (path_v2[0])
|
|
path = path_v2;
|
|
else
|
|
return -1;
|
|
|
|
if (strlen(path) < maxlen) {
|
|
strcpy(buf, path);
|
|
return 0;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
static int open_cgroup(char *name)
|
|
{
|
|
char path[PATH_MAX + 1];
|
|
char mnt[PATH_MAX + 1];
|
|
int fd;
|
|
|
|
|
|
if (cgroupfs_find_mountpoint(mnt, PATH_MAX + 1))
|
|
return -1;
|
|
|
|
snprintf(path, PATH_MAX, "%s/%s", mnt, name);
|
|
|
|
fd = open(path, O_RDONLY);
|
|
if (fd == -1)
|
|
fprintf(stderr, "no access to cgroup %s\n", path);
|
|
|
|
return fd;
|
|
}
|
|
|
|
static int add_cgroup(struct perf_evlist *evlist, char *str)
|
|
{
|
|
struct perf_evsel *counter;
|
|
struct cgroup_sel *cgrp = NULL;
|
|
int n;
|
|
/*
|
|
* check if cgrp is already defined, if so we reuse it
|
|
*/
|
|
evlist__for_each_entry(evlist, counter) {
|
|
cgrp = counter->cgrp;
|
|
if (!cgrp)
|
|
continue;
|
|
if (!strcmp(cgrp->name, str))
|
|
break;
|
|
|
|
cgrp = NULL;
|
|
}
|
|
|
|
if (!cgrp) {
|
|
cgrp = zalloc(sizeof(*cgrp));
|
|
if (!cgrp)
|
|
return -1;
|
|
|
|
cgrp->name = str;
|
|
|
|
cgrp->fd = open_cgroup(str);
|
|
if (cgrp->fd == -1) {
|
|
free(cgrp);
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* find corresponding event
|
|
* if add cgroup N, then need to find event N
|
|
*/
|
|
n = 0;
|
|
evlist__for_each_entry(evlist, counter) {
|
|
if (n == nr_cgroups)
|
|
goto found;
|
|
n++;
|
|
}
|
|
if (refcount_read(&cgrp->refcnt) == 0)
|
|
free(cgrp);
|
|
|
|
return -1;
|
|
found:
|
|
refcount_inc(&cgrp->refcnt);
|
|
counter->cgrp = cgrp;
|
|
return 0;
|
|
}
|
|
|
|
void close_cgroup(struct cgroup_sel *cgrp)
|
|
{
|
|
if (cgrp && refcount_dec_and_test(&cgrp->refcnt)) {
|
|
close(cgrp->fd);
|
|
zfree(&cgrp->name);
|
|
free(cgrp);
|
|
}
|
|
}
|
|
|
|
int parse_cgroups(const struct option *opt __maybe_unused, const char *str,
|
|
int unset __maybe_unused)
|
|
{
|
|
struct perf_evlist *evlist = *(struct perf_evlist **)opt->value;
|
|
const char *p, *e, *eos = str + strlen(str);
|
|
char *s;
|
|
int ret;
|
|
|
|
if (list_empty(&evlist->entries)) {
|
|
fprintf(stderr, "must define events before cgroups\n");
|
|
return -1;
|
|
}
|
|
|
|
for (;;) {
|
|
p = strchr(str, ',');
|
|
e = p ? p : eos;
|
|
|
|
/* allow empty cgroups, i.e., skip */
|
|
if (e - str) {
|
|
/* termination added */
|
|
s = strndup(str, e - str);
|
|
if (!s)
|
|
return -1;
|
|
ret = add_cgroup(evlist, s);
|
|
if (ret) {
|
|
free(s);
|
|
return -1;
|
|
}
|
|
}
|
|
/* nr_cgroups is increased een for empty cgroups */
|
|
nr_cgroups++;
|
|
if (!p)
|
|
break;
|
|
str = p+1;
|
|
}
|
|
return 0;
|
|
}
|