To make the command line even more compact with cgroups, support regex
pattern matching in cgroup names.
$ perf stat -a -e cpu-clock,cycles --for-each-cgroup '^.$' sleep 1
Performance counter stats for 'system wide':
992.90 msec cpu-clock A #0.992 CPUs utilized
4,155,444,322 cyclesA #4.204 GHz
(100.00%)
988.53 msec cpu-clock B #0.988 CPUs utilized
4,137,114,788 cyclesB #4.185 GHz
(100.00%)
983.94 msec cpu-clock C #0.983 CPUs utilized
4,117,862,551 cyclesC #4.166 GHz
(99.99%)
1.000975519 seconds time elapsed
Signed-off-by: Namhyung Kim
---
tools/perf/util/cgroup.c | 192 ++-
1 file changed, 168 insertions(+), 24 deletions(-)
diff --git a/tools/perf/util/cgroup.c b/tools/perf/util/cgroup.c
index b81324a13a2b..127c2411fb9f 100644
--- a/tools/perf/util/cgroup.c
+++ b/tools/perf/util/cgroup.c
@@ -13,9 +13,19 @@
#include
#include
#include
+#include
+#include
int nr_cgroups;
+/* used to match cgroup name with patterns */
+struct cgroup_name {
+ struct list_head list;
+ bool used;
+ char name[];
+};
+static LIST_HEAD(cgroup_list);
+
static int open_cgroup(const char *name)
{
char path[PATH_MAX + 1];
@@ -149,6 +159,137 @@ void evlist__set_default_cgroup(struct evlist *evlist,
struct cgroup *cgroup)
evsel__set_default_cgroup(evsel, cgroup);
}
+/* helper function for ftw() in match_cgroups and list_cgroups */
+static int add_cgroup_name(const char *fpath, const struct stat *sb
__maybe_unused,
+ int typeflag)
+{
+ struct cgroup_name *cn;
+
+ if (typeflag != FTW_D)
+ return 0;
+
+ cn = malloc(sizeof(*cn) + strlen(fpath) + 1);
+ if (cn == NULL)
+ return -1;
+
+ cn->used = false;
+ strcpy(cn->name, fpath);
+
+ list_add_tail(&cn->list, &cgroup_list);
+ return 0;
+}
+
+static void release_cgroup_list(void)
+{
+ struct cgroup_name *cn;
+
+ while (!list_empty(&cgroup_list)) {
+ cn = list_first_entry(&cgroup_list, struct cgroup_name, list);
+ list_del(&cn->list);
+ free(cn);
+ }
+}
+
+/* collect given cgroups only */
+static int list_cgroups(const char *str)
+{
+ const char *p, *e, *eos = str + strlen(str);
+ struct cgroup_name *cn;
+ char *s;
+
+ /* use given name as is - for testing purpose */
+ for (;;) {
+ p = strchr(str, ',');
+ e = p ? p : eos;
+
+ if (e - str) {
+ int ret;
+
+ s = strndup(str, e - str);
+ if (!s)
+ return -1;
+ /* pretend if it's added by ftw() */
+ ret = add_cgroup_name(s, NULL, FTW_D);
+ free(s);
+ if (ret)
+ return -1;
+ } else {
+ if (add_cgroup_name("", NULL, FTW_D) < 0)
+ return -1;
+ }
+
+ if (!p)
+ break;
+ str = p+1;
+ }
+
+ /* these groups will be used */
+ list_for_each_entry(cn, &cgroup_list, list)
+ cn->used = true;
+
+ return 0;
+}
+
+/* collect all cgroups first and then match with the pattern */
+static int match_cgroups(const char *str)
+{
+ char mnt[PATH_MAX];
+ const char *p, *e, *eos = str + strlen(str);
+ struct cgroup_name *cn;
+ regex_t reg;
+ int prefix_len;
+ char *s;
+
+ if (cgroupfs_find_mountpoint(mnt, sizeof(mnt), "perf_event"))
+ return -1;
+
+ /* cgroup_name will have a full path, skip the root directory */
+ prefix_len = strlen(mnt);
+
+ /* collect all cgroups in the cgroup_list */
+ if (ftw(mnt, add_cgroup_name, 20) < 0)
+ 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;
+ if (regcomp(®, s, REG_NOSUB)) {
+ free(s);
+ return -1;
+ }
+
+ /* check cgroup name with the pattern */
+ list_for_each_entry(cn, &cgroup_list, list) {
+ char *name = cn->name + prefix_len;
+
+ if (name[0] == '/' && n
