From: Namhyung Kim <namhyung@kernel.org>
To: Arnaldo Carvalho de Melo <acme@kernel.org>, Jiri Olsa <jolsa@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
LKML <linux-kernel@vger.kernel.org>,
Andi Kleen <ak@linux.intel.com>, Ian Rogers <irogers@google.com>,
Stephane Eranian <eranian@google.com>,
Song Liu <songliubraving@fb.com>
Subject: [PATCH 2/3] perf tools: Add cgroup_is_v2() helper
Date: Mon, 14 Jun 2021 18:17:23 -0700 [thread overview]
Message-ID: <20210615011724.672612-3-namhyung@kernel.org> (raw)
In-Reply-To: <20210615011724.672612-1-namhyung@kernel.org>
The cgroup_is_v2() is to check if the given subsystem is mounted on
cgroup v2 or not. It'll be used by BPF cgroup code later.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/util/cgroup.c | 19 +++++++++++++++++++
tools/perf/util/cgroup.h | 2 ++
2 files changed, 21 insertions(+)
diff --git a/tools/perf/util/cgroup.c b/tools/perf/util/cgroup.c
index ef18c988c681..48ec79211270 100644
--- a/tools/perf/util/cgroup.c
+++ b/tools/perf/util/cgroup.c
@@ -9,6 +9,7 @@
#include <linux/zalloc.h>
#include <sys/types.h>
#include <sys/stat.h>
+#include <sys/statfs.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
@@ -70,6 +71,24 @@ int read_cgroup_id(struct cgroup *cgrp)
}
#endif /* HAVE_FILE_HANDLE */
+#ifndef CGROUP2_SUPER_MAGIC
+#define CGROUP2_SUPER_MAGIC 0x63677270
+#endif
+
+int cgroup_is_v2(const char *subsys)
+{
+ char mnt[PATH_MAX + 1];
+ struct statfs stbuf;
+
+ if (cgroupfs_find_mountpoint(mnt, PATH_MAX + 1, subsys))
+ return -1;
+
+ if (statfs(mnt, stbuf) < 0)
+ return -1;
+
+ return (stbuf.f_type == CGROUP2_SUPER_MAGIC);
+}
+
static struct cgroup *evlist__find_cgroup(struct evlist *evlist, const char *str)
{
struct evsel *counter;
diff --git a/tools/perf/util/cgroup.h b/tools/perf/util/cgroup.h
index 707adbe25123..1549ec2fd348 100644
--- a/tools/perf/util/cgroup.h
+++ b/tools/perf/util/cgroup.h
@@ -47,4 +47,6 @@ int read_cgroup_id(struct cgroup *cgrp)
}
#endif /* HAVE_FILE_HANDLE */
+int cgroup_is_v2(const char *subsys);
+
#endif /* __CGROUP_H__ */
--
2.32.0.272.g935e593368-goog
next prev parent reply other threads:[~2021-06-15 2:24 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-15 1:17 [PATCHSET v2 0/3] perf stat: Enable BPF counters with --for-each-cgroup Namhyung Kim
2021-06-15 1:17 ` [PATCH 1/3] perf tools: Add read_cgroup_id() function Namhyung Kim
2021-06-15 1:17 ` Namhyung Kim [this message]
2021-06-15 1:17 ` [PATCH 3/3] perf stat: Enable BPF counter with --for-each-cgroup Namhyung Kim
2021-06-16 15:14 ` [PATCHSET v2 0/3] perf stat: Enable BPF counters " Peter Zijlstra
2021-06-16 16:33 ` Namhyung Kim
2021-06-16 22:32 ` Peter Zijlstra
2021-06-17 6:33 ` Song Liu
2021-06-22 1:43 ` Namhyung Kim
2021-06-22 7:12 [PATCHSET v3 " Namhyung Kim
2021-06-22 7:12 ` [PATCH 2/3] perf tools: Add cgroup_is_v2() helper Namhyung Kim
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