Commit Graph

4 Commits

Author SHA1 Message Date
Namhyung Kim 48859e5293 tools api fs: Cache cgroupfs mount point
Currently it parses the /proc file everytime it opens a file in the
cgroupfs.  Save the last result to avoid it (assuming it won't be
changed between the accesses).

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20201216090556.813996-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-02-17 15:09:08 -03:00
Namhyung Kim 6fd99b7f62 tools api fs: Diet cgroupfs_find_mountpoint()
Reduce the number of buffers and hopefully make it more efficient. :)

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20201216090556.813996-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-02-17 15:08:32 -03:00
Namhyung Kim 27ab1c1c06 tools api fs: Prefer cgroup v1 path in cgroupfs_find_mountpoint()
The cgroupfs_find_mountpoint() looks up the /proc/mounts file to find
a directory for the given cgroup subsystem.  It keeps both cgroup v1
and v2 path since there's a possibility of the mixed hierarchly.

But we can simply use v1 path if it's found as it will override the v2
hierarchy.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20201216090556.813996-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-02-17 15:06:22 -03:00
Namhyung Kim 7982a89851 tools lib api fs: Move cgroupsfs_find_mountpoint()
Move it from tools/perf/util/cgroup.c as it can be used by other places.
Note that cgroup filesystem is different from others since it's usually
mounted separately (in v1) for each subsystem.

I just copied the code with a little modification to pass a name of
subsystem.

Suggested-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200127100031.1368732-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-03-04 10:34:09 -03:00