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authorNamhyung Kim <namhyung@kernel.org>2020-03-25 21:45:29 +0900
committerArnaldo Carvalho de Melo <acme@redhat.com>2020-03-27 10:41:44 -0300
commit6546b19f95acc986807de981402bbac6b3a94b0f (patch)
treed1d33094a9ed4d73d68f93fc92b954ca5d553caf /init
parent96aaab686505c449e24d76e76507290dcc30e008 (diff)
downloadlinux-6546b19f95acc986807de981402bbac6b3a94b0f.tar.bz2
perf/core: Add PERF_SAMPLE_CGROUP feature
The PERF_SAMPLE_CGROUP bit is to save (perf_event) cgroup information in the sample. It will add a 64-bit id to identify current cgroup and it's the file handle in the cgroup file system. Userspace should use this information with PERF_RECORD_CGROUP event to match which cgroup it belongs. I put it before PERF_SAMPLE_AUX for simplicity since it just needs a 64-bit word. But if we want bigger samples, I can work on that direction too. Committer testing: $ pahole perf_sample_data | grep -w cgroup -B5 -A5 /* --- cacheline 4 boundary (256 bytes) was 56 bytes ago --- */ struct perf_regs regs_intr; /* 312 16 */ /* --- cacheline 5 boundary (320 bytes) was 8 bytes ago --- */ u64 stack_user_size; /* 328 8 */ u64 phys_addr; /* 336 8 */ u64 cgroup; /* 344 8 */ /* size: 384, cachelines: 6, members: 22 */ /* padding: 32 */ }; $ Signed-off-by: Namhyung Kim <namhyung@kernel.org> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Tejun Heo <tj@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Zefan Li <lizefan@huawei.com> Link: http://lore.kernel.org/lkml/20200325124536.2800725-3-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'init')
-rw-r--r--init/Kconfig3
1 files changed, 2 insertions, 1 deletions
diff --git a/init/Kconfig b/init/Kconfig
index 20a6ac33761c..7766b06a0038 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1027,7 +1027,8 @@ config CGROUP_PERF
help
This option extends the perf per-cpu mode to restrict monitoring
to threads which belong to the cgroup specified and run on the
- designated cpu.
+ designated cpu. Or this can be used to have cgroup ID in samples
+ so that it can monitor performance events among cgroups.
Say N if unsure.