diff options
| author | Namhyung Kim <namhyung@kernel.org> | 2020-03-25 21:45:29 +0900 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2020-03-27 10:41:44 -0300 |
| commit | 6546b19f95acc986807de981402bbac6b3a94b0f (patch) | |
| tree | d1d33094a9ed4d73d68f93fc92b954ca5d553caf /kernel/events | |
| parent | 96aaab686505c449e24d76e76507290dcc30e008 (diff) | |
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 'kernel/events')
| -rw-r--r-- | kernel/events/core.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index 994932d5e474..1569979c8912 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -1862,6 +1862,9 @@ static void __perf_event_header_size(struct perf_event *event, u64 sample_type) if (sample_type & PERF_SAMPLE_PHYS_ADDR) size += sizeof(data->phys_addr); + if (sample_type & PERF_SAMPLE_CGROUP) + size += sizeof(data->cgroup); + event->header_size = size; } @@ -6867,6 +6870,9 @@ void perf_output_sample(struct perf_output_handle *handle, if (sample_type & PERF_SAMPLE_PHYS_ADDR) perf_output_put(handle, data->phys_addr); + if (sample_type & PERF_SAMPLE_CGROUP) + perf_output_put(handle, data->cgroup); + if (sample_type & PERF_SAMPLE_AUX) { perf_output_put(handle, data->aux_size); @@ -7066,6 +7072,16 @@ void perf_prepare_sample(struct perf_event_header *header, if (sample_type & PERF_SAMPLE_PHYS_ADDR) data->phys_addr = perf_virt_to_phys(data->addr); +#ifdef CONFIG_CGROUP_PERF + if (sample_type & PERF_SAMPLE_CGROUP) { + struct cgroup *cgrp; + + /* protected by RCU */ + cgrp = task_css_check(current, perf_event_cgrp_id, 1)->cgroup; + data->cgroup = cgroup_id(cgrp); + } +#endif + if (sample_type & PERF_SAMPLE_AUX) { u64 size; @@ -11264,6 +11280,12 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr, if (attr->sample_type & PERF_SAMPLE_REGS_INTR) ret = perf_reg_validate(attr->sample_regs_intr); + +#ifndef CONFIG_CGROUP_PERF + if (attr->sample_type & PERF_SAMPLE_CGROUP) + return -EINVAL; +#endif + out: return ret; |