diff options
author | Namhyung Kim <namhyung@kernel.org> | 2020-03-25 15:45:29 +0300 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2020-03-27 16:41:44 +0300 |
commit | 6546b19f95acc986807de981402bbac6b3a94b0f (patch) | |
tree | d1d33094a9ed4d73d68f93fc92b954ca5d553caf | |
parent | 96aaab686505c449e24d76e76507290dcc30e008 (diff) | |
download | linux-6546b19f95acc986807de981402bbac6b3a94b0f.tar.xz |
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>
-rw-r--r-- | include/linux/perf_event.h | 1 | ||||
-rw-r--r-- | include/uapi/linux/perf_event.h | 3 | ||||
-rw-r--r-- | init/Kconfig | 3 | ||||
-rw-r--r-- | kernel/events/core.c | 22 |
4 files changed, 27 insertions, 2 deletions
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 8768a39b5258..9c3e7619c929 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1020,6 +1020,7 @@ struct perf_sample_data { u64 stack_user_size; u64 phys_addr; + u64 cgroup; } ____cacheline_aligned; /* default value for data source */ diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h index de95f6c7b273..7b2d6fc9e6ed 100644 --- a/include/uapi/linux/perf_event.h +++ b/include/uapi/linux/perf_event.h @@ -142,8 +142,9 @@ enum perf_event_sample_format { PERF_SAMPLE_REGS_INTR = 1U << 18, PERF_SAMPLE_PHYS_ADDR = 1U << 19, PERF_SAMPLE_AUX = 1U << 20, + PERF_SAMPLE_CGROUP = 1U << 21, - PERF_SAMPLE_MAX = 1U << 21, /* non-ABI */ + PERF_SAMPLE_MAX = 1U << 22, /* non-ABI */ __PERF_SAMPLE_CALLCHAIN_EARLY = 1ULL << 63, /* non-ABI; internal use */ }; 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. 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; |