From: Namhyung Kim <namhyung@kernel.org>
To: Ingo Molnar <mingo@kernel.org>,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>, Mark Rutland <mark.rutland@arm.com>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Stephane Eranian <eranian@google.com>,
LKML <linux-kernel@vger.kernel.org>,
linux-perf-users@vger.kernel.org
Subject: [PATCH 07/10] perf record: Support synthesizing cgroup events
Date: Mon, 24 Feb 2020 13:37:46 +0900 [thread overview]
Message-ID: <20200224043749.69466-8-namhyung@kernel.org> (raw)
In-Reply-To: <20200224043749.69466-1-namhyung@kernel.org>
Synthesize cgroup events by iterating cgroup filesystem directories.
The cgroup event only saves the portion of cgroup path after the mount
point and the cgroup id (which actually is a file handle).
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/builtin-record.c | 5 ++
tools/perf/util/cgroup.h | 1 +
tools/perf/util/event.c | 1 +
tools/perf/util/synthetic-events.c | 113 +++++++++++++++++++++++++++++
tools/perf/util/synthetic-events.h | 1 +
tools/perf/util/tool.h | 1 +
6 files changed, 122 insertions(+)
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 4c301466101b..2802de9538ff 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1397,6 +1397,11 @@ static int record__synthesize(struct record *rec, bool tail)
if (err < 0)
pr_warning("Couldn't synthesize bpf events.\n");
+ err = perf_event__synthesize_cgroups(tool, process_synthesized_event,
+ machine);
+ if (err < 0)
+ pr_warning("Couldn't synthesize cgroup events.\n");
+
err = __machine__synthesize_threads(machine, tool, &opts->target, rec->evlist->core.threads,
process_synthesized_event, opts->sample_address,
1);
diff --git a/tools/perf/util/cgroup.h b/tools/perf/util/cgroup.h
index e98d5975fe55..8337ec452c66 100644
--- a/tools/perf/util/cgroup.h
+++ b/tools/perf/util/cgroup.h
@@ -18,6 +18,7 @@ struct cgroup {
extern int nr_cgroups; /* number of explicit cgroups defined */
+int cgroupfs_find_mountpoint(char *buf, size_t maxlen);
struct cgroup *cgroup__get(struct cgroup *cgroup);
void cgroup__put(struct cgroup *cgroup);
diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index 824c038e5c33..28801c867f39 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -33,6 +33,7 @@
#include "bpf-event.h"
#include "tool.h"
#include "../perf.h"
+#include "cgroup.h"
static const char *perf_event__names[] = {
[0] = "TOTAL",
diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c
index cd336eb8886b..e826ccad1ebd 100644
--- a/tools/perf/util/synthetic-events.c
+++ b/tools/perf/util/synthetic-events.c
@@ -16,6 +16,7 @@
#include "util/synthetic-events.h"
#include "util/target.h"
#include "util/time-utils.h"
+#include "util/cgroup.h"
#include <linux/bitops.h>
#include <linux/kernel.h>
#include <linux/string.h>
@@ -413,6 +414,118 @@ int perf_event__synthesize_mmap_events(struct perf_tool *tool,
return rc;
}
+static int perf_event__synthesize_cgroup(struct perf_tool *tool,
+ union perf_event *event,
+ char *path, size_t mount_len,
+ perf_event__handler_t process,
+ struct machine *machine)
+{
+ size_t event_size = sizeof(event->cgroup) - sizeof(event->cgroup.path);
+ size_t path_len = strlen(path) - mount_len + 1;
+ struct {
+ struct file_handle fh;
+ uint64_t cgroup_id;
+ } handle;
+ int mount_id;
+
+ while (path_len % sizeof(u64))
+ path[mount_len + path_len++] = '\0';
+
+ memset(&event->cgroup, 0, event_size);
+
+ event->cgroup.header.type = PERF_RECORD_CGROUP;
+ event->cgroup.header.size = event_size + path_len + machine->id_hdr_size;
+
+ handle.fh.handle_bytes = sizeof(handle.cgroup_id);
+ if (name_to_handle_at(AT_FDCWD, path, &handle.fh, &mount_id, 0) < 0) {
+ pr_debug("stat failed: %s\n", path);
+ return -1;
+ }
+
+ event->cgroup.id = handle.cgroup_id;
+ strncpy(event->cgroup.path, path + mount_len, path_len);
+ memset(event->cgroup.path + path_len, 0, machine->id_hdr_size);
+
+ if (perf_tool__process_synth_event(tool, event, machine, process) < 0) {
+ pr_debug("process synth event failed\n");
+ return -1;
+ }
+
+ return 0;
+}
+
+static int perf_event__walk_cgroup_tree(struct perf_tool *tool,
+ union perf_event *event,
+ char *path, size_t mount_len,
+ perf_event__handler_t process,
+ struct machine *machine)
+{
+ size_t pos = strlen(path);
+ DIR *d;
+ struct dirent *dent;
+ int ret = 0;
+
+ if (perf_event__synthesize_cgroup(tool, event, path, mount_len,
+ process, machine) < 0)
+ return -1;
+
+ d = opendir(path);
+ if (d == NULL) {
+ pr_debug("failed to open directory: %s\n", path);
+ return -1;
+ }
+
+ while ((dent = readdir(d)) != NULL) {
+ if (dent->d_type != DT_DIR)
+ continue;
+ if (!strcmp(dent->d_name, ".") ||
+ !strcmp(dent->d_name, ".."))
+ continue;
+
+ /* any sane path should be less than PATH_MAX */
+ if (strlen(path) + strlen(dent->d_name) + 1 >= PATH_MAX)
+ continue;
+
+ if (path[pos - 1] != '/')
+ strcat(path, "/");
+ strcat(path, dent->d_name);
+
+ ret = perf_event__walk_cgroup_tree(tool, event, path,
+ mount_len, process, machine);
+ if (ret < 0)
+ break;
+
+ path[pos] = '\0';
+ }
+
+ closedir(d);
+ return ret;
+}
+
+int perf_event__synthesize_cgroups(struct perf_tool *tool,
+ perf_event__handler_t process,
+ struct machine *machine)
+{
+ union perf_event event;
+ char cgrp_root[PATH_MAX];
+ size_t mount_len; /* length of mount point in the path */
+
+ if (cgroupfs__mountpoint(cgrp_root, PATH_MAX, "perf_event") < 0) {
+ pr_debug("cannot find cgroup mount point\n");
+ return -1;
+ }
+
+ mount_len = strlen(cgrp_root);
+ /* make sure the path starts with a slash (after mount point) */
+ strcat(cgrp_root, "/");
+
+ if (perf_event__walk_cgroup_tree(tool, &event, cgrp_root, mount_len,
+ process, machine) < 0)
+ return -1;
+
+ return 0;
+}
+
int perf_event__synthesize_modules(struct perf_tool *tool, perf_event__handler_t process,
struct machine *machine)
{
diff --git a/tools/perf/util/synthetic-events.h b/tools/perf/util/synthetic-events.h
index baead0cdc381..e7a3e9589738 100644
--- a/tools/perf/util/synthetic-events.h
+++ b/tools/perf/util/synthetic-events.h
@@ -45,6 +45,7 @@ int perf_event__synthesize_kernel_mmap(struct perf_tool *tool, perf_event__handl
int perf_event__synthesize_mmap_events(struct perf_tool *tool, union perf_event *event, pid_t pid, pid_t tgid, perf_event__handler_t process, struct machine *machine, bool mmap_data);
int perf_event__synthesize_modules(struct perf_tool *tool, perf_event__handler_t process, struct machine *machine);
int perf_event__synthesize_namespaces(struct perf_tool *tool, union perf_event *event, pid_t pid, pid_t tgid, perf_event__handler_t process, struct machine *machine);
+int perf_event__synthesize_cgroups(struct perf_tool *tool, perf_event__handler_t process, struct machine *machine);
int perf_event__synthesize_sample(union perf_event *event, u64 type, u64 read_format, const struct perf_sample *sample);
int perf_event__synthesize_stat_config(struct perf_tool *tool, struct perf_stat_config *config, perf_event__handler_t process, struct machine *machine);
int perf_event__synthesize_stat_events(struct perf_stat_config *config, struct perf_tool *tool, struct evlist *evlist, perf_event__handler_t process, bool attrs);
diff --git a/tools/perf/util/tool.h b/tools/perf/util/tool.h
index 472ef5eb4068..3fb67bd31e4a 100644
--- a/tools/perf/util/tool.h
+++ b/tools/perf/util/tool.h
@@ -79,6 +79,7 @@ struct perf_tool {
bool ordered_events;
bool ordering_requires_timestamps;
bool namespace_events;
+ bool cgroup_events;
bool no_warn;
enum show_feature_header show_feat_hdr;
};
--
2.25.0.265.gbab2e86ba0-goog
next prev parent reply other threads:[~2020-02-24 4:38 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-24 4:37 [PATCHSET 00/10] perf: Improve cgroup profiling (v5) Namhyung Kim
2020-02-24 4:37 ` [PATCH 01/10] perf/core: Add PERF_RECORD_CGROUP event Namhyung Kim
2020-02-24 4:37 ` [PATCH 02/10] perf/core: Add PERF_SAMPLE_CGROUP feature Namhyung Kim
2020-02-24 4:37 ` [PATCH 03/10] tools lib api fs: Move cgroupsfs__mountpoint() Namhyung Kim
2020-02-24 4:37 ` [PATCH 04/10] perf tools: Basic support for CGROUP event Namhyung Kim
2020-02-24 4:37 ` [PATCH 05/10] perf tools: Maintain cgroup hierarchy Namhyung Kim
2020-02-24 4:37 ` [PATCH 06/10] perf report: Add 'cgroup' sort key Namhyung Kim
2020-03-06 14:10 ` Jiri Olsa
2020-02-24 4:37 ` Namhyung Kim [this message]
2020-03-06 14:14 ` [PATCH 07/10] perf record: Support synthesizing cgroup events Jiri Olsa
2020-03-06 14:15 ` Jiri Olsa
2020-02-24 4:37 ` [PATCH 08/10] perf record: Add --all-cgroups option Namhyung Kim
2020-02-24 4:37 ` [PATCH 09/10] perf top: " Namhyung Kim
2020-02-24 4:37 ` [PATCH 10/10] perf script: Add --show-cgroup-events option Namhyung Kim
2020-03-06 15:05 ` [PATCHSET 00/10] perf: Improve cgroup profiling (v5) Jiri Olsa
2020-03-22 23:58 ` Namhyung Kim
2020-03-24 16:34 ` Tejun Heo
2020-03-24 20:15 ` Peter Zijlstra
2020-03-24 21:24 ` Arnaldo Melo
2020-03-25 10:24 ` Namhyung Kim
2020-03-25 12:17 ` Arnaldo Carvalho de Melo
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200224043749.69466-8-namhyung@kernel.org \
--to=namhyung@kernel.org \
--cc=a.p.zijlstra@chello.nl \
--cc=acme@kernel.org \
--cc=alexander.shishkin@linux.intel.com \
--cc=eranian@google.com \
--cc=jolsa@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-perf-users@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=mingo@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
Powered by JetHome