[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20190828073130.83800-7-namhyung@kernel.org>
Date: Wed, 28 Aug 2019 16:31:27 +0900
From: Namhyung Kim <namhyung@...nel.org>
To: Ingo Molnar <mingo@...nel.org>,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Arnaldo Carvalho de Melo <acme@...nel.org>
Cc: LKML <linux-kernel@...r.kernel.org>, Jiri Olsa <jolsa@...hat.com>,
Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
Stephane Eranian <eranian@...gle.com>
Subject: [PATCH 6/9] perf record: Support synthesizing cgroup events
Synthesize cgroup events by iterating cgroup filesystem directories.
The cgroup event only saves the portion of cgroup path after the mount
point and the inode number.
Signed-off-by: Namhyung Kim <namhyung@...nel.org>
---
tools/perf/builtin-record.c | 5 ++
tools/perf/util/cgroup.c | 3 +-
tools/perf/util/cgroup.h | 1 +
tools/perf/util/event.c | 115 ++++++++++++++++++++++++++++++++++++
tools/perf/util/event.h | 4 ++
tools/perf/util/tool.h | 1 +
6 files changed, 127 insertions(+), 2 deletions(-)
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 359bb8f33e57..a6e3c4413b39 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -1318,6 +1318,11 @@ 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.c b/tools/perf/util/cgroup.c
index 8e4c26ea5078..274f0f29c72d 100644
--- a/tools/perf/util/cgroup.c
+++ b/tools/perf/util/cgroup.c
@@ -14,8 +14,7 @@ int nr_cgroups;
static struct rb_root cgroup_tree = RB_ROOT;
-static int
-cgroupfs_find_mountpoint(char *buf, size_t maxlen)
+int cgroupfs_find_mountpoint(char *buf, size_t maxlen)
{
FILE *fp;
char mountpoint[PATH_MAX + 1], tokens[PATH_MAX + 1], type[PATH_MAX + 1];
diff --git a/tools/perf/util/cgroup.h b/tools/perf/util/cgroup.h
index 11a8b187ec09..755f9712eda4 100644
--- a/tools/perf/util/cgroup.h
+++ b/tools/perf/util/cgroup.h
@@ -17,6 +17,7 @@ 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 c19b00c1fc26..9e71b9561f72 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -29,6 +29,7 @@
#include "stat.h"
#include "session.h"
#include "bpf-event.h"
+#include "cgroup.h"
#define DEFAULT_PROC_MAP_PARSE_TIMEOUT 500
@@ -296,6 +297,120 @@ int perf_event__synthesize_namespaces(struct perf_tool *tool,
return 0;
}
+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 stat64 stbuf;
+
+ 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;
+
+ if (stat64(path, &stbuf) < 0) {
+ pr_debug("stat failed: %s\n", path);
+ return -1;
+ }
+
+ event->cgroup.ino = stbuf.st_ino;
+ event->cgroup.path_len = path_len;
+ 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;
+
+ 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;
+ size_t mount_len; /* length of mount point in the path */
+ int ret = -1;
+
+ cgrp_root = malloc(PATH_MAX);
+ if (cgrp_root == NULL)
+ return -1;
+
+ if (cgroupfs_find_mountpoint(cgrp_root, PATH_MAX) < 0) {
+ pr_debug("cannot find cgroup mount point\n");
+ goto out;
+ }
+
+ 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)
+ goto out;
+
+ ret = 0;
+
+out:
+ free(cgrp_root);
+
+ return ret;
+}
+
static int perf_event__synthesize_fork(struct perf_tool *tool,
union perf_event *event,
pid_t pid, pid_t tgid, pid_t ppid,
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index 0170435fd1e8..b4c4da69a771 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -735,6 +735,10 @@ int perf_event__synthesize_namespaces(struct perf_tool *tool,
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_mmap_events(struct perf_tool *tool,
union perf_event *event,
pid_t pid, pid_t tgid,
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;
};
--
2.23.0.187.g17f5b7556c-goog
Powered by blists - more mailing lists