[PATCH 11/19] perf record: Synthesize namespace events for current processes
From: Arnaldo Carvalho de Melo
Date: Tue Mar 14 2017 - 14:51:04 EST
From: Hari Bathini <hbathini@xxxxxxxxxxxxxxxxxx>
Synthesize PERF_RECORD_NAMESPACES events for processes that were running prior
to invocation of perf record. The data for this is taken from /proc/$PID/ns.
These changes make way for analyzing events with regard to namespaces.
Committer notes:
Check if 'tool' is NULL in perf_event__synthesize_namespaces(), as in the
test__mmap_thread_lookup case, i.e. 'perf test Lookup mmap thread".
Testing it:
# ps axH > /tmp/allthreads
# perf record -a --namespaces usleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.169 MB perf.data (8 samples) ]
# perf report -D | grep PERF_RECORD_NAMESPACES | wc -l
602
# wc -l /tmp/allthreads
601 /tmp/allthreads
# tail /tmp/allthreads
16951 pts/4 T 0:00 git rebase -i a033bf1bfacdaa25642e6bcc857a7d0f67cc3c92^
16952 pts/4 T 0:00 /bin/sh /usr/libexec/git-core/git-rebase -i a033bf1bfacdaa25642e6bcc857a7d0f67cc3c92^
17176 pts/4 T 0:00 git commit --amend --no-post-rewrite
17204 pts/4 T 0:00 vim /home/acme/git/linux/.git/COMMIT_EDITMSG
18939 ? S 0:00 [kworker/2:1]
18947 ? S 0:00 [kworker/3:0]
18974 ? S 0:00 [kworker/1:0]
19047 ? S 0:00 [kworker/0:1]
19152 pts/6 S+ 0:00 weechat
19153 pts/7 R+ 0:00 ps axH
# perf report -D | grep PERF_RECORD_NAMESPACES | tail
0 0 0x125068 [0xa0]: PERF_RECORD_NAMESPACES 17176/17176 - nr_namespaces: 7
0 0 0x1255b8 [0xa0]: PERF_RECORD_NAMESPACES 17204/17204 - nr_namespaces: 7
0 0 0x125df0 [0xa0]: PERF_RECORD_NAMESPACES 18939/18939 - nr_namespaces: 7
0 0 0x125f00 [0xa0]: PERF_RECORD_NAMESPACES 18947/18947 - nr_namespaces: 7
0 0 0x126010 [0xa0]: PERF_RECORD_NAMESPACES 18974/18974 - nr_namespaces: 7
0 0 0x126120 [0xa0]: PERF_RECORD_NAMESPACES 19047/19047 - nr_namespaces: 7
0 0 0x126230 [0xa0]: PERF_RECORD_NAMESPACES 19152/19152 - nr_namespaces: 7
0 0 0x129330 [0xa0]: PERF_RECORD_NAMESPACES 19154/19154 - nr_namespaces: 7
0 0 0x12a1f8 [0xa0]: PERF_RECORD_NAMESPACES 19155/19155 - nr_namespaces: 7
0 0 0x12b0b8 [0xa0]: PERF_RECORD_NAMESPACES 19155/19155 - nr_namespaces: 7
#
Humm, investigate why we got two record for the 19155 pid/tid...
Signed-off-by: Hari Bathini <hbathini@xxxxxxxxxxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxx>
Cc: Ananth N Mavinakayanahalli <ananth@xxxxxxxxxxxxxxxxxx>
Cc: Aravinda Prasad <aravinda@xxxxxxxxxxxxxxxxxx>
Cc: Brendan Gregg <brendan.d.gregg@xxxxxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: Eric Biederman <ebiederm@xxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Sargun Dhillon <sargun@xxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Link: http://lkml.kernel.org/r/148891931111.25309.11073854609798681633.stgit@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-record.c | 29 ++++++++++++--
tools/perf/util/event.c | 94 ++++++++++++++++++++++++++++++++++++++++++---
tools/perf/util/event.h | 6 +++
3 files changed, 119 insertions(+), 10 deletions(-)
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 99562c7242b6..04faef79a548 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -986,6 +986,7 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
*/
if (forks) {
union perf_event *event;
+ pid_t tgid;
event = malloc(sizeof(event->comm) + machine->id_hdr_size);
if (event == NULL) {
@@ -999,10 +1000,30 @@ static int __cmd_record(struct record *rec, int argc, const char **argv)
* cannot see a correct process name for those events.
* Synthesize COMM event to prevent it.
*/
- perf_event__synthesize_comm(tool, event,
- rec->evlist->workload.pid,
- process_synthesized_event,
- machine);
+ tgid = perf_event__synthesize_comm(tool, event,
+ rec->evlist->workload.pid,
+ process_synthesized_event,
+ machine);
+ free(event);
+
+ if (tgid == -1)
+ goto out_child;
+
+ event = malloc(sizeof(event->namespaces) +
+ (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
+ machine->id_hdr_size);
+ if (event == NULL) {
+ err = -ENOMEM;
+ goto out_child;
+ }
+
+ /*
+ * Synthesize NAMESPACES event for the command specified.
+ */
+ perf_event__synthesize_namespaces(tool, event,
+ rec->evlist->workload.pid,
+ tgid, process_synthesized_event,
+ machine);
free(event);
perf_evlist__start_workload(rec->evlist);
diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index fb52819023c7..d082cb70445d 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -221,6 +221,58 @@ pid_t perf_event__synthesize_comm(struct perf_tool *tool,
return tgid;
}
+static void perf_event__get_ns_link_info(pid_t pid, const char *ns,
+ struct perf_ns_link_info *ns_link_info)
+{
+ struct stat64 st;
+ char proc_ns[128];
+
+ sprintf(proc_ns, "/proc/%u/ns/%s", pid, ns);
+ if (stat64(proc_ns, &st) == 0) {
+ ns_link_info->dev = st.st_dev;
+ ns_link_info->ino = st.st_ino;
+ }
+}
+
+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)
+{
+ u32 idx;
+ struct perf_ns_link_info *ns_link_info;
+
+ if (!tool || !tool->namespace_events)
+ return 0;
+
+ memset(&event->namespaces, 0, (sizeof(event->namespaces) +
+ (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
+ machine->id_hdr_size));
+
+ event->namespaces.pid = tgid;
+ event->namespaces.tid = pid;
+
+ event->namespaces.nr_namespaces = NR_NAMESPACES;
+
+ ns_link_info = event->namespaces.link_info;
+
+ for (idx = 0; idx < event->namespaces.nr_namespaces; idx++)
+ perf_event__get_ns_link_info(pid, perf_ns__name(idx),
+ &ns_link_info[idx]);
+
+ event->namespaces.header.type = PERF_RECORD_NAMESPACES;
+
+ event->namespaces.header.size = (sizeof(event->namespaces) +
+ (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
+ machine->id_hdr_size);
+
+ if (perf_tool__process_synth_event(tool, event, machine, process) != 0)
+ return -1;
+
+ return 0;
+}
+
static int perf_event__synthesize_fork(struct perf_tool *tool,
union perf_event *event,
pid_t pid, pid_t tgid, pid_t ppid,
@@ -452,8 +504,9 @@ int perf_event__synthesize_modules(struct perf_tool *tool,
static int __event__synthesize_thread(union perf_event *comm_event,
union perf_event *mmap_event,
union perf_event *fork_event,
+ union perf_event *namespaces_event,
pid_t pid, int full,
- perf_event__handler_t process,
+ perf_event__handler_t process,
struct perf_tool *tool,
struct machine *machine,
bool mmap_data,
@@ -473,6 +526,11 @@ static int __event__synthesize_thread(union perf_event *comm_event,
if (tgid == -1)
return -1;
+ if (perf_event__synthesize_namespaces(tool, namespaces_event, pid,
+ tgid, process, machine) < 0)
+ return -1;
+
+
return perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
process, machine, mmap_data,
proc_map_timeout);
@@ -506,6 +564,11 @@ static int __event__synthesize_thread(union perf_event *comm_event,
if (perf_event__synthesize_fork(tool, fork_event, _pid, tgid,
ppid, process, machine) < 0)
break;
+
+ if (perf_event__synthesize_namespaces(tool, namespaces_event, _pid,
+ tgid, process, machine) < 0)
+ break;
+
/*
* Send the prepared comm event
*/
@@ -534,6 +597,7 @@ int perf_event__synthesize_thread_map(struct perf_tool *tool,
unsigned int proc_map_timeout)
{
union perf_event *comm_event, *mmap_event, *fork_event;
+ union perf_event *namespaces_event;
int err = -1, thread, j;
comm_event = malloc(sizeof(comm_event->comm) + machine->id_hdr_size);
@@ -548,10 +612,16 @@ int perf_event__synthesize_thread_map(struct perf_tool *tool,
if (fork_event == NULL)
goto out_free_mmap;
+ namespaces_event = malloc(sizeof(namespaces_event->namespaces) +
+ (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
+ machine->id_hdr_size);
+ if (namespaces_event == NULL)
+ goto out_free_fork;
+
err = 0;
for (thread = 0; thread < threads->nr; ++thread) {
if (__event__synthesize_thread(comm_event, mmap_event,
- fork_event,
+ fork_event, namespaces_event,
thread_map__pid(threads, thread), 0,
process, tool, machine,
mmap_data, proc_map_timeout)) {
@@ -577,7 +647,7 @@ int perf_event__synthesize_thread_map(struct perf_tool *tool,
/* if not, generate events for it */
if (need_leader &&
__event__synthesize_thread(comm_event, mmap_event,
- fork_event,
+ fork_event, namespaces_event,
comm_event->comm.pid, 0,
process, tool, machine,
mmap_data, proc_map_timeout)) {
@@ -586,6 +656,8 @@ int perf_event__synthesize_thread_map(struct perf_tool *tool,
}
}
}
+ free(namespaces_event);
+out_free_fork:
free(fork_event);
out_free_mmap:
free(mmap_event);
@@ -605,6 +677,7 @@ int perf_event__synthesize_threads(struct perf_tool *tool,
char proc_path[PATH_MAX];
struct dirent *dirent;
union perf_event *comm_event, *mmap_event, *fork_event;
+ union perf_event *namespaces_event;
int err = -1;
if (machine__is_default_guest(machine))
@@ -622,11 +695,17 @@ int perf_event__synthesize_threads(struct perf_tool *tool,
if (fork_event == NULL)
goto out_free_mmap;
+ namespaces_event = malloc(sizeof(namespaces_event->namespaces) +
+ (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
+ machine->id_hdr_size);
+ if (namespaces_event == NULL)
+ goto out_free_fork;
+
snprintf(proc_path, sizeof(proc_path), "%s/proc", machine->root_dir);
proc = opendir(proc_path);
if (proc == NULL)
- goto out_free_fork;
+ goto out_free_namespaces;
while ((dirent = readdir(proc)) != NULL) {
char *end;
@@ -638,13 +717,16 @@ int perf_event__synthesize_threads(struct perf_tool *tool,
* We may race with exiting thread, so don't stop just because
* one thread couldn't be synthesized.
*/
- __event__synthesize_thread(comm_event, mmap_event, fork_event, pid,
- 1, process, tool, machine, mmap_data,
+ __event__synthesize_thread(comm_event, mmap_event, fork_event,
+ namespaces_event, pid, 1, process,
+ tool, machine, mmap_data,
proc_map_timeout);
}
err = 0;
closedir(proc);
+out_free_namespaces:
+ free(namespaces_event);
out_free_fork:
free(fork_event);
out_free_mmap:
diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index b39ff795b9a9..e1d8166ebbd5 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -648,6 +648,12 @@ pid_t perf_event__synthesize_comm(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_mmap_events(struct perf_tool *tool,
union perf_event *event,
pid_t pid, pid_t tgid,
--
2.9.3