Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit e907caf3 authored by Hari Bathini's avatar Hari Bathini Committed by Arnaldo Carvalho de Melo
Browse files

perf record: Synthesize namespace events for current processes 



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: default avatarHari Bathini <hbathini@linux.vnet.ibm.com>
Tested-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Aravinda Prasad <aravinda@linux.vnet.ibm.com>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/148891931111.25309.11073854609798681633.stgit@hbathini.in.ibm.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent f3b3614a

tools/perf/builtin-record.c

+25 −4
Original line number Diff line number Diff line
@@ -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) {
@@ -999,12 +1000,32 @@ 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,

		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);

	}

tools/perf/util/event.c

+88 −6
Original line number Diff line number Diff line
@@ -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,
@@ -452,6 +504,7 @@ 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,

				      struct perf_tool *tool,
@@ -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:

tools/perf/util/event.h

+6 −0
Original line number Diff line number Diff line
@@ -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,