[PATCH v8 3/6] perf record: Synthesize namespace events for current processes
From: Hari Bathini
Date: Tue Mar 07 2017 - 15:42:47 EST
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.
Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Hari Bathini <hbathini@xxxxxxxxxxxxxxxxxx>
---
tools/perf/builtin-record.c | 29 ++++++++++-
tools/perf/util/event.c | 111 +++++++++++++++++++++++++++++++++++++++++--
tools/perf/util/event.h | 6 ++
3 files changed, 136 insertions(+), 10 deletions(-)
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 99562c7..04faef7 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 f118eac..5a99af8 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -50,6 +50,16 @@ static const char *perf_event__names[] = {
[PERF_RECORD_TIME_CONV] = "TIME_CONV",
};
+static const char *perf_ns__names[] = {
+ [NET_NS_INDEX] = "net",
+ [UTS_NS_INDEX] = "uts",
+ [IPC_NS_INDEX] = "ipc",
+ [PID_NS_INDEX] = "pid",
+ [USER_NS_INDEX] = "user",
+ [MNT_NS_INDEX] = "mnt",
+ [CGROUP_NS_INDEX] = "cgroup",
+};
+
const char *perf_event__name(unsigned int id)
{
if (id >= ARRAY_SIZE(perf_event__names))
@@ -59,6 +69,13 @@ const char *perf_event__name(unsigned int id)
return perf_event__names[id];
}
+static const char *perf_ns__name(unsigned int id)
+{
+ if (id >= ARRAY_SIZE(perf_ns__names))
+ return "UNKNOWN";
+ return perf_ns__names[id];
+}
+
static int perf_tool__process_synth_event(struct perf_tool *tool,
union perf_event *event,
struct machine *machine,
@@ -204,6 +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->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,
@@ -435,8 +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,
@@ -456,6 +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);
@@ -489,6 +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
*/
@@ -517,6 +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);
@@ -531,10 +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)) {
@@ -560,7 +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)) {
@@ -569,6 +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);
@@ -588,6 +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))
@@ -605,11 +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;
@@ -621,13 +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 26efc77..a46a1b4 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,