[tip:perfcounters/core] perf_counter: tools: Expand the COMM,MMAP event synthesizer

tip-bot for Peter Zijlstra
2009-06-02T14:20:16Z

Commit-ID: f70e87d7a6d9c5a23d5f43ed0a0c224c157ef597
Gitweb: http://git.kernel.org/tip/f70e87d7a6d9c5a23d5f43ed0a0c224c157ef597
Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
AuthorDate: Tue, 2 Jun 2009 14:13:24 +0200
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Tue, 2 Jun 2009 16:16:26 +0200

perf_counter: tools: Expand the COMM,MMAP event synthesizer

Include code to pre-construct mappings based on /proc,
on system wide recording.

Fix the existing code to properly fill out ->pid and ->tid.

The PID should be the Thread Group ID (PIDTYPE_PID of task->group_leader)
The TID should be the Thread ID (PIDTYPE_PID of task)

Furthermore, change the default sorting of report to comm,dso for a
better quick overview.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

---
Documentation/perf_counter/builtin-record.c | 84 ++++++++++++++++++++------
Documentation/perf_counter/builtin-report.c | 2 +-
2 files changed, 65 insertions(+), 21 deletions(-)

diff --git a/Documentation/perf_counter/builtin-record.c b/Documentation/perf_counter/builtin-record.c
index 9c151de..810fc27 100644
--- a/Documentation/perf_counter/builtin-record.c
+++ b/Documentation/perf_counter/builtin-record.c
@@ -162,7 +162,7 @@ struct comm_event {
char comm[16];
};

-static pid_t pid_synthesize_comm_event(pid_t pid)
+static void pid_synthesize_comm_event(pid_t pid, int full)
{
struct comm_event comm_ev;
char filename[PATH_MAX];
@@ -170,6 +170,8 @@ static pid_t pid_synthesize_comm_event(pid_t pid)
int fd, ret;
size_t size;
char *field, *sep;
+ DIR *tasks;
+ struct dirent dirent, *next;

snprintf(filename, sizeof(filename), "/proc/%d/stat", pid);

@@ -194,29 +196,50 @@ static pid_t pid_synthesize_comm_event(pid_t pid)
goto out_failure;
size = sep - field;
memcpy(comm_ev.comm, field, size++);
- field = strchr(sep + 4, ' ');
- if (field == NULL)
- goto out_failure;
- comm_ev.pid = atoi(++field);
+
+ comm_ev.pid = pid;
comm_ev.header.type = PERF_EVENT_COMM;
- comm_ev.tid = pid;
size = ALIGN(size, sizeof(uint64_t));
comm_ev.header.size = sizeof(comm_ev) - (sizeof(comm_ev.comm) - size);

- ret = write(output, &comm_ev, comm_ev.header.size);
- if (ret < 0) {
- perror("failed to write");
- exit(-1);
+ if (!full) {
+ comm_ev.tid = pid;
+
+ ret = write(output, &comm_ev, comm_ev.header.size);
+ if (ret < 0) {
+ perror("failed to write");
+ exit(-1);
+ }
+ return;
+ }
+
+ snprintf(filename, sizeof(filename), "/proc/%d/task", pid);
+
+ tasks = opendir(filename);
+ while (!readdir_r(tasks, &dirent, &next) && next) {
+ char *end;
+ pid = strtol(dirent.d_name, &end, 10);
+ if (*end)
+ continue;
+
+ comm_ev.tid = pid;
+
+ ret = write(output, &comm_ev, comm_ev.header.size);
+ if (ret < 0) {
+ perror("failed to write");
+ exit(-1);
+ }
}
- return comm_ev.pid;
+ closedir(tasks);
+ return;
+
out_failure:
fprintf(stderr, "couldn't get COMM and pgid, malformed %s\n",
filename);
exit(EXIT_FAILURE);
- return -1;
}

-static void pid_synthesize_mmap_events(pid_t pid, pid_t pgid)
+static void pid_synthesize_mmap_events(pid_t pid)
{
char filename[PATH_MAX];
FILE *fp;
@@ -261,7 +284,7 @@ static void pid_synthesize_mmap_events(pid_t pid, pid_t pgid)
mmap_ev.len -= mmap_ev.start;
mmap_ev.header.size = (sizeof(mmap_ev) -
(sizeof(mmap_ev.filename) - size));
- mmap_ev.pid = pgid;
+ mmap_ev.pid = pid;
mmap_ev.tid = pid;

if (write(output, &mmap_ev, mmap_ev.header.size) < 0) {
@@ -274,6 +297,28 @@ static void pid_synthesize_mmap_events(pid_t pid, pid_t pgid)
fclose(fp);
}

+static void synthesize_events(void)
+{
+ DIR *proc;
+ struct dirent dirent, *next;
+
+ proc = opendir("/proc");
+
+ while (!readdir_r(proc, &dirent, &next) && next) {
+ char *end;
+ pid_t pid;
+
+ pid = strtol(dirent.d_name, &end, 10);
+ if (*end) /* only interested in proper numerical dirents */
+ continue;
+
+ pid_synthesize_comm_event(pid, 1);
+ pid_synthesize_mmap_events(pid);
+ }
+
+ closedir(proc);
+}
+
static void open_counters(int cpu, pid_t pid)
{
struct perf_counter_hw_event hw_event;
@@ -281,8 +326,8 @@ static void open_counters(int cpu, pid_t pid)
int track = 1;

if (pid > 0) {
- pid_t pgid = pid_synthesize_comm_event(pid);
- pid_synthesize_mmap_events(pid, pgid);
+ pid_synthesize_comm_event(pid, 0);
+ pid_synthesize_mmap_events(pid);
}

group_fd = -1;
@@ -348,7 +393,7 @@ static int __cmd_record(int argc, const char **argv)
assert(nr_cpus <= MAX_NR_CPUS);
assert(nr_cpus >= 0);

- output = open(output_name, O_CREAT|O_EXCL|O_RDWR, S_IRWXU);
+ output = open(output_name, O_CREAT|O_EXCL|O_TRUNC|O_RDWR, S_IRUSR|S_IWUSR);
if (output < 0) {
perror("failed to create output file");
exit(-1);
@@ -385,9 +430,8 @@ static int __cmd_record(int argc, const char **argv)
}
}

- /*
- * TODO: store the current /proc/$/maps information somewhere
- */
+ if (system_wide)
+ synthesize_events();

while (!done) {
int hits = events;
diff --git a/Documentation/perf_counter/builtin-report.c b/Documentation/perf_counter/builtin-report.c
index 20a4e51..0558c1e 100644
--- a/Documentation/perf_counter/builtin-report.c
+++ b/Documentation/perf_counter/builtin-report.c
@@ -18,7 +18,7 @@

static char const *input_name = "perf.data";
static char *vmlinux = NULL;
-static char *sort_order = "pid,symbol";
+static char *sort_order = "comm,dso";
static int input;
static int show_mask = SHOW_KERNEL | SHOW_USER | SHOW_HV;