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perf_counter: tools: Expand the COMM,MMAP event synthesizer
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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>
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Peter Zijlstra authored and Ingo Molnar committed Jun 2, 2009
1 parent 709e50c commit f70e87d
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Showing 2 changed files with 65 additions and 21 deletions.
84 changes: 64 additions & 20 deletions Documentation/perf_counter/builtin-record.c
Original file line number Diff line number Diff line change
Expand Up @@ -162,14 +162,16 @@ 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];
char bf[BUFSIZ];
int fd, ret;
size_t size;
char *field, *sep;
DIR *tasks;
struct dirent dirent, *next;

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

Expand All @@ -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;
Expand Down Expand Up @@ -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) {
Expand All @@ -274,15 +297,37 @@ 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;
int counter, group_fd;
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;
Expand Down Expand Up @@ -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);
Expand Down Expand Up @@ -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;
Expand Down
2 changes: 1 addition & 1 deletion Documentation/perf_counter/builtin-report.c
Original file line number Diff line number Diff line change
Expand Up @@ -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;

Expand Down

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