perf events: Change perf parameter --pid to process-wide collection instead of thread-wide

Parameter --pid (or -p) of perf currently means a thread-wide
collection. For exmaple, if a process whose id is 8888 has 10
threads, 'perf top -p 8888' just collects the main thread
statistics. That's misleading. Users are used to attach a whole
process when debugging a process by gdb. To follow normal usage
style, the patch change --pid to process-wide collection and add
--tid (-t) to mean a thread-wide collection.

Usage example is:

 # perf top -p 8888
 # perf record -p 8888 -f sleep 10
 # perf stat -p 8888 -f sleep 10

Above commands collect the statistics of all threads of process
8888.

Signed-off-by: Zhang Yanmin <yanmin_zhang@linux.intel.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Sheng Yang <sheng@linux.intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jes Sorensen <Jes.Sorensen@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: zhiteng.huang@intel.com
Cc: Zachary Amsden <zamsden@redhat.com>
LKML-Reference: <1268922965-14774-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Zhang, Yanmin 2010-03-18 11:36:05 -03:00 committed by Ingo Molnar
parent 46be604b5b
commit d6d901c23a
5 changed files with 366 additions and 187 deletions

View file

@ -7,6 +7,37 @@
#include "util.h"
#include "debug.h"
int find_all_tid(int pid, pid_t ** all_tid)
{
char name[256];
int items;
struct dirent **namelist = NULL;
int ret = 0;
int i;
sprintf(name, "/proc/%d/task", pid);
items = scandir(name, &namelist, NULL, NULL);
if (items <= 0)
return -ENOENT;
*all_tid = malloc(sizeof(pid_t) * items);
if (!*all_tid) {
ret = -ENOMEM;
goto failure;
}
for (i = 0; i < items; i++)
(*all_tid)[i] = atoi(namelist[i]->d_name);
ret = items;
failure:
for (i=0; i<items; i++)
free(namelist[i]);
free(namelist);
return ret;
}
void map_groups__init(struct map_groups *self)
{
int i;
@ -348,3 +379,4 @@ struct symbol *map_groups__find_symbol(struct map_groups *self,
return NULL;
}