perf thread: Introduce method to set comm from /proc/pid/self

Will be used for lazy comm loading in 'perf trace'.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-7ogbkuoka1y2qsmcckqxvl5m@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2016-04-26 12:32:50 -03:00
parent 4bd112df3e
commit 2f3027ac28
2 changed files with 21 additions and 0 deletions

View File

@ -10,6 +10,8 @@
#include "comm.h" #include "comm.h"
#include "unwind.h" #include "unwind.h"
#include <api/fs/fs.h>
int thread__init_map_groups(struct thread *thread, struct machine *machine) int thread__init_map_groups(struct thread *thread, struct machine *machine)
{ {
struct thread *leader; struct thread *leader;
@ -153,6 +155,23 @@ int __thread__set_comm(struct thread *thread, const char *str, u64 timestamp,
return 0; return 0;
} }
int thread__set_comm_from_proc(struct thread *thread)
{
char path[64];
char *comm = NULL;
size_t sz;
int err = -1;
if (!(snprintf(path, sizeof(path), "%d/task/%d/comm",
thread->pid_, thread->tid) >= (int)sizeof(path)) &&
procfs__read_str(path, &comm, &sz) == 0) {
comm[sz - 1] = '\0';
err = thread__set_comm(thread, comm, 0);
}
return err;
}
const char *thread__comm_str(const struct thread *thread) const char *thread__comm_str(const struct thread *thread)
{ {
const struct comm *comm = thread__comm(thread); const struct comm *comm = thread__comm(thread);

View File

@ -71,6 +71,8 @@ static inline int thread__set_comm(struct thread *thread, const char *comm,
return __thread__set_comm(thread, comm, timestamp, false); return __thread__set_comm(thread, comm, timestamp, false);
} }
int thread__set_comm_from_proc(struct thread *thread);
int thread__comm_len(struct thread *thread); int thread__comm_len(struct thread *thread);
struct comm *thread__comm(const struct thread *thread); struct comm *thread__comm(const struct thread *thread);
struct comm *thread__exec_comm(const struct thread *thread); struct comm *thread__exec_comm(const struct thread *thread);