perf thrad_map: Add comm string into array
Adding support to hold comm name together with pids in 'struct
thread_map'. It will be useful for --per-thread option to display task
pid together with task name.
Adding thread_map__read_comms function that reads/set
comm string for the 'struct thread_map'.
Getting the task name from /proc/$pid/comm.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1435310967-14570-3-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/thread_map.c b/tools/perf/util/thread_map.c
index ed76c17..da7646d 100644
--- a/tools/perf/util/thread_map.c
+++ b/tools/perf/util/thread_map.c
@@ -8,9 +8,11 @@
#include <unistd.h>
#include "strlist.h"
#include <string.h>
+#include <api/fs/fs.h>
#include "asm/bug.h"
#include "thread_map.h"
#include "util.h"
+#include "debug.h"
/* Skip "." and ".." directories */
static int filter(const struct dirent *dir)
@@ -319,8 +321,12 @@
static void thread_map__delete(struct thread_map *threads)
{
if (threads) {
+ int i;
+
WARN_ONCE(atomic_read(&threads->refcnt) != 0,
"thread map refcnt unbalanced\n");
+ for (i = 0; i < threads->nr; i++)
+ free(thread_map__comm(threads, i));
free(threads);
}
}
@@ -348,3 +354,56 @@
return printed + fprintf(fp, "\n");
}
+
+static int get_comm(char **comm, pid_t pid)
+{
+ char *path;
+ size_t size;
+ int err;
+
+ if (asprintf(&path, "%s/%d/comm", procfs__mountpoint(), pid) == -1)
+ return -ENOMEM;
+
+ err = filename__read_str(path, comm, &size);
+ if (!err) {
+ /*
+ * We're reading 16 bytes, while filename__read_str
+ * allocates data per BUFSIZ bytes, so we can safely
+ * mark the end of the string.
+ */
+ (*comm)[size] = 0;
+ rtrim(*comm);
+ }
+
+ free(path);
+ return err;
+}
+
+static void comm_init(struct thread_map *map, int i)
+{
+ pid_t pid = thread_map__pid(map, i);
+ char *comm = NULL;
+
+ /* dummy pid comm initialization */
+ if (pid == -1) {
+ map->map[i].comm = strdup("dummy");
+ return;
+ }
+
+ /*
+ * The comm name is like extra bonus ;-),
+ * so just warn if we fail for any reason.
+ */
+ if (get_comm(&comm, pid))
+ pr_warning("Couldn't resolve comm name for pid %d\n", pid);
+
+ map->map[i].comm = comm;
+}
+
+void thread_map__read_comms(struct thread_map *threads)
+{
+ int i;
+
+ for (i = 0; i < threads->nr; ++i)
+ comm_init(threads, i);
+}