[PATCH] perf, tools: Stop perf stat -p when profiled process exits v3

[Andi Kleen <andi@firstfloor.org>]

From: Andi Kleen <ak@linux.intel.com>

When counting a process with perf stat -p check if the process died
and exit collection if yes.

v2: Add more checks, handle non -p again. Handle /proc not there.
v3: Handle multi pid case. Fix non /proc error path
Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
 tools/perf/builtin-stat.c |   14 +++++++++++++-
 1 files changed, 13 insertions(+), 1 deletions(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 861f0ae..b5e7df2 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -536,7 +536,19 @@ static int run_perf_stat(int argc __used, const char **argv)
 		if (WIFSIGNALED(status))
 			psignal(WTERMSIG(status), argv[0]);
 	} else {
-		while(!done) sleep(1);
+		char piddir[40];
+		int check_proc = target.pid &&
+				 access("/proc", X_OK) == 0 &&
+				 !strchr(target.pid, ',');
+		if (check_proc)
+			snprintf(piddir, sizeof piddir, "/proc/%d", 
+				 atoi(target.pid));
+		while(!done) {
+			sleep(1);
+			if (check_proc && access(piddir, X_OK) < 0 && 
+			    errno == ENOENT)
+				break;
+		}
 	}
 
 	t1 = rdclock();
-- 
1.7.7.6