perf stat: Remove use of die/exit and handle errors

Allows perf to clean up properly on program termination.

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1346005487-62961-5-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-stat.c

@@ -428,7 +428,7 @@ static int run_perf_stat(int argc __used, const char **argv)
 
 	if (forks && (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0)) {
 		perror("failed to create pipes");
-		exit(1);
+		return -1;
 	}
 
 	if (forks) {
@@ -510,7 +510,8 @@ static int run_perf_stat(int argc __used, const char **argv)
 			}
 			if (child_pid != -1)
 				kill(child_pid, SIGTERM);
-			die("Not all events could be opened.\n");
+
+			pr_err("Not all events could be opened.\n");
 			return -1;
 		}
 		counter->supported = true;
@@ -1189,7 +1190,7 @@ int cmd_stat(int argc, const char **argv, const char *prefix __used)
 		output = fopen(output_name, mode);
 		if (!output) {
 			perror("failed to create output file");
-			exit(-1);
+			return -1;
 		}
 		clock_gettime(CLOCK_REALTIME, &tm);
 		fprintf(output, "# started on %s\n", ctime(&tm.tv_sec));