Commit 18483b81 authored Dec 06, 2010 by Arnaldo Carvalho de Melo

perf record: Fix eternal wait for stillborn child



When execvp fails to find the specified command on the path we won't get
SIGCHLD, so send a SIGUSR1 and exit right away.

Current situation would require a SIGINT performed by the user and would
produce meaningless summary.

Now:

[acme@emilia linux]$ ./foo
-bash: ./foo: No such file or directory
[acme@emilia linux]$ perf record ./foo
./foo: No such file or directory
[acme@emilia linux]$

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 60e67737

tools/perf/builtin-record.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -197,7 +197,7 @@ static void sig_atexit(void)
		if (child_pid > 0)
		kill(child_pid, SIGTERM);

		if (signr == -1)
		if (signr == -1 \|\| signr == SIGUSR1)
		return;

		signal(signr, SIG_DFL);
		@@ -515,6 +515,7 @@ static int __cmd_record(int argc, const char **argv)
		atexit(sig_atexit);
		signal(SIGCHLD, sig_handler);
		signal(SIGINT, sig_handler);
		signal(SIGUSR1, sig_handler);

		if (forks && (pipe(child_ready_pipe) < 0 \|\| pipe(go_pipe) < 0)) {
		perror("failed to create pipes");
		@@ -606,6 +607,7 @@ static int __cmd_record(int argc, const char **argv)
		execvp(argv[0], (char **)argv);

		perror(argv[0]);
		kill(getppid(), SIGUSR1);
		exit(-1);
		}

		@@ -762,7 +764,7 @@ static int __cmd_record(int argc, const char **argv)
		}
		}

		if (quiet)
		if (quiet \|\| signr == SIGUSR1)
		return 0;

		fprintf(stderr, "[ perf record: Woken up %ld times to write data ]\n", waking);