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From: Oleg Nesterov <oleg@redhat.com>
To: naresh kamboju <naresh.kernel@gmail.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>,
	Roland McGrath <roland@redhat.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Christoph Hellwig <hch@infradead.org>,
	Ingo Molnar <mingo@elte.hu>, Pavel Emelyanov <xemul@openvz.org>,
	linux-kernel@vger.kernel.org
Subject: open_posix_testsuite: STOP + CONT + wait hang?
Date: Sat, 6 Jun 2009 08:47:49 +0200	[thread overview]
Message-ID: <20090606064749.GA13508@redhat.com> (raw)
In-Reply-To: <f5a7b3810906050843g6cbf5067o5ba1b9e07e5e2f5b@mail.gmail.com>

(change the subject)

On 06/05, naresh kamboju wrote:
>
> I want to inform 2.6.29 signal issues,
> As per my understanding I have noticed that if there is a delay
> (sleep/nanosleep/usleep) in the child process. Child could not
> reporting exit status to parent at this situation parent is waiting
> for ever by combinations of SIGSTOP and SIGCONT. So test cases are
> reporting as HUNG.

Thanks for report, but please provide more info.

> ARCH: ARM

is it ARM specific? I can't reproduce the problem on x86.

> KERNEL: 2.6.29.1

did you try other kernel versions?

> #define SLEEPSEC 5
...
> 	if ((pid = fork()) == 0) {
> 		/* child here */
> 		struct timespec tssleep;
>
> 		tssleep.tv_sec=SLEEPSEC;
> 		tssleep.tv_nsec=0;
> 		if (clock_nanosleep(CLOCK_REALTIME, 0, &tssleep, NULL) == 0) {
> 			printf("clock_nanosleep() returned success\n");
> 			return CHILDPASS;
> 		} else {
> 			printf("clock_nanosleep() did not return success\n");
> 			return CHILDFAIL;
> 		}
> 		return CHILDFAIL;
> 	} else {
> 		/* parent here */
> 		int i;
>
> 		sleep(1);
>
> 		if (kill(pid, SIGSTOP) != 0) {
> 			printf("Could not raise SIGSTOP\n");
> 			return PTS_UNRESOLVED;
> 		}
>
> 		if (kill(pid, SIGCONT) != 0) {
> 			printf("Could not raise SIGCONT\n");
> 			return PTS_UNRESOLVED;
> 		}
>
> 		if (wait(&i) == -1) {

And I guess it hangs here, right?

The child should sleep SLEEPSEC seconds then exit, so the whole
test-case should take SLEEPSEC seconds too.


Do you mean it really hangs and never completes?

Can you confirm it hangs in wait() ?

Does the child print "returned success" ?

If you can reproduce the problem, please send the content of
/proc/CHILD_PID/status and /proc/PARENT_PID/status.

Oleg.


  parent reply	other threads:[~2009-06-06  6:52 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-05-25 18:55 [PATCH 1/1] ptrace: do_notify_parent_cldstop: fix the wrong ->nsproxy usage Oleg Nesterov
2009-05-25 19:39 ` Oleg Nesterov
2009-05-27  1:06   ` Roland McGrath
2009-05-27 23:24     ` Oleg Nesterov
2009-05-26 21:05 ` Roland McGrath
2009-05-26 21:33   ` Oleg Nesterov
2009-05-27  0:55     ` Roland McGrath
2009-06-02  4:54       ` Sukadev Bhattiprolu
2009-06-05 15:43         ` naresh kamboju
2009-06-06  0:19           ` Roland McGrath
2009-06-06  6:47           ` Oleg Nesterov [this message]
2009-06-17  8:35             ` open_posix_testsuite: STOP + CONT + wait hang? naresh kamboju
2009-06-17 13:29               ` Oleg Nesterov
2009-06-17 14:34                 ` naresh kamboju
2009-05-27 21:32   ` [PATCH 1/1] ptrace: do_notify_parent_cldstop: fix the wrong ->nsproxy usage Oleg Nesterov
2009-05-27 22:23     ` Roland McGrath
2009-05-27 23:12       ` Oleg Nesterov
2009-05-27 23:26         ` Roland McGrath
2009-05-27 23:43           ` Oleg Nesterov
2009-05-27 23:51             ` Roland McGrath
2009-05-28  0:05               ` Oleg Nesterov
2009-06-02  4:48 ` Sukadev Bhattiprolu

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