Re: [lkp-robot] [locking/ww_mutex] 857811a371: INFO:task_blocked_for_more_than#seconds

[Chris Wilson]

On Wed, Mar 08, 2017 at 09:08:54AM +0800, kernel test robot wrote:
> 
> FYI, we noticed the following commit:
> 
> commit: 857811a37129f5d2ba162d7be3986eff44724014 ("locking/ww_mutex: Adjust the lock number for stress test")
> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
> 
> in testcase: boot
> 
> on test machine: qemu-system-i386 -enable-kvm -m 320M
> 
> caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):

Now the test is running, it takes too long. :)

wait_for_completion_interruptible() would stop the hung task check? That
leaves NMI watchdog to check if we hit a deadlock between the workers.

And add a timeout to the stress test.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre