From mboxrd@z Thu Jan 1 00:00:00 1970 From: Akira Hayakawa Subject: Re: [dm-devel] dm-writeboost testing Date: Sun, 06 Oct 2013 11:14:50 +0900 Message-ID: <5250C79A.8060103@gmail.com> References: <524E27DD.2050809@gmail.com> <524ECFC9.3000603@gmail.com> <524FBA3F.3050409@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: mpatocka@redhat.com Cc: dm-devel@redhat.com, devel@driverdev.osuosl.org, thornber@redhat.com, snitzer@redhat.com, cesarb@cesarb.net, gregkh@linuxfoundation.org, david@fromorbit.com, linux-kernel@vger.kernel.org, tj@kernel.org, agk@redhat.com, joe@perches.com, akpm@linux-foundation.org, ejt@redhat.com, dan.carpenter@oracle.com, m.chehab@samsung.com, ruby.wktk@gmail.com List-Id: dm-devel.ids Mikulas, > The change seems ok. Please, also move this piece of code in flush_proc > out of the spinlock: > if (kthread_should_stop()) > return 0; > > It caused the workqueue warning I reported before and still causes warning > with kthreads: > note: flush_daemon[5145] exited with preempt_count 1 You are right. I fixed the bug. diff --git a/Driver/dm-writeboost-daemon.c b/Driver/dm-writeboost-daemon.c index 65974e2..cf790bf 100644 --- a/Driver/dm-writeboost-daemon.c +++ b/Driver/dm-writeboost-daemon.c @@ -29,7 +29,6 @@ int flush_proc(void *data) cache->flush_wait_queue, (!list_empty(&cache->flush_queue)), msecs_to_jiffies(100)); - spin_lock_irqsave(&cache->flush_queue_lock, flags); /* * flush daemon can exit @@ -37,6 +36,8 @@ int flush_proc(void *data) */ if (kthread_should_stop()) return 0; + else + spin_lock_irqsave(&cache->flush_queue_lock, flags); } > I will send you next email with more bugs that I found in your code I will reply to you about this later. So much bugs and some seems to be crucial. Akira