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Date: Wed, 7 May 2008 07:57:57 -0600
From: Matthew Wilcox <matthew@wil.cx>
To: Pavel Machek <pavel@suse.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>,
       pm list <linux-pm@lists.linux-foundation.org>,
       Ingo Molnar <mingo@elte.hu>, Len Brown <lenb@kernel.org>,
       LKML <linux-kernel@vger.kernel.org>, Matt Helsley <matthltc@us.ibm.com>,
       Cedric Le Goater <clg@fr.ibm.com>, Paul Menage <menage@google.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       Alan Stern <stern@rowland.harvard.edu>,
       Liam Howlett <howlett@gmail.com>
Subject: Re: [RFC][PATCH 2/2] Freezer: Try to handle killable tasks
Message-ID: <20080507135757.GT19219@parisc-linux.org>
References: <200805070003.56387.rjw@sisk.pl> <200805070007.56998.rjw@sisk.pl> <20080507094150.GG13858@elf.ucw.cz>
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On Wed, May 07, 2008 at 11:41:50AM +0200, Pavel Machek wrote:
> > @@ -182,6 +183,8 @@ __mutex_lock_common(struct mutex *lock, 
> >  		/* didnt get the lock, go to sleep: */
> >  		spin_unlock_mutex(&lock->wait_lock, flags);
> >  		schedule();
> > +		if (state == TASK_KILLABLE)
> > +			try_to_freeze();
> >  		spin_lock_mutex(&lock->wait_lock, flags);
> >  	}
> >  
> 
> I'm not comfortable with this one. Can the task be killable, but still
> hold some _other_ mutex? (and then release it only if it actually gets
> the signal?)

Yes, that's exactly what's supposed to happen.

-- 
Intel are signing my paycheques ... these opinions are still mine
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours.  We can't possibly take such
a retrograde step."