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Message-ID: <1345605221.2366.2.camel@falcor.watson.ibm.com>
Subject: Re: [PATCH] task_work: add a scheduling point in task_work_run()
From: Mimi Zohar <zohar@linux.vnet.ibm.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>, Oleg Nesterov <oleg@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        ". James Morris" <jmorris@namei.org>,
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        linux-kernel <linux-kernel@vger.kernel.org>,
        David Howells <dhowells@redhat.com>
Date: Tue, 21 Aug 2012 23:13:41 -0400
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On Tue, 2012-08-21 at 23:32 +0200, Eric Dumazet wrote:
> On Tue, 2012-08-21 at 16:37 -0400, Mimi Zohar wrote:
> 
> > We're here, because fput() called schedule_work() to delay the last
> > fput().  The execution needs to take place before the syscall returns to
> > userspace.  Need to read __schedule()...  Do you know if cond_resched()
> > can guarantee that it will be executed before the return to userspace? 
> 
> Some clarifications : 
> 
> - fput() does not call schedule_work() in this case but task_work_add()
> 
> - cond_resched() wont return to userspace.

Thanks for the clarification.

Mimi