Subject: Re: [PATCH] task_work: add a scheduling point in task_work_run()
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Mimi Zohar <zohar@linux.vnet.ibm.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>,
        linux-security-module@vger.kernel.org,
        linux-kernel <linux-kernel@vger.kernel.org>,
        David Howells <dhowells@redhat.com>
In-Reply-To: <1345581470.2815.14.camel@falcor.watson.ibm.com>
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Date: Tue, 21 Aug 2012 23:32:05 +0200
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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.


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