Date: Thu, 26 Aug 2010 16:23:00 -0700 (PDT)
From: Davide Libenzi <davidel@xmailserver.org>
To: Thomas Gleixner <tglx@linutronix.de>
cc: Shawn Bohrer <shawn.bohrer@gmail.com>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        linux-fsdevel@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Arjan van de Ven <arjan@infradead.org>
Subject: Re: [PATCH] hrtimer: make epoll_wait() use the hrtimer range
 feature
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On Fri, 27 Aug 2010, Thomas Gleixner wrote:

> On Thu, 26 Aug 2010, Davide Libenzi wrote:
> > On Sun, 8 Aug 2010, Shawn Bohrer wrote:
> > 
> > > This make epoll use hrtimers for the timeout value which prevents
> > > epoll_wait() from timing out up to a millisecond early.
> > > 
> > > This mirrors the behavior of select() and poll().
> > 
> > I saw this now, since I got notifications from Andrew's patch machine.
> > Is this really needed?
> 
> Yes, as it is the last user space interface which is jiffies based.

What? You killed jiffies?! :)
Alright then, the patch itself, besides the different bahavior on timeout 
greater/equal to EP_MAX_MSTIMEO (which is not documented, hence does not 
exist), looks OK to me.


- Davide


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