From: Thomas Gleixner <tglx@linutronix.de>
To: Davide Libenzi <davidel@xmailserver.org>
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
Date: Fri, 27 Aug 2010 01:02:09 +0200 (CEST) [thread overview]
Message-ID: <alpine.LFD.2.00.1008270059240.2768@localhost.localdomain> (raw)
In-Reply-To: <alpine.DEB.2.00.1008261543470.25446@makko.or.mcafeemobile.com>
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.
> Is that really worth the extra code in the fast path?
It's not that much overhead and we had no complaints when we converted
everything else
> Aren't we breaking existing behavior?
We had no problems when we moved all the other interfaces over
> I have some doubts.
/me not - though I need to look at the patch itself
Thanks,
tglx
next prev parent reply other threads:[~2010-08-26 23:02 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-08-08 22:45 Shawn Bohrer
2010-08-26 22:31 ` Andrew Morton
2010-08-26 22:45 ` Davide Libenzi
2010-08-26 23:02 ` Thomas Gleixner [this message]
2010-08-26 23:23 ` Davide Libenzi
2010-11-24 8:33 ` Mike Frysinger
2010-11-24 14:52 ` Shawn Bohrer
2010-11-24 20:57 ` Mike Frysinger
2010-11-25 3:31 ` [PATCH] epoll: initialize slack for negative timeout values Shawn Bohrer
2010-11-27 18:58 ` Davide Libenzi
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=alpine.LFD.2.00.1008270059240.2768@localhost.localdomain \
--to=tglx@linutronix.de \
--cc=arjan@infradead.org \
--cc=davidel@xmailserver.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=shawn.bohrer@gmail.com \
--cc=viro@zeniv.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®