From: Matthew Garrett <mjg59@srcf.ucam.org>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
LKML <linux-kernel@vger.kernel.org>,
Arjan van de Ven <arjan@infradead.org>
Subject: Re: [PATCH] hrtimers: Special-case zero length sleeps
Date: Wed, 15 Feb 2012 14:58:58 +0000 [thread overview]
Message-ID: <20120215145857.GA21755@srcf.ucam.org> (raw)
In-Reply-To: <1329317650.2293.129.camel@twins>
Regardless of whether userspace should be concerning itself about this
kind of thing or not, there's plenty of userspace that calls sleep(0) on
the assumption that it'll get rescheduled. This makes using whole-system
timer slack difficult, because there are some applications that do this
even if they're event-driven and sleeping for significant lengths of
time here breaks them. I'd certainly understand the argument for fixing
userspace instead, but that's a massive task for something that's easily
special-cased in the kernel.
--
Matthew Garrett | mjg59@srcf.ucam.org
next prev parent reply other threads:[~2012-02-15 14:59 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-29 14:59 [PATCH] hrtimers: Special-case zero length sleeps Matthew Garrett
2012-02-15 14:40 ` Thomas Gleixner
2012-02-15 14:52 ` Matthew Garrett
2012-02-15 20:14 ` Thomas Gleixner
2012-02-15 20:22 ` Matthew Garrett
2012-02-15 20:30 ` Thomas Gleixner
2012-02-15 20:38 ` Matthew Garrett
2012-02-15 20:40 ` Peter Zijlstra
2012-02-15 20:43 ` Matthew Garrett
2012-02-15 20:46 ` Thomas Gleixner
2012-02-15 20:47 ` Matthew Garrett
2012-02-16 14:27 ` Matthew Garrett
2012-02-16 14:31 ` Alan Cox
2012-02-16 14:51 ` Peter Zijlstra
2012-02-16 15:01 ` Matthew Garrett
2012-02-16 19:09 ` Thomas Gleixner
2012-02-15 14:54 ` Peter Zijlstra
2012-02-15 14:58 ` Matthew Garrett [this message]
2012-02-15 20:22 ` Thomas Gleixner
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