From: Matthew Garrett <mjg59@srcf.ucam.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>,
Arjan van de Ven <arjan@infradead.org>,
Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH] hrtimers: Special-case zero length sleeps
Date: Thu, 16 Feb 2012 14:27:33 +0000 [thread overview]
Message-ID: <20120216142733.GA15632@srcf.ucam.org> (raw)
In-Reply-To: <20120215204757.GA30275@srcf.ucam.org>
On Wed, Feb 15, 2012 at 08:47:57PM +0000, Matthew Garrett wrote:
> Ok. I'll work on finding how prevelant it is and see if we can kill it
> off in userspace.
Checking through an exploded Fedora kernel tree suggests around 125
packages out of 11000 or so, so around 1% of userspace seems to use
sleep(0) under certain circumstances. We can probably fix everything in
the distribution, but that suggests that there's also going to be a
significant amount of code in the outside world that's also broken.
Userspace clearly has an expectation that sleep(0) is magic in some
ill-defined way. We'd be well within our rights to break that
expectation, but I think it's common enough to warrant special casing.
--
Matthew Garrett | mjg59@srcf.ucam.org
next prev parent reply other threads:[~2012-02-16 14:27 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 [this message]
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
2012-02-15 20:22 ` Thomas Gleixner
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