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Date: Tue, 30 Jun 2009 10:02:49 -0500
Message-ID: <ed82fe3e0906300802h2bcfb651q5f8a37423307e7ff@mail.gmail.com>
Subject: Re: [PATCH] powerpc: Fix spin_event_timeout() to be robust over
	context switches
From: Timur Tabi <timur@freescale.com>
To: Grant Likely <grant.likely@secretlab.ca>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>
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On Mon, Jun 29, 2009 at 6:40 PM, Grant Likely<grant.likely@secretlab.ca> wr=
ote:
> From: Grant Likely <grant.likely@secretlab.ca>
>
> Current implementation of spin_event_timeout can be interrupted by an
> IRQ or context switch after testing the condition, but before checking
> the timeout. =A0This can cause the loop to report a timeout when the
> condition actually became true in the middle.
>
> This patch adds one final check of the condition upon exit of the loop
> if the last test of the condition was still false.
>
> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

Acked-by: Timur Tabi <timur@freescale.com>

Ben, please pick this up for the next rc of 2.6.31.

--=20
Timur Tabi
Linux kernel developer at Freescale