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Subject: Re: [PATCH 6/8] i386: bitops: Don't mark memory as clobbered
	unnecessarily
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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Date: Wed, 25 Jul 2007 08:32:48 +1000
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On Tue, 2007-07-24 at 17:55 -0400, Trond Myklebust wrote:
> 
> If you want to use bitops as spinlocks you should rather be using
> <linux/bit_spinlock.h>. That also does the right thing w.r.t.
> pre-emption and sparse locking annotations.

Heh, I didn't know about those... A bit annoying that I can't override
them in the arch, I might be able to save a barrier or two here. Our
test_and_set_bit() contains both barriers for lock and unlock semantics
to cope with all kind of abuses, but your bit_spinlock obviously doesn't
need that.

Cheers,
Ben.