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Subject: RE: [PATCH 0/24] make atomic_read() behave consistently across all architectures
Date: Thu, 16 Aug 2007 14:08:52 -0700
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Thread-Topic: [PATCH 0/24] make atomic_read() behave consistently across all architectures
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From: "Luck, Tony" <tony.luck@intel.com>
To: "Chris Snook" <csnook@redhat.com>,
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>> 6674:   while (atomic_read(&j->DSPWrite) > 0)
>> 6675-           atomic_dec(&j->DSPWrite);
>
> If the maintainer of this code doesn't see a compelling reason to add 
> cpu_relax() in this loop, then it should be patched.

Shouldn't it be just re-written without the loop:

	if ((tmp = atomic_read(&j->DSPWrite)) > 0)
		atomic_sub(&j->DSPWrite, tmp);

Has all the same bugs, but runs much faster :-)

-Tony
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