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Message-ID: <1386892059.15730.58.camel@pasglop>
Subject: Re: [PATCH v2 1/2] dcache: allow word-at-a-time name hashing with
 big-endian CPUs
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Will Deacon <will.deacon@arm.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 13 Dec 2013 10:47:39 +1100
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On Thu, 2013-12-12 at 10:38 -0800, Linus Torvalds wrote:
> Ok, looks good. So I'm taking these even though it's outside the merge
> window - they're small, and until you enable DCACHE_WORD_ACCESS on
> big-endian they don't actually do anything.
> 
> Ben - you might want to check if this makes DCACHE_WORD_ACCESS useful
> on PowerPC too. Right now that requires an efficient fls()
> implementation, but I think you have "cntlz" like ARM does.

Thanks. I'll see if I can get somebody to measure it. It should be good
though.

Cheers,
Ben.