linux-kernel - Re: [PATCH 1/2] ARM64:VDSO: Improve gettimeofday, don't use udiv

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Message-ID: <56F3FB80.50402@codeaurora.org>
Date:	Thu, 24 Mar 2016 10:36:48 -0400
From:	Christopher Covington <cov@...eaurora.org>
To:	Andrew Pinski <apinski@...ium.com>, pinskia@...il.com,
	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org
Cc:	Mark Rutland <Mark.Rutland@....com>,
	Ard Biesheuvel <ard.biesheuvel@...aro.org>
Subject: Re: [PATCH 1/2] ARM64:VDSO: Improve gettimeofday, don't use udiv

On 03/13/2016 03:50 PM, Andrew Pinski wrote:
> On many cores, udiv with a large value is slow, expand instead
> the division out to be what GCC would have generated for the
> divide by 1000.

This like checking object code into version control. Why not write in C
and let GCC perform the generation?

Thanks,
Cov

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