Re: [PATCH] add likely around access_ok for uaccess

From: Pavel Machek
Date: Tue Sep 16 2003 - 14:51:34 EST


Hi!

> while trying to figure out why sysv msg is around 30% slower than pipes
> for data transfers I noticed that gcc's autodetection (3.2.2) guesses
> the "if(access_ok())" tests in uaccess.h wrong and puts the error memset
> into the direct path and the copy out of line.
>
> The attached patch adds likely to the tests - any objections? What about
> the archs except i386?

How much speedup did you gain?
Pavel

--
When do you have a heart between your knees?
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