Re: [PATCH] add likely around access_ok for uaccess

[Pavel Machek]

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?
> 
> How much can it hurt?

The change is obviously okay, I just wanted to know... If it gains 30%
on sysv messages.. that would be pretty big surprise.
								Pavel
-- 
When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]
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