Re: [2.6.7-rc1-mm1] lp int copy_to_user replaced

[Andrew Morton]

FabF <fabian.frederick@xxxxxxxxx> wrote:
>
>  On Thu, 2004-05-27 at 20:01, viro@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
>  wrote:
>  > On Thu, May 27, 2004 at 07:32:08PM +0200, FabF wrote:
>  > > Andrew,
>  > > 
>  > > 	Here's a patch to have standard __put_user for integer transfers in lp
>  > > driver.Is it correct ?
>  > 
>  > What the hell for?  copy_to_user()/copy_from_user() is perfectly OK here.
>  > 
>  And why the hell use generic functions when we have neat small type
>  exchange macros ?

copy_*_user() has special-case code to handle 1, 2 and 4-byte copies, so
your patch should make no difference on x86.  Other architectures do not
have that optimisation.

So the patch is a tiny optimisation for some architectures.  However, it's
of very small benefit - we could make a million such changes.  Would prefer
more substantial things at this time, please.
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