[U-Boot] [PATCH V2] arm: Use optimized memcpy and memset from linux

[Wolfgang Denk]

Dear =?ISO-8859-15?Q?Matthias_Wei=DFer?=,

In message <4D4018AD.7090001 at arcor.de> you wrote:
>
> > IIRC, the '---' line separates patch commit message (above) from
> > freeform comments and history (below). Here, at least the version
> > history should move below the '---' line.
> 
> Wolfgang asked me that I add the numbers to the commit message. For the 
> changelog I will investigate the git commands on how to do that best 
> without manually editing the patch file before git send-email them.

Indeed I find that these numbers are information that should go into
the commit message so this data is available to users who have to
decide whether they want to trade the increased speed for the
increased memory footprint.

> >> +- CONFIG_USE_ARCH_MEMCPY
> >> + CONFIG_USE_ARCH_MEMSET
> >> + If these options are used a optimized version of memcpy/memset will
> >> + be used if available. These functions may be faster under some
> >> + conditions but may increase the binary size.
> >> +
> >
> > The name of the options is not self-explaining to me. If the difference
> > is "generic vs arch-optimal", then maybe CONFIG_USE_ARCH_OPTIMAL_MEMxxx
> > would be a better name?
> 
> Wolfgang didn't object on these names. If we use the OPTIMAL form it is 
> still not clear what optimal mean. There may be a size optimized version 
> and a speed optimized version. So we would need 
> CONFIG_USE_ARCH_SPEED_OPTIMAL_MEMxxx which I personally dislike a lot as 
> it is quite long. I also think that if there is an architecture specific 
> function that it should be clear that this is optimal in some way.

Well, "optimal" is not a good idea as I am pretty sure that some
clever person will still be able to spare some cycles here and there,
so his code would be even "more optimal" ;-)

I think the names CONFIG_USE_ARCH_MEMCPY etc. are actually pretty
good, because they are in line with the standard names
__HAVE_ARCH_MEMCPY etc. that are used in a lot of libraries.

Best regards,

Wolfgang Denk

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