lkml.org 
[lkml]   [2005]   [Feb]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] PPC/PPC64: Introduce CPU_HAS_FEATURE() macro

Hi,

> This is the patch to evaluate CPU_HAS_FEATURE() at compile time whenever
> possible. Testing showed that vmlinux shrinks around 4000 bytes with
> g5_defconfig. I also checked that pSeries code is completely unaltered
> semantically when support for all CPU types is enabled, although a few
> instructions are emitted in a different order by gcc.
>
> I have made cpu_has_feature() an inline function that expects the full
> name of a feature bit while the CPU_HAS_FEATURE() macro still behaves
> the same way as in Olofs original patch for now.

Interesting :) However we already get bug reports with the current
CONFIG_POWER4_ONLY option. I worry about adding more options that users
could get wrong unless there is a noticeable improvement in performance.

Anton
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:10    [W:0.095 / U:0.328 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site