Re: [patch] measurements, numbers about CONFIG_OPTIMIZE_INLINING=y impact

Matthew Wilcox
2009-01-09T17:39:14Z

On Fri, Jan 09, 2009 at 06:47:19PM +0100, Andi Kleen wrote:
> On Fri, Jan 09, 2009 at 10:28:01AM -0700, Matthew Wilcox wrote:
> > On Fri, Jan 09, 2009 at 06:20:11PM +0100, Andi Kleen wrote:
> > > Also cc Honza in case he has comments (you might want
> > > to review more of the thread in the archives)
> >
> > I think this particular bug is already known and discussed:
>
> I thought so initially too, but:
>
> >
> > http://gcc.gnu.org/ml/gcc/2008-12/msg00365.html
> >
> > and it hints at being fixed with gcc 4.4. Does anyone want to test
> > that?
>
> Hugh already tested with 4.4 and it didn't work well. At least
> a lot of the low level asm inlines were not inlined.
> So it looks like it's still mistuned for the kernel.

That seems like valuable feedback to give to the GCC developers.

Richi, you can find the whole thread at

http://marc.info/?l=linux-fsdevel&m=123150610901773&w=2

and http://marc.info/?l=linux-fsdevel&m=123150834405285&w=2 is also
relevant.

--
Matthew Wilcox Intel Open Source Technology Centre
"Bill, look, we understand that you're interested in selling us this
operating system, but compare it to ours. We can't possibly take such
a retrograde step."