Re: 2.5 'what to expect'

Brian Gerst (bgerst@didntduck.org)
Fri, 11 Jul 2003 13:51:53 -0400


Steven Cole wrote:
> On Fri, 2003-07-11 at 09:11, Larry McVoy wrote:
>
>>On Fri, Jul 11, 2003 at 04:00:33PM +0100, Alan Cox wrote:
>>
>>>On Gwe, 2003-07-11 at 15:46, Tomas Szepe wrote:
>>>
>>>>>>- gcc 3.2.2-5 as shipped by Red Hat generates incorrect code in the
>>>>>> kmalloc optimisation introduced in 2.5.71
>>>>>> See http://linus.bkbits.net:8080/linux-2.5/cset@1.1410
>>>>>
>>>>>This URL appears wrong!
>>>>
>>>>Nahh, that's just the same old annoying bkbits bug. Try with lynx...
>>>
>>>I did - it references a changeset unrelayed to kmalloc
>>
>>I know, sorry. The version numbers in BK are not stable, they can't be.
>>You have to use the underlying internal version number. If someone who
>>knows can show me the output of
>>
>> bk changes -r<correct rev>
>>
>>for that changeset I will figure out a way to have a URL that doesn't change
>>and send it to Dave for that doc as well as post it there.
>
>
> This looks like the right one as currently numbered.
>
> http://linus.bkbits.net:8080/linux-2.5/cset@1.1215.127.10
>
> Steven

There is no problem with the current version of this patch. I rewrote
the original patch to work around the bug in gcc. The bug is that:

if (size < X) return kmem_cache_alloc(...);

would not cause the remaining if statements to be marked as dead code, but:

if (size < X) goto found;
...
found: return kmem_cache_alloc(...);

does optimize properly.

--
				Brian Gerst

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