From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by mu-out-0910.google.com with SMTP id g7so280739muf for ; Wed, 06 Jun 2007 13:29:26 -0700 (PDT) Message-ID: <29495f1d0706061329o457d3c97q3a93c4ab2581a1c@mail.gmail.com> Date: Wed, 6 Jun 2007 13:29:25 -0700 From: "Nish Aravamudan" Subject: Re: SLUB: Use ilog2 instead of series of constant comparisons. In-Reply-To: <20070606131121.a8f7be78.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20070606100817.7af24b74.akpm@linux-foundation.org> <20070606131121.a8f7be78.akpm@linux-foundation.org> Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Christoph Lameter , linux-mm@kvack.org, Pekka Enberg , Andy Whitcroft , Martin Bligh List-ID: On 6/6/07, Andrew Morton wrote: > On Wed, 6 Jun 2007 11:36:07 -0700 (PDT) Christoph Lameter wrote: > > > On Wed, 6 Jun 2007, Andrew Morton wrote: > > > > > This caused test.kernel.org's power4 build to blow up: > > > > > > http://test.kernel.org/abat/93315/debug/test.log.0 > > > > > > fs/built-in.o(.text+0x148420): In function `.CalcNTLMv2_partial_mac_key': > > > : undefined reference to `.____ilog2_NaN' > > > > Hmmm... Weird message that does not allow too much analysis. > > The __ilog2_NaN comes about if 0 or a negative number is passed to ilog. > > There is no way for that to happen since we check for KMALLOC_MIN_SIZE > > and KMALLOC_MAX_SIZE in kmalloc_index() and an unsigned value is used. > > > > There is also nothing special in CalcNTLMv2_partial_mac_key(). Two > > kmallocs of 33 bytes and 132 bytes each. > > Yes, the code all looks OK. I suspect this is another case of the compiler > failing to remove unreachable stuff. > > > Buggy compiler (too much stress on constant folding)? Or hardware? Can we > > rerun the test? > > It happened multiple times: > http://test.kernel.org/functional/pSeries-101_2.html > > I'm sure there's a way of extracting the compiler version out of > test.kernel.org but I can't see it there. Andy, maybe we should toss a gcc > --version in there or something? I went and looked at one of the GOOD jobs and acc'g to that, the gcc is gcc version 3.3.3 (SuSE Linux) (http://test.kernel.org/abat/93029/summary) I agree, seems like it would be handy to spit that out somewhere nicer and easier to get to. Maybe the machine links at the top should point to a summary page which has a link to the .config, machine info, etc? (more indirection, but may be ok). Thanks, Nish -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org