From mboxrd@z Thu Jan 1 00:00:00 1970 From: Keir Fraser Date: Wed, 23 Nov 2005 15:37:07 +0000 Subject: Re: [Xen-devel] __ia64__ ifdef in xmalloc.c: "Fix ar.unat handling forfast paths" Message-Id: <883776988128f1657bc6dbd7d993cae1@cl.cam.ac.uk> List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: "Luck, Tony" Cc: "Tian, Kevin" , Xen Mailing List , linux-ia64@vger.kernel.org, Rusty Russell , Tony Breeds , djm@kirby.fc.hp.com, David Mosberger-Tang On 23 Nov 2005, at 15:07, Luck, Tony wrote: >> It's not hard to support arbitrary alignment, at the cost of burning >> some space. We should probably do that. > > The "we" in that last sentence is the Xen team ... referring > to making fixes to xmalloc? Correct. But I've thought more on it and I guess that actually the number of cases where we have structures with alignment requirements stricter than SMP_CACHE_BYTES will be very small. In fact I can't think of any in Xen right now. :-) So it makes most sense for ia64 Xen to define SMP_CACHE_BYTES to a sensible largeish number irrespective of CONFIG_SMP (after all, how many uniproc ia64 systems are there), and solve the general alignment problem in xmalloc only if we really need to. -- Keir