From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Martin J. Bligh" Date: Thu, 26 Feb 2004 22:21:02 +0000 Subject: Re: [Lse-tech] Re: fix zonelist ordering for NUMA Message-Id: <100070000.1077834062@flay> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org --On Wednesday, February 25, 2004 08:54:09 -0800 Jesse Barnes wrote: > On Wed, Feb 25, 2004 at 02:01:16PM +0900, j-nomura@ce.jp.nec.com wrote: >> > 1) make it arch independent >> > this means having arch code populate a SLIT-like table for use by >> > the generic zonelist building code >> >> I would like to hear the comments from people on other arch. >> If the same ordering rule can be applicable for others, it's nice. > > Martin, does a scheme like this sound ok with you? Arch specific code > would populate a node distance table, which would be used to build each > pgdat->zonelist in a smarter way than we do currently. Yeah, looks sensible to me. We probably ought to do this: +#ifndef node_distance +#define node_distance(from,to) (1) +#endif in the generic fallback topology headers, not in the mm/ .c files. Matt? Also, I seem to recall those build_zonelists functions are used for both NUMA and UMA ... now they're getting complex enough that it's probably worth making a specific non-NUMA version, if only for the sanity of 99% of the poor souls trying to work out how a UMA machine lays it out ;-) It looks like it won't change ordering for existing boxes with single layer flat NUMA topologies (round-robin), but we probably ought to check that carefully ;-) M.