From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nick Piggin Date: Tue, 12 Sep 2006 00:35:19 +0000 Subject: Re: [PATCH 3/6] Optional ZONE_DMA in the VM Message-Id: <450600C7.7090801@yahoo.com.au> List-Id: References: <20060911222744.4849.26386.sendpatchset@schroedinger.engr.sgi.com> In-Reply-To: <20060911222744.4849.26386.sendpatchset@schroedinger.engr.sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Christoph Lameter wrote: > Make ZONE_DMA optional in core code. > > - ifdef definitions for ZONE_DMA and related code following > the example for ZONE_DMA32 and ZONE_HIGHMEM. > > - Without ZONE_DMA, ZONE_HIGHMEM and ZONE_DMA32 we get to a > ZONES_SHIFT of 0. > > - Modify the VM statistics to work correctly without a DMA > zone. > > - Modify slab to not create DMA slabs if there is no > ZONE_DMA. > > Signed-off-by: Christoph Lameter Nice. Looks like it should remove a bit of overhead. I can't see from your patches, but what happens if someone asks for a GFP_DMA page or dma slab allocation when there is no ZONE_DMA? -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com