From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 3 May 2007 09:46:32 +0100 (BST) From: Hugh Dickins Subject: Re: 2.6.22 -mm merge plans: slub In-Reply-To: <20070503011515.0d89082b.akpm@linux-foundation.org> Message-ID: References: <20070430162007.ad46e153.akpm@linux-foundation.org> <20070501125559.9ab42896.akpm@linux-foundation.org> <20070503011515.0d89082b.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Christoph Lameter , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Thu, 3 May 2007, Andrew Morton wrote: > On Wed, 2 May 2007 10:25:47 -0700 (PDT) Christoph Lameter wrote: > > > +config ARCH_USES_SLAB_PAGE_STRUCT > > + bool > > + default y > > + depends on SPLIT_PTLOCK_CPUS <= NR_CPUS > > + > > That all seems to work as intended. > > However with NR_CPUS=8 SPLIT_PTLOCK_CPUS=4, enabling SLUB=y crashes the > machine early in boot. I thought that if that worked as intended, you wouldn't even get the chance to choose SLUB=y? That was how it was working for me (but I realize I didn't try more than make oldconfig). > > Too early for netconsole, no serial console. Wedges up uselessly with > CONFIG_XMON=n, does mysterious repeated uncontrollable exceptions with > CONFIG_XMON=y. This is all fairly typical for a powerpc/G5 crash :( > > However I was able to glimpse some stuff as it flew past. Crash started in > flush_old_exec and ended in pgtable_free_tlb -> kmem_cache_free. I don't know > how to do better than that I'm afraid, unless I'm to hunt down a PCIE serial > card, perhaps. That sounds like what happens when SLUB's pagestruct use meets SPLIT_PTLOCK's pagestruct use. Does your .config really show CONFIG_SLUB=y together with CONFIG_ARCH_USES_SLAB_PAGE_STRUCT=y? Hugh -- 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