From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932687Ab2J0TSg (ORCPT ); Sat, 27 Oct 2012 15:18:36 -0400 Received: from www.linutronix.de ([62.245.132.108]:38425 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932539Ab2J0TSf (ORCPT ); Sat, 27 Oct 2012 15:18:35 -0400 Date: Sat, 27 Oct 2012 21:18:30 +0200 (CEST) From: Thomas Gleixner To: Christoph Lameter cc: linux-mm@kvack.org, LKML Subject: [PATCH] slub: Use the correct per cpu slab on CPU_DEAD Message-ID: User-Agent: Alpine 2.02 (LFD 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org While making slub available for RT I noticed, that during CPU offline for each kmem_cache __flush_cpu_slab() is called on a live CPU. This correctly flushs the cpu_slab of the dead CPU via flush_slab. Though unfreeze_partials which is called from __flush_cpu_slab() after that looks at the cpu_slab of the cpu on which this is called. So we fail to look at the partials of the dead cpu. Correct this by extending the arguments of unfreeze_partials with the target cpu number and use per_cpu_ptr instead of this_cpu_ptr. Signed-off-by: Thomas Gleixner --- mm/slub.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) Index: linux-2.6/mm/slub.c =================================================================== --- linux-2.6.orig/mm/slub.c +++ linux-2.6/mm/slub.c @@ -1874,10 +1874,10 @@ redo: * * This function must be called with interrupt disabled. */ -static void unfreeze_partials(struct kmem_cache *s) +static void unfreeze_partials(struct kmem_cache *s, unsigned int cpu) { struct kmem_cache_node *n = NULL, *n2 = NULL; - struct kmem_cache_cpu *c = this_cpu_ptr(s->cpu_slab); + struct kmem_cache_cpu *c = per_cpu_ptr(s->cpu_slab, cpu); struct page *page, *discard_page = NULL; while ((page = c->partial)) { @@ -1963,7 +1963,7 @@ static int put_cpu_partial(struct kmem_c * set to the per node partial list. */ local_irq_save(flags); - unfreeze_partials(s); + unfreeze_partials(s, smp_processor_id()); local_irq_restore(flags); oldpage = NULL; pobjects = 0; @@ -2006,7 +2006,7 @@ static inline void __flush_cpu_slab(stru if (c->page) flush_slab(s, c); - unfreeze_partials(s); + unfreeze_partials(s, cpu); } }