From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753871Ab1AFUp6 (ORCPT ); Thu, 6 Jan 2011 15:45:58 -0500 Received: from smtp102.prem.mail.ac4.yahoo.com ([76.13.13.41]:36296 "HELO smtp102.prem.mail.ac4.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753235Ab1AFUp2 (ORCPT ); Thu, 6 Jan 2011 15:45:28 -0500 X-Yahoo-SMTP: _Dag8S.swBC1p4FJKLCXbs8NQzyse1SYSgnAbY0- X-YMail-OSG: oKIYsKEVM1l0paGr.zP0vz73.Yg.2QZTDWplGxgCSOLs901 7hDIwyzWM3bFds3rqdtZG.YsZ0VN71q2qqy8OQw9Jhb1ElJtxMMbPajL2Vqk zsLsyLUU1xFiDZPk4jNA3K5uDjoeWPlpuzXg_ppL5XOPcq39ItLjzAF3dxIm AGK6OowPjU3UBQTkN8q1sxZSb_4jMYi8c_nbTooqEgpcyA3oJKIHpNsQM3Wa M3RYIk8mkk9z5oGnVc_TzFeHlaz1j0VH_LCjisgj5nK2ZciCfjgPT92RuzXs od33ky3qFjBJmpJUsPYBmTtMaRWt8bJbhxcXdFOquiWbpnow- X-Yahoo-Newman-Property: ymail-3 Message-Id: <20110106204526.384256554@linux.com> User-Agent: quilt/0.48-1 Date: Thu, 06 Jan 2011 14:45:16 -0600 From: Christoph Lameter To: Tejun Heo Cc: akpm@linux-foundation.org Cc: Pekka Enberg Cc: linux-kernel@vger.kernel.org Cc: Eric Dumazet Cc: "H. Peter Anvin" Cc: Mathieu Desnoyers Subject: [cpuops cmpxchg double V2 3/4] slub: Get rid of slab_free_hook_irq() References: <20110106204513.669098445@linux.com> Content-Disposition: inline; filename=slub_remove_irq_freehook Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following patch will make the fastpaths lockless and will no longer require interrupts to be disabled. Calling the free hook with irq disabled will no longer be possible. Move the slab_free_hook_irq() logic into slab_free_hook. Only disable interrupts if the features are selected that require callbacks with interrupts off and reenable after calls have been made. Signed-off-by: Christoph Lameter --- mm/slub.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-) Index: linux-2.6/mm/slub.c =================================================================== --- linux-2.6.orig/mm/slub.c 2010-12-14 10:45:11.000000000 -0600 +++ linux-2.6/mm/slub.c 2010-12-14 10:46:40.000000000 -0600 @@ -805,14 +805,24 @@ static inline void slab_post_alloc_hook( static inline void slab_free_hook(struct kmem_cache *s, void *x) { kmemleak_free_recursive(x, s->flags); -} -static inline void slab_free_hook_irq(struct kmem_cache *s, void *object) -{ - kmemcheck_slab_free(s, object, s->objsize); - debug_check_no_locks_freed(object, s->objsize); - if (!(s->flags & SLAB_DEBUG_OBJECTS)) - debug_check_no_obj_freed(object, s->objsize); + /* + * Trouble is that we may no longer disable interupts in the fast path + * So in order to make the debug calls that expect irqs to be + * disabled we need to disable interrupts temporarily. + */ +#if defined(CONFIG_KMEMCHECK) || defined(CONFIG_LOCKDEP) + { + unsigned long flags; + + local_irq_save(flags); + kmemcheck_slab_free(s, x, s->objsize); + debug_check_no_locks_freed(x, s->objsize); + if (!(s->flags & SLAB_DEBUG_OBJECTS)) + debug_check_no_obj_freed(x, s->objsize); + local_irq_restore(flags); + } +#endif } /* @@ -1099,9 +1109,6 @@ static inline void slab_post_alloc_hook( static inline void slab_free_hook(struct kmem_cache *s, void *x) {} -static inline void slab_free_hook_irq(struct kmem_cache *s, - void *object) {} - #endif /* CONFIG_SLUB_DEBUG */ /* @@ -1893,8 +1900,6 @@ static __always_inline void slab_free(st local_irq_save(flags); c = __this_cpu_ptr(s->cpu_slab); - slab_free_hook_irq(s, x); - if (likely(page == c->page && c->node != NUMA_NO_NODE)) { set_freepointer(s, object, c->freelist); c->freelist = object;