Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758662AbaKUPHM (ORCPT ); Fri, 21 Nov 2014 10:07:12 -0500 Received: from mail-ig0-f181.google.com ([209.85.213.181]:53706 "EHLO mail-ig0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758554AbaKUPHJ (ORCPT ); Fri, 21 Nov 2014 10:07:09 -0500 From: Pranith Kumar To: Tejun Heo , Christoph Lameter , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v2 5/9] percpu: Replace smp_read_barrier_depends() with lockless_dereference() Date: Fri, 21 Nov 2014 10:05:59 -0500 Message-Id: <1416582363-20661-6-git-send-email-bobby.prani@gmail.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1416582363-20661-1-git-send-email-bobby.prani@gmail.com> References: <1416582363-20661-1-git-send-email-bobby.prani@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Recently lockless_dereference() was added which can be used in place of hard-coding smp_read_barrier_depends(). The following PATCH makes the change. Signed-off-by: Pranith Kumar --- include/linux/percpu-refcount.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/include/linux/percpu-refcount.h b/include/linux/percpu-refcount.h index 494ab05..3cf6759 100644 --- a/include/linux/percpu-refcount.h +++ b/include/linux/percpu-refcount.h @@ -128,10 +128,8 @@ static inline void percpu_ref_kill(struct percpu_ref *ref) static inline bool __ref_is_percpu(struct percpu_ref *ref, unsigned long __percpu **percpu_countp) { - unsigned long percpu_ptr = ACCESS_ONCE(ref->percpu_count_ptr); - /* paired with smp_store_release() in percpu_ref_reinit() */ - smp_read_barrier_depends(); + unsigned long percpu_ptr = lockless_dereference(ref->percpu_count_ptr); if (unlikely(percpu_ptr & __PERCPU_REF_ATOMIC)) return false; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/