From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763599AbYHRTKp (ORCPT ); Mon, 18 Aug 2008 15:10:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762846AbYHRTFv (ORCPT ); Mon, 18 Aug 2008 15:05:51 -0400 Received: from ns1.suse.de ([195.135.220.2]:44282 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757236AbYHRTFu (ORCPT ); Mon, 18 Aug 2008 15:05:50 -0400 Date: Mon, 18 Aug 2008 11:45:28 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org, jejb@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Jan Beulich , Nick Piggin , Ingo Molnar Subject: [patch 52/60] x86: fix spin_is_contended() Message-ID: <20080818184528.GA29394@suse.de> References: <20080818183230.966310219@mini.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="x86-fix-spin_is_contended.patch" In-Reply-To: <20080818184035.GA29394@suse.de> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.26-stable review patch. If anyone has any objections, please let us know. ------------------ From: Jan Beulich commit 7bc069c6bc4ede519a7116be1b9e149a1dbf787a upstream The masked difference is what needs to be compared against 1, rather than the difference of masked values (which can be negative). Signed-off-by: Jan Beulich Acked-by: Nick Piggin Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- include/asm-x86/spinlock.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/include/asm-x86/spinlock.h +++ b/include/asm-x86/spinlock.h @@ -65,7 +65,7 @@ static inline int __raw_spin_is_contende { int tmp = ACCESS_ONCE(lock->slock); - return (((tmp >> 8) & 0xff) - (tmp & 0xff)) > 1; + return (((tmp >> 8) - tmp) & 0xff) > 1; } static __always_inline void __raw_spin_lock(raw_spinlock_t *lock) @@ -129,7 +129,7 @@ static inline int __raw_spin_is_contende { int tmp = ACCESS_ONCE(lock->slock); - return (((tmp >> 16) & 0xffff) - (tmp & 0xffff)) > 1; + return (((tmp >> 16) - tmp) & 0xffff) > 1; } static __always_inline void __raw_spin_lock(raw_spinlock_t *lock) --