Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755586AbbESMOa (ORCPT ); Tue, 19 May 2015 08:14:30 -0400 Received: from pandora.arm.linux.org.uk ([78.32.30.218]:56879 "EHLO pandora.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753961AbbESMO0 (ORCPT ); Tue, 19 May 2015 08:14:26 -0400 Date: Tue, 19 May 2015 13:13:49 +0100 From: Russell King - ARM Linux To: Sarbojit Ganguly Cc: Arnd Bergmann , "linux-arm-kernel@lists.infradead.org" , "Waiman.Long@hp.com" , "peterz@infradead.org" , "vikram.m@samsung.com" , "raghavendra.kt@linux.vnet.ibm.com" , "oleg@redhat.com" , "linux-kernel@vger.kernel.org" , "mingo@redhat.com" , SHARAN ALLUR , "hpa@zytor.com" , "tglx@linutronix.de" , "torvalds@linux-foundation.org" Subject: Re: [RFC] arm: Add for atomic half word exchange Message-ID: <20150519121349.GE2067@n2100.arm.linux.org.uk> References: <1795987946.405311432034410830.JavaMail.weblogic@ep2mlwas07a> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1795987946.405311432034410830.JavaMail.weblogic@ep2mlwas07a> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 938 Lines: 21 On Tue, May 19, 2015 at 11:20:11AM +0000, Sarbojit Ganguly wrote: > Yes, I will try to do that. OTOH, I saw that there was a discussion on > removal of bad_xchg() altogether. Perhaps that approach be better than > adding this half word exchange? The only possibility for removal of __bad_xchg() is to remove it's _definition_ only, not its callsite, so that we get a _link_ time error for use cases we don't support. Removing its callsite leaves us open to code malfunction: xchg() effectively becomes a no-op for sizes which are not supported, and that's a _very_ bad thing to happen. -- FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up according to speedtest.net. -- 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/