From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta12.messagelabs.com (mail6.bemta12.messagelabs.com [216.82.250.247]) by kanga.kvack.org (Postfix) with ESMTP id A35356B0011 for ; Thu, 26 May 2011 14:02:25 -0400 (EDT) Date: Thu, 26 May 2011 13:02:13 -0500 (CDT) From: Christoph Lameter Subject: Re: [slubllv5 07/25] x86: Add support for cmpxchg_double In-Reply-To: <1306432645.16757.137.camel@jaguar> Message-ID: References: <20110516202605.274023469@linux.com> <20110516202625.197639928@linux.com> <1306432645.16757.137.camel@jaguar> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Pekka Enberg Cc: David Rientjes , Eric Dumazet , "H. Peter Anvin" , linux-mm@kvack.org, Thomas Gleixner , tj@kernel.org On Thu, 26 May 2011, Pekka Enberg wrote: > On Mon, 2011-05-16 at 15:26 -0500, Christoph Lameter wrote: > > plain text document attachment (cmpxchg_double_x86) > > A simple implementation that only supports the word size and does not > > have a fallback mode (would require a spinlock). > > > > And 32 and 64 bit support for cmpxchg_double. cmpxchg double uses > > the cmpxchg8b or cmpxchg16b instruction on x86 processors to compare > > and swap 2 machine words. This allows lockless algorithms to move more > > context information through critical sections. > > > > Set a flag CONFIG_CMPXCHG_DOUBLE to signal the support of that feature > > during kernel builds. > > > > Signed-off-by: Christoph Lameter > > You forgot to CC Tejun for this patch. Ok. I can do that but the patch is not in the same context of the per cpu stuff that we worked on earlier. This is fully locked version of cmpxchg_double. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org