From mboxrd@z Thu Jan 1 00:00:00 1970 Date: 14 Jan 2005 11:47:32 +0100 Date: Fri, 14 Jan 2005 11:47:32 +0100 From: Andi Kleen Subject: Re: page table lock patch V15 [0/7]: overview II Message-ID: <20050114104732.GB72915@muc.de> References: <41E5BC60.3090309@yahoo.com.au> <20050113031807.GA97340@muc.de> <20050113180205.GA17600@muc.de> <20050114043944.GB41559@muc.de> <1105678742.5402.109.camel@npiggin-nld.site> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1105678742.5402.109.camel@npiggin-nld.site> Sender: owner-linux-mm@kvack.org Return-Path: To: Nick Piggin Cc: clameter@sgi.com, Andrew Morton , torvalds@osdl.org, hugh@veritas.com, linux-mm@kvack.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, benh@kernel.crashing.org List-ID: > I have a question for the x86 gurus. We're currently using the lock > prefix for set_64bit. This will lock the bus for the RMW cycle, but > is it a prerequisite for the atomic 64-bit store? Even on UP? An atomic 64bit store doesn't need a lock prefix. A cmpxchg will need to though. Note that UP kernels define LOCK to nothing. -Andi -- 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/ . Don't email: aart@kvack.org