Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753580AbaKRJ6A (ORCPT ); Tue, 18 Nov 2014 04:58:00 -0500 Received: from mx0.aculab.com ([213.249.233.131]:45925 "HELO mx0.aculab.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753066AbaKRJ54 (ORCPT ); Tue, 18 Nov 2014 04:57:56 -0500 From: David Laight To: "'Alexander Duyck'" , "linux-arch@vger.kernel.org" , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" CC: "mathieu.desnoyers@polymtl.ca" , "peterz@infradead.org" , "benh@kernel.crashing.org" , "heiko.carstens@de.ibm.com" , "mingo@kernel.org" , "mikey@neuling.org" , "linux@arm.linux.org.uk" , "donald.c.skidmore@intel.com" , "matthew.vick@intel.com" , "geert@linux-m68k.org" , "jeffrey.t.kirsher@intel.com" , "romieu@fr.zoreil.com" , "paulmck@linux.vnet.ibm.com" , "nic_swsd@realtek.com" , "will.deacon@arm.com" , "michael@ellerman.id.au" , "tony.luck@intel.com" , "torvalds@linux-foundation.org" , "oleg@redhat.com" , "schwidefsky@de.ibm.com" , "fweisbec@gmail.com" , "davem@davemloft.net" Subject: RE: [PATCH 0/4] Add lightweight memory barriers fast_rmb() and fast_wmb() Thread-Topic: [PATCH 0/4] Add lightweight memory barriers fast_rmb() and fast_wmb() Thread-Index: AQHQAorfzFQVR/NlWkyw/QBPbdjyr5xmJZCg Date: Tue, 18 Nov 2014 09:57:14 +0000 Message-ID: <063D6719AE5E284EB5DD2968C1650D6D1C9F2930@AcuExch.aculab.com> References: <20141117171005.22333.96544.stgit@ahduyck-server> In-Reply-To: <20141117171005.22333.96544.stgit@ahduyck-server> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.202.99.200] Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by nfs id sAI9w5Og019458 From: Alexander Duyck > These patches introduce two new primitives for synchronizing cache-enabled > memory writes and reads. These two new primitives are: > > fast_rmb() > fast_wmb() Not sure I like the names. If the aim is to sync data into the local cache so that hardware that is doing cache-snooping accesses sees the data then maybe local_rmb() and local_wmb() IIRC read_barrier_depends() is a nop on everything except alpha. Maybe add the default if it isn't defined by the MD file? David ????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m???? ????????I?