Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753394AbbEMQeN (ORCPT ); Wed, 13 May 2015 12:34:13 -0400 Received: from mail-by2on0126.outbound.protection.outlook.com ([207.46.100.126]:54560 "EHLO na01-by2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752111AbbEMQeK (ORCPT ); Wed, 13 May 2015 12:34:10 -0400 Authentication-Results: freescale.com; dkim=none (message not signed) header.d=none; Message-ID: <1431534837.3868.42.camel@freescale.com> Subject: Re: [PATCH] powerpc/mpic: Remove WHOAMI readback after EOI From: Scott Wood To: Purcareata Bogdan CC: Bogdan Purcareata , , , , Date: Wed, 13 May 2015 11:33:57 -0500 In-Reply-To: <55534225.1050305@freescale.com> References: <1427193823-14597-1-git-send-email-bogdan.purcareata@freescale.com> <55534225.1050305@freescale.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.10-0ubuntu1~14.10.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Originating-IP: [2601:2:5800:3f7:12bf:48ff:fe84:c9a0] X-ClientProxiedBy: SN2PR10CA0010.namprd10.prod.outlook.com (25.160.12.148) To BLUPR03MB1476.namprd03.prod.outlook.com (25.163.81.18) X-Microsoft-Antispam: UriScan:;BCL:0;PCL:0;RULEID:;SRVR:BLUPR03MB1476; X-Microsoft-Antispam-PRVS: X-Exchange-Antispam-Report-Test: UriScan:; X-Exchange-Antispam-Report-CFA-Test: BCL:0;PCL:0;RULEID:(601004)(5005006)(3002001);SRVR:BLUPR03MB1476;BCL:0;PCL:0;RULEID:;SRVR:BLUPR03MB1476; X-Forefront-PRVS: 0575F81B58 X-Forefront-Antispam-Report: SFV:NSPM;SFS:(10019020)(6009001)(24454002)(51704005)(377424004)(110136002)(76176999)(47776003)(189998001)(33646002)(36756003)(50226001)(50466002)(46102003)(87976001)(92566002)(575784001)(86362001)(62966003)(2950100001)(77156002)(5001960100002)(50986999)(122386002)(5820100001)(19580405001)(40100003)(19580395003)(103116003)(15975445007)(23676002)(77096005)(42186005)(3826002)(4001450100001);DIR:OUT;SFP:1102;SCL:1;SRVR:BLUPR03MB1476;H:[IPv6:2601:2:5800:3f7:12bf:48ff:fe84:c9a0];FPR:;SPF:None;MLV:sfv;LANG:en; X-OriginatorOrg: freescale.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 May 2015 16:34:05.4853 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-Transport-CrossTenantHeadersStamped: BLUPR03MB1476 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1174 Lines: 33 On Wed, 2015-05-13 at 15:23 +0300, Purcareata Bogdan wrote: > Ping? > > On 24.03.2015 12:43, Bogdan Purcareata wrote: > > After previous discussions regarding the subject [1][2], there's no clear > > explanation or reason why the call was needed in the first place. The sensible > > argument is some sort of synchronization between the CPU and the MPIC, which > > hasn't been pointed out precisely and is no longer required (at least on BookE > > platforms). > > > > The benefit of this change is saving a MMIO trap per interrupt when running in a > > KVM guest. > > > > [1] https://patchwork.ozlabs.org/patch/429098/ > > [2] https://patchwork.ozlabs.org/patch/433557/ > > > > Signed-off-by: Bogdan Purcareata > > --- > > arch/powerpc/sysdev/mpic.c | 1 - > > 1 file changed, 1 deletion(-) Don't top-post. This is commit 56302c53d3dc477b8360954fc92c1dfc4fc0ec54 in Linus's tree. -Scott -- 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/