From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C495FC4742C for ; Mon, 16 Nov 2020 18:49:24 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3722B2224B for ; Mon, 16 Nov 2020 18:49:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3722B2224B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 180886B0036; Mon, 16 Nov 2020 13:49:23 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 1304E6B005C; Mon, 16 Nov 2020 13:49:23 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 01E906B005D; Mon, 16 Nov 2020 13:49:22 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0222.hostedemail.com [216.40.44.222]) by kanga.kvack.org (Postfix) with ESMTP id C8DCC6B0036 for ; Mon, 16 Nov 2020 13:49:22 -0500 (EST) Received: from smtpin17.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 69A3A3624 for ; Mon, 16 Nov 2020 18:49:22 +0000 (UTC) X-FDA: 77491169364.17.song95_010a9332732b Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin17.hostedemail.com (Postfix) with ESMTP id 4FD25180D0180 for ; Mon, 16 Nov 2020 18:49:22 +0000 (UTC) X-HE-Tag: song95_010a9332732b X-Filterd-Recvd-Size: 3669 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by imf34.hostedemail.com (Postfix) with ESMTP for ; Mon, 16 Nov 2020 18:49:21 +0000 (UTC) IronPort-SDR: pXFePC9mtxo4xMBPsAxaf/7tMbvccf0QXIlgjcVUI3S54k4LBrefPZIGtJbYx/o0/lbbn8TCva GBORYc4uD0OQ== X-IronPort-AV: E=McAfee;i="6000,8403,9807"; a="168220236" X-IronPort-AV: E=Sophos;i="5.77,483,1596524400"; d="scan'208";a="168220236" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Nov 2020 10:49:18 -0800 IronPort-SDR: QM3K1Df9J/Wg+oJAcVfa83qY/TNr4BOrYcj8zI8YrrZ97jsEsonZ8J/uK1N6DUXothgxIsiUVW Pzs792lhR6LA== X-IronPort-AV: E=Sophos;i="5.77,483,1596524400"; d="scan'208";a="533514829" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Nov 2020 10:49:17 -0800 Date: Mon, 16 Nov 2020 10:49:16 -0800 From: Ira Weiny To: Thomas Gleixner Cc: Ingo Molnar , Borislav Petkov , Andy Lutomirski , Peter Zijlstra , Dave Hansen , x86@kernel.org, linux-kernel@vger.kernel.org, Andrew Morton , Fenghua Yu , linux-doc@vger.kernel.org, linux-nvdimm@lists.01.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, Dan Williams , Greg KH Subject: Re: [PATCH V3 05/10] x86/entry: Pass irqentry_state_t by reference Message-ID: <20201116184916.GA722447@iweiny-DESK2.sc.intel.com> References: <20201106232908.364581-1-ira.weiny@intel.com> <20201106232908.364581-6-ira.weiny@intel.com> <87mtzi8n0z.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87mtzi8n0z.fsf@nanos.tec.linutronix.de> User-Agent: Mutt/1.11.1 (2018-12-01) X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sun, Nov 15, 2020 at 07:58:52PM +0100, Thomas Gleixner wrote: > Ira, > > On Fri, Nov 06 2020 at 15:29, ira weiny wrote: > > Subject prefix wants to 'entry:'. This changes generic code and the x86 > part is just required to fix the generic code change. Sorry, yes that was carried incorrectly from earlier versions. > > > Currently struct irqentry_state_t only contains a single bool value > > which makes passing it by value is reasonable. However, future patches > > propose to add information to this struct, for example the PKRS > > register/thread state. > > > > Adding information to irqentry_state_t makes passing by value less > > efficient. Therefore, change the entry/exit calls to pass irq_state by > > reference. > > The PKRS muck needs to add an u32 to that struct. So how is that a > problem? There are more fields to be added for the kmap/pmem support. So this will be needed eventually. Even though it is not strictly necessary in the next patch. > > The resulting struct still fits into 64bit which is by far more > efficiently passed by value than by reference. So which problem are you > solving here? I'm getting ahead of myself a bit. I will be adding more fields for the kmap/pmem tracking. Would you accept just a clean up for the variable names in this patch? I could then add the pass by reference when I add the new fields later. Or would an update to the commit message be ok to land this now? Ira > > Thanks > > tglx >