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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id A754AC41513 for ; Fri, 28 Jul 2023 11:13:12 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 1D7A06B0075; Fri, 28 Jul 2023 07:13:12 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 15FA76B0078; Fri, 28 Jul 2023 07:13:12 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0277F8D0001; Fri, 28 Jul 2023 07:13:11 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id E59B66B0075 for ; Fri, 28 Jul 2023 07:13:11 -0400 (EDT) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 9A595C054A for ; Fri, 28 Jul 2023 11:13:11 +0000 (UTC) X-FDA: 81060758982.26.CB3C9D6 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf25.hostedemail.com (Postfix) with ESMTP id E50BEA0008 for ; Fri, 28 Jul 2023 11:13:09 +0000 (UTC) Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=linuxfoundation.org header.s=korg header.b=mGv7o46b; dmarc=pass (policy=none) header.from=linuxfoundation.org; spf=pass (imf25.hostedemail.com: domain of gregkh@linuxfoundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1690542790; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=JpaDbcjM+NCZtzUygGokm1IvU3XMZ0crzyV7w/JBbM4=; b=RVVAheKCX50DNklS76zgx6ClUn9/KK+9Alph6zhHpXNUjJc4Qy8aHjEggpniN7fEKRXeTJ pFELOqVgsK7sTshggM9kQwcdjp8D3fKs6UoiWcTMmZCIhgdUyae1YTEXez8ZrfgqjiHuLx 8JfF6LAdDoxR1Vit2l7veoFhSPi/YgA= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=linuxfoundation.org header.s=korg header.b=mGv7o46b; dmarc=pass (policy=none) header.from=linuxfoundation.org; spf=pass (imf25.hostedemail.com: domain of gregkh@linuxfoundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=gregkh@linuxfoundation.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1690542790; a=rsa-sha256; cv=none; b=V5By6GwQNLATCw+BD1f/Om/mcme9/dz8ljOtA6hqeNN9TE+skVIp0zeVUDD+QDq56xaibY j9vDq1iyBhZJqzsDJS7W4TlPWb0QShsbAb7dYyPTWX40dOuINf3y1gxeiT1dGik7zYoykh aqzBAEqSdUHM4E4oF1ChHrDhX3wlgIA= Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 154FA620FB; Fri, 28 Jul 2023 11:13:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E85DCC433C8; Fri, 28 Jul 2023 11:13:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1690542788; bh=SXf0CvhgUkGm+fNUV5KHDN/D2FZxDlPPjw5urZT6Keo=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mGv7o46bKMQNQnFbWlWW3EHhpoXV4D8cil6h9KcxnevCmI3Ao5DqUZ3WkB1xbx+s6 nrXbrhJPUlIv0ajoKUAB1wwvHp5kdNLesTg8KDWLeZhwV14QJgRqyx0vVFnQcabl+p oIvW56PEpsXwGaCujj1wPVF8JlShTANqmOVIWzCQ= Date: Fri, 28 Jul 2023 13:13:05 +0200 From: Greg KH To: Muhammad Usama Anjum Cc: =?utf-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= , Paul Gofman , Peter Xu , David Hildenbrand , Andrew Morton , Andrei Vagin , Danylo Mocherniuk , Cyrill Gorcunov , Mike Rapoport , Nadav Amit , Alexander Viro , Shuah Khan , Christian Brauner , Yang Shi , Vlastimil Babka , "Liam R . Howlett" , Yun Zhou , Suren Baghdasaryan , Alex Sierra , Matthew Wilcox , Pasha Tatashin , Axel Rasmussen , "Gustavo A . R . Silva" , Dan Williams , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, kernel@collabora.com, =?utf-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= Subject: Re: WIP: Performance improvements Message-ID: <2023072809-mowing-amaze-efb5@gregkh> References: <20230727093637.1262110-1-usama.anjum@collabora.com> <20230727093637.1262110-3-usama.anjum@collabora.com> <6b6a4e1c-a9e9-9592-d5b4-3c9210c8b650@collabora.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6b6a4e1c-a9e9-9592-d5b4-3c9210c8b650@collabora.com> X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: E50BEA0008 X-Stat-Signature: b95sb3mymtw37amega4dqmb9am9bsdkq X-HE-Tag: 1690542789-293253 X-HE-Meta: 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 s6kMB/Bt yie3B5x+UDfGjdeQ9yF45aL8Aru5H/OVMfN3C3iCp/CKECO4O+I4FoX495nYjsGzi6Ws64/x1/N3N5nwaXpmptJ5VzZTsUfh+doI4djmTznobZjJSruSLbcde1KC7uhfY3LSnLpcwzTXO7JUlz6CgRCzLGjQdqkl0fkA95UcuzogyKizf+x9Ho10/r6rpLRYIVsOG7EtyQSh+VS1yfcbnK9//9Scrf20U/ZqW5LqwAIjuSe8FR2oQQuQSvT+lrhMhdtcJVABG3SSCV+7Lx1iSxLXyi390c6gkgpXdvTtlJ4e3kK1tHGFRelUhyA== 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 Fri, Jul 28, 2023 at 04:02:02PM +0500, Muhammad Usama Anjum wrote: > We are optimizing for more performance. Please find the change-set below > for easy review before next revision and post your comments: > > - Replace memcpy() with direct copy as it proving to be very expensive > - Don't check if PAGE_IS_FILE if no mask needs it as it is very > expensive to check per pte > - Add question in comment for discussion purpose > - Add fast path for exclusive WP for ptes Please read the kernel documentation for how to properly submit patches (i.e. don't mush them all together into one and then properly describe what you are doing and why you are doing it). Also actually test the patch and prove (or disprove) if it does matter for performance. good luck! greg k-h