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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F2B95C433EF for ; Tue, 16 Nov 2021 18:18:38 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BCA3861A7D for ; Tue, 16 Nov 2021 18:18:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org BCA3861A7D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=94p/6qC/MhHy/Sk6p1DziOZjH48ILdcUEEKpWhiw9WY=; b=A7tANPXn3Pdsq9 dncb/R83wgIBi+WQrhsfRl+VV4OG0tN6ec25wO8zAyepQlr3vqmUi1KLCoUNejGOkCGKoiu6pFHp7 yNGvAM7nN0CPUO4v6AINvEzt1E3wrlzpg/mzQS75r9jHSxRumRV/S/SJlT9Lgn7/FmgkGXsgKdHFi aLCRUKnd0BqArdwPT9k8P6qVCZ6eQiiPlHZMQkMS84CyPhKS/dOsenumrrslFJDFS6M8D+2qjXhxv j7FceCJfrXBYAV8vds7JRbgPJ2w8MpS9RV0YRWJmNuVJdfVYjdCLmZD4NgneS+lbQzbxBsgcwo/nF 0Nh8MeodEo0Xjqu/Furw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mn31G-002Y8F-1D; Tue, 16 Nov 2021 18:17:22 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mn31C-002Y6x-5A for linux-arm-kernel@lists.infradead.org; Tue, 16 Nov 2021 18:17:19 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id AA04A61A79; Tue, 16 Nov 2021 18:17:15 +0000 (UTC) Date: Tue, 16 Nov 2021 18:17:12 +0000 From: Catalin Marinas To: Guanghui Feng Cc: will@kernel.org, maz@kernel.org, qperret@google.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, baolin.wang@linux.alibaba.com, zhuo.song@linux.alibaba.com, zhangliguang@linux.alibaba.com Subject: Re: [PATCH] arm64: clear_page: use stnp non-temporal instruction for performance optimizing Message-ID: References: <1637075294-30747-1-git-send-email-guanghuifeng@linux.alibaba.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1637075294-30747-1-git-send-email-guanghuifeng@linux.alibaba.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211116_101718_238082_41CC3644 X-CRM114-Status: UNSURE ( 9.49 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Nov 16, 2021 at 11:08:14PM +0800, Guanghui Feng wrote: > When clear page mem, there is no need to alloc cache for storing these > mem value. I theory, DC ZVA is supposed to trigger write streaming mode and all writes go directly to memory avoiding cache allocation. > And the copy_page.S have used stnp instruction for optimizing. > So I rewrite the clear_page.S with stnp. At the same time, I have tested it > with stnp instruction which will get about twice the performance improvement. On which CPU implementation? Is the same improvement seen on a wider range of CPUs? -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel