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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 3F1BEC55186 for ; Thu, 23 Apr 2020 09:09:37 +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 037EB2075A for ; Thu, 23 Apr 2020 09:09:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Ijxg3z9H" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 037EB2075A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject: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=PehXpmux0PIv+DDV2otfZEfdMaej1AAwBxeyA5V921k=; b=Ijxg3z9HNpgLne fLG5Gp3qlDV21IT+A0wKz1ae/dnwAXUk1AyDpP8zAIqsVtfEEjYKaYBbfnTvwCJ7o5yh+IITgva// 8PeHqtZEVdQOB2IUg6QJMJqyHionla51OfQqSGLnQTJbhrVrMMYKxR4V8CGLAecdNK9WsojmHOy7h 96FA1L/wGidbsh7HYtCrajif0G1QhTOfX78hLK5SIRneH6wiEKh6EhnwV8pHRxu2wuz7fEeqqPBwX jeNx5jKhCBDhk8vgzDNYQlFEPaloFVKh8f8wdDX+AwbpNh36KtLp1LymMHJVeXRgZRfBjqAX1JJQT dtc4RT1Ncw0W2mOCDWzQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jRXrU-0004gI-4r; Thu, 23 Apr 2020 09:09:36 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jRXrR-0004ey-6X for linux-arm-kernel@lists.infradead.org; Thu, 23 Apr 2020 09:09:34 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5716D31B; Thu, 23 Apr 2020 02:09:28 -0700 (PDT) Received: from gaia (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E58E43F73D; Thu, 23 Apr 2020 02:09:26 -0700 (PDT) Date: Thu, 23 Apr 2020 10:09:20 +0100 From: Catalin Marinas To: Dave Hansen Subject: Re: [PATCH 2/4] mm: Add arch hooks for saving/restoring tags Message-ID: <20200423090919.GA4963@gaia> References: <20200422142530.32619-1-steven.price@arm.com> <20200422142530.32619-3-steven.price@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200423_020933_284373_83D03C12 X-CRM114-Status: GOOD ( 11.18 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, Arnd Bergmann , Hugh Dickins , Steven Price , linux-mm@kvack.org, Andrew Morton , Vincenzo Frascino , Will Deacon , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Apr 22, 2020 at 11:08:10AM -0700, Dave Hansen wrote: > On 4/22/20 7:25 AM, Steven Price wrote: > > Three new hooks are added to the swap code: > > * arch_prepare_to_swap() and > > * arch_swap_invalidate_page() / arch_swap_invalidate_area(). > > One new hook is added to shmem: > > * arch_swap_restore_tags() > > How do the tags get restored outside of the shmem path? I was expecting > to see more arch_swap_restore_tags() sites. The restoring is done via set_pte_at() -> mte_sync_tags() -> mte_restore_tags() in the arch code (see patch 3). arch_swap_restore_tags() just calls mte_restore_tags() directly. shmem is slightly problematic as it moves the page from the swap cache to the shmem one and I think arch_swap_invalidate_page() would have already been called by the time we get to set_pte_at() (Steven can correct me if I got this wrong). -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel