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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 9942FC43461 for ; Tue, 15 Sep 2020 22:26:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 551CC20809 for ; Tue, 15 Sep 2020 22:26:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="cXUnQ+HR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727695AbgIOW01 (ORCPT ); Tue, 15 Sep 2020 18:26:27 -0400 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:42551 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727550AbgIOQV2 (ORCPT ); Tue, 15 Sep 2020 12:21:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600186862; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=GfwuuWWzGYHhzmOr9zWk/h6mAKg0sY0tXHg31ZT1k8E=; b=cXUnQ+HRVUKb77v4Qww3cvk3lW4YnjluSQ7RTf6dIVIRyhrBX/fVmcZVTSwB2zOajpUDPb A4dULSyiq+eNqwNnmzhbtwvOaMjMUvVVy9DLrwb0TWG50tf+WP4fMrUau3nI8db5wLq8TZ wybX+sYg4pK9zWI2ZVJgf/rE1uj9Eh8= Received: from mail-qk1-f198.google.com (mail-qk1-f198.google.com [209.85.222.198]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-219-zz05hMA8MQ-fM1QL7GojgQ-1; Tue, 15 Sep 2020 12:18:17 -0400 X-MC-Unique: zz05hMA8MQ-fM1QL7GojgQ-1 Received: by mail-qk1-f198.google.com with SMTP id m203so3225973qke.16 for ; Tue, 15 Sep 2020 09:18:17 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=GfwuuWWzGYHhzmOr9zWk/h6mAKg0sY0tXHg31ZT1k8E=; b=QU9hzSD0mohPzzqdnJRxB/bt4zIOB99MhMjHu5vU6s8XpjYoYtZ7nxLpSZsa03DtB5 pb/vX78y1iJhdFqAV2WKaZIKYuq6GYU3lwbkfTMTNPsI2ydUrP5QhHPh+VPMM+5+dIAR HQ5dg8EOBmIBdtlf3sG+0/Iiq2wkPazYtAuQFyVY+idfNoVSxUk624UJDsxawYrghShD zc3lOdNDmMf2MbnOIaxoIb0xK6VR6Q/zS+hq7mX9+bRF2WiUZGA4vo5evhtmGmpGAv+m VWiYYyTdp/tD2l2mgG5WtcKYmvjil0D6wdHvDQZZspTcIVSWLvuVGnPO/LqptJYvwBdS yQsQ== X-Gm-Message-State: AOAM5322wCUIoj8HVpANtQZf5TUGgOj5hf77pVS2dp0/378T+eV6uQlR eloejhK8caCYfpM5Vn8c53w8eGL0IgoyxbXQ3sMSi0BoHY/evyEsBMlzDl1f5KEb395wSVeLL9z HzjWAquP3aEzTOr6j/i++Hn1f X-Received: by 2002:a37:64d4:: with SMTP id y203mr18363458qkb.359.1600186697195; Tue, 15 Sep 2020 09:18:17 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwLVW8kuvMeh2di7XK6DC3uhyQVMeMlC0qltufBS9xG4VLH4xrOs73HZvyOAteqZrQAnOU8WA== X-Received: by 2002:a37:64d4:: with SMTP id y203mr18363431qkb.359.1600186696948; Tue, 15 Sep 2020 09:18:16 -0700 (PDT) Received: from xz-x1 (bras-vprn-toroon474qw-lp130-11-70-53-122-15.dsl.bell.ca. [70.53.122.15]) by smtp.gmail.com with ESMTPSA id u46sm16483548qth.31.2020.09.15.09.18.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 15 Sep 2020 09:18:15 -0700 (PDT) Date: Tue, 15 Sep 2020 12:18:14 -0400 From: Peter Xu To: Oleg Nesterov Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Maya B . Gokhale" , Linus Torvalds , Yang Shi , Marty Mcfadden , Kirill Shutemov , Jann Horn , Jan Kara , Kirill Tkhai , Andrea Arcangeli , Christoph Hellwig , Andrew Morton Subject: Re: [PATCH 1/4] mm: Trial do_wp_page() simplification Message-ID: <20200915161814.GC2949@xz-x1> References: <20200821234958.7896-1-peterx@redhat.com> <20200821234958.7896-2-peterx@redhat.com> <20200915150349.GA22415@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200915150349.GA22415@redhat.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Sep 15, 2020 at 05:03:49PM +0200, Oleg Nesterov wrote: > > - if (reuse_swap_page(vmf->page, &total_map_swapcount)) { > > It seems that nobody else calls reuse_swap_page() with total_map_swapcount != NULL. Seems correct. Though maybe we could postpone the cleanup later, until the fallouts of the cow rework settle (just in case we'd like to bring some mapcount logic back). Thanks, -- Peter Xu