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=-10.5 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 D5669C07E9B for ; Tue, 20 Jul 2021 13:59:30 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 634B3610F7 for ; Tue, 20 Jul 2021 13:59:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 634B3610F7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:43804 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m5qHR-0000bb-KY for qemu-devel@archiver.kernel.org; Tue, 20 Jul 2021 09:59:29 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35186) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m5qGV-0008CK-PS for qemu-devel@nongnu.org; Tue, 20 Jul 2021 09:58:31 -0400 Received: from mail-il1-x12b.google.com ([2607:f8b0:4864:20::12b]:37729) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1m5qGT-0001Pl-Ju for qemu-devel@nongnu.org; Tue, 20 Jul 2021 09:58:31 -0400 Received: by mail-il1-x12b.google.com with SMTP id o8so19214476ilf.4 for ; Tue, 20 Jul 2021 06:58:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=j8m7O3nzctdMpwynFD7KZJUAUeW65EE5Ui4etbpVfB4=; b=mDCo21bUeulA1IDay5t0M5oxnW2VlIr0Ji1NqJiljMa46pOR9RFXXopY+PTwkov1IS SPHeR2kUDgnTyYo2ylkJIcC51WF+dcAcK2NgfMtVf4jRJOMLEtgKbu1ppo+0bAffzQiG 65xvn5nknNJY2Q8OikTvVTmovib/Qn6kMOm7c0sua4lD+yzW8XxJvkUHriu/dzvLNHw4 na+3l6MZqxk+MlxspEFRcakSOkYEZcUz7u//vLmFO7B8Mq/cIMiVRejIkWyowjlxV8M/ W3Yw6ctvv+mE8LVjBWGTHCLe6acwd/sxRweP9iAwRU7I9KuFBk48qsaL7Xdpttn00JHV 2zZQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=j8m7O3nzctdMpwynFD7KZJUAUeW65EE5Ui4etbpVfB4=; b=p32+ZleJh5TCLknE/ZWaocxUR5W6aiU9qFMmqKsdRhDmBfWBE4HwLcJFjaeD9C/M78 IFenOCIb7VPdof10pSuJvuSJRQT3+PtaVTEACWtUlRpKuJPeZjPPO6tC3UHj+rmndDZC u5iiePAXu5TCFHvqWLmvltmkAgDeaED3pUU0QXqDJbnmGj6I9FHD5R10asZQRKyDG5Bt 1C4BUThZBAL1kXn0Rc4x3SzFIm7QA7iy1iKny3ZGs1n5drAlZTThB8MzYYSK4uZ4/WiZ eBBXtU+CXqiALL4xYVjS39wMEcI6GV+UBn7MN8wdYEEBAElKaBZTVV8ZJR2xdiGjSrVp yT7g== X-Gm-Message-State: AOAM5332g+WalKeIZFmZ1+3tlibRVWRQ63Nw4r9fiv/j/wDD+MX/ugc4 cWW9fU1ki3Ta1uHDyVwIppHpHooGcr0FPH6kLdk= X-Google-Smtp-Source: ABdhPJzVbZHOuBRt3WkJm41rV/akVTSasjoeSdCkFMM6zz9S/GHeOFyj95xUs2ozQdSAVHcvQvhj1XAsKywKWOhNLvM= X-Received: by 2002:a92:508:: with SMTP id q8mr21491709ile.89.1626789508290; Tue, 20 Jul 2021 06:58:28 -0700 (PDT) MIME-Version: 1.0 References: <20210714112306.67793-1-david@redhat.com> In-Reply-To: From: Pankaj Gupta Date: Tue, 20 Jul 2021 15:58:17 +0200 Message-ID: Subject: Re: [PATCH v1 0/3] util/oslib-posix: Support MADV_POPULATE_WRITE for os_mem_prealloc() To: David Hildenbrand Content-Type: text/plain; charset="UTF-8" Received-SPF: pass client-ip=2607:f8b0:4864:20::12b; envelope-from=pankaj.gupta.linux@gmail.com; helo=mail-il1-x12b.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , "Michael S. Tsirkin" , "Dr . David Alan Gilbert" , Qemu Developers , Igor Mammedov , Paolo Bonzini , Marek Kedzierski Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" > > #1 adds support for MADV_POPULATE_WRITE, #2 cleans up the code to avoid > > global variables and prepare for concurrency and #3 makes os_mem_prealloc() > > safe to be called from multiple threads concurrently. > > > > Details regarding MADV_POPULATE_WRITE can be found in introducing upstream > > Linux commit 4ca9b3859dac ("mm/madvise: introduce > > MADV_POPULATE_(READ|WRITE) to prefault page tables") and in the latest man > > page patch [1]. > > > > [1] https://lkml.kernel.org/r/20210712083917.16361-1-david@redhat.com > > > > Cc: Paolo Bonzini > > Cc: "Michael S. Tsirkin" > > Cc: Igor Mammedov > > Cc: Eduardo Habkost > > Cc: Dr. David Alan Gilbert > > Cc: Marek Kedzierski > > Cc: Pankaj Gupta > > > > David Hildenbrand (3): > > util/oslib-posix: Support MADV_POPULATE_WRITE for os_mem_prealloc() > > util/oslib-posix: Introduce and use MemsetContext for > > touch_all_pages() > > util/oslib-posix: Support concurrent os_mem_prealloc() invocation > > > > include/qemu/osdep.h | 7 ++ > > util/oslib-posix.c | 167 ++++++++++++++++++++++++++++++------------- > > 2 files changed, 126 insertions(+), 48 deletions(-) > > > > Nice implementation to avoid wear of memory device for prealloc case For prealloc case I mean. > and to avoid touching of > all the memory and abrupt exit of VM because of lack of memory. Instead better > way to populate the page tables with madvise. > > Plan is to use this infrastructure for virtio-mem, I guess? > > For the patches 1 & 3: > Reviewed-by: Pankaj Gupta > > > Thanks, > Pankaj