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=-1.1 required=3.0 tests=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 699B0C433DF for ; Tue, 23 Jun 2020 09:07:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 22F8D20702 for ; Tue, 23 Jun 2020 09:07:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="O8JG556f" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732213AbgFWJHe (ORCPT ); Tue, 23 Jun 2020 05:07:34 -0400 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:22642 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1731973AbgFWJH2 (ORCPT ); Tue, 23 Jun 2020 05:07:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1592903246; 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=xUhedPr/j0Zt6HlxSwFeY7buhUrUP8KB8aI1O09bZl0=; b=O8JG556fKAX/wHTsqjad+ueQJH1Hsx4eb16YAhn/aP6T+Bku7oyblOzUm0JEKWvGc3FGz5 V4jtKrEUCgaqgI6z8cNK8lkcBZchlXsh/tA8hB+bfN/yMeelDGHy9z5jKpBSMpCUkAuClI LVy/3oIWCXVeJn/4IWk7kX0iufuYvps= Received: from mail-ed1-f72.google.com (mail-ed1-f72.google.com [209.85.208.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-226-eZ4iTMOGNsak_3TE5F9RgA-1; Tue, 23 Jun 2020 05:07:24 -0400 X-MC-Unique: eZ4iTMOGNsak_3TE5F9RgA-1 Received: by mail-ed1-f72.google.com with SMTP id z8so9969122edr.12 for ; Tue, 23 Jun 2020 02:07:24 -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=xUhedPr/j0Zt6HlxSwFeY7buhUrUP8KB8aI1O09bZl0=; b=ltcCnGFJ9F7r72MHBBKfUJU+yWS5KGR+7bGgf/eaBWUBlLxW+4OG92oam/IK9VsUtd CiQMOzKAnqHQVjPqpTbM6/xc/JV1JjHKYXQjf2PQfld4RXb6RKGZ8/0dJS/4EtfIXJjS m4shOeRiv0pSLJSoWtJlB1jSDQPxXiG1F/QjNB2CNufwe8mu/WPfbXVtlN9yFLgdQyZY sxKiHZD64nsgUNcM9CDvA1I6iumaaGN7FJLoM1f9tEZur5HuGA/F19DQrHchQcNFLl3E K5LNJTBI4aXzzGTNfcrqQvdylvgAlvSt9zWApuVAASjvEjmk+hDrqe2Cokeyv8Qe2M9u XJEg== X-Gm-Message-State: AOAM530g7jSljQoHeAjlRUz0s0qa83pH5NecfXFfCYoXTv0/ujmI77AE NdwSMIfCdXKLeL7ihZrDcF4weanLhVYHNPW1Dk6Fe1aGQ0Y6i4a+HFKjWr/JGYaWhuhiD37W690 ZpWWN1ky2JTC/pX06OLUwTD2x X-Received: by 2002:a17:907:7283:: with SMTP id dt3mr19954359ejc.195.1592903243232; Tue, 23 Jun 2020 02:07:23 -0700 (PDT) X-Google-Smtp-Source: ABdhPJw972fIHdUzv66dXpLtZVIXmYxb51SJLbr0O/Yf+RV8EuSjV+zcR4Y3hr8taeCbChsNVy6uCg== X-Received: by 2002:a17:907:7283:: with SMTP id dt3mr19954335ejc.195.1592903242968; Tue, 23 Jun 2020 02:07:22 -0700 (PDT) Received: from localhost ([2001:470:5b39:29:79fc:ff4e:48ab:b845]) by smtp.gmail.com with ESMTPSA id z1sm13289301eji.92.2020.06.23.02.07.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Jun 2020 02:07:22 -0700 (PDT) Date: Tue, 23 Jun 2020 11:07:21 +0200 From: Oleksandr Natalenko To: Minchan Kim Cc: Andrew Morton , LKML , Christian Brauner , linux-mm , linux-api@vger.kernel.org, Suren Baghdasaryan , Tim Murray , Sandeep Patil , Sonny Rao , Brian Geffon , Michal Hocko , Johannes Weiner , Shakeel Butt , John Dias , Joel Fernandes , Jann Horn , alexander.h.duyck@linux.intel.com, sj38.park@gmail.com, David Rientjes , Arjun Roy Subject: Re: [PATCH v8 0/4] introduce memory hinting API for external process Message-ID: <20200623090721.5owt4cxjji6isqe3@butterfly.localdomain> References: <20200622192900.22757-1-minchan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200622192900.22757-1-minchan@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 22, 2020 at 12:28:56PM -0700, Minchan Kim wrote: > Now, we have MADV_PAGEOUT and MADV_COLD as madvise hinting API. With that, > application could give hints to kernel what memory range are preferred to be > reclaimed. However, in some platform(e.g., Android), the information > required to make the hinting decision is not known to the app. > Instead, it is known to a centralized userspace daemon(e.g., ActivityManagerService), > and that daemon must be able to initiate reclaim on its own without any app > involvement. > > To solve the concern, this patch introduces new syscall - process_madvise(2). > Bascially, it's same with madvise(2) syscall but it has some differences. > > 1. It needs pidfd of target process to provide the hint > 2. It supports only MADV_{COLD|PAGEOUT} at this moment. > Other hints in madvise will be opened when there are explicit requests from > community to prevent unexpected bugs we couldn't support. > 3. Only privileged processes can do something for other process's address > space. > > For more detail of the new API, please see "mm: introduce external memory hinting API" > description in this patchset. > > * from v7 - http://lore.kernel.org/r/20200302193630.68771-1-minchan@kernel.org > * dropping pid support from new syscall and fold releated patches into syscall patch > * dropping KSM patch by discussion - Oleksandr, I lost the discussion. > Please resend the single patch against of the patchset if you resolves the discussion. > https://lore.kernel.org/linux-api/20200302193630.68771-8-minchan@kernel.org/ What "next" tag this (v8) submission is based on please? > * from v6 - https://lore.kernel.org/linux-api/20200219014433.88424-1-minchan@kernel.org/ > * fix comments and descriptions - Suren > * Add Reviewed-by - Suren > * fix build break reported by 0-day > > * from v5 - https://lore.kernel.org/linux-mm/20200214170520.160271-1-minchan@kernel.org/ > * use null task and requestor's mm for io_madvise - Jann and Jens > * use right commit description for moving pidfd_get_pid - Christoph > > * from v4 - https://lore.kernel.org/linux-mm/20200212233946.246210-1-minchan@kernel.org/ > * pass mm down to functions, not accessing task->mm - Jann > * clean up - Alexander > * add Reviewed-by - Alexander, SeongJae > * patch reordering > > * from v3 - https://lore.kernel.org/linux-mm/20200128001641.5086-1-minchan@kernel.org/ > * verify task->mm aftere access_mm - Oleg > * split some patches for easy review - Alexander > * clean up fatal signal checking - Suren > > * from v2 - https://lore.kernel.org/linux-mm/20200116235953.163318-1-minchan@kernel.org/ > * check signal callee and caller to bail out - Kirill Tkhai > * put more clarification for justification of new API > > * from v1 - https://lore.kernel.org/linux-mm/20200110213433.94739-1-minchan@kernel.org/ > * fix syscall number - SeongJae > * use get_pid_task - Kirill Tkhai > * extend API to support pid as well as pidfd - Kirill Tkhai > > Minchan Kim (4): > mm/madvise: pass task and mm to do_madvise > pid: move pidfd_get_pid() to pid.c > mm/madvise: introduce process_madvise() syscall: an external memory > hinting API > mm/madvise: check fatal signal pending of target process > > arch/alpha/kernel/syscalls/syscall.tbl | 1 + > arch/arm/tools/syscall.tbl | 1 + > arch/arm64/include/asm/unistd.h | 2 +- > arch/arm64/include/asm/unistd32.h | 2 + > arch/ia64/kernel/syscalls/syscall.tbl | 1 + > arch/m68k/kernel/syscalls/syscall.tbl | 1 + > arch/microblaze/kernel/syscalls/syscall.tbl | 1 + > arch/mips/kernel/syscalls/syscall_n32.tbl | 1 + > arch/mips/kernel/syscalls/syscall_n64.tbl | 1 + > arch/mips/kernel/syscalls/syscall_o32.tbl | 1 + > arch/parisc/kernel/syscalls/syscall.tbl | 1 + > arch/powerpc/kernel/syscalls/syscall.tbl | 1 + > arch/s390/kernel/syscalls/syscall.tbl | 1 + > arch/sh/kernel/syscalls/syscall.tbl | 1 + > arch/sparc/kernel/syscalls/syscall.tbl | 1 + > arch/x86/entry/syscalls/syscall_32.tbl | 1 + > arch/x86/entry/syscalls/syscall_64.tbl | 2 + > arch/xtensa/kernel/syscalls/syscall.tbl | 1 + > fs/io_uring.c | 2 +- > include/linux/compat.h | 4 + > include/linux/mm.h | 3 +- > include/linux/pid.h | 1 + > include/linux/syscalls.h | 2 + > include/uapi/asm-generic/unistd.h | 4 +- > kernel/exit.c | 17 -- > kernel/pid.c | 17 ++ > kernel/sys_ni.c | 2 + > mm/madvise.c | 190 +++++++++++++++++--- > 28 files changed, 217 insertions(+), 46 deletions(-) > > -- > 2.27.0.111.gc72c7da667-goog > -- Best regards, Oleksandr Natalenko (post-factum) Principal Software Maintenance Engineer