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=-13.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 A5FD9C432BE for ; Mon, 2 Aug 2021 19:54:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8D81E60F36 for ; Mon, 2 Aug 2021 19:54:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230126AbhHBTyO (ORCPT ); Mon, 2 Aug 2021 15:54:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45888 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229663AbhHBTyN (ORCPT ); Mon, 2 Aug 2021 15:54:13 -0400 Received: from mail-yb1-xb2e.google.com (mail-yb1-xb2e.google.com [IPv6:2607:f8b0:4864:20::b2e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D9A7C061760 for ; Mon, 2 Aug 2021 12:54:03 -0700 (PDT) Received: by mail-yb1-xb2e.google.com with SMTP id z18so3583841ybg.8 for ; Mon, 02 Aug 2021 12:54:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=r51pjfza8s2HZE4XW/GNL6Iowf+AIDCryqM3vDA5jF0=; b=DAYvA9rfP2uv0YWaF+1ehuOCq1YPB/a8+QNZRahtWdRbWaD6MEOHky451k9S8b7xeG B2Im902DswK42N/fylfIy3bOexB+GE0C9pLTSfbmBoR4Cm46UH7IIM4/TLdJqLcGQbsP w/PDxJq7kELy9/mdLj9CGkJhECn9IYBK7zNzfvZPtC5p0lWvbVsrj1fZT9mxL/2Y9I8N dOeFqVAloLTVBWcrlMMpvIBaCcquN2VC6GsGjlTXUVzoQKjcN3b2AHjIza5a0Gnrbu8B AS9CehPVUNe/wPrQJ4DPXbO8IuHri/i7LMBKnikgsKmNSyKLkE6gDAVangHIhcTq14go Bwxg== 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=r51pjfza8s2HZE4XW/GNL6Iowf+AIDCryqM3vDA5jF0=; b=pDp8Y4K+xDfUhnu9+nbI2Sp0Bn8GwjNX8GagDfZqJqNP+xvL7EWQ22NrDwTN3FL29z Sp4QTqOhICMRVnrzs01SFMM887OhBo1Zt+estk0AXEyyK7ontew6AX/SRckuxt/cKkNc P+BUMqseu/8Xxkpclu2Cw5FKuhEkZkEs2gr8AZHV6HALFqIVJY0azE5aPL7+0R/IXUNk vnzRvvQbOEVNgRCi9K88NUXE7HCSWEZxvXdyRLHRoBTLoBDQXULYW9CiNIEMmwpmdQb6 Cwt52zdkcRyWtPwPAu9/JsNrUgdX3w8YFk1/59hxcA4je608A2QtIkjFGrpuB+tS3NlZ MaTA== X-Gm-Message-State: AOAM533lXdmxP0o78bWh05HZECRICdzHES9PkOfoyEilpUXqJDx7i+EI wXppitx89WNER/P1NOjROKlrsxiItmAYLNe/AgfzLQ== X-Google-Smtp-Source: ABdhPJxpo6fn/Ec+BXl6VDLMbnEoz80RcLHLkmWuS2+jWCgCgL5B6GLoLxGdD9dM5qOafDXt/CjrVtAJ+R98d8uKhMQ= X-Received: by 2002:a25:7ec4:: with SMTP id z187mr23611603ybc.136.1627934042111; Mon, 02 Aug 2021 12:54:02 -0700 (PDT) MIME-Version: 1.0 References: <20210723011436.60960-1-surenb@google.com> In-Reply-To: From: Suren Baghdasaryan Date: Mon, 2 Aug 2021 12:53:51 -0700 Message-ID: Subject: Re: [PATCH v3 1/2] mm: introduce process_mrelease system call To: Shakeel Butt Cc: Michal Hocko , Andrew Morton , David Rientjes , Matthew Wilcox , Johannes Weiner , Roman Gushchin , Rik van Riel , Minchan Kim , Christian Brauner , Christoph Hellwig , Oleg Nesterov , David Hildenbrand , Jann Horn , Andy Lutomirski , Christian Brauner , Florian Weimer , Jan Engelhardt , Tim Murray , Linux API , Linux MM , LKML , kernel-team Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 26, 2021 at 6:44 AM Shakeel Butt wrote: > > On Mon, Jul 26, 2021 at 12:27 AM Michal Hocko wrote: > > > [...] > > > > Is process_mrelease on all of them really necessary? I thought that the > > primary reason for the call is to guarantee a forward progress in cases > > where the userspace OOM victim cannot die on SIGKILL. That should be > > more an exception than a normal case, no? > > > > I am thinking of using this API in this way: On user-defined OOM > condition, kill a job/cgroup and unconditionally reap all of its > processes. Keep monitoring the situation and if it does not improve go > for another kill and reap. > > I can add additional logic in between kill and reap to see if reap is > necessary but unconditionally reaping is more simple. > > > > > > An alternative would be to have a cgroup specific interface for > > > reaping similar to cgroup.kill. > > > > Could you elaborate? > > > > I mentioned this in [1] where I was thinking if it makes sense to > overload cgroup.kill to also add the SIGKILLed processes in > oom_reaper_list. The downside would be that there will be one thread > doing the reaping and the syscall approach allows userspace to reap in > multiple threads. I think for now, I would go with whatever Suren is > proposing and we can always add more stuff if need arises. > > [1] https://lore.kernel.org/containers/CALvZod4jsb6bFzTOS4ZRAJGAzBru0oWanAhezToprjACfGm+ew@mail.gmail.com/ Hi Folks, So far I don't think there was any request for further changes. Anything else you would want me to address or are we in a good shape wrt this feature? If so, would people who had a chance to review this patchset be willing to endorse it with their Reviewed-by or Acked-by? Thanks, Suren.