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=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 5CF81C10F26 for ; Wed, 1 Apr 2020 12:32:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 32AA420714 for ; Wed, 1 Apr 2020 12:32:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="WTj9rUoG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732478AbgDAMcg (ORCPT ); Wed, 1 Apr 2020 08:32:36 -0400 Received: from mail-lj1-f195.google.com ([209.85.208.195]:33931 "EHLO mail-lj1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732166AbgDAMcf (ORCPT ); Wed, 1 Apr 2020 08:32:35 -0400 Received: by mail-lj1-f195.google.com with SMTP id p10so25316540ljn.1; Wed, 01 Apr 2020 05:32:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=8L1/PQnaYBXbzEXUweVQSVAcSQPDyAlUiX0T3JYuuFY=; b=WTj9rUoGT58FPH1IwytfIF8RhdaoHlpu/RcEVNmQlRH2NJFfn6hoxF+2xB1d56SnnK SkZwxfmiR21dCYC/Sy0hQbd5OKqPU+IUF9zvQc7vgtNIvWKf2sdBlX27FQf4V7qxpcZ3 d3RiayaUKlnU4Mc3IsTfY4R3V3tBt2+eZO/2R1JF4DRFe1aoIGa/yjgShd1KHrB0yhLZ gGryc5zPaSm6VmCTI/+DxVzJLIRvIPtkhvMua38Ja2OCEWr9HRbdCjEC9fq+xL9iakwh g0JwFYpEPuZUxT4aukz2BGVcSXXjoqCUhK/pP5qmDKtjccjgX0+h6jFrJYTqNMR3YynL +PvA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=8L1/PQnaYBXbzEXUweVQSVAcSQPDyAlUiX0T3JYuuFY=; b=Xk1agpHaHe9ZuVohmLsAVZBf70RHC0Nvt7sHDD3Tnc3Yg/MHb42n2lu7QjuG6WMmr6 DCltfY5zhhWZnKJxmi/XZdDeHURITuCe5T/VgUye5Q1beob1y8YZ4KpRKjpfQhjtJY8h q0ozzEaShsQZ06phhb6Lt/SBeB/M+IBo27kWMwAzcV1XDYtMX4XNPktICvdkbXBAIjkf w/pMF1p+wlx1BLczPEB62YZ246Yo8SXiVUkRF/wJdZFFHq/yCiHbFjP22Aw5jNT95sou hylU2SXDSreKR1lQCLuUnrzFJttzwMmzqZJQ1wFEnlDGyPeYtLsZe2rsuU8Ur41XFt/6 NJKg== X-Gm-Message-State: AGi0PuZ/aw6XZRRXg85nCavXnwcUaP2Rd8zJEpbCKx8Go4wb+wnDWDq6 eSXg2aGQgJceOvQUUAH50uw= X-Google-Smtp-Source: APiQypJPwFtOAJ2kUBAdMVY1kqthd4AAiL4fiBBSlc6OWULAJhNSrhHxOjfin2SD/kjs0urj7hF1fw== X-Received: by 2002:a05:651c:1a5:: with SMTP id c5mr13087568ljn.113.1585744353370; Wed, 01 Apr 2020 05:32:33 -0700 (PDT) Received: from pc636 (h5ef52e31.seluork.dyn.perspektivbredband.net. [94.245.46.49]) by smtp.gmail.com with ESMTPSA id a10sm1531864lfg.33.2020.04.01.05.32.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Apr 2020 05:32:32 -0700 (PDT) From: Uladzislau Rezki X-Google-Original-From: Uladzislau Rezki Date: Wed, 1 Apr 2020 14:32:30 +0200 To: Michal Hocko Cc: Uladzislau Rezki , Joel Fernandes , linux-kernel@vger.kernel.org, linux-mm@kvack.org, rcu@vger.kernel.org, willy@infradead.org, peterz@infradead.org, neilb@suse.com, vbabka@suse.cz, mgorman@suse.de, Andrew Morton , Josh Triplett , Lai Jiangshan , Mathieu Desnoyers , "Paul E. McKenney" , Steven Rostedt Subject: Re: [PATCH RFC] rcu/tree: Use GFP_MEMALLOC for alloc memory to free memory pattern Message-ID: <20200401123230.GB32593@pc636> References: <20200331131628.153118-1-joel@joelfernandes.org> <20200331145806.GB236678@google.com> <20200331153450.GM30449@dhcp22.suse.cz> <20200331161215.GA27676@pc636> <20200401070958.GB22681@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200401070958.GB22681@dhcp22.suse.cz> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 01, 2020 at 09:09:58AM +0200, Michal Hocko wrote: > On Tue 31-03-20 18:12:15, Uladzislau Rezki wrote: > > > > > > __GFP_ATOMIC | __GFP_HIGH is the way to get an additional access to > > > memory reserves regarless of the sleeping status. > > > > > Michal, just one question here regarding proposed flags. Can we also > > tight it with __GFP_RETRY_MAYFAIL flag? Means it also can repeat a few > > times in order to increase the chance of being success. > > yes, __GFP_RETRY_MAYFAIL is perfectly valid with __GFP_ATOMIC. Please > note that __GFP_ATOMIC, despite its name, doesn't imply an atomic > allocation which cannot sleep. Quite confusing, I know. A much better > name would be __GFP_RESERVES or something like that. > OK. Then we can use GFP_ATOMIC | __GFP_RETRY_MAYFAIL to try in more harder way. Thanks! -- Vlad Rezki