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=-8.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 4D433C388F7 for ; Thu, 22 Oct 2020 12:44:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E33E622267 for ; Thu, 22 Oct 2020 12:44:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2898633AbgJVMof (ORCPT ); Thu, 22 Oct 2020 08:44:35 -0400 Received: from mx2.suse.de ([195.135.220.15]:42412 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2506291AbgJVMof (ORCPT ); Thu, 22 Oct 2020 08:44:35 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 55E2EAC3F; Thu, 22 Oct 2020 12:44:34 +0000 (UTC) Date: Thu, 22 Oct 2020 14:44:32 +0200 From: Oscar Salvador To: Vlastimil Babka Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Michal Hocko , Pavel Tatashin , David Hildenbrand , Joonsoo Kim , Michal Hocko Subject: Re: [PATCH v2 6/7] mm, page_alloc: move draining pcplists to page isolation users Message-ID: <20201022124431.GD26121@linux> References: <20201008114201.18824-1-vbabka@suse.cz> <20201008114201.18824-7-vbabka@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201008114201.18824-7-vbabka@suse.cz> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 08, 2020 at 01:42:00PM +0200, Vlastimil Babka wrote: > Currently, pcplists are drained during set_migratetype_isolate() which means > once per pageblock processed start_isolate_page_range(). This is somewhat > wasteful. Moreover, the callers might need different guarantees, and the > draining is currently prone to races and does not guarantee that no page > from isolated pageblock will end up on the pcplist after the drain. > > Better guarantees are added by later patches and require explicit actions > by page isolation users that need them. Thus it makes sense to move the > current imperfect draining to the callers also as a preparation step. > > Suggested-by: David Hildenbrand > Suggested-by: Pavel Tatashin > Signed-off-by: Vlastimil Babka > Reviewed-by: David Hildenbrand > Acked-by: Michal Hocko Reviewed-by: Oscar Salvador -- Oscar Salvador SUSE L3