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=-5.8 required=3.0 tests=BAYES_00,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 6E69AC433DB for ; Wed, 24 Mar 2021 08:37:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31FA3619EC for ; Wed, 24 Mar 2021 08:37:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233900AbhCXIgf (ORCPT ); Wed, 24 Mar 2021 04:36:35 -0400 Received: from mx2.suse.de ([195.135.220.15]:39418 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230368AbhCXIg1 (ORCPT ); Wed, 24 Mar 2021 04:36:27 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1616574981; h=from:from:reply-to: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=Mt21mzndWXnoKj4VEg4Qe8nZIASbLqeRQGWJ6Q9oDrk=; b=sr7h+ok4LZNJXBiqpPlUhNKwnC5jT9zVd+NpJX3fysewOyKvA8Z1AtV1P7iMzP1xzs2/cI 2Khivmn/kTad78NGlzjLvA4nYkvo4sSpSMXIOLe0VpfVHyd8cLVQTGFNH2UXJaNFuRg8kJ qL31d3LDsokJnpodB9pzK+XI9j7pVS4= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 1E16DAB9B; Wed, 24 Mar 2021 08:36:21 +0000 (UTC) Date: Wed, 24 Mar 2021 09:36:19 +0100 From: Michal Hocko To: Mike Kravetz Cc: Peter Zijlstra , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Shakeel Butt , Oscar Salvador , David Hildenbrand , Muchun Song , David Rientjes , Miaohe Lin , Matthew Wilcox , HORIGUCHI NAOYA , "Aneesh Kumar K . V" , Waiman Long , Peter Xu , Mina Almasry , Andrew Morton Subject: Re: [RFC PATCH 2/8] hugetlb: recompute min_count when dropping hugetlb_lock Message-ID: References: <20210319224209.150047-1-mike.kravetz@oracle.com> <20210319224209.150047-3-mike.kravetz@oracle.com> <52db15d1-4ed1-6c3c-b638-6efdccf6e62e@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <52db15d1-4ed1-6c3c-b638-6efdccf6e62e@oracle.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 23-03-21 16:18:08, Mike Kravetz wrote: [...] > Here is another thought. > In patch 5 you suggest removing all pages from hugetlb with the lock > held, and adding them to a list. Then, drop the lock and free all > pages on the list. If we do this, then the value computed here (min_count) > can not change while we are looping. So, this patch would be unnecessary. > That is another argument in favor of batching the frees. > > Unless there is something wrong in my thinking, I am going to take that > approach and drop this patch. Makes sense -- Michal Hocko SUSE Labs