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 9AFCEC433C1 for ; Mon, 22 Mar 2021 14:46:35 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E765B6192B for ; Mon, 22 Mar 2021 14:46:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E765B6192B Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id BC3806B00AC; Mon, 22 Mar 2021 10:27:43 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B71806B00CE; Mon, 22 Mar 2021 10:27:43 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A13D66B00CF; Mon, 22 Mar 2021 10:27:43 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0036.hostedemail.com [216.40.44.36]) by kanga.kvack.org (Postfix) with ESMTP id 7FF2E6B00AC for ; Mon, 22 Mar 2021 10:27:43 -0400 (EDT) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id CB1E5585C for ; Mon, 22 Mar 2021 14:46:33 +0000 (UTC) X-FDA: 77947786266.24.D653C57 Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf24.hostedemail.com (Postfix) with ESMTP id 85960A0009E3 for ; Mon, 22 Mar 2021 14:46:27 +0000 (UTC) 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=1616424386; 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=Icvrunq7s47g5UuOx3C1ykL1/UQNOPaopN5BLnKRXPs=; b=kmtnnvMkJ8AWU2nH5OpmmbR+C/wd6mZIE+1qW7VfAkrjeffS1DtbbwRtgNc/msHHnaFcoI JAjpo8Tt2kccfF+GHA/8PToU4TLpURCzaSIwT/Fc3LzteK7qXCvlMaEbbWFIIAGMxRLstT dToveiO9mjjsJTGvlsxIMzds5dOWeoQ= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 462A5ACFC; Mon, 22 Mar 2021 14:46:26 +0000 (UTC) Date: Mon, 22 Mar 2021 15:46:25 +0100 From: Michal Hocko To: Mike Kravetz Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Shakeel Butt , Oscar Salvador , David Hildenbrand , Muchun Song , David Rientjes , Miaohe Lin , Peter Zijlstra , Matthew Wilcox , HORIGUCHI NAOYA , "Aneesh Kumar K . V" , Waiman Long , Peter Xu , Mina Almasry , Andrew Morton Subject: Re: [RFC PATCH 7/8] hugetlb: add update_and_free_page_no_sleep for irq context Message-ID: References: <20210319224209.150047-1-mike.kravetz@oracle.com> <20210319224209.150047-8-mike.kravetz@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 85960A0009E3 X-Stat-Signature: je9kez9uatofkoyz85y4kdprnc6985ht Received-SPF: none (suse.com>: No applicable sender policy available) receiver=imf24; identity=mailfrom; envelope-from=""; helo=mx2.suse.de; client-ip=195.135.220.15 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616424387-813570 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon 22-03-21 15:42:27, Michal Hocko wrote: [...] > Besides that the changelog doesn't really say anything about changed > user visible behavior change. Now if somebody decreases the GB huge pool > from the userspace the real effect on the freed up memory will be > postponed to some later time. That "later" is unpredictable as it > depends on WQ utilization. We definitely need some sort of > wait_for_inflight pages. One way to do that would be to have a dedicated > WQ and schedule a sync work item after the pool has been shrunk and wait > for that item. Scratch that. It is not really clear from the patch context but after looking at the resulting code set_max_huge_pages will use the blockable update_and_free_page so we should be fine. Sorry about the noise! -- Michal Hocko SUSE Labs