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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1E48AC433EF for ; Thu, 3 Mar 2022 22:41:46 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9FB048D0002; Thu, 3 Mar 2022 17:41:45 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 9AB3E8D0001; Thu, 3 Mar 2022 17:41:45 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 872B78D0002; Thu, 3 Mar 2022 17:41:45 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0173.hostedemail.com [216.40.44.173]) by kanga.kvack.org (Postfix) with ESMTP id 75F3D8D0001 for ; Thu, 3 Mar 2022 17:41:45 -0500 (EST) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 2D257181F1003 for ; Thu, 3 Mar 2022 22:41:45 +0000 (UTC) X-FDA: 79204548570.27.D600CB0 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf14.hostedemail.com (Postfix) with ESMTP id 6B2B9100008 for ; Thu, 3 Mar 2022 22:41:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=52IPoiZlULRFsRfp7a+MOcHPPK5OVaKArRJeKTkzhvo=; b=KRjqs5qByXCCtDLJuVi6CXCPEi Lpe0SgN11Y9rnKZhPft2uhbuREDPHnG+3PYR9R9faV5PJG2TCg9lOpWNOZHWAzJaT1lfLmOojK3xL 1P00Mu4GJnFpxvLRLiGHRJg1rmHpX3zEgakW1IWBZbdAnXP77Kp6GEI0XJGNfYbprut/I6tYMccVY R7AiMS81A4YWCTxb2MK1mCg6sLoiWcWzmYpvJiv+sagrOqn0TYMAIW8dpAC7qCWSThbsurU/ahF3P nSvw2sANT59tduACOlNAgWIVloDzRiiJPl2oDSOmqF6/3QLpFKZY5Epf3+UtBH2DVIFL2M4/PhNyt gHkqkyrw==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nPu8g-00C3LQ-Kt; Thu, 03 Mar 2022 22:41:38 +0000 Date: Thu, 3 Mar 2022 22:41:38 +0000 From: Matthew Wilcox To: Hugh Dickins Cc: David Hildenbrand , Andrew Morton , Nicholas Piggin , Yu Zhao , Yang Shi , Michal Hocko , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH mmotm] mm: delete __ClearPageWaiters() Message-ID: References: <351df0af-78f2-c20-2a6d-e5f978e5ca1@google.com> <9dda55d5-eafa-3177-2a4c-32ccb7e146e3@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9dda55d5-eafa-3177-2a4c-32ccb7e146e3@google.com> X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 6B2B9100008 X-Stat-Signature: 3pwmx1uorm3qo58wugesb3aup6mosnkw Authentication-Results: imf14.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=KRjqs5qB; spf=none (imf14.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none X-HE-Tag: 1646347304-340968 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 Thu, Mar 03, 2022 at 02:28:46PM -0800, Hugh Dickins wrote: > On Thu, 3 Mar 2022, David Hildenbrand wrote: > > On 03.03.22 02:56, Hugh Dickins wrote: > > > The PG_waiters bit is not included in PAGE_FLAGS_CHECK_AT_FREE, and > > > vmscan.c's free_unref_page_list() callers rely on that not to generate > > > bad_page() alerts. So __page_cache_release() and release_pages() (and > > > the presumably copy-and-pasted put_zone_device_private_or_public_page()) > > Hah, I'm showing my age there, or the patch's age: it's been rebranded > frequently since then, with linux-next calling it free_zone_device_page(), > as you kindly point out. How long before it's free_zone_device_folio()? Probably not a serious question, but within the next year, I expect. I have a prototype patch to do the entire page freeing path, but it wasn't a priority for this merge window.