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 6EE93C433F5 for ; Mon, 13 Dec 2021 05:00:01 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C4FEC6B0071; Sun, 12 Dec 2021 23:59:50 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id C00876B0073; Sun, 12 Dec 2021 23:59:50 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AC86A6B0074; Sun, 12 Dec 2021 23:59:50 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0048.hostedemail.com [216.40.44.48]) by kanga.kvack.org (Postfix) with ESMTP id 9F2016B0071 for ; Sun, 12 Dec 2021 23:59:50 -0500 (EST) Received: from smtpin15.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 50BBA1809C04D for ; Mon, 13 Dec 2021 04:59:40 +0000 (UTC) X-FDA: 78911568120.15.28C2512 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by imf07.hostedemail.com (Postfix) with ESMTP id 9F84E40008 for ; Mon, 13 Dec 2021 04:59:39 +0000 (UTC) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 5DFB01F3B0; Mon, 13 Dec 2021 04:59:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1639371578; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=k2gChwyl/DClB5L/ZT8aeA5y8mUKecKjBiO/0QKY6kA=; b=EjXT775p7Ib4onLWPFpQRGtiEyslALZ9bZI7hc8yXChzHyJHZ9EjymDPHRmWnb3wI3EY1s vo9vutxlhmeMBMdUMMeEjbGVJWUQL5hb9PSTaFMoKMbuijj8cVdgI1cBNUzMjvcavizEkv dgBUeJhGUr9ykPpecP8Sbrk2A5kwuig= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1639371578; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=k2gChwyl/DClB5L/ZT8aeA5y8mUKecKjBiO/0QKY6kA=; b=hqsL0TIql1g+XAQIVqyCnbaG2whzR8D/uS62k89KHb57moD27i3si5uDxcmNGIU2IL6eAM U8UcCBivlGAfW0AA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 282D613AAF; Mon, 13 Dec 2021 04:59:33 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id N0DzNDXTtmGJSQAAMHmgww (envelope-from ); Mon, 13 Dec 2021 04:59:33 +0000 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 From: "NeilBrown" To: "Matthew Wilcox" Cc: "Andrew Morton" , "Mel Gorman" , "Philipp Reisner" , "Lars Ellenberg" , "Jan Kara" , "Ryusuke Konishi" , "Darrick J. Wong" , linux-xfs@vger.kernel.org, linux-ext4@vger.kernel.org, linux-nilfs@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] Remove inode_congested() In-reply-to: References: <163936868317.23860.5037433897004720387.stgit@noble.brown>, <163936886725.23860.2403757518009677424.stgit@noble.brown>, Date: Mon, 13 Dec 2021 15:59:30 +1100 Message-id: <163937157093.22433.10907067066589299028@noble.neil.brown.name> X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 9F84E40008 X-Stat-Signature: 6pynnseqpt8r359on3y3e55djpyy5rrt Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=EjXT775p; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=hqsL0TIq; spf=pass (imf07.hostedemail.com: domain of neilb@suse.de designates 195.135.220.29 as permitted sender) smtp.mailfrom=neilb@suse.de; dmarc=pass (policy=none) header.from=suse.de X-HE-Tag: 1639371579-695666 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, 13 Dec 2021, Matthew Wilcox wrote: > On Mon, Dec 13, 2021 at 03:14:27PM +1100, NeilBrown wrote: > > diff --git a/mm/vmscan.c b/mm/vmscan.c > > index fb9584641ac7..540aa0ea67ff 100644 > > --- a/mm/vmscan.c > > +++ b/mm/vmscan.c > > @@ -989,17 +989,6 @@ static inline int is_page_cache_freeable(struct page= *page) > > return page_count(page) - page_has_private(page) =3D=3D 1 + page_cache_= pins; > > } > > =20 > > -static int may_write_to_inode(struct inode *inode) > > -{ > > - if (current->flags & PF_SWAPWRITE) > > - return 1; > > - if (!inode_write_congested(inode)) > > - return 1; > > - if (inode_to_bdi(inode) =3D=3D current->backing_dev_info) > > - return 1; > > - return 0; > > -} >=20 > Why is it safe to get rid of the PF_SWAPWRITE and current->backing_dev_info > checks? Ask George Bool. If inode_write_congested() returns False, then may_write_to_inode() will always return True. NeilBrown >=20 > > @@ -1158,8 +1147,6 @@ static pageout_t pageout(struct page *page, struct = address_space *mapping) > > } > > if (mapping->a_ops->writepage =3D=3D NULL) > > return PAGE_ACTIVATE; > > - if (!may_write_to_inode(mapping->host)) > > - return PAGE_KEEP; > > =20 > > if (clear_page_dirty_for_io(page)) { > > int res; >=20 >=20