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 67FCFC433FE for ; Tue, 17 May 2022 23:58:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id D8C796B0072; Tue, 17 May 2022 19:58:58 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D3B7C6B0073; Tue, 17 May 2022 19:58:58 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C037B6B0074; Tue, 17 May 2022 19:58:58 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id ADE4F6B0072 for ; Tue, 17 May 2022 19:58:58 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 749E230EF8 for ; Tue, 17 May 2022 23:58:58 +0000 (UTC) X-FDA: 79476903156.15.EB40E85 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by imf13.hostedemail.com (Postfix) with ESMTP id D7A97200A3 for ; Tue, 17 May 2022 23:58:35 +0000 (UTC) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id B8326B81AB7; Tue, 17 May 2022 23:58:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 32E77C385B8; Tue, 17 May 2022 23:58:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1652831935; bh=Hi3SLGJSw+umom2b/a7ZHSBRqMcZS2fHfT6dXxjlDwQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=SzTmjKne7gDTvPDvUODt/tsTdkLXvjcyvkshYpnsfUmT4zexyQ5Zmpd4iTuAMH/uM sNhczWysegNmvcnGVoamaZxTyDFbd5/vv9a2VW5oOU5MSIXajUVtrqqOuGA1oL9uVV f1qd9e4JpM3sH3Yihnc44dW8PNRApap0EpjRRj9U= Date: Tue, 17 May 2022 16:58:54 -0700 From: Andrew Morton To: Minchan Kim Cc: Matthew Wilcox , LKML , linux-mm , Suren Baghdasaryan , Michal Hocko , John Dias , Tim Murray , Vladimir Davydov Subject: Re: [PATCH] mm: don't be stuck to rmap lock on reclaim path Message-Id: <20220517165854.fa6810576db304428b275385@linux-foundation.org> In-Reply-To: References: <20220503170341.1413961-1-minchan@kernel.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=SzTmjKne; spf=pass (imf13.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.68.75 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: D7A97200A3 X-Stat-Signature: spwyae7qpw6i5ts4gz3xcf5s5kj3bfsz X-HE-Tag: 1652831915-302319 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 Wed, 4 May 2022 23:11:04 -0700 Minchan Kim wrote: > > > + > > > + static struct rmap_walk_control rwc = { > > > .rmap_one = page_idle_clear_pte_refs_one, > > > .anon_lock = folio_lock_anon_vma_read, > > > }; > > So, delta is --- a/mm/page_idle.c~mm-dont-be-stuck-to-rmap-lock-on-reclaim-path-fix +++ a/mm/page_idle.c @@ -87,6 +87,10 @@ static void page_idle_clear_pte_refs(str { struct folio *folio = page_folio(page); + /* + * Since rwc.try_lock is unused, rwc is effectively immutable, so we + * can make it static to save some cycles and stack. + */ static struct rmap_walk_control rwc = { .rmap_one = page_idle_clear_pte_refs_one, .anon_lock = folio_lock_anon_vma_read, _ and with that, I believe this change is good to be imported into mm-stable later this week.