From patchwork Thu Sep 2 21:59:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 12473199 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 BBD50C433FE for ; Thu, 2 Sep 2021 21:59:29 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 75CF860F12 for ; Thu, 2 Sep 2021 21:59:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 75CF860F12 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 1214994000B; Thu, 2 Sep 2021 17:59:29 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0AA8A6B0186; Thu, 2 Sep 2021 17:59:29 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E8CE794000B; Thu, 2 Sep 2021 17:59:28 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0033.hostedemail.com [216.40.44.33]) by kanga.kvack.org (Postfix) with ESMTP id D48386B0185 for ; Thu, 2 Sep 2021 17:59:28 -0400 (EDT) Received: from smtpin19.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 9810182F74B2 for ; Thu, 2 Sep 2021 21:59:28 +0000 (UTC) X-FDA: 78544000416.19.2558A37 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf15.hostedemail.com (Postfix) with ESMTP id 46247D000097 for ; Thu, 2 Sep 2021 21:59:28 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 0E7AF610A0; Thu, 2 Sep 2021 21:59:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1630619967; bh=xZpfLR+VnBCQKxkYuFG8+N2iHusfIyCWON8e/grx0a8=; h=Date:From:To:Subject:In-Reply-To:From; b=vP7RDfsWqut26XtKWEMiRUYrE8MACUEl/W3/2R98K3Mn+qkacw0AYf4Zr7Sxi0TsJ znVEQvuu1b1LixFFJxbgQe/5edFh5w6gh1WtMUfR8KCgtW3nFvnwJEIdlvwfGKfuqi e5qGQTJXKWgPkc8UagpfQrDsAMtbi9p6Gts362DI= Date: Thu, 02 Sep 2021 14:59:26 -0700 From: Andrew Morton To: akpm@linux-foundation.org, dan.j.williams@intel.com, dave.hansen@linux.intel.com, david@redhat.com, gthelen@google.com, kbusch@kernel.org, linux-mm@kvack.org, mhocko@suse.com, mm-commits@vger.kernel.org, osalvador@suse.de, rientjes@google.com, shy828301@gmail.com, torvalds@linux-foundation.org, weixugc@google.com, yang.shi@linux.alibaba.com, ying.huang@intel.com, ziy@nvidia.com Subject: [patch 179/212] mm/vmscan: Consider anonymous pages without swap Message-ID: <20210902215926.S9pXb3J9c%akpm@linux-foundation.org> In-Reply-To: <20210902144820.78957dff93d7bea620d55a89@linux-foundation.org> User-Agent: s-nail v14.8.16 Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=vP7RDfsW; dmarc=none; spf=pass (imf15.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 46247D000097 X-Stat-Signature: u9w5iwesabthp4koepg5qcsj6ghstk5e X-HE-Tag: 1630619968-146804 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: From: Keith Busch Subject: mm/vmscan: Consider anonymous pages without swap Reclaim anonymous pages if a migration path is available now that demotion provides a non-swap recourse for reclaiming anon pages. Note that this check is subtly different from the can_age_anon_pages() checks. This mechanism checks whether a specific page in a specific context can actually be reclaimed, given current swap space and cgroup limits. can_age_anon_pages() is a much simpler and more preliminary check which just says whether there is a possibility of future reclaim. [kbusch@kernel.org: v11] Link: https://lkml.kernel.org/r/20210715055145.195411-8-ying.huang@intel.com Link: https://lkml.kernel.org/r/20210721063926.3024591-7-ying.huang@intel.com Link: https://lkml.kernel.org/r/20210715055145.195411-8-ying.huang@intel.com Cc: Keith Busch Signed-off-by: Dave Hansen Signed-off-by: "Huang, Ying" Reviewed-by: Yang Shi Reviewed-by: Zi Yan Cc: Michal Hocko Cc: Wei Xu Cc: David Rientjes Cc: Dan Williams Cc: David Hildenbrand Cc: Greg Thelen Cc: Oscar Salvador Cc: Yang Shi Signed-off-by: Andrew Morton --- mm/vmscan.c | 34 ++++++++++++++++++++++++++++++---- 1 file changed, 30 insertions(+), 4 deletions(-) --- a/mm/vmscan.c~mm-vmscan-consider-anonymous-pages-without-swap +++ a/mm/vmscan.c @@ -524,7 +524,7 @@ static long add_nr_deferred(long nr, str static bool can_demote(int nid, struct scan_control *sc) { - if (sc->no_demotion) + if (sc && sc->no_demotion) return false; if (next_demotion_node(nid) == NUMA_NO_NODE) return false; @@ -533,6 +533,31 @@ static bool can_demote(int nid, struct s return false; } +static inline bool can_reclaim_anon_pages(struct mem_cgroup *memcg, + int nid, + struct scan_control *sc) +{ + if (memcg == NULL) { + /* + * For non-memcg reclaim, is there + * space in any swap device? + */ + if (get_nr_swap_pages() > 0) + return true; + } else { + /* Is the memcg below its swap limit? */ + if (mem_cgroup_get_nr_swap_pages(memcg) > 0) + return true; + } + + /* + * The page can not be swapped. + * + * Can it be reclaimed from this node via demotion? + */ + return can_demote(nid, sc); +} + /* * This misses isolated pages which are not accounted for to save counters. * As the data only determines if reclaim or compaction continues, it is @@ -544,7 +569,7 @@ unsigned long zone_reclaimable_pages(str nr = zone_page_state_snapshot(zone, NR_ZONE_INACTIVE_FILE) + zone_page_state_snapshot(zone, NR_ZONE_ACTIVE_FILE); - if (get_nr_swap_pages() > 0) + if (can_reclaim_anon_pages(NULL, zone_to_nid(zone), NULL)) nr += zone_page_state_snapshot(zone, NR_ZONE_INACTIVE_ANON) + zone_page_state_snapshot(zone, NR_ZONE_ACTIVE_ANON); @@ -2541,6 +2566,7 @@ enum scan_balance { static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, unsigned long *nr) { + struct pglist_data *pgdat = lruvec_pgdat(lruvec); struct mem_cgroup *memcg = lruvec_memcg(lruvec); unsigned long anon_cost, file_cost, total_cost; int swappiness = mem_cgroup_swappiness(memcg); @@ -2551,7 +2577,7 @@ static void get_scan_count(struct lruvec enum lru_list lru; /* If we have no swap space, do not bother scanning anon pages. */ - if (!sc->may_swap || mem_cgroup_get_nr_swap_pages(memcg) <= 0) { + if (!sc->may_swap || !can_reclaim_anon_pages(memcg, pgdat->node_id, sc)) { scan_balance = SCAN_FILE; goto out; } @@ -2929,7 +2955,7 @@ static inline bool should_continue_recla */ pages_for_compaction = compact_gap(sc->order); inactive_lru_pages = node_page_state(pgdat, NR_INACTIVE_FILE); - if (get_nr_swap_pages() > 0) + if (can_reclaim_anon_pages(NULL, pgdat->node_id, sc)) inactive_lru_pages += node_page_state(pgdat, NR_INACTIVE_ANON); return inactive_lru_pages > pages_for_compaction;