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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 D927FC1B08C for ; Thu, 15 Jul 2021 05:52:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C513261358 for ; Thu, 15 Jul 2021 05:52:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240090AbhGOFzc (ORCPT ); Thu, 15 Jul 2021 01:55:32 -0400 Received: from mga02.intel.com ([134.134.136.20]:22887 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240073AbhGOFz2 (ORCPT ); Thu, 15 Jul 2021 01:55:28 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10045"; a="197661966" X-IronPort-AV: E=Sophos;i="5.84,240,1620716400"; d="scan'208";a="197661966" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2021 22:52:36 -0700 X-IronPort-AV: E=Sophos;i="5.84,240,1620716400"; d="scan'208";a="505591642" Received: from yhuang6-mobl1.sh.intel.com ([10.238.6.138]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2021 22:52:33 -0700 From: Huang Ying To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Keith Busch , Dave Hansen , "Huang, Ying" , Yang Shi , Michal Hocko , Zi Yan , Wei Xu , David Rientjes , Dan Williams , David Hildenbrand Subject: [PATCH -V10 7/9] mm/vmscan: Consider anonymous pages without swap Date: Thu, 15 Jul 2021 13:51:43 +0800 Message-Id: <20210715055145.195411-8-ying.huang@intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210715055145.195411-1-ying.huang@intel.com> References: <20210715055145.195411-1-ying.huang@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Keith Busch 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. Cc: Keith Busch Signed-off-by: Dave Hansen Signed-off-by: "Huang, Ying" Reviewed-by: Yang Shi Cc: Michal Hocko Cc: Zi Yan Cc: Wei Xu Cc: David Rientjes Cc: Dan Williams Cc: David Hildenbrand -- Changes since 20210618: * Consider whether demotion is disabled Changes from Dave 202010: * remove 'total_swap_pages' modification Changes from Dave 202006: * rename reclaim_anon_pages()->can_reclaim_anon_pages() Note: Keith's Intel SoB is commented out because he is no longer at Intel and his @intel.com mail will bounce. --- mm/vmscan.c | 34 ++++++++++++++++++++++++++++++---- 1 file changed, 30 insertions(+), 4 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index 302f8d6e7b65..0f9be998230f 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -521,7 +521,7 @@ static long add_nr_deferred(long nr, struct shrinker *shrinker, static bool can_demote_anon_pages(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; @@ -530,6 +530,31 @@ static bool can_demote_anon_pages(int nid, struct scan_control *sc) 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_anon_pages(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 @@ -541,7 +566,7 @@ unsigned long zone_reclaimable_pages(struct zone *zone) 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); @@ -2539,6 +2564,7 @@ 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); @@ -2549,7 +2575,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, 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; } @@ -2919,7 +2945,7 @@ static inline bool should_continue_reclaim(struct pglist_data *pgdat, */ 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; -- 2.30.2