From patchwork Fri Jun 18 06:15:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Huang, Ying" X-Patchwork-Id: 12330239 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,URIBL_BLOCKED,USER_AGENT_GIT 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 24FB3C48BDF for ; Fri, 18 Jun 2021 06:16:24 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C516361260 for ; Fri, 18 Jun 2021 06:16:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C516361260 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A86666B0075; Fri, 18 Jun 2021 02:16:22 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A0EE16B0078; Fri, 18 Jun 2021 02:16:22 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 862136B007B; Fri, 18 Jun 2021 02:16:22 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0002.hostedemail.com [216.40.44.2]) by kanga.kvack.org (Postfix) with ESMTP id 435B96B0075 for ; Fri, 18 Jun 2021 02:16:22 -0400 (EDT) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id E180BD220 for ; Fri, 18 Jun 2021 06:16:21 +0000 (UTC) X-FDA: 78265834962.26.F53E570 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by imf23.hostedemail.com (Postfix) with ESMTP id 1392BA0009EC for ; Fri, 18 Jun 2021 06:16:20 +0000 (UTC) IronPort-SDR: ahF+Phdi9fObcU5PjrfixBvE+p0p09uxIS8ZAHI1PrJQsVOE/GsCAglNJF2y2cHdqPxS79Nc6d rXQhLapBFoOw== X-IronPort-AV: E=McAfee;i="6200,9189,10018"; a="228027474" X-IronPort-AV: E=Sophos;i="5.83,283,1616482800"; d="scan'208";a="228027474" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Jun 2021 23:16:20 -0700 IronPort-SDR: wAbcD0UxpsM1FKmAJjPQKKewDBOlWHpo5wAHmYwsaVrEUrUy7jYcx+3i23NmDyfuMPtcZyp2j4 HD7v2QVc9Bcg== X-IronPort-AV: E=Sophos;i="5.83,283,1616482800"; d="scan'208";a="485573657" Received: from mzhou6-mobl1.ccr.corp.intel.com (HELO yhuang6-mobl1.ccr.corp.intel.com) ([10.254.212.155]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Jun 2021 23:16:17 -0700 From: Huang Ying To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Dave Hansen , "Huang, Ying" , Michal Hocko , Wei Xu , Yang Shi , David Rientjes , Dan Williams , osalvador Subject: [PATCH -V8 05/10] mm/migrate: demote pages during reclaim Date: Fri, 18 Jun 2021 14:15:32 +0800 Message-Id: <20210618061537.434999-6-ying.huang@intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210618061537.434999-1-ying.huang@intel.com> References: <20210618061537.434999-1-ying.huang@intel.com> MIME-Version: 1.0 Authentication-Results: imf23.hostedemail.com; dkim=none; spf=none (imf23.hostedemail.com: domain of ying.huang@intel.com has no SPF policy when checking 192.55.52.88) smtp.mailfrom=ying.huang@intel.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none) X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 1392BA0009EC X-Stat-Signature: sgkwzdezoi6wcsepsakai9nhf8poawim X-HE-Tag: 1623996980-557307 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: Dave Hansen This is mostly derived from a patch from Yang Shi: https://lore.kernel.org/linux-mm/1560468577-101178-10-git-send-email-yang.shi@linux.alibaba.com/ Add code to the reclaim path (shrink_page_list()) to "demote" data to another NUMA node instead of discarding the data. This always avoids the cost of I/O needed to read the page back in and sometimes avoids the writeout cost when the pagee is dirty. A second pass through shrink_page_list() will be made if any demotions fail. This essentally falls back to normal reclaim behavior in the case that demotions fail. Previous versions of this patch may have simply failed to reclaim pages which were eligible for demotion but were unable to be demoted in practice. Note: This just adds the start of infratructure for migration. It is actually disabled next to the FIXME in migrate_demote_page_ok(). Signed-off-by: Dave Hansen Signed-off-by: "Huang, Ying" Cc: Michal Hocko Cc: Wei Xu Cc: Yang Shi Cc: David Rientjes Cc: Dan Williams Cc: osalvador --- changes from 20210122: * move from GFP_HIGHUSER -> GFP_HIGHUSER_MOVABLE (Ying) changes from 202010: * add MR_NUMA_MISPLACED to trace MIGRATE_REASON define * make migrate_demote_page_ok() static, remove 'sc' arg until later patch * remove unnecessary alloc_demote_page() hugetlb warning * Simplify alloc_demote_page() gfp mask. Depend on __GFP_NORETRY to make it lightweight instead of fancier stuff like leaving out __GFP_IO/FS. * Allocate migration page with alloc_migration_target() instead of allocating directly. changes from 20200730: * Add another pass through shrink_page_list() when demotion fails. changes from 20210302: * Use __GFP_THISNODE and revise the comment explaining the GFP mask constructionn --- include/linux/migrate.h | 9 ++++ include/trace/events/migrate.h | 3 +- mm/vmscan.c | 83 ++++++++++++++++++++++++++++++++++ 3 files changed, 94 insertions(+), 1 deletion(-) diff --git a/include/linux/migrate.h b/include/linux/migrate.h index 4a49bb358787..42952cbe452b 100644 --- a/include/linux/migrate.h +++ b/include/linux/migrate.h @@ -28,6 +28,7 @@ enum migrate_reason { MR_NUMA_MISPLACED, MR_CONTIG_RANGE, MR_LONGTERM_PIN, + MR_DEMOTION, MR_TYPES }; @@ -191,6 +192,14 @@ struct migrate_vma { int migrate_vma_setup(struct migrate_vma *args); void migrate_vma_pages(struct migrate_vma *migrate); void migrate_vma_finalize(struct migrate_vma *migrate); +int next_demotion_node(int node); + +#else /* CONFIG_MIGRATION disabled: */ + +static inline int next_demotion_node(int node) +{ + return NUMA_NO_NODE; +} #endif /* CONFIG_MIGRATION */ diff --git a/include/trace/events/migrate.h b/include/trace/events/migrate.h index 9fb2a3bbcdfb..779f3fad9ecd 100644 --- a/include/trace/events/migrate.h +++ b/include/trace/events/migrate.h @@ -21,7 +21,8 @@ EM( MR_MEMPOLICY_MBIND, "mempolicy_mbind") \ EM( MR_NUMA_MISPLACED, "numa_misplaced") \ EM( MR_CONTIG_RANGE, "contig_range") \ - EMe(MR_LONGTERM_PIN, "longterm_pin") + EM( MR_LONGTERM_PIN, "longterm_pin") \ + EMe(MR_DEMOTION, "demotion") /* * First define the enums in the above macros to be exported to userspace diff --git a/mm/vmscan.c b/mm/vmscan.c index 5199b9696bab..ddda32031f0c 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -41,6 +41,7 @@ #include #include #include +#include #include #include #include @@ -1231,6 +1232,23 @@ static enum page_references page_check_references(struct page *page, return PAGEREF_RECLAIM; } +static bool migrate_demote_page_ok(struct page *page) +{ + int next_nid = next_demotion_node(page_to_nid(page)); + + VM_BUG_ON_PAGE(!PageLocked(page), page); + VM_BUG_ON_PAGE(PageHuge(page), page); + VM_BUG_ON_PAGE(PageLRU(page), page); + + if (next_nid == NUMA_NO_NODE) + return false; + if (PageTransHuge(page) && !thp_migration_supported()) + return false; + + // FIXME: actually enable this later in the series + return false; +} + /* Check if a page is dirty or under writeback */ static void page_check_dirty_writeback(struct page *page, bool *dirty, bool *writeback) @@ -1261,6 +1279,47 @@ static void page_check_dirty_writeback(struct page *page, mapping->a_ops->is_dirty_writeback(page, dirty, writeback); } +static struct page *alloc_demote_page(struct page *page, unsigned long node) +{ + struct migration_target_control mtc = { + /* + * Allocate from 'node', or fail the quickly and quietly. + * When this happens, 'page; will likely just be discarded + * instead of migrated. + */ + .gfp_mask = (GFP_HIGHUSER_MOVABLE & ~__GFP_RECLAIM) | + __GFP_THISNODE | __GFP_NOWARN | + __GFP_NOMEMALLOC | GFP_NOWAIT, + .nid = node + }; + + return alloc_migration_target(page, (unsigned long)&mtc); +} + +/* + * Take pages on @demote_list and attempt to demote them to + * another node. Pages which are not demoted are left on + * @demote_pages. + */ +static unsigned int demote_page_list(struct list_head *demote_pages, + struct pglist_data *pgdat, + struct scan_control *sc) +{ + int target_nid = next_demotion_node(pgdat->node_id); + unsigned int nr_succeeded = 0; + int err; + + if (list_empty(demote_pages)) + return 0; + + /* Demotion ignores all cpuset and mempolicy settings */ + err = migrate_pages(demote_pages, alloc_demote_page, NULL, + target_nid, MIGRATE_ASYNC, MR_DEMOTION, + &nr_succeeded); + + return nr_succeeded; +} + /* * shrink_page_list() returns the number of reclaimed pages */ @@ -1272,12 +1331,15 @@ static unsigned int shrink_page_list(struct list_head *page_list, { LIST_HEAD(ret_pages); LIST_HEAD(free_pages); + LIST_HEAD(demote_pages); unsigned int nr_reclaimed = 0; unsigned int pgactivate = 0; + bool do_demote_pass = true; memset(stat, 0, sizeof(*stat)); cond_resched(); +retry: while (!list_empty(page_list)) { struct address_space *mapping; struct page *page; @@ -1426,6 +1488,16 @@ static unsigned int shrink_page_list(struct list_head *page_list, ; /* try to reclaim the page below */ } + /* + * Before reclaiming the page, try to relocate + * its contents to another node. + */ + if (do_demote_pass && migrate_demote_page_ok(page)) { + list_add(&page->lru, &demote_pages); + unlock_page(page); + continue; + } + /* * Anonymous process memory has backing store? * Try to allocate it some swap space here. @@ -1676,6 +1748,17 @@ static unsigned int shrink_page_list(struct list_head *page_list, list_add(&page->lru, &ret_pages); VM_BUG_ON_PAGE(PageLRU(page) || PageUnevictable(page), page); } + /* 'page_list' is always empty here */ + + /* Migrate pages selected for demotion */ + nr_reclaimed += demote_page_list(&demote_pages, pgdat, sc); + /* Pages that could not be demoted are still in @demote_pages */ + if (!list_empty(&demote_pages)) { + /* Pages which failed to demoted go back on @page_list for retry: */ + list_splice_init(&demote_pages, page_list); + do_demote_pass = false; + goto retry; + } pgactivate = stat->nr_activate[0] + stat->nr_activate[1];