From patchwork Tue Aug 25 00:23:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Huang, Ying" X-Patchwork-Id: 11734495 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BDB43913 for ; Tue, 25 Aug 2020 00:24:44 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 889562074D for ; Tue, 25 Aug 2020 00:24:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 889562074D 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 567E26B0022; Mon, 24 Aug 2020 20:24:43 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 518636B0023; Mon, 24 Aug 2020 20:24:43 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 40AFF8D0003; Mon, 24 Aug 2020 20:24:43 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0102.hostedemail.com [216.40.44.102]) by kanga.kvack.org (Postfix) with ESMTP id 259E76B0022 for ; Mon, 24 Aug 2020 20:24:43 -0400 (EDT) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id DF5E6180AD815 for ; Tue, 25 Aug 2020 00:24:42 +0000 (UTC) X-FDA: 77187195204.07.fowl60_4f1137727057 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin07.hostedemail.com (Postfix) with ESMTP id BA1511803F9AA for ; Tue, 25 Aug 2020 00:24:42 +0000 (UTC) X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,ying.huang@intel.com,,RULES_HIT:30045:30051:30054:30064:30070:30074:30090,0,RBL:134.134.136.20:@intel.com:.lbl8.mailshell.net-62.50.0.100 64.95.201.95;04ygu33cf58nq5shuwanisr86om3eock8ptsod9sqyt11zw4nzk7jdhfo6uferm.imubx8xgz58j551jtun5gi1bikybfkbexzi631he1s96syj3q7orwjkhteizmho.r-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:ft,MSBL:0,DNSBL:none,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: fowl60_4f1137727057 X-Filterd-Recvd-Size: 12111 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by imf07.hostedemail.com (Postfix) with ESMTP for ; Tue, 25 Aug 2020 00:24:41 +0000 (UTC) IronPort-SDR: s1s3WlXvoIutdHxvgRgZVt8/p6eYA3hsCY5P/yPz+M0M/v55ARV8U4jiYToPrOydRbNYhC4qz5 r6mSP8C4Fg3A== X-IronPort-AV: E=McAfee;i="6000,8403,9723"; a="143794286" X-IronPort-AV: E=Sophos;i="5.76,350,1592895600"; d="scan'208";a="143794286" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Aug 2020 17:24:41 -0700 IronPort-SDR: EDUiDsY5vD0yVv7yxAOaUPQeqP6sM8sTgqKY0a4u3eotGwg9AsRqjkBEUax+21fAbBlIFLsyyx 3y/GocM9V0fw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.76,350,1592895600"; d="scan'208";a="443428043" Received: from huiyao-mobl2.ccr.corp.intel.com (HELO yhuang-mobile.ccr.corp.intel.com) ([10.254.214.197]) by orsmga004.jf.intel.com with ESMTP; 24 Aug 2020 17:24:36 -0700 From: Huang Ying To: Peter Zijlstra Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Andrew Morton , Michal Hocko , Rik van Riel , Mel Gorman , Ingo Molnar , Dave Hansen , Dan Williams Subject: [RFC -V3 1/5] autonuma: Optimize page placement for memory tiering system Date: Tue, 25 Aug 2020 08:23:50 +0800 Message-Id: <20200825002354.17038-2-ying.huang@intel.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200825002354.17038-1-ying.huang@intel.com> References: <20200825002354.17038-1-ying.huang@intel.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: BA1511803F9AA X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam05 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: With the advent of various new memory types, some machines will have multiple types of memory, e.g. DRAM and PMEM (persistent memory). The memory subsystem of these machines can be called memory tiering system, because the performance of the different types of memory are usually different. In such system, because of the memory accessing pattern changing etc, some pages in the slow memory may become hot globally. So in this patch, the AutoNUMA mechanism is enhanced to optimize the page placement among the different memory types according to hot/cold dynamically. In a typical memory tiering system, there are CPUs, fast memory and slow memory in each physical NUMA node. The CPUs and the fast memory will be put in one logical node (called fast memory node), while the slow memory will be put in another (faked) logical node (called slow memory node). That is, the fast memory is regarded as local while the slow memory is regarded as remote. So it's possible for the recently accessed pages in the slow memory node to be promoted to the fast memory node via the existing AutoNUMA mechanism. The original AutoNUMA mechanism will stop to migrate pages if the free memory of the target node will become below the high watermark. This is a reasonable policy if there's only one memory type. But this makes the original AutoNUMA mechanism almost not work to optimize page placement among different memory types. Details are as follows. It's the common cases that the working-set size of the workload is larger than the size of the fast memory nodes. Otherwise, it's unnecessary to use the slow memory at all. So in the common cases, there are almost always no enough free pages in the fast memory nodes, so that the globally hot pages in the slow memory node cannot be promoted to the fast memory node. To solve the issue, we have 2 choices as follows, a. Ignore the free pages watermark checking when promoting hot pages from the slow memory node to the fast memory node. This will create some memory pressure in the fast memory node, thus trigger the memory reclaiming. So that, the cold pages in the fast memory node will be demoted to the slow memory node. b. Make kswapd of the fast memory node to reclaim pages until the free pages are a little more (about 10MB) than the high watermark. Then, if the free pages of the fast memory node reaches high watermark, and some hot pages need to be promoted, kswapd of the fast memory node will be waken up to demote some cold pages in the fast memory node to the slow memory node. This will free some extra space in the fast memory node, so the hot pages in the slow memory node can be promoted to the fast memory node. The choice "a" will create the memory pressure in the fast memory node. If the memory pressure of the workload is high, the memory pressure may become so high that the memory allocation latency of the workload is influenced, e.g. the direct reclaiming may be triggered. The choice "b" works much better at this aspect. If the memory pressure of the workload is high, the hot pages promotion will stop earlier because its allocation watermark is higher than that of the normal memory allocation. So in this patch, choice "b" is implemented. In addition to the original page placement optimization among sockets, the AutoNUMA mechanism is extended to be used to optimize page placement according to hot/cold among different memory types. So the sysctl user space interface (numa_balancing) is extended in a backward compatible way as follow, so that the users can enable/disable these functionality individually. The sysctl is converted from a Boolean value to a bits field. The definition of the flags is, - 0x0: NUMA_BALANCING_DISABLED - 0x1: NUMA_BALANCING_NORMAL - 0x2: NUMA_BALANCING_MEMORY_TIERING TODO: - Update ABI document: Documentation/sysctl/kernel.txt Signed-off-by: "Huang, Ying" Cc: Andrew Morton Cc: Michal Hocko Cc: Rik van Riel Cc: Mel Gorman Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Dave Hansen Cc: Dan Williams Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org --- include/linux/sched/sysctl.h | 5 +++++ kernel/sched/core.c | 9 +++------ kernel/sysctl.c | 7 ++++--- mm/migrate.c | 30 +++++++++++++++++++++++++++--- mm/vmscan.c | 15 +++++++++++++++ 5 files changed, 54 insertions(+), 12 deletions(-) diff --git a/include/linux/sched/sysctl.h b/include/linux/sched/sysctl.h index 660ac49f2b53..bdd38045d14c 100644 --- a/include/linux/sched/sysctl.h +++ b/include/linux/sched/sysctl.h @@ -39,6 +39,11 @@ enum sched_tunable_scaling { }; extern enum sched_tunable_scaling sysctl_sched_tunable_scaling; +#define NUMA_BALANCING_DISABLED 0x0 +#define NUMA_BALANCING_NORMAL 0x1 +#define NUMA_BALANCING_MEMORY_TIERING 0x2 + +extern int sysctl_numa_balancing_mode; extern unsigned int sysctl_numa_balancing_scan_delay; extern unsigned int sysctl_numa_balancing_scan_period_min; extern unsigned int sysctl_numa_balancing_scan_period_max; diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 2142c6767682..dfbcd684fa40 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2794,6 +2794,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p) } DEFINE_STATIC_KEY_FALSE(sched_numa_balancing); +int sysctl_numa_balancing_mode; #ifdef CONFIG_NUMA_BALANCING @@ -2809,20 +2810,16 @@ void set_numabalancing_state(bool enabled) int sysctl_numa_balancing(struct ctl_table *table, int write, void *buffer, size_t *lenp, loff_t *ppos) { - struct ctl_table t; int err; - int state = static_branch_likely(&sched_numa_balancing); if (write && !capable(CAP_SYS_ADMIN)) return -EPERM; - t = *table; - t.data = &state; - err = proc_dointvec_minmax(&t, write, buffer, lenp, ppos); + err = proc_dointvec_minmax(table, write, buffer, lenp, ppos); if (err < 0) return err; if (write) - set_numabalancing_state(state); + set_numabalancing_state(*(int *)table->data); return err; } #endif diff --git a/kernel/sysctl.c b/kernel/sysctl.c index db1ce7af2563..75a6d35bd22e 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -113,6 +113,7 @@ static int sixty = 60; static int __maybe_unused neg_one = -1; static int __maybe_unused two = 2; +static int __maybe_unused three = 3; static int __maybe_unused four = 4; static unsigned long zero_ul; static unsigned long one_ul = 1; @@ -1756,12 +1757,12 @@ static struct ctl_table kern_table[] = { }, { .procname = "numa_balancing", - .data = NULL, /* filled in by handler */ - .maxlen = sizeof(unsigned int), + .data = &sysctl_numa_balancing_mode, + .maxlen = sizeof(int), .mode = 0644, .proc_handler = sysctl_numa_balancing, .extra1 = SYSCTL_ZERO, - .extra2 = SYSCTL_ONE, + .extra2 = &three, }, #endif /* CONFIG_NUMA_BALANCING */ #endif /* CONFIG_SCHED_DEBUG */ diff --git a/mm/migrate.c b/mm/migrate.c index 11e10e72cf92..9c5aa588ea4f 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -50,6 +50,7 @@ #include #include #include +#include #include @@ -1954,13 +1955,36 @@ static struct page *alloc_misplaced_dst_page(struct page *page, static int numamigrate_isolate_page(pg_data_t *pgdat, struct page *page) { - int page_lru; + int page_lru, nr = compound_nr(page), order = compound_order(page); - VM_BUG_ON_PAGE(compound_order(page) && !PageTransHuge(page), page); + VM_BUG_ON_PAGE(order && !PageTransHuge(page), page); /* Avoid migrating to a node that is nearly full */ - if (!migrate_balanced_pgdat(pgdat, compound_nr(page))) + if (!migrate_balanced_pgdat(pgdat, nr)) { + int migration_node, z; + pg_data_t *migration_pgdat; + + if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING) || + !(node_reclaim_mode & RECLAIM_MIGRATE)) + return 0; + /* + * The slow memory node need to have enough + * free pages to demote the cold pages in the + * fast memory node to it. + */ + migration_node = next_demotion_node(pgdat->node_id); + if (migration_node == NUMA_NO_NODE) + return 0; + migration_pgdat = NODE_DATA(migration_node); + if (!migrate_balanced_pgdat(migration_pgdat, nr)) + return 0; + for (z = pgdat->nr_zones - 1; z >= 0; z--) { + if (populated_zone(pgdat->node_zones + z)) + break; + } + wakeup_kswapd(pgdat->node_zones + z, 0, order, ZONE_MOVABLE); return 0; + } if (isolate_lru_page(page)) return 0; diff --git a/mm/vmscan.c b/mm/vmscan.c index da80b98d6b57..c3544030764d 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -58,6 +58,7 @@ #include #include +#include #include "internal.h" @@ -3544,6 +3545,12 @@ static bool pgdat_watermark_boosted(pg_data_t *pgdat, int highest_zoneidx) return false; } +/* + * Keep the free pages on fast memory node a little more than the high + * watermark to accommodate the promoted pages. + */ +#define NUMA_BALANCING_ADDON_WATERMARK (10UL * 1024 * 1024 >> PAGE_SHIFT) + /* * Returns true if there is an eligible zone balanced for the request order * and highest_zoneidx @@ -3565,6 +3572,14 @@ static bool pgdat_balanced(pg_data_t *pgdat, int order, int highest_zoneidx) continue; mark = high_wmark_pages(zone); + if (sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING && + next_demotion_node(pgdat->node_id) != NUMA_NO_NODE) { + unsigned long addon_mark; + + addon_mark = min(NUMA_BALANCING_ADDON_WATERMARK, + pgdat->node_present_pages >> 6); + mark += addon_mark; + } if (zone_watermark_ok_safe(zone, order, mark, highest_zoneidx)) return true; }