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=-21.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 7E606C47082 for ; Mon, 31 May 2021 10:56:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5CE4C6124C for ; Mon, 31 May 2021 10:56:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231349AbhEaK55 (ORCPT ); Mon, 31 May 2021 06:57:57 -0400 Received: from so254-9.mailgun.net ([198.61.254.9]:34309 "EHLO so254-9.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231315AbhEaK5t (ORCPT ); Mon, 31 May 2021 06:57:49 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1622458570; h=References: In-Reply-To: References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=dD6c4S8BL7vEgkOGyQwHpR0yknaNB2G/opoaTalvr+8=; b=DYe/acqq3MEBPyhZ0zhSI8XTuyGVoSJGdf/pbfiqEQKusv89PwOzqxJa0ObeVOSk1Swj9d5g 9yszmeOqs0PhnGi9wJBBxwrwz4YfdfzVuOT0ZFAQq7Q57PYH8eI3WLIyDPhgfstg/JUJDLV5 8yqiueqkrN5wbhtVROkavNrokzo= X-Mailgun-Sending-Ip: 198.61.254.9 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n07.prod.us-west-2.postgun.com with SMTP id 60b4c0c981efe91cda944be4 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Mon, 31 May 2021 10:56:09 GMT Sender: charante=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 114A0C433F1; Mon, 31 May 2021 10:56:08 +0000 (UTC) Received: from hu-charante-hyd.qualcomm.com (unknown [202.46.22.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: charante) by smtp.codeaurora.org (Postfix) with ESMTPSA id 92B40C43460; Mon, 31 May 2021 10:56:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 92B40C43460 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=charante@codeaurora.org From: Charan Teja Reddy To: akpm@linux-foundation.org, vbabka@suse.cz, nigupta@nvidia.com, hannes@cmpxchg.org, corbet@lwn.net, mcgrof@kernel.org, keescook@chromium.org, yzaikin@google.com, aarcange@redhat.com, cl@linux.com, xi.fengfei@h3c.com, mchehab+huawei@kernel.org, andrew.a.klychkov@gmail.com, dave.hansen@linux.intel.com, bhe@redhat.com, iamjoonsoo.kim@lge.com, mateusznosek0@gmail.com, sh_def@163.com, vinmenon@codeaurora.org Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Charan Teja Reddy Subject: [PATCH v3 1/2] mm: compaction: support triggering of proactive compaction by user Date: Mon, 31 May 2021 16:24:51 +0530 Message-Id: <7db6a29a64b29d56cde46c713204428a4b95f0ab.1622454385.git.charante@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: References: In-Reply-To: References: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The proactive compaction[1] gets triggered for every 500msec and run compaction on the node for COMPACTION_HPAGE_ORDER (usually order-9) pages based on the value set to sysctl.compaction_proactiveness. Triggering the compaction for every 500msec in search of COMPACTION_HPAGE_ORDER pages is not needed for all applications, especially on the embedded system usecases which may have few MB's of RAM. Enabling the proactive compaction in its state will endup in running almost always on such systems. Other side, proactive compaction can still be very much useful for getting a set of higher order pages in some controllable manner(controlled by using the sysctl.compaction_proactiveness). Thus on systems where enabling the proactive compaction always may proove not required, can trigger the same from user space on write to its sysctl interface. As an example, say app launcher decide to launch the memory heavy application which can be launched fast if it gets more higher order pages thus launcher can prepare the system in advance by triggering the proactive compaction from userspace. This triggering of proactive compaction is done on a write to sysctl.compaction_proactiveness by user. [1]https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=facdaa917c4d5a376d09d25865f5a863f906234a Signed-off-by: Charan Teja Reddy --- changes in V2: - https://lore.kernel.org/patchwork/patch/1431283/ changes in V1: - https://lore.kernel.org/lkml/1619098678-8501-1-git-send-email-charante@codeaurora.org/ Documentation/admin-guide/sysctl/vm.rst | 3 ++- include/linux/compaction.h | 2 ++ include/linux/mmzone.h | 1 + kernel/sysctl.c | 2 +- mm/compaction.c | 44 ++++++++++++++++++++++++++++++--- 5 files changed, 47 insertions(+), 5 deletions(-) diff --git a/Documentation/admin-guide/sysctl/vm.rst b/Documentation/admin-guide/sysctl/vm.rst index 586cd4b..5e8097d 100644 --- a/Documentation/admin-guide/sysctl/vm.rst +++ b/Documentation/admin-guide/sysctl/vm.rst @@ -126,7 +126,8 @@ compaction_proactiveness This tunable takes a value in the range [0, 100] with a default value of 20. This tunable determines how aggressively compaction is done in the -background. Setting it to 0 disables proactive compaction. +background. On write of non zero value to this tunable will immediately +trigger the proactive compaction. Setting it to 0 disables proactive compaction. Note that compaction has a non-trivial system-wide impact as pages belonging to different processes are moved around, which could also lead diff --git a/include/linux/compaction.h b/include/linux/compaction.h index 4221888..04d5d9f 100644 --- a/include/linux/compaction.h +++ b/include/linux/compaction.h @@ -84,6 +84,8 @@ static inline unsigned long compact_gap(unsigned int order) extern unsigned int sysctl_compaction_proactiveness; extern int sysctl_compaction_handler(struct ctl_table *table, int write, void *buffer, size_t *length, loff_t *ppos); +extern int compaction_proactiveness_sysctl_handler(struct ctl_table *table, + int write, void *buffer, size_t *length, loff_t *ppos); extern int sysctl_extfrag_threshold; extern int sysctl_compact_unevictable_allowed; diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 0d53eba..9455809 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -815,6 +815,7 @@ typedef struct pglist_data { enum zone_type kcompactd_highest_zoneidx; wait_queue_head_t kcompactd_wait; struct task_struct *kcompactd; + bool proactive_compact_trigger; #endif /* * This is a per-node reserve of pages that are not available diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 14edf84..bed2fad 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -2840,7 +2840,7 @@ static struct ctl_table vm_table[] = { .data = &sysctl_compaction_proactiveness, .maxlen = sizeof(sysctl_compaction_proactiveness), .mode = 0644, - .proc_handler = proc_dointvec_minmax, + .proc_handler = compaction_proactiveness_sysctl_handler, .extra1 = SYSCTL_ZERO, .extra2 = &one_hundred, }, diff --git a/mm/compaction.c b/mm/compaction.c index 84fde27..197e203 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -2708,6 +2708,30 @@ static void compact_nodes(void) */ unsigned int __read_mostly sysctl_compaction_proactiveness = 20; +int compaction_proactiveness_sysctl_handler(struct ctl_table *table, int write, + void *buffer, size_t *length, loff_t *ppos) +{ + int rc, nid; + + rc = proc_dointvec_minmax(table, write, buffer, length, ppos); + if (rc) + return rc; + + if (write && sysctl_compaction_proactiveness) { + for_each_online_node(nid) { + pg_data_t *pgdat = NODE_DATA(nid); + + if (pgdat->proactive_compact_trigger) + continue; + + pgdat->proactive_compact_trigger = true; + wake_up_interruptible(&pgdat->kcompactd_wait); + } + } + + return 0; +} + /* * This is the entry point for compacting all nodes via * /proc/sys/vm/compact_memory @@ -2752,7 +2776,8 @@ void compaction_unregister_node(struct node *node) static inline bool kcompactd_work_requested(pg_data_t *pgdat) { - return pgdat->kcompactd_max_order > 0 || kthread_should_stop(); + return pgdat->kcompactd_max_order > 0 || kthread_should_stop() || + pgdat->proactive_compact_trigger; } static bool kcompactd_node_suitable(pg_data_t *pgdat) @@ -2905,7 +2930,8 @@ static int kcompactd(void *p) trace_mm_compaction_kcompactd_sleep(pgdat->node_id); if (wait_event_freezable_timeout(pgdat->kcompactd_wait, kcompactd_work_requested(pgdat), - msecs_to_jiffies(HPAGE_FRAG_CHECK_INTERVAL_MSEC))) { + msecs_to_jiffies(HPAGE_FRAG_CHECK_INTERVAL_MSEC)) && + !pgdat->proactive_compact_trigger) { psi_memstall_enter(&pflags); kcompactd_do_work(pgdat); @@ -2917,10 +2943,20 @@ static int kcompactd(void *p) if (should_proactive_compact_node(pgdat)) { unsigned int prev_score, score; - if (proactive_defer) { + /* + * On wakeup of proactive compaction by sysctl + * write, ignore the accumulated defer score. + * Anyway, if the proactive compaction didn't + * make any progress for the new value, it will + * be further deferred by 2^COMPACT_MAX_DEFER_SHIFT + * times. + */ + if (proactive_defer && + !pgdat->proactive_compact_trigger) { proactive_defer--; continue; } + prev_score = fragmentation_score_node(pgdat); proactive_compact_node(pgdat); score = fragmentation_score_node(pgdat); @@ -2931,6 +2967,8 @@ static int kcompactd(void *p) proactive_defer = score < prev_score ? 0 : 1 << COMPACT_MAX_DEFER_SHIFT; } + if (pgdat->proactive_compact_trigger) + pgdat->proactive_compact_trigger = false; } return 0; -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation