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=-20.7 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,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 67FC4C2B9F4 for ; Mon, 14 Jun 2021 14:57:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4DB8861019 for ; Mon, 14 Jun 2021 14:57:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233257AbhFNO7y (ORCPT ); Mon, 14 Jun 2021 10:59:54 -0400 Received: from so254-9.mailgun.net ([198.61.254.9]:46955 "EHLO so254-9.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233178AbhFNO7v (ORCPT ); Mon, 14 Jun 2021 10:59:51 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1623682668; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: References: Cc: To: From: Subject: Sender; bh=IDDJbdI+ADpNk8hfKYMwtRef1AumMkvGJe0gpE+1oTI=; b=AeOAYdfiXmKgzu+bOYBoLulr0UfTj2viUro+7oC82wU99xDzYoTcqluia3vP5z1t+90Dghkd gtDD/Gg8UdAc8wwOx9Qs2LiatYveyXBwUvYYyYUWYUw3Bqu+iTOAO/gz7ZGupPv8JZML6WWj vw8R9Y6vL5CgigkwSahUWdMYiB8= 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-n02.prod.us-west-2.postgun.com with SMTP id 60c76e5e2eaeb98b5e85c2ca (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Mon, 14 Jun 2021 14:57:34 GMT Sender: charante=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id EC146C43149; Mon, 14 Jun 2021 14:57:33 +0000 (UTC) Received: from [192.168.29.110] (unknown [49.37.158.62]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: charante) by smtp.codeaurora.org (Postfix) with ESMTPSA id 7F3FBC433D3; Mon, 14 Jun 2021 14:57:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 7F3FBC433D3 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 Subject: Re: [PATCH v3 1/2] mm: compaction: support triggering of proactive compaction by user From: Charan Teja Kalla 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 References: <7db6a29a64b29d56cde46c713204428a4b95f0ab.1622454385.git.charante@codeaurora.org> Message-ID: <95e6a3dd-51c5-3123-a03b-6aa783987a4b@codeaurora.org> Date: Mon, 14 Jun 2021 20:27:21 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Just another ping to have your comments. Thanks in advance!! On 6/7/2021 4:08 PM, Charan Teja Kalla wrote: > A gentle ping. > > --Charan > > On 5/31/2021 4:24 PM, Charan Teja Reddy wrote: >> 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; >> > -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project