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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 66234C433EF for ; Fri, 4 Feb 2022 17:37:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376967AbiBDRhd (ORCPT ); Fri, 4 Feb 2022 12:37:33 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:43247 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1376939AbiBDRhQ (ORCPT ); Fri, 4 Feb 2022 12:37:16 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643996236; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=EBwE2vdT3R+yn90gfFOhWS3yL67SYk8R43YGuWDZepg=; b=EHiNyDmOXcpKqPjxF4iLYgbR+tdJs9rR6qkLfKesDccg8JWM7FlHg2BiKpSdJsJKPw2yXS Kf2maHL3NvTbSF42p7nzoqZno1HhwtIVOaDXCcVeQE1qMuqkY1K00woW5jh9G6AzV3VpTr ifK5J0mWoV0MK0/6H9ieqwPDUU/5DqA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-526-jAvjFZXpMDKfK6UsdsQxgA-1; Fri, 04 Feb 2022 12:37:13 -0500 X-MC-Unique: jAvjFZXpMDKfK6UsdsQxgA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B88518710FB; Fri, 4 Feb 2022 17:37:11 +0000 (UTC) Received: from fuller.cnet (ovpn-112-3.gru2.redhat.com [10.97.112.3]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 79D2882764; Fri, 4 Feb 2022 17:37:11 +0000 (UTC) Received: by fuller.cnet (Postfix, from userid 1000) id 8F96E416EEF4; Fri, 4 Feb 2022 14:36:46 -0300 (-03) Message-ID: <20220204173554.763888172@fedora.localdomain> User-Agent: quilt/0.66 Date: Fri, 04 Feb 2022 14:35:44 -0300 From: Marcelo Tosatti To: linux-kernel@vger.kernel.org Cc: Nitesh Lal , Nicolas Saenz Julienne , Frederic Weisbecker , Christoph Lameter , Juri Lelli , Peter Zijlstra , Alex Belits , Peter Xu , Thomas Gleixner , Daniel Bristot de Oliveira , Oscar Shiang , Marcelo Tosatti Subject: [patch v11 07/13] task isolation: sync vmstats conditional on changes References: <20220204173537.429902988@fedora.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Rather than syncing VM-stats on every return to userspace (or VM-entry), keep track of changes through a per-CPU bool. This improves performance when enabling task isolated for vcpu VMs. Signed-off-by: Marcelo Tosatti --- v11: - Add TIF_TASK_ISOL bit to thread info flags and use it to decide whether to perform task isolation work on return to userspace include/linux/vmstat.h | 13 ++++++++++++- mm/vmstat.c | 29 ++++++++++++++++++++++++++++- 2 files changed, 40 insertions(+), 2 deletions(-) Index: linux-2.6/include/linux/vmstat.h =================================================================== --- linux-2.6.orig/include/linux/vmstat.h +++ linux-2.6/include/linux/vmstat.h @@ -22,7 +22,18 @@ int sysctl_vm_numa_stat_handler(struct c #endif #if defined(CONFIG_SMP) && defined(CONFIG_TASK_ISOLATION) -void sync_vmstat(void); +DECLARE_PER_CPU_ALIGNED(bool, vmstat_dirty); + +extern struct static_key vmstat_sync_enabled; + +void __sync_vmstat(void); +static inline void sync_vmstat(void) +{ + if (static_key_false(&vmstat_sync_enabled)) + __sync_vmstat(); +} + +void init_sync_vmstat(void); #else static inline void sync_vmstat(void) { Index: linux-2.6/mm/vmstat.c =================================================================== --- linux-2.6.orig/mm/vmstat.c +++ linux-2.6/mm/vmstat.c @@ -334,6 +334,31 @@ void set_pgdat_percpu_threshold(pg_data_ } } +#ifdef CONFIG_TASK_ISOLATION +struct static_key vmstat_sync_enabled; +DEFINE_PER_CPU_ALIGNED(bool, vmstat_dirty); + +static inline void mark_vmstat_dirty(void) +{ + if (!static_key_false(&vmstat_sync_enabled)) + return; + + raw_cpu_write(vmstat_dirty, true); + set_thread_flag(TIF_TASK_ISOL); +} + +void init_sync_vmstat(void) +{ + raw_cpu_write(vmstat_dirty, true); + set_thread_flag(TIF_TASK_ISOL); +} +EXPORT_SYMBOL_GPL(vmstat_dirty); +#else +static inline void mark_vmstat_dirty(void) +{ +} +#endif + /* * For use when we know that interrupts are disabled, * or when we know that preemption is disabled and that @@ -366,6 +391,7 @@ void __mod_zone_page_state(struct zone * x = 0; } __this_cpu_write(*p, x); + mark_vmstat_dirty(); if (IS_ENABLED(CONFIG_PREEMPT_RT)) preempt_enable(); @@ -404,6 +430,7 @@ void __mod_node_page_state(struct pglist x = 0; } __this_cpu_write(*p, x); + mark_vmstat_dirty(); if (IS_ENABLED(CONFIG_PREEMPT_RT)) preempt_enable(); @@ -602,6 +629,7 @@ static inline void mod_zone_state(struct if (z) zone_page_state_add(z, zone, item); + mark_vmstat_dirty(); } void mod_zone_page_state(struct zone *zone, enum zone_stat_item item, @@ -670,6 +698,7 @@ static inline void mod_node_state(struct if (z) node_page_state_add(z, pgdat, item); + mark_vmstat_dirty(); } void mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item, @@ -1087,6 +1116,7 @@ static void fill_contig_page_info(struct info->free_blocks_suitable += blocks << (order - suitable_order); } + mark_vmstat_dirty(); } /* @@ -1443,6 +1473,7 @@ static void walk_zones_in_node(struct se if (!nolock) spin_unlock_irqrestore(&zone->lock, flags); } + mark_vmstat_dirty(); } #endif @@ -1512,6 +1543,7 @@ static void pagetypeinfo_showfree_print( } seq_putc(m, '\n'); } + mark_vmstat_dirty(); } /* Print out the free pages at each order for each migatetype */ @@ -1932,6 +1964,7 @@ static void vmstat_update(struct work_st this_cpu_ptr(&vmstat_work), round_jiffies_relative(sysctl_stat_interval)); } + mark_vmstat_dirty(); } /* @@ -2019,13 +2052,14 @@ static void vmstat_shepherd(struct work_ } #ifdef CONFIG_TASK_ISOLATION -void sync_vmstat(void) +void __sync_vmstat(void) { int cpu; cpu = get_cpu(); refresh_cpu_vm_stats(false); + raw_cpu_write(vmstat_dirty, false); put_cpu(); /*