From patchwork Mon Apr 19 14:13:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mel Gorman X-Patchwork-Id: 12211931 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 B90B9C433ED for ; Mon, 19 Apr 2021 14:14:56 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 48CE461157 for ; Mon, 19 Apr 2021 14:14:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 48CE461157 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=techsingularity.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id CD5D26B0075; Mon, 19 Apr 2021 10:14:55 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C849E6B0078; Mon, 19 Apr 2021 10:14:55 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B26986B0080; Mon, 19 Apr 2021 10:14:55 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0230.hostedemail.com [216.40.44.230]) by kanga.kvack.org (Postfix) with ESMTP id 9155C6B0075 for ; Mon, 19 Apr 2021 10:14:55 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 4F81C3641 for ; Mon, 19 Apr 2021 14:14:55 +0000 (UTC) X-FDA: 78049312950.02.D29677A Received: from outbound-smtp26.blacknight.com (outbound-smtp26.blacknight.com [81.17.249.194]) by imf20.hostedemail.com (Postfix) with ESMTP id 3CC50FC for ; Mon, 19 Apr 2021 14:14:48 +0000 (UTC) Received: from mail.blacknight.com (pemlinmail03.blacknight.ie [81.17.254.16]) by outbound-smtp26.blacknight.com (Postfix) with ESMTPS id 9B97ECAD96 for ; Mon, 19 Apr 2021 15:14:53 +0100 (IST) Received: (qmail 13413 invoked from network); 19 Apr 2021 14:14:53 -0000 Received: from unknown (HELO stampy.112glenside.lan) (mgorman@techsingularity.net@[84.203.22.4]) by 81.17.254.9 with ESMTPA; 19 Apr 2021 14:14:53 -0000 From: Mel Gorman To: Linux-MM , Linux-RT-Users Cc: LKML , Chuck Lever , Jesper Dangaard Brouer , Thomas Gleixner , Peter Zijlstra , Ingo Molnar , Michal Hocko , Vlastimil Babka , Mel Gorman Subject: [PATCH 06/10] mm/page_alloc: Reduce duration that IRQs are disabled for VM counters Date: Mon, 19 Apr 2021 15:13:37 +0100 Message-Id: <20210419141341.26047-7-mgorman@techsingularity.net> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210419141341.26047-1-mgorman@techsingularity.net> References: <20210419141341.26047-1-mgorman@techsingularity.net> MIME-Version: 1.0 X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 3CC50FC X-Stat-Signature: 3r4k1w41y4gymzuxgcars1mrtrgwoh3j Received-SPF: none (techsingularity.net>: No applicable sender policy available) receiver=imf20; identity=mailfrom; envelope-from=""; helo=outbound-smtp26.blacknight.com; client-ip=81.17.249.194 X-HE-DKIM-Result: none/none X-HE-Tag: 1618841688-63015 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: IRQs are left disabled for the zone and node VM event counters. This is unnecessary as the affected counters are allowed to race for preemmption and IRQs. This patch reduces the scope of IRQs being disabled via local_[lock|unlock]_irq on !PREEMPT_RT kernels. One __mod_zone_freepage_state is still called with IRQs disabled. While this could be moved out, it's not free on all architectures as some require IRQs to be disabled for mod_zone_page_state on !PREEMPT_RT kernels. Signed-off-by: Mel Gorman Acked-by: Vlastimil Babka --- mm/page_alloc.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index cff0f1c98b28..295624fe293b 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -3474,11 +3474,11 @@ static struct page *rmqueue_pcplist(struct zone *preferred_zone, pcp = this_cpu_ptr(zone->per_cpu_pageset); list = &pcp->lists[migratetype]; page = __rmqueue_pcplist(zone, migratetype, alloc_flags, pcp, list); + local_unlock_irqrestore(&pagesets.lock, flags); if (page) { __count_zid_vm_events(PGALLOC, page_zonenum(page), 1); zone_statistics(preferred_zone, zone, 1); } - local_unlock_irqrestore(&pagesets.lock, flags); return page; } @@ -3530,15 +3530,15 @@ struct page *rmqueue(struct zone *preferred_zone, if (!page) page = __rmqueue(zone, order, migratetype, alloc_flags); } while (page && check_new_pages(page, order)); - spin_unlock(&zone->lock); if (!page) goto failed; + __mod_zone_freepage_state(zone, -(1 << order), get_pcppage_migratetype(page)); + spin_unlock_irqrestore(&zone->lock, flags); __count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order); zone_statistics(preferred_zone, zone, 1); - local_irq_restore(flags); out: /* Separate test+clear to avoid unnecessary atomics */ @@ -3551,7 +3551,7 @@ struct page *rmqueue(struct zone *preferred_zone, return page; failed: - local_irq_restore(flags); + spin_unlock_irqrestore(&zone->lock, flags); return NULL; } @@ -5103,11 +5103,11 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid, nr_populated++; } + local_unlock_irqrestore(&pagesets.lock, flags); + __count_zid_vm_events(PGALLOC, zone_idx(zone), nr_account); zone_statistics(ac.preferred_zoneref->zone, zone, nr_account); - local_unlock_irqrestore(&pagesets.lock, flags); - return nr_populated; failed_irq: