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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 C24CFECDE4B for ; Thu, 8 Nov 2018 08:23:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D1D920827 for ; Thu, 8 Nov 2018 08:23:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8D1D920827 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726892AbeKHR6D (ORCPT ); Thu, 8 Nov 2018 12:58:03 -0500 Received: from alexa-out-blr-02.qualcomm.com ([103.229.18.198]:32583 "EHLO alexa-out-blr.qualcomm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726162AbeKHR6D (ORCPT ); Thu, 8 Nov 2018 12:58:03 -0500 X-IronPort-AV: E=Sophos;i="5.54,478,1534789800"; d="scan'208";a="233248" Received: from ironmsg01-blr.qualcomm.com ([10.86.208.130]) by alexa-out-blr.qualcomm.com with ESMTP/TLS/AES256-SHA; 08 Nov 2018 13:53:26 +0530 X-IronPort-AV: E=McAfee;i="5900,7806,9070"; a="5699124" Received: from blr-ubuntu-104.ap.qualcomm.com (HELO blr-ubuntu-104.qualcomm.com) ([10.79.40.64]) by ironmsg01-blr.qualcomm.com with ESMTP; 08 Nov 2018 13:53:25 +0530 Received: by blr-ubuntu-104.qualcomm.com (Postfix, from userid 346745) id 6FA5923A8; Thu, 8 Nov 2018 13:53:25 +0530 (IST) From: Arun KS To: akpm@linux-foundation.org, keescook@chromium.org, khlebnikov@yandex-team.ru, minchan@kernel.org, mhocko@kernel.org, vbabka@suse.cz, osalvador@suse.de, linux-kernel@vger.kernel.org, linux-mm@kvack.org Cc: getarunks@gmail.com, Arun KS Subject: [PATCH v3 4/4] mm: Remove managed_page_count spinlock Date: Thu, 8 Nov 2018 13:53:18 +0530 Message-Id: <1541665398-29925-5-git-send-email-arunks@codeaurora.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1541665398-29925-1-git-send-email-arunks@codeaurora.org> References: <1541665398-29925-1-git-send-email-arunks@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now totalram_pages and managed_pages are atomic varibles. No need of managed_page_count spinlock. Signed-off-by: Arun KS Reviewed-by: Konstantin Khlebnikov Acked-by: Michal Hocko Acked-by: Vlastimil Babka --- include/linux/mmzone.h | 6 ------ mm/page_alloc.c | 5 ----- 2 files changed, 11 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index e73dc31..c71b4d9 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -428,12 +428,6 @@ struct zone { * Write access to present_pages at runtime should be protected by * mem_hotplug_begin/end(). Any reader who can't tolerant drift of * present_pages should get_online_mems() to get a stable value. - * - * Read access to managed_pages should be safe because it's unsigned - * long. Write access to zone->managed_pages and totalram_pages are - * protected by managed_page_count_lock at runtime. Idealy only - * adjust_managed_page_count() should be used instead of directly - * touching zone->managed_pages and totalram_pages. */ atomic_long_t managed_pages; unsigned long spanned_pages; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index f8b64cc..26c5e14 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -122,9 +122,6 @@ }; EXPORT_SYMBOL(node_states); -/* Protect totalram_pages and zone->managed_pages */ -static DEFINE_SPINLOCK(managed_page_count_lock); - atomic_long_t _totalram_pages __read_mostly; EXPORT_SYMBOL(_totalram_pages); unsigned long totalreserve_pages __read_mostly; @@ -7065,14 +7062,12 @@ static int __init cmdline_parse_movablecore(char *p) void adjust_managed_page_count(struct page *page, long count) { - spin_lock(&managed_page_count_lock); atomic_long_add(count, &page_zone(page)->managed_pages); totalram_pages_add(count); #ifdef CONFIG_HIGHMEM if (PageHighMem(page)) totalhigh_pages_add(count); #endif - spin_unlock(&managed_page_count_lock); } EXPORT_SYMBOL(adjust_managed_page_count); -- 1.9.1