From patchwork Thu Nov 8 08:23:18 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arun KS X-Patchwork-Id: 10673687 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 50F5F15E9 for ; Thu, 8 Nov 2018 08:23:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 43C0028774 for ; Thu, 8 Nov 2018 08:23:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3805F287E0; Thu, 8 Nov 2018 08:23:38 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C2A0F28774 for ; Thu, 8 Nov 2018 08:23:37 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 477B66B05A3; Thu, 8 Nov 2018 03:23:30 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 3FE706B05A5; Thu, 8 Nov 2018 03:23:30 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2065F6B05A6; Thu, 8 Nov 2018 03:23:30 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from mail-pf1-f198.google.com (mail-pf1-f198.google.com [209.85.210.198]) by kanga.kvack.org (Postfix) with ESMTP id BD6966B05A3 for ; Thu, 8 Nov 2018 03:23:29 -0500 (EST) Received: by mail-pf1-f198.google.com with SMTP id f28-v6so5806942pfh.6 for ; Thu, 08 Nov 2018 00:23:29 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-original-authentication-results:x-gm-message-state:from:to:cc :subject:date:message-id:in-reply-to:references; bh=ButyDGhDCk2HuCgaJ33BiVu/ttZAdRpYbo3H/CAHuSI=; b=f3vNwVY/uDTi04JJn8psnLks5kQER+EwXhXkRtsfI7lUu/JIxGm3iWSFhG7P+w+pr4 5ytUBaAZ1Ysb0GZScR8sbaHIn+Rt81E1XAZL4dGH0A3hTvso/aCo0sK9fD8HNM51MRxz CJ6Yk94x+owUc6PfcU+zsPwIYJ4Zr3uEV2vu4olJnhllRmmIgs7736H5vnD2Vi3DnMZS IbC3nvLDv9/8T84EgdyfKPr6QMIrpqgJFbVvux18ghS/LRn9dsoprWaD0MDUI7EZGhok zlXQQEF8j0JREDXIF62O2K0Pn3Q6/i4vplsxkS0kbBrFhX5WxH0UQZZIiKKA0THRtFrf AGWA== X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of arunks@qualcomm.com designates 103.229.18.197 as permitted sender) smtp.mailfrom=arunks@qualcomm.com X-Gm-Message-State: AGRZ1gJ97eGTViKEq7iO8zPOdqBTUPzZqqPaBttzeO+0GdsaFFfoqU35 rmO1dJQR6wpI/BYUhMnKkVdqJAK6LGognpGU36QQEw0f6O15XjK2dfoCfsIb6xlYxtLGEd5m7Md RvfAQaNFIQo8D8aCbgwXdJtww8EJtWJm56s7qQPh1TnwWMMbwRujaXKMSmb+rf2g= X-Received: by 2002:a17:902:bd4a:: with SMTP id b10-v6mr3533193plx.171.1541665409465; Thu, 08 Nov 2018 00:23:29 -0800 (PST) X-Google-Smtp-Source: AJdET5dXuSxBUrCEjcsoZvy83DYwfGK3c6f+AUkIEP4gSx0L3wlhKmIfLq/GpOT+cvneT4DOhBLb X-Received: by 2002:a17:902:bd4a:: with SMTP id b10-v6mr3533145plx.171.1541665408183; Thu, 08 Nov 2018 00:23:28 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1541665408; cv=none; d=google.com; s=arc-20160816; b=NBWEZA1Attd+1ofXZdIZr0tUYEtX5aCfcIAfZJy6wrZnh+QwsAJLw2ZCAnrPZDPs6L NuXHXKDLstjAf6D0QDzuLgyuoFCodzd3S+yfBLLfiMPC4Cz4wZe8brpCZ0nW4hzZTvr9 tA8peupob4r8cngvZITNI3ExjSX/Y2bIq2yryNT4DXf0Lh1Pao3QjSZuVLie3eEevlEz 9R6aQeRariRrAMZsQbVmsNawTNWSsYEhdiB/9mj7Ni7aON5EesJvcql5g/W+ynaSwHUx LM5MRkRSfHrivXp9bZPE/B+4lQHyUMcSmbpYk+Mfys/2j4E1pkbS6tffBtAXrFV3iyFB zQCA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from; bh=ButyDGhDCk2HuCgaJ33BiVu/ttZAdRpYbo3H/CAHuSI=; b=ZcOivHB0aGJdPE8LCT9R8Y4Nl7GgoFldGLVPyWWyLt5YTV/RhjD5NIJzYR/91PLuCr nNKnoahCTcsPEAOJhKFb7HoSvdQKLVP+DyqBv/gNhsv+kV0If/gcpT9WGVZVhzck+Pu5 /Mn7Vv2V5D9aRg88ZpIt5F8L+RO0QHh1DiUmWk+Zh7hE0k7O6+/OD+rDuTDOrC6TsrfZ NTePQbuNcGlsFURFuK++oLOZZXErY+XBiMudMwHTMrBYt5EyKYu8oWCqqyTWvGeHLZ0Y 2jNe2Iy/qKq1PuErsugk9CXocc0e1iPA4y5gcRAJ0pnwb07UzulRh1TeXYNuaEVtAAqx ENBg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of arunks@qualcomm.com designates 103.229.18.197 as permitted sender) smtp.mailfrom=arunks@qualcomm.com Received: from alexa-out-blr-01.qualcomm.com (alexa-out-blr-01.qualcomm.com. [103.229.18.197]) by mx.google.com with ESMTPS id e129-v6si3825898pfg.205.2018.11.08.00.23.27 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 08 Nov 2018 00:23:28 -0800 (PST) Received-SPF: pass (google.com: domain of arunks@qualcomm.com designates 103.229.18.197 as permitted sender) client-ip=103.229.18.197; Authentication-Results: mx.google.com; spf=pass (google.com: domain of arunks@qualcomm.com designates 103.229.18.197 as permitted sender) smtp.mailfrom=arunks@qualcomm.com X-IronPort-AV: E=Sophos;i="5.54,478,1534789800"; d="scan'208";a="279037" Received: from ironmsg01-blr.qualcomm.com ([10.86.208.130]) by alexa-out-blr-01.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> 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: X-Virus-Scanned: ClamAV using ClamSMTP 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 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);