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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_GIT 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 1F6ADC3F2D2 for ; Mon, 2 Mar 2020 11:03:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E79ED2166E for ; Mon, 2 Mar 2020 11:03:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727634AbgCBLD5 (ORCPT ); Mon, 2 Mar 2020 06:03:57 -0500 Received: from out30-54.freemail.mail.aliyun.com ([115.124.30.54]:48618 "EHLO out30-54.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727901AbgCBLD5 (ORCPT ); Mon, 2 Mar 2020 06:03:57 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R161e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04407;MF=alex.shi@linux.alibaba.com;NM=1;PH=DS;RN=14;SR=0;TI=SMTPD_---0TrQzvOW_1583146854; Received: from localhost(mailfrom:alex.shi@linux.alibaba.com fp:SMTPD_---0TrQzvOW_1583146854) by smtp.aliyun-inc.com(127.0.0.1); Mon, 02 Mar 2020 19:00:54 +0800 From: Alex Shi To: cgroups@vger.kernel.org, akpm@linux-foundation.org, mgorman@techsingularity.net, tj@kernel.org, hughd@google.com, khlebnikov@yandex-team.ru, daniel.m.jordan@oracle.com, yang.shi@linux.alibaba.com, willy@infradead.org, hannes@cmpxchg.org, lkp@intel.com Cc: Alex Shi , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v9 03/20] mm/page_idle: no unlikely double check for idle page counting Date: Mon, 2 Mar 2020 19:00:13 +0800 Message-Id: <1583146830-169516-4-git-send-email-alex.shi@linux.alibaba.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1583146830-169516-1-git-send-email-alex.shi@linux.alibaba.com> References: <1583146830-169516-1-git-send-email-alex.shi@linux.alibaba.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As func comments mentioned, few isolated page missing be tolerated. So why not do further to drop the unlikely double check. That won't cause more idle pages, but reduce a lock contention. This is also a preparation for later new page isolation feature. Signed-off-by: Alex Shi Cc: Andrew Morton Cc: Johannes Weiner Cc: Matthew Wilcox Cc: Hugh Dickins Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org --- mm/page_idle.c | 8 -------- 1 file changed, 8 deletions(-) diff --git a/mm/page_idle.c b/mm/page_idle.c index 295512465065..914df63948b1 100644 --- a/mm/page_idle.c +++ b/mm/page_idle.c @@ -31,7 +31,6 @@ static struct page *page_idle_get_page(unsigned long pfn) { struct page *page; - pg_data_t *pgdat; if (!pfn_valid(pfn)) return NULL; @@ -41,13 +40,6 @@ static struct page *page_idle_get_page(unsigned long pfn) !get_page_unless_zero(page)) return NULL; - pgdat = page_pgdat(page); - spin_lock_irq(&pgdat->lru_lock); - if (unlikely(!PageLRU(page))) { - put_page(page); - page = NULL; - } - spin_unlock_irq(&pgdat->lru_lock); return page; } -- 1.8.3.1 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Shi Subject: [PATCH v9 03/20] mm/page_idle: no unlikely double check for idle page counting Date: Mon, 2 Mar 2020 19:00:13 +0800 Message-ID: <1583146830-169516-4-git-send-email-alex.shi@linux.alibaba.com> References: <1583146830-169516-1-git-send-email-alex.shi@linux.alibaba.com> Return-path: In-Reply-To: <1583146830-169516-1-git-send-email-alex.shi-KPsoFbNs7GizrGE5bRqYAgC/G2K4zDHf@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, mgorman-3eNAlZScCAx27rWaFMvyedHuzzzSOjJt@public.gmane.org, tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, hughd-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, khlebnikov-XoJtRXgx1JseBXzfvpsJ4g@public.gmane.org, daniel.m.jordan-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, yang.shi-KPsoFbNs7GizrGE5bRqYAgC/G2K4zDHf@public.gmane.org, willy-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org, lkp-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org Cc: Alex Shi , linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org As func comments mentioned, few isolated page missing be tolerated. So why not do further to drop the unlikely double check. That won't cause more idle pages, but reduce a lock contention. This is also a preparation for later new page isolation feature. Signed-off-by: Alex Shi Cc: Andrew Morton Cc: Johannes Weiner Cc: Matthew Wilcox Cc: Hugh Dickins Cc: linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org --- mm/page_idle.c | 8 -------- 1 file changed, 8 deletions(-) diff --git a/mm/page_idle.c b/mm/page_idle.c index 295512465065..914df63948b1 100644 --- a/mm/page_idle.c +++ b/mm/page_idle.c @@ -31,7 +31,6 @@ static struct page *page_idle_get_page(unsigned long pfn) { struct page *page; - pg_data_t *pgdat; if (!pfn_valid(pfn)) return NULL; @@ -41,13 +40,6 @@ static struct page *page_idle_get_page(unsigned long pfn) !get_page_unless_zero(page)) return NULL; - pgdat = page_pgdat(page); - spin_lock_irq(&pgdat->lru_lock); - if (unlikely(!PageLRU(page))) { - put_page(page); - page = NULL; - } - spin_unlock_irq(&pgdat->lru_lock); return page; } -- 1.8.3.1