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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 6F58CC433ED for ; Wed, 5 May 2021 01:37:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 503BA61182 for ; Wed, 5 May 2021 01:37:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232071AbhEEBig (ORCPT ); Tue, 4 May 2021 21:38:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:41578 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231124AbhEEBig (ORCPT ); Tue, 4 May 2021 21:38:36 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 57B3061029; Wed, 5 May 2021 01:37:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1620178660; bh=ND4XtwAZnyCjDXycHQsnq9/CvM4Kiv7K7h0WltbKdo0=; h=Date:From:To:Subject:In-Reply-To:From; b=VpTtSjN21J18vRZ9nEozxtFgRfYjQW1dFNmqB7ocrDhTnD1jZzMfCh9rwh3zX1L/q IcO5aZ87g57ltv39nezWPQ+hv9vNzNe95qLlLljqgdNf+w1nRxhl6icBgb9aRWIWna Tsq25fAeiMVkP7UI2siYEOnWxssQsARRQ977qXyQ= Date: Tue, 04 May 2021 18:37:39 -0700 From: Andrew Morton To: akpm@linux-foundation.org, hughd@google.com, linmiaohe@huawei.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org Subject: [patch 092/143] ksm: use GET_KSM_PAGE_NOLOCK to get ksm page in remove_rmap_item_from_tree() Message-ID: <20210505013739.aebUkfVyn%akpm@linux-foundation.org> In-Reply-To: <20210504183219.a3cc46aee4013d77402276c5@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Miaohe Lin Subject: ksm: use GET_KSM_PAGE_NOLOCK to get ksm page in remove_rmap_item_from_tree() It's unnecessary to lock the page when get ksm page if we're going to remove the rmap item as page migration is irrelevant in this case. Use GET_KSM_PAGE_NOLOCK instead to save some page lock cycles. Link: https://lkml.kernel.org/r/20210330140228.45635-3-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Cc: Hugh Dickins Signed-off-by: Andrew Morton --- mm/ksm.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/mm/ksm.c~ksm-use-get_ksm_page_nolock-to-get-ksm-page-in-remove_rmap_item_from_tree +++ a/mm/ksm.c @@ -778,12 +778,11 @@ static void remove_rmap_item_from_tree(s struct page *page; stable_node = rmap_item->head; - page = get_ksm_page(stable_node, GET_KSM_PAGE_LOCK); + page = get_ksm_page(stable_node, GET_KSM_PAGE_NOLOCK); if (!page) goto out; hlist_del(&rmap_item->hlist); - unlock_page(page); put_page(page); if (!hlist_empty(&stable_node->hlist)) _