From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id 9C2746B0062 for ; Thu, 10 Dec 2009 02:31:25 -0500 (EST) Received: from m2.gw.fujitsu.co.jp ([10.0.50.72]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id nBA7VNQm023066 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Thu, 10 Dec 2009 16:31:23 +0900 Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 2BAC945DE62 for ; Thu, 10 Dec 2009 16:31:23 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (s2.gw.fujitsu.co.jp [10.0.50.92]) by m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 0D88745DE5D for ; Thu, 10 Dec 2009 16:31:23 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id EA6821DB8038 for ; Thu, 10 Dec 2009 16:31:22 +0900 (JST) Received: from m105.s.css.fujitsu.com (m105.s.css.fujitsu.com [10.249.87.105]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id 9FC4D1DB803F for ; Thu, 10 Dec 2009 16:31:22 +0900 (JST) From: KOSAKI Motohiro Subject: [RFC][PATCH v2 3/8] VM_LOCKED check don't need pte lock In-Reply-To: <20091210154822.2550.A69D9226@jp.fujitsu.com> References: <20091210154822.2550.A69D9226@jp.fujitsu.com> Message-Id: <20091210163033.2559.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Thu, 10 Dec 2009 16:31:21 +0900 (JST) Sender: owner-linux-mm@kvack.org To: LKML Cc: kosaki.motohiro@jp.fujitsu.com, linux-mm , Rik van Riel , Andrea Arcangeli , Larry Woodman List-ID: Currently, page_referenced_one() check VM_LOCKED after taking ptelock. But it's unnecessary. We can check VM_LOCKED before to take lock. This patch does it. Signed-off-by: KOSAKI Motohiro Reviewed-by: Rik van Riel --- mm/rmap.c | 13 ++++++------- 1 files changed, 6 insertions(+), 7 deletions(-) diff --git a/mm/rmap.c b/mm/rmap.c index 1b50425..fb0983a 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -383,21 +383,21 @@ int page_referenced_one(struct page *page, struct vm_area_struct *vma, spinlock_t *ptl; int referenced = 0; - pte = page_check_address(page, mm, address, &ptl, 0); - if (!pte) - goto out; - /* * Don't want to elevate referenced for mlocked page that gets this far, * in order that it progresses to try_to_unmap and is moved to the * unevictable list. */ if (vma->vm_flags & VM_LOCKED) { - *mapcount = 1; /* break early from loop */ + *mapcount = 0; /* break early from loop */ *vm_flags |= VM_LOCKED; - goto out_unmap; + goto out; } + pte = page_check_address(page, mm, address, &ptl, 0); + if (!pte) + goto out; + if (ptep_clear_flush_young_notify(vma, address, pte)) { /* * Don't treat a reference through a sequentially read @@ -416,7 +416,6 @@ int page_referenced_one(struct page *page, struct vm_area_struct *vma, rwsem_is_locked(&mm->mmap_sem)) referenced++; -out_unmap: (*mapcount)--; pte_unmap_unlock(pte, ptl); -- 1.6.5.2 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org