Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754545AbZKMGaP (ORCPT ); Fri, 13 Nov 2009 01:30:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754193AbZKMGaL (ORCPT ); Fri, 13 Nov 2009 01:30:11 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:55997 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754191AbZKMGaK convert rfc822-to-8bit (ORCPT ); Fri, 13 Nov 2009 01:30:10 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: Hugh Dickins Subject: Re: [PATCH 2/6] mm: mlocking in try_to_unmap_one Cc: kosaki.motohiro@jp.fujitsu.com, Andrew Morton , Izik Eidus , Andrea Arcangeli , Nick Piggin , Rik van Riel , Lee Schermerhorn , linux-kernel@vger.kernel.org, linux-mm@kvack.org In-Reply-To: References: Message-Id: <20091113151554.33C2.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 8BIT X-Mailer: Becky! ver. 2.50.07 [ja] Date: Fri, 13 Nov 2009 15:30:10 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3017 Lines: 115 > @@ -787,6 +787,8 @@ static int try_to_unmap_one(struct page > ret = SWAP_MLOCK; > goto out_unmap; > } > + if (MLOCK_PAGES && TTU_ACTION(flags) == TTU_MUNLOCK) > + goto out_unmap; > } > if (!(flags & TTU_IGNORE_ACCESS)) { > if (ptep_clear_flush_young_notify(vma, address, pte)) { > @@ -852,12 +854,22 @@ static int try_to_unmap_one(struct page > } else > dec_mm_counter(mm, file_rss); > > - > page_remove_rmap(page); > page_cache_release(page); > > out_unmap: > pte_unmap_unlock(pte, ptl); > + > + if (MLOCK_PAGES && ret == SWAP_MLOCK) { > + ret = SWAP_AGAIN; > + if (down_read_trylock(&vma->vm_mm->mmap_sem)) { > + if (vma->vm_flags & VM_LOCKED) { > + mlock_vma_page(page); > + ret = SWAP_MLOCK; > + } > + up_read(&vma->vm_mm->mmap_sem); > + } > + } > out: Very small nit. How about this? ------------------------------------------------------------ >From 9d4b507572eccf88dcaa02e650df59874216528c Mon Sep 17 00:00:00 2001 From: KOSAKI Motohiro Date: Fri, 13 Nov 2009 15:00:04 +0900 Subject: [PATCH] Simplify try_to_unmap_one() SWAP_MLOCK mean "We marked the page as PG_MLOCK, please move it to unevictable-lru". So, following code is easy confusable. if (vma->vm_flags & VM_LOCKED) { ret = SWAP_MLOCK; goto out_unmap; } Plus, if the VMA doesn't have VM_LOCKED, We don't need to check the needed of calling mlock_vma_page(). Signed-off-by: KOSAKI Motohiro --- mm/rmap.c | 25 ++++++++++++------------- 1 files changed, 12 insertions(+), 13 deletions(-) diff --git a/mm/rmap.c b/mm/rmap.c index 4440a86..81a168c 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -784,10 +784,8 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, * skipped over this mm) then we should reactivate it. */ if (!(flags & TTU_IGNORE_MLOCK)) { - if (vma->vm_flags & VM_LOCKED) { - ret = SWAP_MLOCK; - goto out_unmap; - } + if (vma->vm_flags & VM_LOCKED) + goto out_unlock; if (MLOCK_PAGES && TTU_ACTION(flags) == TTU_MUNLOCK) goto out_unmap; } @@ -856,18 +854,19 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma, out_unmap: pte_unmap_unlock(pte, ptl); +out: + return ret; - if (MLOCK_PAGES && ret == SWAP_MLOCK) { - ret = SWAP_AGAIN; - if (down_read_trylock(&vma->vm_mm->mmap_sem)) { - if (vma->vm_flags & VM_LOCKED) { - mlock_vma_page(page); - ret = SWAP_MLOCK; - } - up_read(&vma->vm_mm->mmap_sem); +out_unlock: + pte_unmap_unlock(pte, ptl); + + if (down_read_trylock(&vma->vm_mm->mmap_sem)) { + if (vma->vm_flags & VM_LOCKED) { + mlock_vma_page(page); + ret = SWAP_MLOCK; } + up_read(&vma->vm_mm->mmap_sem); } -out: return ret; } -- 1.6.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/