From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx175.postini.com [74.125.245.175]) by kanga.kvack.org (Postfix) with SMTP id CF74A6B0072 for ; Fri, 28 Sep 2012 09:30:19 -0400 (EDT) Date: Fri, 28 Sep 2012 15:30:06 +0200 From: Andrea Arcangeli Subject: Re: [patch for-3.6] mm, thp: fix mapped pages avoiding unevictable list on mlock Message-ID: <20120928133005.GA19474@redhat.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: David Rientjes Cc: Linus Torvalds , Andrew Morton , Naoya Horiguchi , KAMEZAWA Hiroyuki , Hugh Dickins , linux-kernel@vger.kernel.org, linux-mm@kvack.org, stable@vger.kernel.org Hi David, On Wed, Sep 19, 2012 at 06:19:27PM -0700, David Rientjes wrote: > + if ((flags & FOLL_MLOCK) && (vma->vm_flags & VM_LOCKED)) { > + if (page->mapping && trylock_page(page)) { > + lru_add_drain(); > + if (page->mapping) > + mlock_vma_page(page); > + unlock_page(page); > + } > + } Reviewed-by: Andrea Arcangeli Without the patch the kernel will be perfectly fine too, this is is only to show more "uptodate" values in meminfo. The meminfo would eventually go in sync as the vmscan started walking lrus and the old behavior will still happen when trylock fails. Without the patch the refiling events happen lazily as needed, now they happen even if they're not needed. In some ways we could drop this and also the 4k case and we'd overall improve performance. But transparent hugepages must behave identical to 4k pages, so unless we remove it from the 4k case, it's certainly good to apply the above. The patch can be deferred to 3.7 if needed. Thanks! Andrea -- 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