From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx117.postini.com [74.125.245.117]) by kanga.kvack.org (Postfix) with SMTP id 247EA6B002B for ; Fri, 24 Aug 2012 11:04:23 -0400 (EDT) Message-ID: <503797F0.1050805@redhat.com> Date: Fri, 24 Aug 2012 11:04:16 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [RFC] mm: support MIGRATE_DISCARD References: <1345782330-23234-1-git-send-email-minchan@kernel.org> In-Reply-To: <1345782330-23234-1-git-send-email-minchan@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim Cc: Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Marek Szyprowski , Michal Nazarewicz , Mel Gorman On 08/24/2012 12:25 AM, Minchan Kim wrote: > This patch introudes MIGRATE_DISCARD mode in migration. > It drops *unmapped clean cache pages* instead of migration so that Am I confused, or does the code not match the changelog? It looks like it is still trying to discard mapped page cache pages: > + file = page_is_file_cache(page); > + ttu_flags = TTU_IGNORE_ACCESS; > +retry: > + if (!(mode & MIGRATE_DISCARD) || !file || PageDirty(page)) > + ttu_flags |= (TTU_MIGRATION | TTU_IGNORE_MLOCK); > + else > + discard_mode = true; > + > /* Establish migration ptes or remove ptes */ > - try_to_unmap(page, TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS); > + rc = try_to_unmap(page, ttu_flags); > > skip_unmap: > - if (!page_mapped(page)) > - rc = move_to_new_page(newpage, page, remap_swapcache, mode); > + if (rc == SWAP_SUCCESS) { > + if (!discard_mode) > + rc = move_to_new_page(newpage, page, > + remap_swapcache, mode); > + else { > + > + rc = discard_page(page); > + goto uncharge; > + } -- All rights reversed -- 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