From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 17 Apr 2006 09:18:30 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH 5/5] Swapless V2: Revise main migration logic Message-Id: <20060417091830.bca60006.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: References: <20060413235406.15398.42233.sendpatchset@schroedinger.engr.sgi.com> <20060413235432.15398.23912.sendpatchset@schroedinger.engr.sgi.com> <20060414101959.d59ac82d.kamezawa.hiroyu@jp.fujitsu.com> <20060414113455.15fd5162.kamezawa.hiroyu@jp.fujitsu.com> <20060415090639.dde469e8.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: akpm@osdl.org, hugh@veritas.com, linux-kernel@vger.kernel.org, lee.schermerhorn@hp.com, linux-mm@kvack.org, taka@valinux.co.jp, marcelo.tosatti@cyclades.com List-ID: On Sat, 15 Apr 2006 10:41:59 -0700 (PDT) Christoph Lameter wrote: > Note that there is an issue with your approach. If a migration entry is > copied during fork then SWP_MIGRATION_WRITE must become SWP_MIGRATION_READ > for some cases. Would you look into fixing this? > Thank you for pointing out the issue. In my understanding, copy_page_range() is used at fork(). This finally calls copy_one_pte() and copies ptes one by one. Maybe, I'll do like this. == 438 if (unlikely(!pte_present(pte)) { 439 if (!pte_file(pte)) { 440 swap_duplicate(pte_to_swp_entry(pte)); entry = pte_to_swp_entry(pte); #ifdef CONFIG_MIGRATION if (is_migration_entry(entry)) { ......always copy as MIGRATION_READ. } #endif 441 /* make sure dst_mm is on swapoff's mmlist. */ 442 if (unlikely(list_empty(&dst_mm->mmlist))) { 443 spin_lock(&mmlist_lock); 444 if (list_empty(&dst_mm->mmlist)) 445 list_add(&dst_mm->mmlist, 446 &src_mm->mmlist); 447 spin_unlock(&mmlist_lock); 448 } 449 } 450 goto out_set_pte; 451 } == Thanks, -Kame -- 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