Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754108AbZGWLni (ORCPT ); Thu, 23 Jul 2009 07:43:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754050AbZGWLni (ORCPT ); Thu, 23 Jul 2009 07:43:38 -0400 Received: from mk-filter-3-a-1.mail.uk.tiscali.com ([212.74.100.54]:19257 "EHLO mk-filter-3-a-1.mail.uk.tiscali.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752608AbZGWLnh (ORCPT ); Thu, 23 Jul 2009 07:43:37 -0400 X-Trace: 231366300/mk-filter-3.mail.uk.tiscali.com/B2C/$b2c-THROTTLED-DYNAMIC/b2c-CUSTOMER-DYNAMIC-IP/79.69.32.187/None/hugh.dickins@tiscali.co.uk X-SBRS: None X-RemoteIP: 79.69.32.187 X-IP-MAIL-FROM: hugh.dickins@tiscali.co.uk X-SMTP-AUTH: X-MUA: X-IP-BHB: Once X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AsAEACvpZ0pPRSC7/2dsb2JhbACBUc8AgjKBWwU X-IronPort-AV: E=Sophos;i="4.43,254,1246834800"; d="scan'208";a="231366300" Date: Thu, 23 Jul 2009 12:43:25 +0100 (BST) From: Hugh Dickins X-X-Sender: hugh@sister.anvils To: KAMEZAWA Hiroyuki cc: Rik van Riel , Andrea Arcangeli , Izik Eidus , akpm@linux-foundation.org, chrisw@redhat.com, avi@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, nickpiggin@yahoo.com.au, Wu Fengguang Subject: Re: [PATCH 06/10] ksm: identify PageKsm pages In-Reply-To: <20090723110655.f08cdcdc.kamezawa.hiroyu@jp.fujitsu.com> Message-ID: References: <1247851850-4298-1-git-send-email-ieidus@redhat.com> <1247851850-4298-2-git-send-email-ieidus@redhat.com> <1247851850-4298-3-git-send-email-ieidus@redhat.com> <1247851850-4298-4-git-send-email-ieidus@redhat.com> <1247851850-4298-5-git-send-email-ieidus@redhat.com> <1247851850-4298-6-git-send-email-ieidus@redhat.com> <1247851850-4298-7-git-send-email-ieidus@redhat.com> <20090721175139.GE2239@random.random> <4A660101.3000307@redhat.com> <20090723110655.f08cdcdc.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1196 Lines: 32 On Thu, 23 Jul 2009, KAMEZAWA Hiroyuki wrote: > On Wed, 22 Jul 2009 13:54:06 +0100 (BST) > Hugh Dickins wrote: > > > > (At this instant I've forgotten why there's an unevictable list at > > all - somewhere in vmscan.c which is accustomed to dealing with > > pages on lists, so easier to have them on a list than not?) > > > I forget, too. But in short thinking, Unevictable pages should be > on LRU (marked as PG_lru) for isolating page (from LRU) called by > page migration etc. > > isolate_lru_page() > -> put page on private list > -> do some work > -> putback_lru_page() > > sequence is useful at handling pages in a list. > Because mlock/munclock can be called arbitrarily, unevicatable lru > works enough good for making above kinds of code simpler. Yes, I think that's it, thanks. And for the moment, the KSM pages are therefore unmigratable as well as unswappable; but that should change in 2.6.33. Hugh -- 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/