From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 19 Jun 2007 17:49:12 +0100 Subject: Re: [PATCH 5/7] Introduce a means of compacting memory within a zone Message-ID: <20070619164912.GE17109@skynet.ie> References: <20070618092821.7790.52015.sendpatchset@skynet.skynet.ie> <20070618093002.7790.68471.sendpatchset@skynet.skynet.ie> <20070619213927.AC83.Y-GOTO@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20070619213927.AC83.Y-GOTO@jp.fujitsu.com> From: mel@skynet.ie (Mel Gorman) Sender: owner-linux-mm@kvack.org Return-Path: To: Yasunori Goto Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, kamezawa.hiroyu@jp.fujitsu.com, clameter@sgi.com List-ID: On (19/06/07 21:54), Yasunori Goto didst pronounce: > Hi Mel-san. > This is very interesting feature. > > Now, I'm testing your patches. > > > +static int isolate_migratepages(struct zone *zone, > > + struct compact_control *cc) > > +{ > > + unsigned long high_pfn, low_pfn, end_pfn, start_pfn; > > (snip) > > > + /* Time to isolate some pages for migration */ > > + spin_lock_irq(&zone->lru_lock); > > + for (; low_pfn < end_pfn; low_pfn++) { > > + if (!pfn_valid_within(low_pfn)) > > + continue; > > + > > + /* Get the page and skip if free */ > > + page = pfn_to_page(low_pfn); > > I met panic at here on my tiger4. > How annoying. > I compiled with CONFIG_SPARSEMEM. So, CONFIG_HOLES_IN_ZONE is not set. > pfn_valid_within() returns 1 every time on this configuration. As it should. > (This config is for only virtual memmap) > But, my tiger4 box has memory holes in normal zone. > > When it is changed to normal pfn_valid(), no panic occurs. > It's because I never check if the MAX_ORDER block is valid before isolating. This needs to be implemented just like what isolate_freepages() and isolate_freepages_block() does. Change it to pfn_valid() for the moment and I'll have this one fixed up properly in the next version. > Hmmm. > > Bye. Thanks for testing. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- 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