From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sat, 07 Jan 2006 11:50:38 +0900 From: Yasunori Goto Subject: Re: [PATCH] Simple memory hot-add for ia64. In-Reply-To: <1136575296.8189.25.camel@localhost.localdomain> References: <20060106114249.5649.Y-GOTO@jp.fujitsu.com> <1136575296.8189.25.camel@localhost.localdomain> Message-Id: <20060107114233.120C.Y-GOTO@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: Dave Hansen , "Luck, Tony" Cc: Linux Hotplug Memory Support , linux-ia64@vger.kernel.org, Linux Kernel ML , linux-mm , Bob Picco , Mike Kravetz List-ID: > On Fri, 2006-01-06 at 11:50 +0900, Yasunori Goto wrote: > > Fortunately, 2.6.15 includes memory hot-add function for i386 and ppc. > > So, I made a patch for ia64. > > This doesn't make new pgdat. All of new memory will belong to > > node 0 by this patch. But this is simplest first step and best start for > > future work. > > It does look quite simple. Nice work. > > > +#ifdef CONFIG_MEMORY_HOTPLUG > > +void online_page(struct page *page) > > +{ > > + ClearPageReserved(page); > > + set_page_count(page, 1); > > + __free_page(page); > > + totalram_pages++; > > + num_physpages++; > > +} > > You're the first one to get one of these in for an alternate > architecture. We'll need to keep an eye out so that one of these > doesn't pop up on each of the 64-bit arches with no highmem as we add > support. But, this should be just fine for now. > > > +int add_memory(u64 start, u64 size) > > +{ > > + pg_data_t *pgdat; > > + struct zone *zone; > > + unsigned long start_pfn = start >> PAGE_SHIFT; > > + unsigned long nr_pages = size >> PAGE_SHIFT; > > + int ret; > > + > > + pgdat = NODE_DATA(0); > > + > > + zone = pgdat->node_zones + ZONE_NORMAL; > > + ret = __add_pages(zone, start_pfn, nr_pages); > > + > > + if (ret) > > + printk("%s: Problem encountered in __add_pages() as ret=%d\n", __func__, ret); > > For some reason, I thought we were officially supposed to use > __FUNCTION__ for stuff like this. However, I am usually lazy in my > debugging patches and use __func__. I'm a bad example. I didn't know it. Thanks! > This also looks a bit past 80 columns. Ok. This is newer one. :-) Bye. ------------------ Fortunately, 2.6.15 includes memory hot-add function for i386 and ppc. So, I made a patch for ia64. This doesn't make new pgdat. All of new memory will belong to node 0 by this patch. But this is simplest first step and best start for future work. I tested on my Tiger4. Please apply. (This patch doesn't use ZONE_EASY_RECLAIM yet, because its zone will be useful for just hot-remove.) Signed-off-by: Yasunori Goto Index: new_feature_patch/arch/ia64/mm/init.c =================================================================== --- new_feature_patch.orig/arch/ia64/mm/init.c 2006-01-07 10:58:27.000000000 +0900 +++ new_feature_patch/arch/ia64/mm/init.c 2006-01-07 10:59:52.000000000 +0900 @@ -635,3 +635,39 @@ mem_init (void) ia32_mem_init(); #endif } + +#ifdef CONFIG_MEMORY_HOTPLUG +void online_page(struct page *page) +{ + ClearPageReserved(page); + set_page_count(page, 1); + __free_page(page); + totalram_pages++; + num_physpages++; +} + +int add_memory(u64 start, u64 size) +{ + pg_data_t *pgdat; + struct zone *zone; + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + int ret; + + pgdat = NODE_DATA(0); + + zone = pgdat->node_zones + ZONE_NORMAL; + ret = __add_pages(zone, start_pfn, nr_pages); + + if (ret) + printk("%s: Problem encountered in __add_pages() as ret=%d\n", + __FUNCTION__, ret); + + return ret; +} + +int remove_memory(u64 start, u64 size) +{ + return -EINVAL; +} +#endif -- Yasunori Goto -- 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