From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 17 Mar 2006 17:20:22 +0900 From: Yasunori Goto Subject: [PATCH: 001/017]Memory hotplug for new nodes v.4.(Generic code of pgdat alloc) Message-Id: <20060317162642.C639.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: Andrew Morton Cc: "Luck, Tony" , Andi Kleen , Linux Kernel ML , linux-ia64@vger.kernel.org, linux-mm List-ID: This patch adds node-hot-add support to add_memory(). node hotadd uses this sequence. 1. allocate pgdat. 2. refresh NODE_DATA() 3. call free_area_init_node() to initialize 4. create sysfs entry 5. add memory (old add_memory()) 6. set node online 7. run kswapd for new node. (8). update zonelist after pages are onlined. (This is in other patch due to update phase is difference.) Note: To make common function as much as possible, there is 2 changes from v2. - The old add_memory(), which is defiend by each archs, is renamed to arch_add_memory(). New add_memory becomes caller of arch dependent function as a common code. - This patch changes add_memory()'s interface From: add_memory(start, end) TO : add_memory(nid, start, end). It was cause of similar code that finding node id from physical address is inside of old add_memory() on each arch. In addition, acpi memory hotplug driver can find node id easier. In v2, it must walk DSDT'S _CRS by matching physical address to get the handle of its memory device, then get _PXM and node id. Because input is just physical address. However, in v3, the acpi driver can use handle to get _PXM and node id for the new memory device. It can pass just node id to add_memory(). Fix interface of arch_add_memory() is in next patche. Signed-off-by: Yasunori Goto Signed-off-by: KAMEZAWA Hiroyuki include/linux/memory_hotplug.h | 3 + mm/memory_hotplug.c | 68 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 70 insertions(+), 1 deletion(-) Index: pgdat8/mm/memory_hotplug.c =================================================================== --- pgdat8.orig/mm/memory_hotplug.c 2006-03-17 15:40:27.000000000 +0900 +++ pgdat8/mm/memory_hotplug.c 2006-03-17 15:41:56.000000000 +0900 @@ -136,3 +136,71 @@ int online_pages(unsigned long pfn, unsi return 0; } + +static pg_data_t *hotadd_new_pgdat(int nid, u64 start) +{ + struct pglist_data *pgdat; + unsigned long zones_size[MAX_NR_ZONES] = {0}; + unsigned long zholes_size[MAX_NR_ZONES] = {0}; + unsigned long start_pfn = start >> PAGE_SHIFT; + + pgdat = arch_alloc_nodedata(nid); + if (!pgdat) + return NULL; + + arch_refresh_nodedata(nid, pgdat); + + /* we can use NODE_DATA(nid) from here */ + + /* init node's zones as empty zones, we don't have any present pages.*/ + free_area_init_node(nid, pgdat, zones_size, start_pfn, zholes_size); + + /* + * register this node to sysfs. + * this is depends on topology. So each arch has its own. + */ + arch_register_node(nid); + + return pgdat; +} + +static void rollback_node_hotadd(int nid, pg_data_t *pgdat) +{ + arch_refresh_nodedata(nid, NULL); + arch_free_nodedata(pgdat); + return; +} + +int add_memory(int nid, u64 start, u64 end) +{ + pg_data_t *pgdat = NULL; + int new_pgdat = 0; + int ret; + + if (!node_online(nid)) { + pgdat = hotadd_new_pgdat(nid, start); + if (!pgdat) + return -ENOMEM; + new_pgdat = 1; + ret = kswapd_run(nid); + if (ret) + goto error; + } + /* call arch's memory hotadd */ + ret = arch_add_memory(nid, start, end); + + if (!ret < 0) + goto error; + + /* we online node here. we have no error path from here. */ + node_set_online(nid); + + return ret; +error: + /* rollback pgdat allocation and others */ + if (new_pgdat) + rollback_node_hotadd(nid, pgdat); + + return ret; +} + Index: pgdat8/include/linux/memory_hotplug.h =================================================================== --- pgdat8.orig/include/linux/memory_hotplug.h 2006-03-17 15:40:27.000000000 +0900 +++ pgdat8/include/linux/memory_hotplug.h 2006-03-17 15:44:35.000000000 +0900 @@ -58,7 +58,8 @@ extern int add_one_highpage(struct page /* need some defines for these for archs that don't support it */ extern void online_page(struct page *page); /* VM interface that may be used by firmware interface */ -extern int add_memory(u64 start, u64 size); +extern int add_memory(int nid, u64 start, u64 size); +extern int arch_add_memory(int nid, u64 start, u64 size); extern int remove_memory(u64 start, u64 size); extern int online_pages(unsigned long, unsigned long); -- 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