From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 17 Aug 2007 16:08:35 +0900 From: Yasunori Goto Subject: [Patch](memory hotplug) Hot-add with sparsemem-vmemmap Message-Id: <20070817155908.7D91.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: Andy Whitcroft , Andrew Morton , Christoph Lameter , Mel Gorman Cc: linux-mm List-ID: Hello. This patch is to avoid panic when memory hot-add is executed with sparsemem-vmemmap. Current vmemmap-sparsemem code doesn't support memory hot-add. Vmemmap must be populated when hot-add. This is for 2.6.23-rc2-mm2. Todo: # Even if this patch is applied, the message "[xxxx-xxxx] potential offnode page_structs" is displayed. To allocate memmap on its node, memmap (and pgdat) must be initialized itself like chicken and egg relationship. # vmemmap_unpopulate will be necessary for followings. - For cancel hot-add due to error. - For unplug. Please comment. Signed-off-by: Yasunori Goto --- include/linux/mm.h | 2 +- mm/sparse-vmemmap.c | 2 +- mm/sparse.c | 24 +++++++++++++++++++++--- 3 files changed, 23 insertions(+), 5 deletions(-) Index: vmemmap/mm/sparse-vmemmap.c =================================================================== --- vmemmap.orig/mm/sparse-vmemmap.c 2007-08-10 20:17:19.000000000 +0900 +++ vmemmap/mm/sparse-vmemmap.c 2007-08-10 21:12:54.000000000 +0900 @@ -170,7 +170,7 @@ int __meminit vmemmap_populate(struct pa } #endif /* !CONFIG_ARCH_POPULATES_SPARSEMEM_VMEMMAP */ -struct page __init *sparse_early_mem_map_populate(unsigned long pnum, int nid) +struct page *sparse_mem_map_populate(unsigned long pnum, int nid) { struct page *map = pfn_to_page(pnum * PAGES_PER_SECTION); int error = vmemmap_populate(map, PAGES_PER_SECTION, nid); Index: vmemmap/include/linux/mm.h =================================================================== --- vmemmap.orig/include/linux/mm.h 2007-08-10 20:17:19.000000000 +0900 +++ vmemmap/include/linux/mm.h 2007-08-10 21:06:34.000000000 +0900 @@ -1146,7 +1146,7 @@ extern int randomize_va_space; const char * arch_vma_name(struct vm_area_struct *vma); -struct page *sparse_early_mem_map_populate(unsigned long pnum, int nid); +struct page *sparse_mem_map_populate(unsigned long pnum, int nid); int vmemmap_populate(struct page *start_page, unsigned long pages, int node); int vmemmap_populate_pmd(pud_t *, unsigned long, unsigned long, int); void *vmemmap_alloc_block(unsigned long size, int node); Index: vmemmap/mm/sparse.c =================================================================== --- vmemmap.orig/mm/sparse.c 2007-08-10 20:17:19.000000000 +0900 +++ vmemmap/mm/sparse.c 2007-08-10 21:21:01.000000000 +0900 @@ -259,7 +259,7 @@ static unsigned long *sparse_early_usema } #ifndef CONFIG_SPARSEMEM_VMEMMAP -struct page __init *sparse_early_mem_map_populate(unsigned long pnum, int nid) +struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid) { struct page *map; @@ -284,7 +284,7 @@ struct page __init *sparse_early_mem_map struct mem_section *ms = __nr_to_section(pnum); int nid = sparse_early_nid(ms); - map = sparse_early_mem_map_populate(pnum, nid); + map = sparse_mem_map_populate(pnum, nid); if (map) return map; @@ -322,6 +322,17 @@ void __init sparse_init(void) } #ifdef CONFIG_MEMORY_HOTPLUG +#ifdef CONFIG_SPARSEMEM_VMEMMAP +static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid, + unsigned long nr_pages) +{ + return sparse_mem_map_populate(pnum, nid); +} +static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages) +{ + return; /* XXX: Not implemented yet */ +} +#else static struct page *__kmalloc_section_memmap(unsigned long nr_pages) { struct page *page, *ret; @@ -344,6 +355,12 @@ got_map_ptr: return ret; } +static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid, + unsigned long nr_pages) +{ + return __kmalloc_section_memmap(nr_pages); +} + static int vaddr_in_vmalloc_area(void *addr) { if (addr >= (void *)VMALLOC_START && @@ -360,6 +377,7 @@ static void __kfree_section_memmap(struc free_pages((unsigned long)memmap, get_order(sizeof(struct page) * nr_pages)); } +#endif /* CONFIG_SPARSEMEM_VMEMMAP */ /* * returns the number of sections whose mem_maps were properly @@ -382,7 +400,7 @@ int sparse_add_one_section(struct zone * * plus, it does a kmalloc */ sparse_index_init(section_nr, pgdat->node_id); - memmap = __kmalloc_section_memmap(nr_pages); + memmap = kmalloc_section_memmap(section_nr, pgdat->node_id, nr_pages); usemap = __kmalloc_section_usemap(); pgdat_resize_lock(pgdat, &flags); -- 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