Commit 98f3cfc1 authored by Yasunori Goto's avatar Yasunori Goto Committed by Linus Torvalds
Browse files

memory hotplug: Hot-add with sparsemem-vmemmap 



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.

Signed-off-by: default avatarYasunori Goto <y-goto@jp.fujitsu.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 48e94196

include/linux/mm.h

+1 −1
Original line number Diff line number Diff line
@@ -1147,7 +1147,7 @@ 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);

pgd_t *vmemmap_pgd_populate(unsigned long addr, int node);

pud_t *vmemmap_pud_populate(pgd_t *pgd, unsigned long addr, int node);

pmd_t *vmemmap_pmd_populate(pud_t *pud, unsigned long addr, int node);

mm/sparse-vmemmap.c

+1 −1
Original line number Diff line number Diff line
@@ -137,7 +137,7 @@ int __meminit vmemmap_populate_basepages(struct page *start_page, 
	return 0;

}



struct page __init *sparse_early_mem_map_populate(unsigned long pnum, int nid)

struct page * __meminit 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);

mm/sparse.c

+22 −3
Original line number Diff line number Diff line
@@ -259,7 +259,7 @@ static unsigned long *sparse_early_usemap_alloc(unsigned long pnum) 
}



#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_alloc(unsigned long pnum) 
	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 +322,18 @@ 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)

{

	/* This will make the necessary allocations eventually. */

	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 +356,12 @@ 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 +378,7 @@ static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages) 
		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 +401,7 @@ int sparse_add_one_section(struct zone *zone, unsigned long start_pfn, 
	 * 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);

CRA Git | Maintained and supported by SUSTech CRA and CCSE