Messages in this thread Patch in this message | | | Date | Wed, 10 May 2006 11:51:02 +0100 | Subject | [PATCH] sparsemem record nid during memory present | From | Andy Whitcroft <> |
| |
Ok, here is the updated version. Better commentry on what we are doing and how long the data is kept (suggested by Dave Hansen). Also added a SECTION_NID_SHIFT to better describe its use. This showed a small buglett as we were shifting by 4 (1<<2) instead of 2; now fixed.
-apw === 8< === sparsemem record nid during memory present
Record the node id as we mark sections for instantiation. Use this nid during instantiation to direct allocations.
Signed-off-by: Andy Whitcroft <apw@shadowen.org> --- include/linux/mmzone.h | 5 +++++ mm/sparse.c | 22 ++++++++++++++++++++-- 2 files changed, 25 insertions(+), 2 deletions(-) diff -upN reference/include/linux/mmzone.h current/include/linux/mmzone.h --- reference/include/linux/mmzone.h +++ current/include/linux/mmzone.h @@ -508,6 +508,10 @@ struct mem_section { * pages. However, it is stored with some other magic. * (see sparse.c::sparse_init_one_section()) * + * Additionally during early boot we encode node id of + * the location of the section here to guide allocation. + * (see sparse.c::memory_present()) + * * Making it a UL at least makes someone do a cast * before using it wrong. */ @@ -547,6 +551,7 @@ extern int __section_nr(struct mem_secti #define SECTION_HAS_MEM_MAP (1UL<<1) #define SECTION_MAP_LAST_BIT (1UL<<2) #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1)) +#define SECTION_NID_SHIFT 2 static inline struct page *__section_mem_map_addr(struct mem_section *section) { diff -upN reference/mm/sparse.c current/mm/sparse.c --- reference/mm/sparse.c +++ current/mm/sparse.c @@ -102,6 +102,22 @@ int __section_nr(struct mem_section* ms) return (root_nr * SECTIONS_PER_ROOT) + (ms - root); } +/* + * During early boot, before section_mem_map is used for an actual + * mem_map, we use section_mem_map to store the section's NUMA + * node. This keeps us from having to use another data structure. The + * node information is cleared just before we store the real mem_map. + */ +static inline unsigned long sparse_encode_early_nid(int nid) +{ + return (nid << SECTION_NID_SHIFT); +} + +static inline int sparse_early_nid(struct mem_section *section) +{ + return (section->section_mem_map >> SECTION_NID_SHIFT); +} + /* Record a memory area against a node. */ void memory_present(int nid, unsigned long start, unsigned long end) { @@ -116,7 +132,8 @@ void memory_present(int nid, unsigned lo ms = __nr_to_section(section); if (!ms->section_mem_map) - ms->section_mem_map = SECTION_MARKED_PRESENT; + ms->section_mem_map = sparse_encode_early_nid(nid) | + SECTION_MARKED_PRESENT; } } @@ -167,6 +184,7 @@ static int sparse_init_one_section(struc if (!valid_section(ms)) return -EINVAL; + ms->section_mem_map &= ~SECTION_MAP_MASK; ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum); return 1; @@ -175,8 +193,8 @@ static int sparse_init_one_section(struc static struct page *sparse_early_mem_map_alloc(unsigned long pnum) { struct page *map; - int nid = early_pfn_to_nid(section_nr_to_pfn(pnum)); struct mem_section *ms = __nr_to_section(pnum); + int nid = sparse_early_nid(ms); map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION); if (map) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |