diff options
| -rw-r--r-- | drivers/base/memory.c | 4 | ||||
| -rw-r--r-- | include/linux/mmzone.h | 2 | ||||
| -rw-r--r-- | mm/sparse.c | 60 |
3 files changed, 52 insertions, 14 deletions
diff --git a/drivers/base/memory.c b/drivers/base/memory.c index cc4f1d0cbffe..90225ffee501 100644 --- a/drivers/base/memory.c +++ b/drivers/base/memory.c @@ -820,6 +820,10 @@ int __init memory_dev_init(void) */ mutex_lock(&mem_sysfs_mutex); for (i = 0; i < NR_MEM_SECTIONS; i += sections_per_block) { + /* Don't iterate over sections we know are !present: */ + if (i > __highest_present_section_nr) + break; + err = add_memory_block(i); if (!ret) ret = err; diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index ef6a13b7bd3e..fc39f85d273c 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -1180,6 +1180,8 @@ static inline struct mem_section *__pfn_to_section(unsigned long pfn) return __nr_to_section(pfn_to_section_nr(pfn)); } +extern int __highest_present_section_nr; + #ifndef CONFIG_HAVE_ARCH_PFN_VALID static inline int pfn_valid(unsigned long pfn) { diff --git a/mm/sparse.c b/mm/sparse.c index 6903c8fc3085..5032c9a619de 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -168,6 +168,44 @@ void __meminit mminit_validate_memmodel_limits(unsigned long *start_pfn, } } +/* + * There are a number of times that we loop over NR_MEM_SECTIONS, + * looking for section_present() on each. But, when we have very + * large physical address spaces, NR_MEM_SECTIONS can also be + * very large which makes the loops quite long. + * + * Keeping track of this gives us an easy way to break out of + * those loops early. + */ +int __highest_present_section_nr; +static void section_mark_present(struct mem_section *ms) +{ + int section_nr = __section_nr(ms); + + if (section_nr > __highest_present_section_nr) + __highest_present_section_nr = section_nr; + + ms->section_mem_map |= SECTION_MARKED_PRESENT; +} + +static inline int next_present_section_nr(int section_nr) +{ + do { + section_nr++; + if (present_section_nr(section_nr)) + return section_nr; + } while ((section_nr < NR_MEM_SECTIONS) && + (section_nr <= __highest_present_section_nr)); + + return -1; +} +#define for_each_present_section_nr(start, section_nr) \ + for (section_nr = next_present_section_nr(start-1); \ + ((section_nr >= 0) && \ + (section_nr < NR_MEM_SECTIONS) && \ + (section_nr <= __highest_present_section_nr)); \ + section_nr = next_present_section_nr(section_nr)) + /* Record a memory area against a node. */ void __init memory_present(int nid, unsigned long start, unsigned long end) { @@ -183,9 +221,10 @@ void __init memory_present(int nid, unsigned long start, unsigned long end) set_section_nid(section, nid); ms = __nr_to_section(section); - if (!ms->section_mem_map) - ms->section_mem_map = sparse_encode_early_nid(nid) | - SECTION_MARKED_PRESENT; + if (!ms->section_mem_map) { + ms->section_mem_map = sparse_encode_early_nid(nid); + section_mark_present(ms); + } } } @@ -476,23 +515,19 @@ static void __init alloc_usemap_and_memmap(void (*alloc_func) int nodeid_begin = 0; unsigned long pnum_begin = 0; - for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) { + for_each_present_section_nr(0, pnum) { struct mem_section *ms; - if (!present_section_nr(pnum)) - continue; ms = __nr_to_section(pnum); nodeid_begin = sparse_early_nid(ms); pnum_begin = pnum; break; } map_count = 1; - for (pnum = pnum_begin + 1; pnum < NR_MEM_SECTIONS; pnum++) { + for_each_present_section_nr(pnum_begin + 1, pnum) { struct mem_section *ms; int nodeid; - if (!present_section_nr(pnum)) - continue; ms = __nr_to_section(pnum); nodeid = sparse_early_nid(ms); if (nodeid == nodeid_begin) { @@ -561,10 +596,7 @@ void __init sparse_init(void) (void *)map_map); #endif - for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) { - if (!present_section_nr(pnum)) - continue; - + for_each_present_section_nr(0, pnum) { usemap = usemap_map[pnum]; if (!usemap) continue; @@ -722,7 +754,7 @@ int __meminit sparse_add_one_section(struct zone *zone, unsigned long start_pfn) memset(memmap, 0, sizeof(struct page) * PAGES_PER_SECTION); - ms->section_mem_map |= SECTION_MARKED_PRESENT; + section_mark_present(ms); ret = sparse_init_one_section(ms, section_nr, memmap, usemap); |