From e76b63f80d938a1319eb5fb0ae7ea69bddfbae38 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Wed, 11 Sep 2013 14:22:17 -0700 Subject: memblock, numa: binary search node id Current early_pfn_to_nid() on arch that support memblock go over memblock.memory one by one, so will take too many try near the end. We can use existing memblock_search to find the node id for given pfn, that could save some time on bigger system that have many entries memblock.memory array. Here are the timing differences for several machines. In each case with the patch less time was spent in __early_pfn_to_nid(). 3.11-rc5 with patch difference (%) -------- ---------- -------------- UV1: 256 nodes 9TB: 411.66 402.47 -9.19 (2.23%) UV2: 255 nodes 16TB: 1141.02 1138.12 -2.90 (0.25%) UV2: 64 nodes 2TB: 128.15 126.53 -1.62 (1.26%) UV2: 32 nodes 2TB: 121.87 121.07 -0.80 (0.66%) Time in seconds. Signed-off-by: Yinghai Lu Cc: Tejun Heo Acked-by: Russ Anderson Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memblock.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'mm/memblock.c') diff --git a/mm/memblock.c b/mm/memblock.c index a847bfe6f3ba..0ac412a0a7ee 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -914,6 +914,24 @@ int __init_memblock memblock_is_memory(phys_addr_t addr) return memblock_search(&memblock.memory, addr) != -1; } +#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP +int __init_memblock memblock_search_pfn_nid(unsigned long pfn, + unsigned long *start_pfn, unsigned long *end_pfn) +{ + struct memblock_type *type = &memblock.memory; + int mid = memblock_search(type, (phys_addr_t)pfn << PAGE_SHIFT); + + if (mid == -1) + return -1; + + *start_pfn = type->regions[mid].base >> PAGE_SHIFT; + *end_pfn = (type->regions[mid].base + type->regions[mid].size) + >> PAGE_SHIFT; + + return type->regions[mid].nid; +} +#endif + /** * memblock_is_region_memory - check if a region is a subset of memory * @base: base of region to check -- cgit v1.2.3