From: Johannes Weiner Date: Tue, 10 Jan 2012 23:08:13 +0000 (-0800) Subject: mm: bootmem: drop superfluous range check when freeing pages in bulk X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=560a036b3a3733e33424385c0a0c799dee454d05;p=linux-beck.git mm: bootmem: drop superfluous range check when freeing pages in bulk The area node_bootmem_map represents is aligned to BITS_PER_LONG, and all bits in any aligned word of that map valid. When the represented area extends beyond the end of the node, the non-existant pages will be marked as reserved. As a result, when freeing a page block, doing an explicit range check for whether that block is within the node's range is redundant as the bitmap is consulted anyway to see whether all pages in the block are unreserved. Signed-off-by: Johannes Weiner Cc: Uwe Kleine-König Cc: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/mm/bootmem.c b/mm/bootmem.c index 3e6f152f117e..1aea171539ac 100644 --- a/mm/bootmem.c +++ b/mm/bootmem.c @@ -197,7 +197,7 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata) idx = start - bdata->node_min_pfn; vec = ~map[idx / BITS_PER_LONG]; - if (aligned && vec == ~0UL && start + BITS_PER_LONG <= end) { + if (aligned && vec == ~0UL) { int order = ilog2(BITS_PER_LONG); __free_pages_bootmem(pfn_to_page(start), order);