mm: bootmem: drop superfluous range check when freeing pages in bulk
authorJohannes Weiner <hannes@cmpxchg.org>
Tue, 10 Jan 2012 23:08:13 +0000 (15:08 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 11 Jan 2012 00:30:44 +0000 (16:30 -0800)
commit560a036b3a3733e33424385c0a0c799dee454d05
tree07d1ddc729e233d0590b308f1ea7d04405e796b6
parentc3993076f842de3754360e5b998d6657a9d30303
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 <hannes@cmpxchg.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/bootmem.c