Commit 5b760e64 authored Jul 31, 2012 by Gavin Shan Committed by Linus Torvalds Jul 31, 2012

mm/sparse: optimize sparse_index_alloc



With CONFIG_SPARSEMEM_EXTREME, the two levels of memory section
descriptors are allocated from slab or bootmem.  When allocating from
slab, let slab/bootmem allocator clear the memory chunk.  We needn't clear
it explicitly.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent b2145145

mm/sparse.c

+4 −6

Original line number	Diff line number	Diff line
		@@ -65,14 +65,12 @@ static struct mem_section noinline __init_refok *sparse_index_alloc(int nid)

		if (slab_is_available()) {
		if (node_state(nid, N_HIGH_MEMORY))
		section = kmalloc_node(array_size, GFP_KERNEL, nid);
		section = kzalloc_node(array_size, GFP_KERNEL, nid);
		else
		section = kmalloc(array_size, GFP_KERNEL);
		} else
		section = kzalloc(array_size, GFP_KERNEL);
		} else {
		section = alloc_bootmem_node(NODE_DATA(nid), array_size);

		if (section)
		memset(section, 0, array_size);
		}

		return section;
		}