2017-03-10 04:38:05

by Wei Yang

[permalink] [raw]
Subject: [PATCH] mm/sparse: refine usemap_size() a little

Current implementation calculates usemap_size in two steps:
* calculate number of bytes to cover these bits
* calculate number of "unsigned long" to cover these bytes

It would be more clear by:
* calculate number of "unsigned long" to cover these bits
* multiple it with sizeof(unsigned long)

This patch refine usemap_size() a little to make it more easy to
understand.

Signed-off-by: Wei Yang <[email protected]>
---
mm/sparse.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/mm/sparse.c b/mm/sparse.c
index a0792526adfa..faa36ef9f9bd 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -249,10 +249,7 @@ static int __meminit sparse_init_one_section(struct mem_section *ms,

unsigned long usemap_size(void)
{
- unsigned long size_bytes;
- size_bytes = roundup(SECTION_BLOCKFLAGS_BITS, 8) / 8;
- size_bytes = roundup(size_bytes, sizeof(unsigned long));
- return size_bytes;
+ return BITS_TO_LONGS(SECTION_BLOCKFLAGS_BITS) * sizeof(unsigned long);
}

#ifdef CONFIG_MEMORY_HOTPLUG
--
2.11.0