Apart from call to sparse_index_init() during boot stage, the function
is mainly used for hotplug case as follows and protected by hotplug
mutex "mem_hotplug_mutex". So we needn't the spinlock in sparse_index_init().
sparse_index_init
sparse_add_one_section
__add_section
__add_pages
arch_add_memory
add_memory
Signed-off-by: Gavin Shan <shangw@xxxxxxxxxxxxxxxxxx>
---
mm/sparse.c | 14 +-------------
1 file changed, 1 insertion(+), 13 deletions(-)
diff --git a/mm/sparse.c b/mm/sparse.c
index 8b8edfb..4437c6c 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -77,7 +77,6 @@ static struct mem_section noinline __init_refok *sparse_index_alloc(int nid)
static int __meminit sparse_index_init(unsigned long section_nr, int nid)
{
- static DEFINE_SPINLOCK(index_init_lock);
unsigned long root = SECTION_NR_TO_ROOT(section_nr);
struct mem_section *section;
int ret = 0;
@@ -88,20 +87,9 @@ static int __meminit sparse_index_init(unsigned long section_nr, int nid)
section = sparse_index_alloc(nid);
if (!section)
return -ENOMEM;
- /*
- * This lock keeps two different sections from
- * reallocating for the same index
- */
- spin_lock(&index_init_lock);
-
- if (mem_section[root]) {
- ret = -EEXIST;
- goto out;
- }
mem_section[root] = section;
-out:
- spin_unlock(&index_init_lock);
+
return ret;
}
#else /* !SPARSEMEM_EXTREME */
--
1.7.9.5
--
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