[PATCH] mm/mm_init.c: remove obsolete macro HASH_SMALL

From: Miaohe Lin
Date: Sat Jun 17 2023 - 03:10:37 EST


HASH_SMALL only works when parameter numentries is 0. But the sole caller
futex_init() never calls alloc_large_system_hash() with numentries set to
0. So HASH_SMALL is obsolete and remove it.

Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
include/linux/memblock.h | 2 --
kernel/futex/core.c | 3 +--
mm/mm_init.c | 10 +---------
3 files changed, 2 insertions(+), 13 deletions(-)

diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index f71ff9f0ec81..346d80809517 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -581,8 +581,6 @@ extern void *alloc_large_system_hash(const char *tablename,
unsigned long high_limit);

#define HASH_EARLY 0x00000001 /* Allocating during early boot? */
-#define HASH_SMALL 0x00000002 /* sub-page allocation allowed, min
- * shift passed via *_hash_shift */
#define HASH_ZERO 0x00000004 /* Zero allocated hash table */

/* Only NUMA needs hash distribution. 64bit NUMA architectures have
diff --git a/kernel/futex/core.c b/kernel/futex/core.c
index 514e4582b863..f10587d1d481 100644
--- a/kernel/futex/core.c
+++ b/kernel/futex/core.c
@@ -1132,8 +1132,7 @@ static int __init futex_init(void)
#endif

futex_queues = alloc_large_system_hash("futex", sizeof(*futex_queues),
- futex_hashsize, 0,
- futex_hashsize < 256 ? HASH_SMALL : 0,
+ futex_hashsize, 0, 0,
&futex_shift, NULL,
futex_hashsize, futex_hashsize);
futex_hashsize = 1UL << futex_shift;
diff --git a/mm/mm_init.c b/mm/mm_init.c
index d393631599a7..fab3c4649d5b 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -2492,15 +2492,7 @@ void *__init alloc_large_system_hash(const char *tablename,
else
numentries <<= (PAGE_SHIFT - scale);

- /* Make sure we've got at least a 0-order allocation.. */
- if (unlikely(flags & HASH_SMALL)) {
- /* Makes no sense without HASH_EARLY */
- WARN_ON(!(flags & HASH_EARLY));
- if (!(numentries >> *_hash_shift)) {
- numentries = 1UL << *_hash_shift;
- BUG_ON(!numentries);
- }
- } else if (unlikely((numentries * bucketsize) < PAGE_SIZE))
+ if (unlikely((numentries * bucketsize) < PAGE_SIZE))
numentries = PAGE_SIZE / bucketsize;
}
numentries = roundup_pow_of_two(numentries);
--
2.27.0