linux-kernel - [PATCH v2] mm/mm_init.c: remove obsolete macro HASH

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20230625021323.849147-1-linmiaohe@huawei.com>
Date:   Sun, 25 Jun 2023 10:13:23 +0800
From:   Miaohe Lin <linmiaohe@...wei.com>
To:     <akpm@...ux-foundation.org>, <rppt@...nel.org>,
        <tglx@...utronix.de>, <mingo@...hat.com>
CC:     <peterz@...radead.org>, <dvhart@...radead.org>,
        <dave@...olabs.net>, <andrealmeid@...lia.com>,
        <linux-mm@...ck.org>, <linux-kernel@...r.kernel.org>,
        <linmiaohe@...wei.com>
Subject: [PATCH v2] mm/mm_init.c: remove obsolete macro HASH_SMALL

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 So HASH_SMALL is obsolete and remove it.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@...wei.com>
---
v2:
  update HASH_ZERO to 0x2 per Mike
---
 include/linux/memblock.h |  4 +---
 kernel/futex/core.c      |  3 +--
 mm/mm_init.c             | 10 +---------
 3 files changed, 3 insertions(+), 14 deletions(-)

diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index f71ff9f0ec81..0d031fbfea25 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -581,9 +581,7 @@ 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 */
+#define HASH_ZERO	0x00000002	/* Zero allocated hash table */
 
 /* Only NUMA needs hash distribution. 64bit NUMA architectures have
  * sufficient vmalloc space.
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 a1963c3322af..999723dee8cc 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -2490,15 +2490,7 @@ 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