diff options
| author | Joern Engel | 2018-03-13 11:36:49 -0700 |
|---|---|---|
| committer | Linus Torvalds | 2018-03-14 16:55:29 -0700 |
| commit | 8df3aaaf9b5f8bdfc4036695fa22f35b45b4d92f (patch) | |
| tree | 159410afc5a8b37d2026d367fb570d10ff2e98bd | |
| parent | fed8f5090ca647b7cf37c21f92053e517526133a (diff) | |
btree: avoid variable-length allocations
geo->keylen cannot be larger than 4. So we might as well make
fixed-size allocations.
Given the one remaining user, geo->keylen cannot even be larger than 1.
Logfs used to have 64bit and 128bit keys, tcm_qla2xxx only has 32bit
keys. But let's not break the code if we don't have to.
Signed-off-by: Joern Engel <joern@purestorage.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | lib/btree.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/lib/btree.c b/lib/btree.c index f93a945274af..590facba2c50 100644 --- a/lib/btree.c +++ b/lib/btree.c @@ -3,7 +3,7 @@ * * As should be obvious for Linux kernel code, license is GPLv2 * - * Copyright (c) 2007-2008 Joern Engel <joern@logfs.org> + * Copyright (c) 2007-2008 Joern Engel <joern@purestorage.com> * Bits and pieces stolen from Peter Zijlstra's code, which is * Copyright 2007, Red Hat Inc. Peter Zijlstra * GPLv2 @@ -76,6 +76,8 @@ struct btree_geo btree_geo128 = { }; EXPORT_SYMBOL_GPL(btree_geo128); +#define MAX_KEYLEN (2 * LONG_PER_U64) + static struct kmem_cache *btree_cachep; void *btree_alloc(gfp_t gfp_mask, void *pool_data) @@ -313,7 +315,7 @@ void *btree_get_prev(struct btree_head *head, struct btree_geo *geo, { int i, height; unsigned long *node, *oldnode; - unsigned long *retry_key = NULL, key[geo->keylen]; + unsigned long *retry_key = NULL, key[MAX_KEYLEN]; if (keyzero(geo, __key)) return NULL; @@ -639,8 +641,8 @@ EXPORT_SYMBOL_GPL(btree_remove); int btree_merge(struct btree_head *target, struct btree_head *victim, struct btree_geo *geo, gfp_t gfp) { - unsigned long key[geo->keylen]; - unsigned long dup[geo->keylen]; + unsigned long key[MAX_KEYLEN]; + unsigned long dup[MAX_KEYLEN]; void *val; int err; |