Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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>
authored by
Joern Engel
and committed by
Linus Torvalds
8df3aaaf
fed8f509
+6
-4
+6
-4
lib/btree.c
+6
-4
lib/btree.c
···
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*
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* As should be obvious for Linux kernel code, license is GPLv2
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*
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-
* Copyright (c) 2007-2008 Joern Engel <joern@logfs.org>
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+
* Copyright (c) 2007-2008 Joern Engel <joern@purestorage.com>
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* Bits and pieces stolen from Peter Zijlstra's code, which is
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* Copyright 2007, Red Hat Inc. Peter Zijlstra
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* GPLv2
···
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.no_longs = 2 * LONG_PER_U64 * (NODESIZE / sizeof(long) / (1 + 2 * LONG_PER_U64)),
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};
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EXPORT_SYMBOL_GPL(btree_geo128);
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+
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#define MAX_KEYLEN (2 * LONG_PER_U64)
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static struct kmem_cache *btree_cachep;
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···
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{
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int i, height;
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unsigned long *node, *oldnode;
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-
unsigned long *retry_key = NULL, key[geo->keylen];
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unsigned long *retry_key = NULL, key[MAX_KEYLEN];
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if (keyzero(geo, __key))
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return NULL;
···
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int btree_merge(struct btree_head *target, struct btree_head *victim,
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struct btree_geo *geo, gfp_t gfp)
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{
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-
unsigned long key[geo->keylen];
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unsigned long dup[geo->keylen];
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+
unsigned long key[MAX_KEYLEN];
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unsigned long dup[MAX_KEYLEN];
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void *val;
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int err;
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