mirror of
https://github.com/openvswitch/ovs
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3c851001cb
The architecture-specific hash library automatically selects either jhash or CRC32 if it is available on the current processor. Signed-off-by: Jesse Gross <jesse@nicira.com>
52 lines
1.2 KiB
C
52 lines
1.2 KiB
C
/* General purpose hashing library
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*
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* That's a start of a kernel hashing library, which can be extended
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* with further algorithms in future. arch_fast_hash{2,}() will
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* eventually resolve to an architecture optimized implementation.
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*
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* Copyright 2013 Francesco Fusco <ffusco@redhat.com>
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* Copyright 2013 Daniel Borkmann <dborkman@redhat.com>
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* Copyright 2013 Thomas Graf <tgraf@redhat.com>
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* Licensed under the GNU General Public License, version 2.0 (GPLv2)
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*/
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#include <linux/version.h>
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#if LINUX_VERSION_CODE < KERNEL_VERSION(3,14,0)
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#include <linux/cache.h>
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#include <linux/compiler.h>
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#include <linux/jhash.h>
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#include <linux/hash.h>
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#include <linux/kernel.h>
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static struct fast_hash_ops arch_hash_ops __read_mostly = {
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.hash = jhash,
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.hash2 = jhash2,
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};
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static bool arch_inited __read_mostly;
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static void init_arch(void)
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{
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if (likely(arch_inited))
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return;
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setup_arch_fast_hash(&arch_hash_ops);
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arch_inited = true;
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}
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u32 arch_fast_hash(const void *data, u32 len, u32 seed)
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{
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init_arch();
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return arch_hash_ops.hash(data, len, seed);
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}
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u32 arch_fast_hash2(const u32 *data, u32 len, u32 seed)
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{
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init_arch();
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return arch_hash_ops.hash2(data, len, seed);
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}
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#endif /* < 3.14 */
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