mirror of
https://github.com/torvalds/linux.git
synced 2024-11-07 04:32:03 +00:00
7a5917e978
Minor cleanups: - simplify switch statement - add __init annotation to setup_arch_fast_hash() Signed-off-by: Jan Beulich <jbeulich@suse.com> Link: http://lkml.kernel.org/r/530F09CE020000780011FBEF@nat28.tlf.novell.com Cc: Francesco Fusco <ffusco@redhat.com> Cc: Thomas Graf <tgraf@redhat.com> Cc: David S. Miller <davem@davemloft.net> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
93 lines
2.8 KiB
C
93 lines
2.8 KiB
C
/*
|
|
* Some portions derived from code covered by the following notice:
|
|
*
|
|
* Copyright (c) 2010-2013 Intel Corporation. All rights reserved.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* * Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* * Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in
|
|
* the documentation and/or other materials provided with the
|
|
* distribution.
|
|
* * Neither the name of Intel Corporation nor the names of its
|
|
* contributors may be used to endorse or promote products derived
|
|
* from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <linux/hash.h>
|
|
#include <linux/init.h>
|
|
|
|
#include <asm/processor.h>
|
|
#include <asm/cpufeature.h>
|
|
#include <asm/hash.h>
|
|
|
|
static inline u32 crc32_u32(u32 crc, u32 val)
|
|
{
|
|
#ifdef CONFIG_AS_CRC32
|
|
asm ("crc32l %1,%0\n" : "+r" (crc) : "rm" (val));
|
|
#else
|
|
asm (".byte 0xf2, 0x0f, 0x38, 0xf1, 0xc1" : "+a" (crc) : "c" (val));
|
|
#endif
|
|
return crc;
|
|
}
|
|
|
|
static u32 intel_crc4_2_hash(const void *data, u32 len, u32 seed)
|
|
{
|
|
const u32 *p32 = (const u32 *) data;
|
|
u32 i, tmp = 0;
|
|
|
|
for (i = 0; i < len / 4; i++)
|
|
seed = crc32_u32(seed, *p32++);
|
|
|
|
switch (len & 3) {
|
|
case 3:
|
|
tmp |= *((const u8 *) p32 + 2) << 16;
|
|
/* fallthrough */
|
|
case 2:
|
|
tmp |= *((const u8 *) p32 + 1) << 8;
|
|
/* fallthrough */
|
|
case 1:
|
|
tmp |= *((const u8 *) p32);
|
|
seed = crc32_u32(seed, tmp);
|
|
break;
|
|
}
|
|
|
|
return seed;
|
|
}
|
|
|
|
static u32 intel_crc4_2_hash2(const u32 *data, u32 len, u32 seed)
|
|
{
|
|
const u32 *p32 = (const u32 *) data;
|
|
u32 i;
|
|
|
|
for (i = 0; i < len; i++)
|
|
seed = crc32_u32(seed, *p32++);
|
|
|
|
return seed;
|
|
}
|
|
|
|
void __init setup_arch_fast_hash(struct fast_hash_ops *ops)
|
|
{
|
|
if (cpu_has_xmm4_2) {
|
|
ops->hash = intel_crc4_2_hash;
|
|
ops->hash2 = intel_crc4_2_hash2;
|
|
}
|
|
}
|