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Subject[tip:x86/hash] x86, hash: Swap arguments passed to crc32_u32()
Commit-ID:  c5cdfdf90901c51363441365997eecd58efd9374
Gitweb: http://git.kernel.org/tip/c5cdfdf90901c51363441365997eecd58efd9374
Author: Jan Beulich <JBeulich@suse.com>
AuthorDate: Thu, 27 Feb 2014 08:47:34 +0000
Committer: H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 19 Mar 2014 16:51:04 -0700

x86, hash: Swap arguments passed to crc32_u32()

... to match the function's parameters. While reportedly commutative,
using the proper order allows for leveraging the instruction permitting
the source operand to be in memory.

[ hpa: This code originated in the dpdk toolkit. This was a bug in dpdk
which has recently been fixed in part due to an earlier version of
this patch. ]

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/530F09B6020000780011FBEB@nat28.tlf.novell.com
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Francesco Fusco <ffusco@redhat.com>
Cc: Thomas Graf <tgraf@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
arch/x86/lib/hash.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/x86/lib/hash.c b/arch/x86/lib/hash.c
index 060cc44..ac628aa 100644
--- a/arch/x86/lib/hash.c
+++ b/arch/x86/lib/hash.c
@@ -53,7 +53,7 @@ static u32 intel_crc4_2_hash(const void *data, u32 len, u32 seed)
u32 i, tmp = 0;

for (i = 0; i < len / 4; i++)
- seed = crc32_u32(*p32++, seed);
+ seed = crc32_u32(seed, *p32++);

switch (3 - (len & 0x03)) {
case 0:
@@ -64,7 +64,7 @@ static u32 intel_crc4_2_hash(const void *data, u32 len, u32 seed)
/* fallthrough */
case 2:
tmp |= *((const u8 *) p32);
- seed = crc32_u32(tmp, seed);
+ seed = crc32_u32(seed, tmp);
default:
break;
}
@@ -78,7 +78,7 @@ static u32 intel_crc4_2_hash2(const u32 *data, u32 len, u32 seed)
u32 i;

for (i = 0; i < len; i++)
- seed = crc32_u32(*p32++, seed);
+ seed = crc32_u32(seed, *p32++);

return seed;
}

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