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| author | Michael Hennerich <michael.hennerich@analog.com> | 2009-02-04 16:49:45 +0800 |
|---|---|---|
| committer | Bryan Wu <cooloney@kernel.org> | 2009-02-04 16:49:45 +0800 |
| commit | aa9c33b496ca9434f26beaa1b447a6e2e5d8ad6a (patch) | |
| tree | c47851ad65934ed0a3825902673173451d098780 /arch/blackfin/include | |
| parent | 0ce5eaf8ec156926a29313de877d9d5e0a692054 (diff) | |
| download | linux-aa9c33b496ca9434f26beaa1b447a6e2e5d8ad6a.tar.bz2 | |
Blackfin arch: Faster Implementation of csum_tcpudp_nofold()
Avoid conditional branch instructions during carry bit additions.
Special thanks to Bernd.
Simplify: Use ((len + proto) << 8) like every other __LITTLE_ENDIAN__ machine
Cc: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Diffstat (limited to 'arch/blackfin/include')
| -rw-r--r-- | arch/blackfin/include/asm/checksum.h | 34 |
1 files changed, 17 insertions, 17 deletions
diff --git a/arch/blackfin/include/asm/checksum.h b/arch/blackfin/include/asm/checksum.h index f67289a0d8d2..793581fc9556 100644 --- a/arch/blackfin/include/asm/checksum.h +++ b/arch/blackfin/include/asm/checksum.h @@ -63,23 +63,23 @@ static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len, unsigned short proto, __wsum sum) { - - __asm__ ("%0 = %0 + %1;\n\t" - "CC = AC0;\n\t" - "if !CC jump 4;\n\t" - "%0 = %0 + %4;\n\t" - "%0 = %0 + %2;\n\t" - "CC = AC0;\n\t" - "if !CC jump 4;\n\t" - "%0 = %0 + %4;\n\t" - "%0 = %0 + %3;\n\t" - "CC = AC0;\n\t" - "if !CC jump 4;\n\t" - "%0 = %0 + %4;\n\t" - "NOP;\n\t" - : "=d" (sum) - : "d" (daddr), "d" (saddr), "d" ((ntohs(len)<<16)+proto*256), "d" (1), "0"(sum) - : "CC"); + unsigned int carry; + + __asm__ ("%0 = %0 + %2;\n\t" + "CC = AC0;\n\t" + "%1 = CC;\n\t" + "%0 = %0 + %1;\n\t" + "%0 = %0 + %3;\n\t" + "CC = AC0;\n\t" + "%1 = CC;\n\t" + "%0 = %0 + %1;\n\t" + "%0 = %0 + %4;\n\t" + "CC = AC0;\n\t" + "%1 = CC;\n\t" + "%0 = %0 + %1;\n\t" + : "=d" (sum), "=&d" (carry) + : "d" (daddr), "d" (saddr), "d" ((len + proto) << 8), "0"(sum) + : "CC"); return (sum); } |