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    SubjectRe: [PATCH] crypto: twofish - add x86_64/avx assembler implementation
    Quoting Borislav Petkov <bp@alien8.de>:

    > On Wed, Aug 15, 2012 at 11:42:16AM +0300, Jussi Kivilinna wrote:
    >> I started thinking about the performance on AMD Bulldozer.
    >> vmovq/vmovd/vpextr*/vpinsr* between FPU and general purpose registers
    >> on AMD CPU is alot slower (latencies from 8 to 12 cycles) than on
    >> Intel sandy-bridge (where instructions have latency of 1 to 2). See:
    >> http://www.agner.org/optimize/instruction_tables.pdf
    >>
    >> It would be really good, if implementation could be tested on AMD CPU
    >> to determinate, if it causes performance regression. However I don't
    >> have access to machine with such CPU.
    >
    > But I do. :)
    >
    > And if you tell me exactly how to run the tests and on what kernel, I'll
    > try to do so.
    >

    Twofish-avx (CONFIG_TWOFISH_AVX_X86_64) is available in 3.6-rc1. For
    testing you need CRYPTO_TEST build as module. You should turn off
    turbo-core, freq-scaling, etc.

    Testing twofish-avx ('async twofish' speed test):
    modprobe twofish-avx-x86_64
    modprobe tcrypt mode=504 sec=1

    Testing twofish-x86_64-3way ('sync twofish' speed test):
    modprobe twofish-x86_64-3way
    modprobe tcrypt mode=202 sec=1

    Loading tcrypt will block until tests are complete, after which
    modprobe will return with error. This is expected. Results are in
    kernel log.

    -Jussi

    > HTH.
    >
    > --
    > Regards/Gruss,
    > Boris.
    >
    >





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