Eric Lee / smarc-fsl-linux-kernel

01 Dec, 2015

1 commit

  • dc4fbba11   powerpc: Create disable_kernel_{fp,altivec,vsx,spe}() ... Browse Code »

    The enable_kernel_*() functions leave the relevant MSR bits enabled
    until we exit the kernel sometime later. Create disable versions
    that wrap the kernel use of FP, Altivec VSX or SPE.

    While we don't want to disable it normally for performance reasons
    (MSR writes are slow), it will be used for a debug boot option that
    does this and catches bad uses in other areas of the kernel.

    Signed-off-by: Anton Blanchard
    Signed-off-by: Michael Ellerman

    Anton Blanchard
     

22 Apr, 2015

1 commit

  • fe5cbc6e0   md/raid6 algorithms: delta syndrome functions ... Browse Code »

    v3: s-o-b comment, explanation of performance and descision for
    the start/stop implementation

    Implementing rmw functionality for RAID6 requires optimized syndrome
    calculation. Up to now we can only generate a complete syndrome. The
    target P/Q pages are always overwritten. With this patch we provide
    a framework for inplace P/Q modification. In the first place simply
    fill those functions with NULL values.

    xor_syndrome() has two additional parameters: start & stop. These
    will indicate the first and last page that are changing during a
    rmw run. That makes it possible to avoid several unneccessary loops
    and speed up calculation. The caller needs to implement the following
    logic to make the functions work.

    1) xor_syndrome(disks, start, stop, ...): "Remove" all data of source
    blocks inside P/Q between (and including) start and end.

    2) modify any block with start
    Signed-off-by: NeilBrown

    Markus Stockhausen
     

13 Dec, 2012

1 commit

29 Mar, 2012

2 commits

11 Aug, 2010

1 commit