linux-toradex.git/lib/raid6/algos.c, branch v4.0-rc1

x86/raid6: correctly check for assembler capabilities

2015-02-03T21:35:51+00:00

Just like for AVX2 (which simply needs an #if -> #ifdef conversion),
SSSE3 assembler support should be checked for before using it.

Signed-off-by: Jan Beulich 
Cc: Jim Kukunas 
Acked-by: Thomas Gleixner 
Signed-off-by: NeilBrown

lib/raid6: Add log level to printks

2014-10-14T02:08:29+00:00

Signed-off-by: Anton Blanchard 
Signed-off-by: NeilBrown

Merge tag 'md/3.12' of git://neil.brown.name/md

2013-09-10T20:03:41+00:00

Pull md update from Neil Brown:
 "Headline item is multithreading for RAID5 so that more IO/sec can be
  supported on fast (SSD) devices.  Also TILE-Gx SIMD suppor for RAID6
  calculations and an assortment of bug fixes"

* tag 'md/3.12' of git://neil.brown.name/md:
  raid5: only wakeup necessary threads
  md/raid5: flush out all pending requests before proceeding with reshape.
  md/raid5: use seqcount to protect access to shape in make_request.
  raid5: sysfs entry to control worker thread number
  raid5: offload stripe handle to workqueue
  raid5: fix stripe release order
  raid5: make release_stripe lockless
  md: avoid deadlock when dirty buffers during md_stop.
  md: Don't test all of mddev->flags at once.
  md: Fix apparent cut-and-paste error in super_90_validate
  raid6/test: replace echo -e with printf
  RAID: add tilegx SIMD implementation of raid6
  md: fix safe_mode buglet.
  md: don't call md_allow_write in get_bitmap_file.

RAID: add tilegx SIMD implementation of raid6

2013-08-27T06:05:50+00:00

This change adds TILE-Gx SIMD instructions to the software raid
(md), modeling the Altivec implementation. This is only for Syndrome
generation; there is more that could be done to improve recovery,
as in the recent Intel SSE3 recovery implementation.

The code unrolls 8 times; this turns out to be the best on tilegx
hardware among the set 1, 2, 4, 8 or 16.  The code reads one
cache-line of data from each disk, stores P and Q then goes to the
next cache-line.

The test code in sys/linux/lib/raid6/test reports 2008 MB/s data
read rate for syndrome generation using 18 disks (16 data and 2
parity). It was 1512 MB/s before this SIMD optimizations. This is
running on 1 core with all the data in cache.

This is based on the paper The Mathematics of RAID-6.
(http://kernel.org/pub/linux/kernel/people/hpa/raid6.pdf).

Signed-off-by: Ken Steele 
Signed-off-by: Chris Metcalf 
Signed-off-by: NeilBrown

lib/raid6: add ARM-NEON accelerated syndrome calculation

2013-07-08T21:09:18+00:00

Rebased/reworked a patch contributed by Rob Herring that uses
NEON intrinsics to perform the RAID-6 syndrome calculations.
It uses the existing unroll.awk code to generate several
unrolled versions of which the best performing one is selected
at boot time.

Signed-off-by: Ard Biesheuvel 
Acked-by: Nicolas Pitre 
Cc: hpa@linux.intel.com

lib/raid6: Add AVX2 optimized gen_syndrome functions

2012-12-13T08:51:03+00:00

Add AVX2 optimized gen_syndrom functions, which is simply based on
sse2.c written by hpa.

Signed-off-by: Yuanhan Liu 
Reviewed-by: H. Peter Anvin 
Signed-off-by: Jim Kukunas 
Signed-off-by: NeilBrown

lib/raid6: Add AVX2 optimized recovery functions

2012-12-13T05:42:01+00:00

Optimize RAID6 recovery functions to take advantage of
the 256-bit YMM integer instructions introduced in AVX2.

The patch was tested and benchmarked before submission.
However hardware is not yet released so benchmark numbers
cannot be reported.

Acked-by: "H. Peter Anvin" 
Signed-off-by: Jim Kukunas 
Signed-off-by: NeilBrown

lib/raid6: cleanup gen_syndrome function selection

2012-05-22T03:54:24+00:00

Reorders functions in raid6_algos as well as the preference check
to reduce the number of functions tested on initialization.

Also, creates symmetry between choosing the gen_syndrome functions
and choosing the recovery functions.

Signed-off-by: Jim Kukunas 
Signed-off-by: NeilBrown

lib/raid6: Add SSSE3 optimized recovery functions

2012-05-22T03:54:18+00:00

Add SSSE3 optimized recovery functions, as well as a system
for selecting the most appropriate recovery functions to use.

Originally-by: H. Peter Anvin 
Signed-off-by: Jim Kukunas 
Signed-off-by: NeilBrown

lib/raid6: fix test program build

2012-05-22T03:54:16+00:00

 drags in headers which are not visible to userspace,
thus breaking the build for the test program.

Signed-off-by: Jim Kukunas 
Signed-off-by: NeilBrown