<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/lib/raid6/.gitignore, branch master</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>.gitignore: add SPDX License Identifier</title>
<updated>2020-03-25T10:50:48+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2020-03-03T13:35:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d198b34f3855eee2571dda03eea75a09c7c31480'/>
<id>d198b34f3855eee2571dda03eea75a09c7c31480</id>
<content type='text'>
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
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<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/raid6/altivec: Add vpermxor implementation for raid6 Q syndrome</title>
<updated>2018-03-20T05:47:25+00:00</updated>
<author>
<name>Matt Brown</name>
<email>matthew.brown.dev@gmail.com</email>
</author>
<published>2017-08-04T03:42:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=751ba79cc552c146595cd439b21c4ff8998c3b69'/>
<id>751ba79cc552c146595cd439b21c4ff8998c3b69</id>
<content type='text'>
This patch uses the vpermxor instruction to optimise the raid6 Q
syndrome. This instruction was made available with POWER8, ISA version
2.07. It allows for both vperm and vxor instructions to be done in a
single instruction. This has been tested for correctness on a ppc64le
vm with a basic RAID6 setup containing 5 drives.

The performance benchmarks are from the raid6test in the
/lib/raid6/test directory. These results are from an IBM Firestone
machine with ppc64le architecture. The benchmark results show a 35%
speed increase over the best existing algorithm for powerpc (altivec).
The raid6test has also been run on a big-endian ppc64 vm to ensure it
also works for big-endian architectures.

Performance benchmarks:
  raid6: altivecx4 gen() 18773 MB/s
  raid6: altivecx8 gen() 19438 MB/s

  raid6: vpermxor4 gen() 25112 MB/s
  raid6: vpermxor8 gen() 26279 MB/s

Signed-off-by: Matt Brown &lt;matthew.brown.dev@gmail.com&gt;
Reviewed-by: Daniel Axtens &lt;dja@axtens.net&gt;
[mpe: Add VPERMXOR macro so we can build with old binutils]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch uses the vpermxor instruction to optimise the raid6 Q
syndrome. This instruction was made available with POWER8, ISA version
2.07. It allows for both vperm and vxor instructions to be done in a
single instruction. This has been tested for correctness on a ppc64le
vm with a basic RAID6 setup containing 5 drives.

The performance benchmarks are from the raid6test in the
/lib/raid6/test directory. These results are from an IBM Firestone
machine with ppc64le architecture. The benchmark results show a 35%
speed increase over the best existing algorithm for powerpc (altivec).
The raid6test has also been run on a big-endian ppc64 vm to ensure it
also works for big-endian architectures.

Performance benchmarks:
  raid6: altivecx4 gen() 18773 MB/s
  raid6: altivecx8 gen() 19438 MB/s

  raid6: vpermxor4 gen() 25112 MB/s
  raid6: vpermxor8 gen() 26279 MB/s

Signed-off-by: Matt Brown &lt;matthew.brown.dev@gmail.com&gt;
Reviewed-by: Daniel Axtens &lt;dja@axtens.net&gt;
[mpe: Add VPERMXOR macro so we can build with old binutils]
Signed-off-by: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>RAID/s390: add SIMD implementation for raid6 gen/xor</title>
<updated>2016-08-29T09:05:04+00:00</updated>
<author>
<name>Martin Schwidefsky</name>
<email>schwidefsky@de.ibm.com</email>
</author>
<published>2016-08-23T11:30:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=474fd6e80fe529e9adeeb7ea9d4e5d6c4da0b7fe'/>
<id>474fd6e80fe529e9adeeb7ea9d4e5d6c4da0b7fe</id>
<content type='text'>
Using vector registers is slightly faster:

raid6: vx128x8  gen() 19705 MB/s
raid6: vx128x8  xor() 11886 MB/s
raid6: using algorithm vx128x8 gen() 19705 MB/s
raid6: .... xor() 11886 MB/s, rmw enabled

vs the software algorithms:

raid6: int64x1  gen()  3018 MB/s
raid6: int64x1  xor()  1429 MB/s
raid6: int64x2  gen()  4661 MB/s
raid6: int64x2  xor()  3143 MB/s
raid6: int64x4  gen()  5392 MB/s
raid6: int64x4  xor()  3509 MB/s
raid6: int64x8  gen()  4441 MB/s
raid6: int64x8  xor()  3207 MB/s
raid6: using algorithm int64x4 gen() 5392 MB/s
raid6: .... xor() 3509 MB/s, rmw enabled

Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Using vector registers is slightly faster:

raid6: vx128x8  gen() 19705 MB/s
raid6: vx128x8  xor() 11886 MB/s
raid6: using algorithm vx128x8 gen() 19705 MB/s
raid6: .... xor() 11886 MB/s, rmw enabled

vs the software algorithms:

raid6: int64x1  gen()  3018 MB/s
raid6: int64x1  xor()  1429 MB/s
raid6: int64x2  gen()  4661 MB/s
raid6: int64x2  xor()  3143 MB/s
raid6: int64x4  gen()  5392 MB/s
raid6: int64x4  xor()  3509 MB/s
raid6: int64x8  gen()  4441 MB/s
raid6: int64x8  xor()  3207 MB/s
raid6: using algorithm int64x4 gen() 5392 MB/s
raid6: .... xor() 3509 MB/s, rmw enabled

Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/raid6: add ARM-NEON accelerated syndrome calculation</title>
<updated>2013-07-08T21:09:18+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2013-05-16T15:20:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7d11965ddb9b9b1e0a5d13c58345ada1ccbc663b'/>
<id>7d11965ddb9b9b1e0a5d13c58345ada1ccbc663b</id>
<content type='text'>
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 &lt;ard.biesheuvel@linaro.org&gt;
Acked-by: Nicolas Pitre &lt;nico@linaro.org&gt;
Cc: hpa@linux.intel.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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 &lt;ard.biesheuvel@linaro.org&gt;
Acked-by: Nicolas Pitre &lt;nico@linaro.org&gt;
Cc: hpa@linux.intel.com
</pre>
</div>
</content>
</entry>
<entry>
<title>Move .gitignore from drivers/md to lib/raid6</title>
<updated>2010-08-30T07:35:52+00:00</updated>
<author>
<name>NeilBrown</name>
<email>neilb@suse.de</email>
</author>
<published>2010-08-30T07:35:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7c44ece988a3419e51c833cf14be186a22224dd1'/>
<id>7c44ece988a3419e51c833cf14be186a22224dd1</id>
<content type='text'>
Another missing bit of the raid6 -&gt; /lib move.

Reported-by: Andreas Schwab &lt;schwab@linux-m68k.org&gt;
Signed-off-by: NeilBrown &lt;neilb@suse.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Another missing bit of the raid6 -&gt; /lib move.

Reported-by: Andreas Schwab &lt;schwab@linux-m68k.org&gt;
Signed-off-by: NeilBrown &lt;neilb@suse.de&gt;
</pre>
</div>
</content>
</entry>
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