<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/lib/lz4, branch v5.4.69</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.4.69</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.4.69'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2019-09-20T16:06:26Z</updated>
<entry>
<title>lz4: do not export static symbol</title>
<updated>2019-09-20T16:06:26Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2019-09-20T16:06:26Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b08918fb3f27d1843152986e6bc79ec723dba8cc'/>
<id>urn:sha1:b08918fb3f27d1843152986e6bc79ec723dba8cc</id>
<content type='text'>
Kbuild now complains (rightly) about it.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>treewide: Add SPDX license identifier - Makefile/Kconfig</title>
<updated>2019-05-21T08:50:46Z</updated>
<author>
<name>Thomas Gleixner</name>
<email>tglx@linutronix.de</email>
</author>
<published>2019-05-19T12:07:45Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ec8f24b7faaf3d4799a7c3f4c1b87f6b02778ad1'/>
<id>urn:sha1:ec8f24b7faaf3d4799a7c3f4c1b87f6b02778ad1</id>
<content type='text'>
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>lib/lz4: update LZ4 decompressor module</title>
<updated>2018-10-31T15:54:14Z</updated>
<author>
<name>Gao Xiang</name>
<email>gaoxiang25@huawei.com</email>
</author>
<published>2018-10-30T22:07:28Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2209fda323e2fd2a2d0885595fd5097717f8d2aa'/>
<id>urn:sha1:2209fda323e2fd2a2d0885595fd5097717f8d2aa</id>
<content type='text'>
Update the LZ4 compression module based on LZ4 v1.8.3 in order for the
erofs file system to use the newest LZ4_decompress_safe_partial() which
can now decode exactly the nb of bytes requested [1] to take place of the
open hacked code in the erofs file system itself.

Currently, apart from the erofs file system, no other users use
LZ4_decompress_safe_partial, so no worry about the interface.

In addition, LZ4 v1.8.x boosts up decompression speed compared to the
current code which is based on LZ4 v1.7.3, mainly due to shortcut
optimization for the specific common LZ4-sequences [2].

lzbench testdata (tested in kirin710, 8 cores, 4 big cores
at 2189Mhz, 2GB DDR RAM at 1622Mhz, with enwik8 testdata [3]):

Compressor name         Compress. Decompress. Compr. size  Ratio Filename
memcpy                   5004 MB/s  4924 MB/s   100000000 100.00 enwik8
lz4hc 1.7.3 -9             12 MB/s   653 MB/s    42203253  42.20 enwik8
lz4hc 1.8.0 -9             12 MB/s   908 MB/s    42203096  42.20 enwik8
lz4hc 1.8.3 -9             11 MB/s   965 MB/s    42203094  42.20 enwik8

[1] https://github.com/lz4/lz4/issues/566
    https://github.com/lz4/lz4/commit/08d347b5b217b011ff7487130b79480d8cfdaeb8

[2] v1.8.1 perf: slightly faster compression and decompression speed
    https://github.com/lz4/lz4/commit/a31b7058cb97e4393da55e78a77a1c6f0c9ae038
    v1.8.2 perf: slightly faster HC compression and decompression speed
    https://github.com/lz4/lz4/commit/45f8603aae389d34c689d3ff7427b314071ccd2c
    https://github.com/lz4/lz4/commit/1a191b3f8d26b50a7c1d41590b529ec308d768cd

[3] http://mattmahoney.net/dc/textdata.html
    http://mattmahoney.net/dc/enwik8.zip

Link: http://lkml.kernel.org/r/1537181207-21932-1-git-send-email-gaoxiang25@huawei.com
Signed-off-by: Gao Xiang &lt;gaoxiang25@huawei.com&gt;
Tested-by: Guo Xuenan &lt;guoxuenan@huawei.com&gt;
Cc: Colin Ian King &lt;colin.king@canonical.com&gt;
Cc: Yann Collet &lt;yann.collet.73@gmail.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Fang Wei &lt;fangwei1@huawei.com&gt;
Cc: Chao Yu &lt;yuchao0@huawei.com&gt;
Cc: Miao Xie &lt;miaoxie@huawei.com&gt;
Cc: Sven Schmidt &lt;4sschmid@informatik.uni-hamburg.de&gt;
Cc: Kyungsik Lee &lt;kyungsik.lee@lge.com&gt;
Cc: &lt;weidu.du@huawei.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>lib/lz4: make arrays static const, reduces object code size</title>
<updated>2017-10-04T00:54:25Z</updated>
<author>
<name>Colin Ian King</name>
<email>colin.king@canonical.com</email>
</author>
<published>2017-10-03T23:16:01Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=8cb5d7482810b7eb1bb05bf4f71bc93ce35e5896'/>
<id>urn:sha1:8cb5d7482810b7eb1bb05bf4f71bc93ce35e5896</id>
<content type='text'>
Don't populate the read-only arrays dec32table and dec64table on the
stack, instead make them both static const.  Makes the object code
smaller by over 10K bytes:

  Before:
     text	   data	    bss	    dec	    hex	filename
    31500	      0	      0	  31500	   7b0c	lib/lz4/lz4_decompress.o

  After:
     text	   data	    bss	    dec	    hex	filename
    20237	    176	      0	  20413	   4fbd	lib/lz4/lz4_decompress.o

(gcc version 7.2.0 x86_64)

Link: http://lkml.kernel.org/r/20170921221939.20820-1-colin.king@canonical.com
Signed-off-by: Colin Ian King &lt;colin.king@canonical.com&gt;
Cc: Christophe JAILLET &lt;christophe.jaillet@wanadoo.fr&gt;
Cc: Sven Schmidt &lt;4sschmid@informatik.uni-hamburg.de&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Joe Perches &lt;joe@perches.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>lib/lz4: remove back-compat wrappers</title>
<updated>2017-02-25T01:46:57Z</updated>
<author>
<name>Sven Schmidt</name>
<email>4sschmid@informatik.uni-hamburg.de</email>
</author>
<published>2017-02-24T23:01:25Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=69c78423b8f439b077929410bdf8f88e7031b891'/>
<id>urn:sha1:69c78423b8f439b077929410bdf8f88e7031b891</id>
<content type='text'>
Remove the functions introduced as wrappers for providing backwards
compatibility to the prior LZ4 version.  They're not needed anymore
since there's no callers left.

Link: http://lkml.kernel.org/r/1486321748-19085-6-git-send-email-4sschmid@informatik.uni-hamburg.de
Signed-off-by: Sven Schmidt &lt;4sschmid@informatik.uni-hamburg.de&gt;
Cc: Bongkyu Kim &lt;bongkyu.kim@lge.com&gt;
Cc: Rui Salvaterra &lt;rsalvaterra@gmail.com&gt;
Cc: Sergey Senozhatsky &lt;sergey.senozhatsky@gmail.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Anton Vorontsov &lt;anton@enomsg.org&gt;
Cc: Colin Cross &lt;ccross@android.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>lib: update LZ4 compressor module</title>
<updated>2017-02-25T01:46:57Z</updated>
<author>
<name>Sven Schmidt</name>
<email>4sschmid@informatik.uni-hamburg.de</email>
</author>
<published>2017-02-24T23:01:12Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=4e1a33b105ddf201f66dcc44490c6086a25eca0b'/>
<id>urn:sha1:4e1a33b105ddf201f66dcc44490c6086a25eca0b</id>
<content type='text'>
Patch series "Update LZ4 compressor module", v7.

This patchset updates the LZ4 compression module to a version based on
LZ4 v1.7.3 allowing to use the fast compression algorithm aka LZ4 fast
which provides an "acceleration" parameter as a tradeoff between high
compression ratio and high compression speed.

We want to use LZ4 fast in order to support compression in lustre and
(mostly, based on that) investigate data reduction techniques in behalf
of storage systems.

Also, it will be useful for other users of LZ4 compression, as with LZ4
fast it is possible to enable applications to use fast and/or high
compression depending on the usecase.  For instance, ZRAM is offering a
LZ4 backend and could benefit from an updated LZ4 in the kernel.

LZ4 homepage: http://www.lz4.org/
LZ4 source repository: https://github.com/lz4/lz4 Source version: 1.7.3

Benchmark (taken from [1], Core i5-4300U @1.9GHz):
----------------|--------------|----------------|----------
Compressor      | Compression  | Decompression  | Ratio
----------------|--------------|----------------|----------
memcpy          |  4200 MB/s   |  4200 MB/s     | 1.000
LZ4 fast 50     |  1080 MB/s   |  2650 MB/s     | 1.375
LZ4 fast 17     |   680 MB/s   |  2220 MB/s     | 1.607
LZ4 fast 5      |   475 MB/s   |  1920 MB/s     | 1.886
LZ4 default     |   385 MB/s   |  1850 MB/s     | 2.101

[1] http://fastcompression.blogspot.de/2015/04/sampling-or-faster-lz4.html

[PATCH 1/5] lib: Update LZ4 compressor module
[PATCH 2/5] lib/decompress_unlz4: Change module to work with new LZ4 module version
[PATCH 3/5] crypto: Change LZ4 modules to work with new LZ4 module version
[PATCH 4/5] fs/pstore: fs/squashfs: Change usage of LZ4 to work with new LZ4 version
[PATCH 5/5] lib/lz4: Remove back-compat wrappers

This patch (of 5):

Update the LZ4 kernel module to LZ4 v1.7.3 by Yann Collet.  The kernel
module is inspired by the previous work by Chanho Min.  The updated LZ4
module will not break existing code since the patchset contains
appropriate changes.

API changes:

New method LZ4_compress_fast which differs from the variant available in
kernel by the new acceleration parameter, allowing to trade compression
ratio for more compression speed and vice versa.

LZ4_decompress_fast is the respective decompression method, featuring a
very fast decoder (multiple GB/s per core), able to reach RAM speed in
multi-core systems.  The decompressor allows to decompress data
compressed with LZ4 fast as well as the LZ4 HC (high compression)
algorithm.

Also the useful functions LZ4_decompress_safe_partial and
LZ4_compress_destsize were added.  The latter reverses the logic by
trying to compress as much data as possible from source to dest while
the former aims to decompress partial blocks of data.

A bunch of streaming functions were also added which allow
compressig/decompressing data in multiple steps (so called "streaming
mode").

The methods lz4_compress and lz4_decompress_unknownoutputsize are now
known as LZ4_compress_default respectivley LZ4_decompress_safe.  The old
methods will be removed since there's no callers left in the code.

[arnd@arndb.de: fix KERNEL_LZ4 support]
  Link: http://lkml.kernel.org/r/20170208211946.2839649-1-arnd@arndb.de
[akpm@linux-foundation.org: simplify]
[akpm@linux-foundation.org: fix the simplification]
[4sschmid@informatik.uni-hamburg.de: fix performance regressions]
  Link: http://lkml.kernel.org/r/1486898178-17125-2-git-send-email-4sschmid@informatik.uni-hamburg.de
[4sschmid@informatik.uni-hamburg.de: v8]
  Link: http://lkml.kernel.org/r/1487182598-15351-2-git-send-email-4sschmid@informatik.uni-hamburg.de
Link: http://lkml.kernel.org/r/1486321748-19085-2-git-send-email-4sschmid@informatik.uni-hamburg.de
Signed-off-by: Sven Schmidt &lt;4sschmid@informatik.uni-hamburg.de&gt;
Signed-off-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Bongkyu Kim &lt;bongkyu.kim@lge.com&gt;
Cc: Rui Salvaterra &lt;rsalvaterra@gmail.com&gt;
Cc: Sergey Senozhatsky &lt;sergey.senozhatsky@gmail.com&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Anton Vorontsov &lt;anton@enomsg.org&gt;
Cc: Colin Cross &lt;ccross@android.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>lib: lz4: cleanup unaligned access efficiency detection</title>
<updated>2016-04-13T16:22:49Z</updated>
<author>
<name>Rui Salvaterra</name>
<email>rsalvaterra@gmail.com</email>
</author>
<published>2016-04-09T21:05:35Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=dea5c24a14047b7d6b6b269434a85ffd05f1d2cb'/>
<id>urn:sha1:dea5c24a14047b7d6b6b269434a85ffd05f1d2cb</id>
<content type='text'>
These identifiers are bogus. The interested architectures should define
HAVE_EFFICIENT_UNALIGNED_ACCESS whenever relevant to do so. If this
isn't true for some arch, it should be fixed in the arch definition.

Signed-off-by: Rui Salvaterra &lt;rsalvaterra@gmail.com&gt;
Reviewed-by: Sergey Senozhatsky &lt;sergey.senozhatsky@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>lib: lz4: fixed zram with lz4 on big endian machines</title>
<updated>2016-04-13T16:22:49Z</updated>
<author>
<name>Rui Salvaterra</name>
<email>rsalvaterra@gmail.com</email>
</author>
<published>2016-04-09T21:05:34Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=3e26a691fe3fe1e02a76e5bab0c143ace4b137b4'/>
<id>urn:sha1:3e26a691fe3fe1e02a76e5bab0c143ace4b137b4</id>
<content type='text'>
Based on Sergey's test patch [1], this fixes zram with lz4 compression
on big endian cpus.

Note that the 64-bit preprocessor test is not a cleanup, it's part of
the fix, since those identifiers are bogus (for example, __ppc64__
isn't defined anywhere else in the kernel, which means we'd fall into
the 32-bit definitions on ppc64).

Tested on ppc64 with no regression on x86_64.

[1] http://marc.info/?l=linux-kernel&amp;m=145994470805853&amp;w=4

Cc: stable@vger.kernel.org
Suggested-by: Sergey Senozhatsky &lt;sergey.senozhatsky@gmail.com&gt;
Signed-off-by: Rui Salvaterra &lt;rsalvaterra@gmail.com&gt;
Reviewed-by: Sergey Senozhatsky &lt;sergey.senozhatsky@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>lz4: fix system halt at boot kernel on x86_64</title>
<updated>2015-05-24T18:56:29Z</updated>
<author>
<name>Krzysztof Kolasa</name>
<email>kkolasa@winsoft.pl</email>
</author>
<published>2015-05-04T03:58:59Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=99b7e93c95c78952724a9783de6c78def8fbfc3f'/>
<id>urn:sha1:99b7e93c95c78952724a9783de6c78def8fbfc3f</id>
<content type='text'>
Sometimes, on x86_64, decompression fails with the following
error:

Decompressing Linux...

Decoding failed

 -- System halted

This condition is not needed for a 64bit kernel(from commit d5e7caf):

if( ... ||
    (op + COPYLENGTH) &gt; oend)
    goto _output_error

macro LZ4_SECURE_COPY() tests op and does not copy any data
when op exceeds the value.

added by analogy to lz4_uncompress_unknownoutputsize(...)

Signed-off-by: Krzysztof Kolasa &lt;kkolasa@winsoft.pl&gt;
Tested-by: Alexander Kuleshov &lt;kuleshovmail@gmail.com&gt;
Tested-by: Caleb Jorden &lt;cjorden@gmail.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>lib/lz4: Pull out constant tables</title>
<updated>2015-03-25T14:04:57Z</updated>
<author>
<name>Rasmus Villemoes</name>
<email>linux@rasmusvillemoes.dk</email>
</author>
<published>2015-02-10T10:12:21Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=bea2b592fd18eb8ffa3fc4ad380610632d03a38f'/>
<id>urn:sha1:bea2b592fd18eb8ffa3fc4ad380610632d03a38f</id>
<content type='text'>
There's no reason to allocate the dec{32,64}table on the stack; it
just wastes a bunch of instructions setting them up and, of course,
also consumes quite a bit of stack. Using size_t for such small
integers is a little excessive.

$ scripts/bloat-o-meter /tmp/built-in.o lib/built-in.o
add/remove: 2/2 grow/shrink: 2/0 up/down: 1304/-1548 (-244)
function                                     old     new   delta
lz4_decompress_unknownoutputsize              55     718    +663
lz4_decompress                                55     632    +577
dec64table                                     -      32     +32
dec32table                                     -      32     +32
lz4_uncompress                               747       -    -747
lz4_uncompress_unknownoutputsize             801       -    -801

The now inlined lz4_uncompress functions used to have a stack
footprint of 176 bytes (according to -fstack-usage); their inlinees
have increased their stack use from 32 bytes to 48 and 80 bytes,
respectively.

Signed-off-by: Rasmus Villemoes &lt;linux@rasmusvillemoes.dk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
</feed>
