0day-ci / linux

Calculate byte core set for data sample:
Sort bucket's numbers in decreasing order
Count how many numbers use 90% of sample
If core set are low (<=25%), data are easily compressible
If core set high (>=80%), data are not compressible

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Calculate byte set size for data sample:
Calculate how many unique bytes has been in sample
By count all bytes in bucket with count > 0
If byte set low (~25%), data are easily compressible

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Get small sample from input data and calculate
byte type count for that sample into bucket.
Bucket will store info about which bytes
and how many has been detected in sample

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

In support of a soon to be published MFD driver using serdev to talk to
a supervisory processor that uses the CCITT-FALSE CRC16 variant in it's
protocol, this patch was tested successfully on an i.MX6 ARM platform.

Link: http://lkml.kernel.org/r/20170413142932.27287-1-andrew.smirnov@gmail.com
Signed-off-by: Andrey Vostrikov <andrey.vostrikov@cogentembedded.com>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Tested-by: Chris Healy <cphealy@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Early in boot Linux patches memset and memcpy to branch to platform
optimized versions of these routines.  The NG4 (Niagra 4) versions are
currently used on all platforms starting from T4.  Recently, there were M7
optimized routines added into UEK4 but not into mainline yet.  So, even
with M7 optimized routines NG4 are still going to be used on T4, T5, M5,
and M6 processors.

While investigating how to improve initialization time of dentry_hashtable
which is 8G long on M6 ldom with 7T of main memory, I noticed that
memset() does not reset all the memory in this array, after studying the
code, I realized that NG4memset() branches use %icc register instead of
%xcc to check compare, so if value of length is over 32-bit long, which is
true for 8G array, these routines fail to work properly.

The fix is to replace all %icc with %xcc in these routines.  (Alternative
is to use %ncc, but this is misleading, as the code already has sparcv9
only instructions, and cannot be compiled on 32-bit).

This is important to fix this bug, because even older T4-4 can have 2T of
memory, and there are large memory proportional data structures in kernel
which can be larger than 4G in size.  The failing of memset() is silent
and corruption is hard to detect.

Link: http://lkml.kernel.org/r/1488432825-92126-2-git-send-email-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Cc: David Miller <davem@davemloft.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

This resolves a merge issue and gets the vmbox drm driver into this
branch to be able to start taking fixes for it...

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>