linux-stable.git/arch/parisc/lib, branch v4.8

parisc: Change structure intialisation to C99 style in iomap.c

2016-08-02T14:44:34+00:00

Replace the in order struct initialisation style with explicit field
style.

Signed-off-by: Amitoj Kaur Chawla 
Signed-off-by: Helge Deller

parisc: Add native high-resolution sched_clock() implementation

2016-05-22T19:39:25+00:00

Add a native implementation for the sched_clock() function which utilizes the
processor-internal cycle counter (Control Register 16) as high-resolution time
source.

With this patch we now get much more fine-grained resolutions in various
in-kernel time measurements (e.g. when viewing the function tracing logs), and
probably a more accurate scheduling on SMP systems.

There are a few specific implementation details in this patch:

1. On a 32bit kernel we emulate the higher 32bits of the required 64-bit
resolution of sched_clock() by increasing a per-cpu counter at every
wrap-around of the 32bit cycle counter.

2. In a SMP system, the cycle counters of the various CPUs are not syncronized
(similiar to the TSC in a x86_64 system). To cope with this we define
HAVE_UNSTABLE_SCHED_CLOCK and let the upper layers do the adjustment work.

3. Since we need HAVE_UNSTABLE_SCHED_CLOCK, we need to provide a cmpxchg64()
function even on a 32-bit kernel.

4. A 64-bit SMP kernel which is started on a UP system will mark the
sched_clock() implementation as "stable", which means that we don't expect any
jumps in the returned counter. This is true because we then run only on one
CPU.

Signed-off-by: Helge Deller

parisc: Unbreak handling exceptions from kernel modules

2016-04-08T20:14:14+00:00

Handling exceptions from modules never worked on parisc.
It was just masked by the fact that exceptions from modules
don't happen during normal use.

When a module triggers an exception in get_user() we need to load the
main kernel dp value before accessing the exception_data structure, and
afterwards restore the original dp value of the module on exit.

Noticed-by: Mikulas Patocka 
Signed-off-by: Helge Deller 
Cc: stable@vger.kernel.org

parisc: percpu: update comments referring to __get_cpu_var

2014-12-13T20:42:53+00:00

__get_cpu_var was removed. Update comments to refer to
this_cpu_ptr() instead.

Signed-off-by: Christoph Lameter 
Cc: "James E.J. Bottomley" 
Cc: Tejun Heo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

parisc: Replace __get_cpu_var uses for address calculation

2014-04-03T18:50:33+00:00

Convert to the use of this_cpu_ptr().

Cc: "James E.J. Bottomley" 
Cc: Helge Deller 
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Christoph Lameter 
Signed-off-by: Helge Deller

parisc: size_t is unsigned, so comparison size < 0 doesn't make sense.

2013-11-19T23:09:42+00:00

Signed-off-by: Helge Deller 
CC: Mikulas Patocka

parisc: do not inline pa_memcpy() internal functions

2013-11-19T22:36:16+00:00

gcc (4.8.x) creates wrong code when the pa_memcpy() functions are
inlined.  Especially in 32bit builds it calculates wrong return values
if we encounter a fault during execution of the memcpy.

Signed-off-by: Helge Deller

parisc: make udelay() SMP-safe

2013-11-07T21:28:26+00:00

Each CPU has it's own Control Register 16 (CR16) which is used as time source
for the udelay() function. But since the CR16 registers across different CPUs
are not synced, we need to recalculate the loop count if we get switched away
to ensure that we really delay as much time as requested.

Signed-off-by: Helge Deller

parisc: provide macro to create exception table entries

2013-11-07T21:25:33+00:00

Provide a macro ASM_EXCEPTIONTABLE_ENTRY() to create exception table
entries and convert all open-coded places to use that macro.

This patch is a first step toward creating a exception table which only
holds 32bit pointers even on a 64bit kernel. That way in my own kernel
I was able to reduce the in-kernel exception table from 44kB to 22kB.

Signed-off-by: Helge Deller

parisc: let probe_kernel_read() capture access to page zero

2013-10-13T15:46:31+00:00

Signed-off-by: Helge Deller