linux-stable.git/arch/s390/lib, branch v4.2

s390: remove "64" suffix from mem64.S and swsusp_asm64.S

2015-03-25T10:49:51+00:00

Rename two more files which I forgot. Also remove the "asm" from the
swsusp_asm64.S file, since the ".S" suffix already makes it obvious
that this file contains assembler code.

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

s390: remove 31 bit support

2015-03-25T10:49:33+00:00

Remove the 31 bit support in order to reduce maintenance cost and
effectively remove dead code. Since a couple of years there is no
distribution left that comes with a 31 bit kernel.

The 31 bit kernel also has been broken since more than a year before
anybody noticed. In addition I added a removal warning to the kernel
shown at ipl for 5 minutes: a960062e5826 ("s390: add 31 bit warning
message") which let everybody know about the plan to remove 31 bit
code. We didn't get any response.

Given that the last 31 bit only machine was introduced in 1999 let's
remove the code.
Anybody with 31 bit user space code can still use the compat mode.

Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

s390/spinlock: add compare-and-delay to lock wait loops

2015-01-23T14:17:04+00:00

Add the compare-and-delay instruction to the spin-lock and rw-lock
retry loops. A CPU executing the compare-and-delay instruction stops
until the lock value has changed. This is done to make the locking
code for contended locks to behave better in regard to the multi-
hreading facility. A thread of a core executing a compare-and-delay
will allow the other threads of a core to get a larger share of the
core resources.

Signed-off-by: Martin Schwidefsky

s390/uprobes: fix kprobes dependency

2014-10-17T12:45:51+00:00

If kprobes is disabled uprobes will not compile.
Fix this by including the correct header files.

Signed-off-by: Jan Willeke 
Signed-off-by: Martin Schwidefsky

s390/idle: consolidate idle functions and definitions

2014-10-09T07:14:03+00:00

Move the C functions and definitions related to the idle state handling
to arch/s390/include/asm/idle.h and arch/s390/kernel/idle.c. The function
s390_get_idle_time is renamed to arch_cpu_idle_time and vtime_stop_cpu to
enabled_wait.

Signed-off-by: Martin Schwidefsky

s390/uprobes: common library for kprobes and uprobes

2014-09-25T08:52:14+00:00

This patch moves common functions from kprobes.c to probes.c.
Thus its possible for uprobes to use them without enabling kprobes.

Signed-off-by: Jan Willeke 
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

s390/rwlock: use the interlocked-access facility 1 instructions

2014-09-25T08:52:13+00:00

Make use of the load-and-add, load-and-or and load-and-and instructions
to atomically update the read-write lock without a compare-and-swap loop.

Signed-off-by: Martin Schwidefsky

s390/rwlock: improve writer fairness

2014-09-25T08:52:12+00:00

Set the write-lock bit in the out-of-line rwlock code to indicate that
a writer is waiting. Additional readers will no be able to get the lock
until at least one writer got the lock. Additional writers have to wait
for the first writer to release the lock again.

Signed-off-by: Martin Schwidefsky

s390/rwlock: remove interrupt-enabling rwlock variant.

2014-09-25T08:52:10+00:00

Signed-off-by: Martin Schwidefsky

s390/rwlock: use directed yield for write-locked rwlocks

2014-09-25T08:52:05+00:00

Add an owner field to the arch_rwlock_t to be able to pass the timeslice
of a virtual CPU with diagnose 0x9c to the lock owner in case the rwlock
is write-locked. The undirected yield in case the rwlock is acquired
writable but the lock is read-locked is removed.

Signed-off-by: Martin Schwidefsky