linux-toradex.git/arch/s390/lib/spinlock.c, branch v3.9.2

s390/comments: unify copyright messages and remove file names

2012-07-20T09:15:04+00:00

Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.

Signed-off-by: Heiko Carstens

[S390] rework smp code

2012-03-11T15:59:28+00:00

Define struct pcpu and merge some of the NR_CPUS arrays into it, including
__cpu_logical_map, current_set and smp_cpu_state. Split smp related
functions to those operating on physical cpus and the functions operating
on a logical cpu number. Make the functions for physical cpus use a
pointer to a struct pcpu. This hides the knowledge about cpu addresses in
smp.c, entry[64].S and swsusp_asm64.S, thus remove the sigp.h header.

The PSW restart mechanism is used to start secondary cpus, calling a
function on an online cpu, calling a function on the ipl cpu, and for
the nmi signal. Replace the different assembler functions with a
single function restart_int_handler. The new entry point calls a function
whose pointer is stored in the lowcore of the target cpu and it can wait
for the source cpu to stop. This covers all existing use cases.

Overall the code is now simpler and there are ~380 lines less code.

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

[S390] spinlock: check virtual cpu running status

2010-02-26T21:37:31+00:00

This patch introduces a new function that checks the running status
of a cpu in a hypervisor. This status is not virtualized, so the check
is only correct if running in an LPAR. On acquiring a spinlock, if the
cpu holding the lock is scheduled by the hypervisor, we do a busy wait
on the lock. If it is not scheduled, we yield over to that cpu.

Signed-off-by: Gerald Schaefer 
Signed-off-by: Martin Schwidefsky

[S390] Move __cpu_logical_map to smp.c

2010-01-13T19:44:45+00:00

Finally move it to the place where it belongs to and make get rid of
it for !CONFIG_SMP.

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

locking: Convert raw_rwlock functions to arch_rwlock

2009-12-14T22:55:32+00:00

Name space cleanup for rwlock functions. No functional change.

Signed-off-by: Thomas Gleixner 
Acked-by: Peter Zijlstra 
Acked-by: David S. Miller 
Acked-by: Ingo Molnar 
Cc: linux-arch@vger.kernel.org

locking: Convert raw_rwlock to arch_rwlock

2009-12-14T22:55:32+00:00

Not strictly necessary for -rt as -rt does not have non sleeping
rwlocks, but it's odd to not have a consistent naming convention.

No functional change.

Signed-off-by: Thomas Gleixner 
Acked-by: Peter Zijlstra 
Acked-by: David S. Miller 
Acked-by: Ingo Molnar 
Cc: linux-arch@vger.kernel.org

locking: Convert __raw_spin* functions to arch_spin*

2009-12-14T22:55:32+00:00

Name space cleanup. No functional change.

Signed-off-by: Thomas Gleixner 
Acked-by: Peter Zijlstra 
Acked-by: David S. Miller 
Acked-by: Ingo Molnar 
Cc: linux-arch@vger.kernel.org

locking: Convert raw_spinlock to arch_spinlock

2009-12-14T22:55:32+00:00

The raw_spin* namespace was taken by lockdep for the architecture
specific implementations. raw_spin_* would be the ideal name space for
the spinlocks which are not converted to sleeping locks in preempt-rt.

Linus suggested to convert the raw_ to arch_ locks and cleanup the
name space instead of using an artifical name like core_spin,
atomic_spin or whatever

No functional change.

Signed-off-by: Thomas Gleixner 
Acked-by: Peter Zijlstra 
Acked-by: David S. Miller 
Acked-by: Ingo Molnar 
Cc: linux-arch@vger.kernel.org

[S390] implement interrupt-enabling rwlocks

2009-06-12T08:27:29+00:00

arch backend for f5f7eac41db827a47b2163330eecd7bb55ae9f12
"Allow rwlocks to re-enable interrupts".

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

[S390] do local_irq_restore while spinning in spin_lock_irqsave.

2008-01-26T13:11:31+00:00

In s390's spin_lock_irqsave, interrupts remain disabled while
spinning. In other architectures like x86 and powerpc, interrupts are
re-enabled while spinning if IRQ is not masked before spin_lock_irqsave
is called.

The following patch re-enables interrupts through local_irq_restore
while spinning for a lock acquisition.
This can improve system response.

[heiko.carstens@de.ibm.com: removed saving of pc]

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