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s390/spinlock: use the cpu number +1 as spinlock value 

The queued spinlock code will come out simpler if the encoding of
the CPU that holds the spinlock is (cpu+1) instead of (~cpu).

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Martin Schwidefsky 2016-12-04 14:36:04 +01:00
parent 1887aa07b6
commit 8153380379
2 changed files with 17 additions and 17 deletions
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2
arch/s390/include/asm/spinlock.h
View File

@ -48,7 +48,7 @@ static inline void arch_spin_relax(arch_spinlock_t *lock)
static inline u32 arch_spin_lockval(int cpu)
{
return ~cpu;
return cpu + 1;
}
static inline int arch_spin_value_unlocked(arch_spinlock_t lock)

32
arch/s390/lib/spinlock.c
View File

@ -67,8 +67,8 @@ void arch_spin_lock_wait(arch_spinlock_t *lp)
/* Pass the virtual CPU to the lock holder if it is not running */
owner = arch_load_niai4(&lp->lock);
if (owner && arch_vcpu_is_preempted(~owner))
smp_yield_cpu(~owner);
if (owner && arch_vcpu_is_preempted(owner - 1))
smp_yield_cpu(owner - 1);
count = spin_retry;
while (1) {
@ -87,8 +87,8 @@ void arch_spin_lock_wait(arch_spinlock_t *lp)
* yield the CPU unconditionally. For LPAR rely on the
* sense running status.
*/
if (!MACHINE_IS_LPAR || arch_vcpu_is_preempted(~owner))
smp_yield_cpu(~owner);
if (!MACHINE_IS_LPAR || arch_vcpu_is_preempted(owner - 1))
smp_yield_cpu(owner - 1);
}
}
EXPORT_SYMBOL(arch_spin_lock_wait);
@ -102,8 +102,8 @@ void arch_spin_lock_wait_flags(arch_spinlock_t *lp, unsigned long flags)
/* Pass the virtual CPU to the lock holder if it is not running */
owner = arch_load_niai4(&lp->lock);
if (owner && arch_vcpu_is_preempted(~owner))
smp_yield_cpu(~owner);
if (owner && arch_vcpu_is_preempted(owner - 1))
smp_yield_cpu(owner - 1);
count = spin_retry;
while (1) {
@ -124,8 +124,8 @@ void arch_spin_lock_wait_flags(arch_spinlock_t *lp, unsigned long flags)
* yield the CPU unconditionally. For LPAR rely on the
* sense running status.
*/
if (!MACHINE_IS_LPAR || arch_vcpu_is_preempted(~owner))
smp_yield_cpu(~owner);
if (!MACHINE_IS_LPAR || arch_vcpu_is_preempted(owner - 1))
smp_yield_cpu(owner - 1);
}
}
EXPORT_SYMBOL(arch_spin_lock_wait_flags);
@ -158,8 +158,8 @@ void _raw_read_lock_wait(arch_rwlock_t *rw)
owner = 0;
while (1) {
if (count-- <= 0) {
if (owner && arch_vcpu_is_preempted(~owner))
smp_yield_cpu(~owner);
if (owner && arch_vcpu_is_preempted(owner - 1))
smp_yield_cpu(owner - 1);
count = spin_retry;
}
old = ACCESS_ONCE(rw->lock);
@ -198,8 +198,8 @@ void _raw_write_lock_wait(arch_rwlock_t *rw, int prev)
owner = 0;
while (1) {
if (count-- <= 0) {
if (owner && arch_vcpu_is_preempted(~owner))
smp_yield_cpu(~owner);
if (owner && arch_vcpu_is_preempted(owner - 1))
smp_yield_cpu(owner - 1);
count = spin_retry;
}
old = ACCESS_ONCE(rw->lock);
@ -226,8 +226,8 @@ void _raw_write_lock_wait(arch_rwlock_t *rw)
owner = 0;
while (1) {
if (count-- <= 0) {
if (owner && arch_vcpu_is_preempted(~owner))
smp_yield_cpu(~owner);
if (owner && arch_vcpu_is_preempted(owner - 1))
smp_yield_cpu(owner - 1);
count = spin_retry;
}
old = ACCESS_ONCE(rw->lock);
@ -265,8 +265,8 @@ void arch_lock_relax(int cpu)
{
if (!cpu)
return;
if (MACHINE_IS_LPAR && !arch_vcpu_is_preempted(~cpu))
if (MACHINE_IS_LPAR && !arch_vcpu_is_preempted(cpu - 1))
return;
smp_yield_cpu(~cpu);
smp_yield_cpu(cpu - 1);
}
EXPORT_SYMBOL(arch_lock_relax);