powerpc/spinlocks: Refactor SHARED_PROCESSOR

Determining if a processor is in shared processor mode is not a constant
so don't hide it behind a #define.

Signed-off-by: Christopher M. Riedl <cmr@informatik.wtf>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190813031314.1828-2-cmr@informatik.wtf
This commit is contained in:
Christopher M. Riedl 2019-08-12 22:13:12 -05:00 committed by Michael Ellerman
parent d7fb5b18a5
commit d57b78353a
1 changed files with 18 additions and 6 deletions

View File

@ -101,15 +101,27 @@ static inline int arch_spin_trylock(arch_spinlock_t *lock)
#if defined(CONFIG_PPC_SPLPAR)
/* We only yield to the hypervisor if we are in shared processor mode */
#define SHARED_PROCESSOR (lppaca_shared_proc(local_paca->lppaca_ptr))
extern void __spin_yield(arch_spinlock_t *lock);
extern void __rw_yield(arch_rwlock_t *lock);
#else /* SPLPAR */
#define __spin_yield(x) barrier()
#define __rw_yield(x) barrier()
#define SHARED_PROCESSOR 0
#endif
static inline bool is_shared_processor(void)
{
/*
* LPPACA is only available on Pseries so guard anything LPPACA related to
* allow other platforms (which include this common header) to compile.
*/
#ifdef CONFIG_PPC_PSERIES
return (IS_ENABLED(CONFIG_PPC_SPLPAR) &&
lppaca_shared_proc(local_paca->lppaca_ptr));
#else
return false;
#endif
}
static inline void arch_spin_lock(arch_spinlock_t *lock)
{
while (1) {
@ -117,7 +129,7 @@ static inline void arch_spin_lock(arch_spinlock_t *lock)
break;
do {
HMT_low();
if (SHARED_PROCESSOR)
if (is_shared_processor())
__spin_yield(lock);
} while (unlikely(lock->slock != 0));
HMT_medium();
@ -136,7 +148,7 @@ void arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags)
local_irq_restore(flags);
do {
HMT_low();
if (SHARED_PROCESSOR)
if (is_shared_processor())
__spin_yield(lock);
} while (unlikely(lock->slock != 0));
HMT_medium();
@ -226,7 +238,7 @@ static inline void arch_read_lock(arch_rwlock_t *rw)
break;
do {
HMT_low();
if (SHARED_PROCESSOR)
if (is_shared_processor())
__rw_yield(rw);
} while (unlikely(rw->lock < 0));
HMT_medium();
@ -240,7 +252,7 @@ static inline void arch_write_lock(arch_rwlock_t *rw)
break;
do {
HMT_low();
if (SHARED_PROCESSOR)
if (is_shared_processor())
__rw_yield(rw);
} while (unlikely(rw->lock != 0));
HMT_medium();