On Thu, 2016-06-02 at 17:22 +0800, Pan Xinhui wrote: > Base code to enable qspinlock on powerpc. this patch add some #ifdef > here and there. Although there is no paravirt related code, we can > successfully build a qspinlock kernel after apply this patch. This is missing the IO_SYNC stuff ... It means we'll fail to do a full sync to order vs MMIOs. You need to add that back in the unlock path. > Signed-off-by: Pan Xinhui <xinhui.pan@xxxxxxxxxxxxxxxxxx> > --- > arch/powerpc/include/asm/qspinlock.h | 26 > ++++++++++++++++++++++++++ > arch/powerpc/include/asm/spinlock.h | 27 +++++++++++++++---- > -------- > arch/powerpc/include/asm/spinlock_types.h | 4 ++++ > arch/powerpc/lib/locks.c | 4 ++++ > 4 files changed, 49 insertions(+), 12 deletions(-) > create mode 100644 arch/powerpc/include/asm/qspinlock.h > > diff --git a/arch/powerpc/include/asm/qspinlock.h > b/arch/powerpc/include/asm/qspinlock.h > new file mode 100644 > index 0000000..fc83cd2 > --- /dev/null > +++ b/arch/powerpc/include/asm/qspinlock.h > @@ -0,0 +1,26 @@ > +#ifndef _ASM_POWERPC_QSPINLOCK_H > +#define _ASM_POWERPC_QSPINLOCK_H > + > +#include <asm-generic/qspinlock_types.h> > + > +#define SPIN_THRESHOLD (1 << 15) > +#define queued_spin_unlock queued_spin_unlock > + > +static inline void native_queued_spin_unlock(struct qspinlock *lock) > +{ > + u8 *locked = (u8 *)lock; > +#ifdef __BIG_ENDIAN > + locked += 3; > +#endif > + /* no load/store can be across the unlock()*/ > + smp_store_release(locked, 0); > +} > + > +static inline void queued_spin_unlock(struct qspinlock *lock) > +{ > + native_queued_spin_unlock(lock); > +} > + > +#include <asm-generic/qspinlock.h> > + > +#endif /* _ASM_POWERPC_QSPINLOCK_H */ > diff --git a/arch/powerpc/include/asm/spinlock.h > b/arch/powerpc/include/asm/spinlock.h > index 523673d..4359ee6 100644 > --- a/arch/powerpc/include/asm/spinlock.h > +++ b/arch/powerpc/include/asm/spinlock.h > @@ -52,6 +52,20 @@ > #define SYNC_IO > #endif > > +#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 > + > +#ifdef CONFIG_QUEUED_SPINLOCKS > +#include <asm/qspinlock.h> > +#else > static __always_inline int arch_spin_value_unlocked(arch_spinlock_t > lock) > { > return lock.slock == 0; > @@ -106,18 +120,6 @@ static inline int > arch_spin_trylock(arch_spinlock_t *lock) > * held. Conveniently, we have a word in the paca that holds this > * value. > */ > - > -#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 void arch_spin_lock(arch_spinlock_t *lock) > { > CLEAR_IO_SYNC; > @@ -169,6 +171,7 @@ extern void arch_spin_unlock_wait(arch_spinlock_t > *lock); > do { while (arch_spin_is_locked(lock)) cpu_relax(); } while > (0) > #endif > > +#endif /* !CONFIG_QUEUED_SPINLOCKS */ > /* > * Read-write spinlocks, allowing multiple readers > * but only one writer. > diff --git a/arch/powerpc/include/asm/spinlock_types.h > b/arch/powerpc/include/asm/spinlock_types.h > index 2351adc..bd7144e 100644 > --- a/arch/powerpc/include/asm/spinlock_types.h > +++ b/arch/powerpc/include/asm/spinlock_types.h > @@ -5,11 +5,15 @@ > # error "please don't include this file directly" > #endif > > +#ifdef CONFIG_QUEUED_SPINLOCKS > +#include <asm-generic/qspinlock_types.h> > +#else > typedef struct { > volatile unsigned int slock; > } arch_spinlock_t; > > #define __ARCH_SPIN_LOCK_UNLOCKED { 0 } > +#endif > > typedef struct { > volatile signed int lock; > diff --git a/arch/powerpc/lib/locks.c b/arch/powerpc/lib/locks.c > index f7deebd..a9ebd71 100644 > --- a/arch/powerpc/lib/locks.c > +++ b/arch/powerpc/lib/locks.c > @@ -23,6 +23,7 @@ > #include <asm/hvcall.h> > #include <asm/smp.h> > > +#ifndef CONFIG_QUEUED_SPINLOCKS > void __spin_yield(arch_spinlock_t *lock) > { > unsigned int lock_value, holder_cpu, yield_count; > @@ -42,6 +43,7 @@ void __spin_yield(arch_spinlock_t *lock) > get_hard_smp_processor_id(holder_cpu), yield_count); > } > EXPORT_SYMBOL_GPL(__spin_yield); > +#endif > > /* > * Waiting for a read lock or a write lock on a rwlock... > @@ -69,6 +71,7 @@ void __rw_yield(arch_rwlock_t *rw) > } > #endif > > +#ifndef CONFIG_QUEUED_SPINLOCKS > void arch_spin_unlock_wait(arch_spinlock_t *lock) > { > smp_mb(); > @@ -84,3 +87,4 @@ void arch_spin_unlock_wait(arch_spinlock_t *lock) > } > > EXPORT_SYMBOL(arch_spin_unlock_wait); > +#endif _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization