From: Rik Van Riel Add sem_is_read/write_locked functions to the read/write semaphores, along the same lines of the *_is_locked spinlock functions. The swap token tuning patch uses sem_is_read_locked; sem_is_write_locked is added for completeness. Signed-off-by: Rik van Riel Signed-off-by: Andrew Morton --- include/asm-alpha/rwsem.h | 10 ++++++++++ include/asm-i386/rwsem.h | 10 ++++++++++ include/asm-ia64/rwsem.h | 10 ++++++++++ include/asm-ppc/rwsem.h | 10 ++++++++++ include/asm-ppc64/rwsem.h | 10 ++++++++++ include/asm-s390/rwsem.h | 10 ++++++++++ include/asm-sh/rwsem.h | 10 ++++++++++ include/asm-sparc64/rwsem.h | 10 ++++++++++ include/asm-x86_64/rwsem.h | 10 ++++++++++ include/linux/rwsem-spinlock.h | 10 ++++++++++ 10 files changed, 100 insertions(+) diff -puN include/asm-alpha/rwsem.h~add-sem_is_read-write_locked include/asm-alpha/rwsem.h --- 25/include/asm-alpha/rwsem.h~add-sem_is_read-write_locked Tue Jun 28 15:42:30 2005 +++ 25-akpm/include/asm-alpha/rwsem.h Tue Jun 28 15:42:30 2005 @@ -262,5 +262,15 @@ static inline long rwsem_atomic_update(l #endif } +static inline int sem_is_read_locked(struct rw_semaphore *sem) +{ + return (sem->count > 0); +} + +static inline int sem_is_write_locked(struct rw_semaphore *sem) +{ + return (sem->count < 0); +} + #endif /* __KERNEL__ */ #endif /* _ALPHA_RWSEM_H */ diff -puN include/asm-i386/rwsem.h~add-sem_is_read-write_locked include/asm-i386/rwsem.h --- 25/include/asm-i386/rwsem.h~add-sem_is_read-write_locked Tue Jun 28 15:42:30 2005 +++ 25-akpm/include/asm-i386/rwsem.h Tue Jun 28 15:42:30 2005 @@ -284,5 +284,15 @@ LOCK_PREFIX "xadd %0,(%2)" return tmp+delta; } +static inline int sem_is_read_locked(struct rw_semaphore *sem) +{ + return (sem->count > 0); +} + +static inline int sem_is_write_locked(struct rw_semaphore *sem) +{ + return (sem->count < 0); +} + #endif /* __KERNEL__ */ #endif /* _I386_RWSEM_H */ diff -puN include/asm-ia64/rwsem.h~add-sem_is_read-write_locked include/asm-ia64/rwsem.h --- 25/include/asm-ia64/rwsem.h~add-sem_is_read-write_locked Tue Jun 28 15:42:30 2005 +++ 25-akpm/include/asm-ia64/rwsem.h Tue Jun 28 15:42:30 2005 @@ -185,4 +185,14 @@ __downgrade_write (struct rw_semaphore * #define rwsem_atomic_add(delta, sem) atomic_add(delta, (atomic_t *)(&(sem)->count)) #define rwsem_atomic_update(delta, sem) atomic_add_return(delta, (atomic_t *)(&(sem)->count)) +static inline int sem_is_read_locked(struct rw_semaphore *sem) +{ + return (sem->count > 0); +} + +static inline int sem_is_write_locked(struct rw_semaphore *sem) +{ + return (sem->count < 0); +} + #endif /* _ASM_IA64_RWSEM_H */ diff -puN include/asm-ppc64/rwsem.h~add-sem_is_read-write_locked include/asm-ppc64/rwsem.h --- 25/include/asm-ppc64/rwsem.h~add-sem_is_read-write_locked Tue Jun 28 15:42:30 2005 +++ 25-akpm/include/asm-ppc64/rwsem.h Tue Jun 28 15:42:30 2005 @@ -163,5 +163,15 @@ static inline int rwsem_atomic_update(in return atomic_add_return(delta, (atomic_t *)(&sem->count)); } +static inline int sem_is_read_locked(struct rw_semaphore *sem) +{ + return (sem->count > 0); +} + +static inline int sem_is_write_locked(struct rw_semaphore *sem) +{ + return (sem->count < 0); +} + #endif /* __KERNEL__ */ #endif /* _PPC_RWSEM_XADD_H */ diff -puN include/asm-ppc/rwsem.h~add-sem_is_read-write_locked include/asm-ppc/rwsem.h --- 25/include/asm-ppc/rwsem.h~add-sem_is_read-write_locked Tue Jun 28 15:42:30 2005 +++ 25-akpm/include/asm-ppc/rwsem.h Tue Jun 28 15:42:30 2005 @@ -168,5 +168,15 @@ static inline int rwsem_atomic_update(in return atomic_add_return(delta, (atomic_t *)(&sem->count)); } +static inline int sem_is_read_locked(struct rw_semaphore *sem) +{ + return (sem->count > 0); +} + +static inline int sem_is_write_locked(struct rw_semaphore *sem) +{ + return (sem->count < 0); +} + #endif /* __KERNEL__ */ #endif /* _PPC_RWSEM_XADD_H */ diff -puN include/asm-s390/rwsem.h~add-sem_is_read-write_locked include/asm-s390/rwsem.h --- 25/include/asm-s390/rwsem.h~add-sem_is_read-write_locked Tue Jun 28 15:42:30 2005 +++ 25-akpm/include/asm-s390/rwsem.h Tue Jun 28 15:42:30 2005 @@ -351,5 +351,15 @@ static inline long rwsem_atomic_update(l return new; } +static inline int sem_is_read_locked(struct rw_semaphore *sem) +{ + return (sem->count > 0); +} + +static inline int sem_is_write_locked(struct rw_semaphore *sem) +{ + return (sem->count < 0); +} + #endif /* __KERNEL__ */ #endif /* _S390_RWSEM_H */ diff -puN include/asm-sh/rwsem.h~add-sem_is_read-write_locked include/asm-sh/rwsem.h --- 25/include/asm-sh/rwsem.h~add-sem_is_read-write_locked Tue Jun 28 15:42:30 2005 +++ 25-akpm/include/asm-sh/rwsem.h Tue Jun 28 15:42:30 2005 @@ -166,5 +166,15 @@ static inline int rwsem_atomic_update(in return atomic_add_return(delta, (atomic_t *)(&sem->count)); } +static inline int sem_is_read_locked(struct rw_semaphore *sem) +{ + return (sem->count > 0); +} + +static inline int sem_is_write_locked(struct rw_semaphore *sem) +{ + return (sem->count < 0); +} + #endif /* __KERNEL__ */ #endif /* _ASM_SH_RWSEM_H */ diff -puN include/asm-sparc64/rwsem.h~add-sem_is_read-write_locked include/asm-sparc64/rwsem.h --- 25/include/asm-sparc64/rwsem.h~add-sem_is_read-write_locked Tue Jun 28 15:42:30 2005 +++ 25-akpm/include/asm-sparc64/rwsem.h Tue Jun 28 15:42:30 2005 @@ -96,6 +96,16 @@ static __inline__ signed long rwsem_cmpx return cmpxchg(&sem->count,old,new); } +static inline int sem_is_read_locked(struct rw_semaphore *sem) +{ + return (sem->count > 0); +} + +static inline int sem_is_write_locked(struct rw_semaphore *sem) +{ + return (sem->count < 0); +} + #endif /* __KERNEL__ */ #endif /* _SPARC64_RWSEM_H */ diff -puN include/asm-x86_64/rwsem.h~add-sem_is_read-write_locked include/asm-x86_64/rwsem.h --- 25/include/asm-x86_64/rwsem.h~add-sem_is_read-write_locked Tue Jun 28 15:42:30 2005 +++ 25-akpm/include/asm-x86_64/rwsem.h Tue Jun 28 15:42:30 2005 @@ -274,5 +274,15 @@ LOCK_PREFIX "xaddl %0,(%2)" return tmp+delta; } +static inline int sem_is_read_locked(struct rw_semaphore *sem) +{ + return (sem->count > 0); +} + +static inline int sem_is_write_locked(struct rw_semaphore *sem) +{ + return (sem->count < 0); +} + #endif /* __KERNEL__ */ #endif /* _X8664_RWSEM_H */ diff -puN include/linux/rwsem-spinlock.h~add-sem_is_read-write_locked include/linux/rwsem-spinlock.h --- 25/include/linux/rwsem-spinlock.h~add-sem_is_read-write_locked Tue Jun 28 15:42:30 2005 +++ 25-akpm/include/linux/rwsem-spinlock.h Tue Jun 28 15:42:30 2005 @@ -61,5 +61,15 @@ extern void FASTCALL(__up_read(struct rw extern void FASTCALL(__up_write(struct rw_semaphore *sem)); extern void FASTCALL(__downgrade_write(struct rw_semaphore *sem)); +static inline int sem_is_read_locked(struct rw_semaphore *sem) +{ + return (sem->activity > 0); +} + +static inline int sem_is_write_locked(struct rw_semaphore *sem) +{ + return (sem->activity < 0); +} + #endif /* __KERNEL__ */ #endif /* _LINUX_RWSEM_SPINLOCK_H */ _