There is no agreed-upon definition of spin_unlock_wait()'s semantics, and it appears that all callers could do just as well with a lock/unlock pair. This commit therefore removes the underlying arch-specific arch_spin_unlock_wait(). Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> Cc: Chris Metcalf <cmetcalf@xxxxxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Cc: Andrea Parri <parri.andrea@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> --- arch/tile/include/asm/spinlock_32.h | 2 -- arch/tile/include/asm/spinlock_64.h | 2 -- arch/tile/lib/spinlock_32.c | 23 ----------------------- arch/tile/lib/spinlock_64.c | 22 ---------------------- 4 files changed, 49 deletions(-) diff --git a/arch/tile/include/asm/spinlock_32.h b/arch/tile/include/asm/spinlock_32.h index b14b1ba5bf9c..cba8ba9b8da6 100644 --- a/arch/tile/include/asm/spinlock_32.h +++ b/arch/tile/include/asm/spinlock_32.h @@ -64,8 +64,6 @@ static inline void arch_spin_unlock(arch_spinlock_t *lock) lock->current_ticket = old_ticket + TICKET_QUANTUM; } -void arch_spin_unlock_wait(arch_spinlock_t *lock); - /* * Read-write spinlocks, allowing multiple readers * but only one writer. diff --git a/arch/tile/include/asm/spinlock_64.h b/arch/tile/include/asm/spinlock_64.h index b9718fb4e74a..9a2c2d605752 100644 --- a/arch/tile/include/asm/spinlock_64.h +++ b/arch/tile/include/asm/spinlock_64.h @@ -58,8 +58,6 @@ static inline void arch_spin_unlock(arch_spinlock_t *lock) __insn_fetchadd4(&lock->lock, 1U << __ARCH_SPIN_CURRENT_SHIFT); } -void arch_spin_unlock_wait(arch_spinlock_t *lock); - void arch_spin_lock_slow(arch_spinlock_t *lock, u32 val); /* Grab the "next" ticket number and bump it atomically. diff --git a/arch/tile/lib/spinlock_32.c b/arch/tile/lib/spinlock_32.c index 076c6cc43113..db9333f2447c 100644 --- a/arch/tile/lib/spinlock_32.c +++ b/arch/tile/lib/spinlock_32.c @@ -62,29 +62,6 @@ int arch_spin_trylock(arch_spinlock_t *lock) } EXPORT_SYMBOL(arch_spin_trylock); -void arch_spin_unlock_wait(arch_spinlock_t *lock) -{ - u32 iterations = 0; - int curr = READ_ONCE(lock->current_ticket); - int next = READ_ONCE(lock->next_ticket); - - /* Return immediately if unlocked. */ - if (next == curr) - return; - - /* Wait until the current locker has released the lock. */ - do { - delay_backoff(iterations++); - } while (READ_ONCE(lock->current_ticket) == curr); - - /* - * The TILE architecture doesn't do read speculation; therefore - * a control dependency guarantees a LOAD->{LOAD,STORE} order. - */ - barrier(); -} -EXPORT_SYMBOL(arch_spin_unlock_wait); - /* * The low byte is always reserved to be the marker for a "tns" operation * since the low bit is set to "1" by a tns. The next seven bits are diff --git a/arch/tile/lib/spinlock_64.c b/arch/tile/lib/spinlock_64.c index a4b5b2cbce93..de414c22892f 100644 --- a/arch/tile/lib/spinlock_64.c +++ b/arch/tile/lib/spinlock_64.c @@ -62,28 +62,6 @@ int arch_spin_trylock(arch_spinlock_t *lock) } EXPORT_SYMBOL(arch_spin_trylock); -void arch_spin_unlock_wait(arch_spinlock_t *lock) -{ - u32 iterations = 0; - u32 val = READ_ONCE(lock->lock); - u32 curr = arch_spin_current(val); - - /* Return immediately if unlocked. */ - if (arch_spin_next(val) == curr) - return; - - /* Wait until the current locker has released the lock. */ - do { - delay_backoff(iterations++); - } while (arch_spin_current(READ_ONCE(lock->lock)) == curr); - - /* - * The TILE architecture doesn't do read speculation; therefore - * a control dependency guarantees a LOAD->{LOAD,STORE} order. - */ - barrier(); -} -EXPORT_SYMBOL(arch_spin_unlock_wait); /* * If the read lock fails due to a writer, we retry periodically -- 2.5.2