From 3aa2591dc2ea292d068dc3a263f1976806c2c281 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Thu, 7 Apr 2016 17:12:23 +0200 Subject: locking/rwsem, xtensa: Drop superfluous arch specific implementation Since "locking, rwsem: drop explicit memory barriers" the arch specific code is basically same as the the generic one so we can drop the superfluous code. Suggested-by: Davidlohr Bueso Signed-off-by: Michal Hocko Acked-by: Max Filippov Cc: Andrew Morton Cc: Chris Zankel Cc: David S. Miller Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Signed-off-by: Davidlohr Bueso Cc: Signed-off-by: Jason Low Cc: Thomas Gleixner Cc: Tony Luck Cc: linux-alpha@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: linux-xtensa@linux-xtensa.org Cc: sparclinux@vger.kernel.org Link: http://lkml.kernel.org/r/1460041951-22347-4-git-send-email-mhocko@kernel.org Signed-off-by: Ingo Molnar --- arch/xtensa/include/asm/Kbuild | 1 + arch/xtensa/include/asm/rwsem.h | 121 ---------------------------------------- 2 files changed, 1 insertion(+), 121 deletions(-) delete mode 100644 arch/xtensa/include/asm/rwsem.h (limited to 'arch/xtensa/include') diff --git a/arch/xtensa/include/asm/Kbuild b/arch/xtensa/include/asm/Kbuild index b56855a1382a..28cf4c5d65ef 100644 --- a/arch/xtensa/include/asm/Kbuild +++ b/arch/xtensa/include/asm/Kbuild @@ -22,6 +22,7 @@ generic-y += mm-arch-hooks.h generic-y += percpu.h generic-y += preempt.h generic-y += resource.h +generic-y += rwsem.h generic-y += sections.h generic-y += siginfo.h generic-y += statfs.h diff --git a/arch/xtensa/include/asm/rwsem.h b/arch/xtensa/include/asm/rwsem.h deleted file mode 100644 index 593483f6e1ff..000000000000 --- a/arch/xtensa/include/asm/rwsem.h +++ /dev/null @@ -1,121 +0,0 @@ -/* - * include/asm-xtensa/rwsem.h - * - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. - * - * Largely copied from include/asm-ppc/rwsem.h - * - * Copyright (C) 2001 - 2005 Tensilica Inc. - */ - -#ifndef _XTENSA_RWSEM_H -#define _XTENSA_RWSEM_H - -#ifndef _LINUX_RWSEM_H -#error "Please don't include directly, use instead." -#endif - -#define RWSEM_UNLOCKED_VALUE 0x00000000 -#define RWSEM_ACTIVE_BIAS 0x00000001 -#define RWSEM_ACTIVE_MASK 0x0000ffff -#define RWSEM_WAITING_BIAS (-0x00010000) -#define RWSEM_ACTIVE_READ_BIAS RWSEM_ACTIVE_BIAS -#define RWSEM_ACTIVE_WRITE_BIAS (RWSEM_WAITING_BIAS + RWSEM_ACTIVE_BIAS) - -/* - * lock for reading - */ -static inline void __down_read(struct rw_semaphore *sem) -{ - if (atomic_add_return(1,(atomic_t *)(&sem->count)) <= 0) - rwsem_down_read_failed(sem); -} - -static inline int __down_read_trylock(struct rw_semaphore *sem) -{ - int tmp; - - while ((tmp = sem->count) >= 0) { - if (tmp == cmpxchg(&sem->count, tmp, - tmp + RWSEM_ACTIVE_READ_BIAS)) { - return 1; - } - } - return 0; -} - -/* - * lock for writing - */ -static inline void __down_write(struct rw_semaphore *sem) -{ - int tmp; - - tmp = atomic_add_return(RWSEM_ACTIVE_WRITE_BIAS, - (atomic_t *)(&sem->count)); - if (tmp != RWSEM_ACTIVE_WRITE_BIAS) - rwsem_down_write_failed(sem); -} - -static inline int __down_write_trylock(struct rw_semaphore *sem) -{ - int tmp; - - tmp = cmpxchg(&sem->count, RWSEM_UNLOCKED_VALUE, - RWSEM_ACTIVE_WRITE_BIAS); - return tmp == RWSEM_UNLOCKED_VALUE; -} - -/* - * unlock after reading - */ -static inline void __up_read(struct rw_semaphore *sem) -{ - int tmp; - - tmp = atomic_sub_return(1,(atomic_t *)(&sem->count)); - if (tmp < -1 && (tmp & RWSEM_ACTIVE_MASK) == 0) - rwsem_wake(sem); -} - -/* - * unlock after writing - */ -static inline void __up_write(struct rw_semaphore *sem) -{ - if (atomic_sub_return(RWSEM_ACTIVE_WRITE_BIAS, - (atomic_t *)(&sem->count)) < 0) - rwsem_wake(sem); -} - -/* - * implement atomic add functionality - */ -static inline void rwsem_atomic_add(int delta, struct rw_semaphore *sem) -{ - atomic_add(delta, (atomic_t *)(&sem->count)); -} - -/* - * downgrade write lock to read lock - */ -static inline void __downgrade_write(struct rw_semaphore *sem) -{ - int tmp; - - tmp = atomic_add_return(-RWSEM_WAITING_BIAS, (atomic_t *)(&sem->count)); - if (tmp < 0) - rwsem_downgrade_wake(sem); -} - -/* - * implement exchange and add functionality - */ -static inline int rwsem_atomic_update(int delta, struct rw_semaphore *sem) -{ - return atomic_add_return(delta, (atomic_t *)(&sem->count)); -} - -#endif /* _XTENSA_RWSEM_H */ -- cgit v1.2.3-55-g7522