From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Hocko Date: Mon, 04 Apr 2016 09:06:40 +0000 Subject: [PATCH 2/2] sh, rwsem: drop superfluous arch specific implementation Message-Id: <1459760800-13477-2-git-send-email-mhocko@kernel.org> List-Id: References: <20160404090335.GB10272@dhcp22.suse.cz> <1459760800-13477-1-git-send-email-mhocko@kernel.org> In-Reply-To: <1459760800-13477-1-git-send-email-mhocko@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: LKML Cc: Peter Zijlstra , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , "David S. Miller" , Tony Luck , Andrew Morton , Chris Zankel , Max Filippov , x86@kernel.org, linux-alpha@vger.kernel.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-xtensa@linux-xtensa.org, linux-arch@vger.kernel.org, Michal Hocko From: Michal Hocko 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 --- arch/sh/include/asm/Kbuild | 1 + arch/sh/include/asm/rwsem.h | 130 -------------------------------------------- 2 files changed, 1 insertion(+), 130 deletions(-) delete mode 100644 arch/sh/include/asm/rwsem.h diff --git a/arch/sh/include/asm/Kbuild b/arch/sh/include/asm/Kbuild index aac452b26aa8..6d866c7a9b74 100644 --- a/arch/sh/include/asm/Kbuild +++ b/arch/sh/include/asm/Kbuild @@ -25,6 +25,7 @@ generic-y += percpu.h generic-y += poll.h generic-y += preempt.h generic-y += resource.h +generic-y += rwsem.h generic-y += sembuf.h generic-y += serial.h generic-y += shmbuf.h diff --git a/arch/sh/include/asm/rwsem.h b/arch/sh/include/asm/rwsem.h deleted file mode 100644 index 8a457b83d2a5..000000000000 --- a/arch/sh/include/asm/rwsem.h +++ /dev/null @@ -1,130 +0,0 @@ -/* - * include/asm-sh/rwsem.h: R/W semaphores for SH using the stuff - * in lib/rwsem.c. - */ - -#ifndef _ASM_SH_RWSEM_H -#define _ASM_SH_RWSEM_H - -#ifndef _LINUX_RWSEM_H -#error "please don't include asm/rwsem.h directly, use linux/rwsem.h instead" -#endif - -#ifdef __KERNEL__ - -#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_inc_return((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_killable(struct rw_semaphore *sem) -{ - int tmp; - - tmp = atomic_add_return(RWSEM_ACTIVE_WRITE_BIAS, - (atomic_t *)(&sem->count)); - if (tmp != RWSEM_ACTIVE_WRITE_BIAS) - if (IS_ERR(rwsem_down_write_failed_killable(sem))) - return -EINTR; - - return 0; -} - -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_dec_return((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 /* __KERNEL__ */ -#endif /* _ASM_SH_RWSEM_H */ -- 2.8.0.rc3 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932172AbcDDJHB (ORCPT ); Mon, 4 Apr 2016 05:07:01 -0400 Received: from mail-lf0-f66.google.com ([209.85.215.66]:32944 "EHLO mail-lf0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754822AbcDDJG5 (ORCPT ); Mon, 4 Apr 2016 05:06:57 -0400 From: Michal Hocko To: LKML Cc: Peter Zijlstra , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , "David S. Miller" , Tony Luck , Andrew Morton , Chris Zankel , Max Filippov , x86@kernel.org, linux-alpha@vger.kernel.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-xtensa@linux-xtensa.org, linux-arch@vger.kernel.org, Michal Hocko Subject: [PATCH 2/2] sh, rwsem: drop superfluous arch specific implementation Date: Mon, 4 Apr 2016 11:06:40 +0200 Message-Id: <1459760800-13477-2-git-send-email-mhocko@kernel.org> X-Mailer: git-send-email 2.8.0.rc3 In-Reply-To: <1459760800-13477-1-git-send-email-mhocko@kernel.org> References: <20160404090335.GB10272@dhcp22.suse.cz> <1459760800-13477-1-git-send-email-mhocko@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michal Hocko 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 --- arch/sh/include/asm/Kbuild | 1 + arch/sh/include/asm/rwsem.h | 130 -------------------------------------------- 2 files changed, 1 insertion(+), 130 deletions(-) delete mode 100644 arch/sh/include/asm/rwsem.h diff --git a/arch/sh/include/asm/Kbuild b/arch/sh/include/asm/Kbuild index aac452b26aa8..6d866c7a9b74 100644 --- a/arch/sh/include/asm/Kbuild +++ b/arch/sh/include/asm/Kbuild @@ -25,6 +25,7 @@ generic-y += percpu.h generic-y += poll.h generic-y += preempt.h generic-y += resource.h +generic-y += rwsem.h generic-y += sembuf.h generic-y += serial.h generic-y += shmbuf.h diff --git a/arch/sh/include/asm/rwsem.h b/arch/sh/include/asm/rwsem.h deleted file mode 100644 index 8a457b83d2a5..000000000000 --- a/arch/sh/include/asm/rwsem.h +++ /dev/null @@ -1,130 +0,0 @@ -/* - * include/asm-sh/rwsem.h: R/W semaphores for SH using the stuff - * in lib/rwsem.c. - */ - -#ifndef _ASM_SH_RWSEM_H -#define _ASM_SH_RWSEM_H - -#ifndef _LINUX_RWSEM_H -#error "please don't include asm/rwsem.h directly, use linux/rwsem.h instead" -#endif - -#ifdef __KERNEL__ - -#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_inc_return((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_killable(struct rw_semaphore *sem) -{ - int tmp; - - tmp = atomic_add_return(RWSEM_ACTIVE_WRITE_BIAS, - (atomic_t *)(&sem->count)); - if (tmp != RWSEM_ACTIVE_WRITE_BIAS) - if (IS_ERR(rwsem_down_write_failed_killable(sem))) - return -EINTR; - - return 0; -} - -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_dec_return((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 /* __KERNEL__ */ -#endif /* _ASM_SH_RWSEM_H */ -- 2.8.0.rc3