linux/arch/csky/include/asm/spinlock.h

/* SPDX-License-Identifier: GPL-2.0 */

#ifndef __ASM_CSKY_SPINLOCK_H
#define __ASM_CSKY_SPINLOCK_H

#include <asm/qspinlock.h>
#include <asm/qrwlock.h>

/* See include/linux/spinlock.h */
#define smp_mb__after_spinlock()	smp_mb()

#endif /* __ASM_CSKY_SPINLOCK_H */
csky: Add qspinlock support Enable qspinlock by the requirements mentioned in a8ad07e5240c9 ("asm-generic: qspinlock: Indicate the use of mixed-size atomics"). C-SKY only has "ldex/stex" for all atomic operations. So csky give a strong forward guarantee for "ldex/stex." That means when ldex grabbed the cache line into $L1, it would block other cores from snooping the address with several cycles. The atomic_fetch_add & xchg16 has the same forward guarantee level in C-SKY. Qspinlock has better code size and performance in a fast path. Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@kernel.org> 2022-07-23 21:32:34 -04:00			`/* SPDX-License-Identifier: GPL-2.0 */`

			`#ifndef __ASM_CSKY_SPINLOCK_H`
			`#define __ASM_CSKY_SPINLOCK_H`

			`#include <asm/qspinlock.h>`
			`#include <asm/qrwlock.h>`

			`/* See include/linux/spinlock.h */`
			`#define smp_mb__after_spinlock() smp_mb()`

			`#endif /* __ASM_CSKY_SPINLOCK_H */`