arch/openrisc/include/asm/atomic.h

Source file repositories/reference/linux-study-clean/arch/openrisc/include/asm/atomic.h

File Facts

System
Linux kernel
Corpus path
arch/openrisc/include/asm/atomic.h
Extension
.h
Size
3453 bytes
Lines
134
Domain
Architecture Layer
Bucket
arch/openrisc
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef __ASM_OPENRISC_ATOMIC_H
#define __ASM_OPENRISC_ATOMIC_H

#include <linux/types.h>

/* Atomically perform op with v->counter and i */
#define ATOMIC_OP(op)							\
static inline void arch_atomic_##op(int i, atomic_t *v)			\
{									\
	int tmp;							\
									\
	__asm__ __volatile__(						\
		"1:	l.lwa	%0,0(%1)	\n"			\
		"	l." #op " %0,%0,%2	\n"			\
		"	l.swa	0(%1),%0	\n"			\
		"	l.bnf	1b		\n"			\
		"	 l.nop			\n"			\
		: "=&r"(tmp)						\
		: "r"(&v->counter), "r"(i)				\
		: "cc", "memory");					\
}

/* Atomically perform op with v->counter and i, return the result */
#define ATOMIC_OP_RETURN(op)						\
static inline int arch_atomic_##op##_return(int i, atomic_t *v)		\
{									\
	int tmp;							\
									\
	__asm__ __volatile__(						\
		"1:	l.lwa	%0,0(%1)	\n"			\
		"	l." #op " %0,%0,%2	\n"			\
		"	l.swa	0(%1),%0	\n"			\
		"	l.bnf	1b		\n"			\
		"	 l.nop			\n"			\
		: "=&r"(tmp)						\
		: "r"(&v->counter), "r"(i)				\
		: "cc", "memory");					\
									\
	return tmp;							\
}

/* Atomically perform op with v->counter and i, return orig v->counter */
#define ATOMIC_FETCH_OP(op)						\
static inline int arch_atomic_fetch_##op(int i, atomic_t *v)		\
{									\
	int tmp, old;							\
									\
	__asm__ __volatile__(						\
		"1:	l.lwa	%0,0(%2)	\n"			\
		"	l." #op " %1,%0,%3	\n"			\
		"	l.swa	0(%2),%1	\n"			\
		"	l.bnf	1b		\n"			\
		"	 l.nop			\n"			\
		: "=&r"(old), "=&r"(tmp)				\
		: "r"(&v->counter), "r"(i)				\
		: "cc", "memory");					\
									\
	return old;							\
}

ATOMIC_OP_RETURN(add)
ATOMIC_OP_RETURN(sub)

ATOMIC_FETCH_OP(add)
ATOMIC_FETCH_OP(sub)
ATOMIC_FETCH_OP(and)
ATOMIC_FETCH_OP(or)
ATOMIC_FETCH_OP(xor)

ATOMIC_OP(add)
ATOMIC_OP(sub)
ATOMIC_OP(and)
ATOMIC_OP(or)
ATOMIC_OP(xor)

#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

#define arch_atomic_add_return	arch_atomic_add_return
#define arch_atomic_sub_return	arch_atomic_sub_return
#define arch_atomic_fetch_add	arch_atomic_fetch_add
#define arch_atomic_fetch_sub	arch_atomic_fetch_sub
#define arch_atomic_fetch_and	arch_atomic_fetch_and
#define arch_atomic_fetch_or	arch_atomic_fetch_or
#define arch_atomic_fetch_xor	arch_atomic_fetch_xor
#define arch_atomic_add		arch_atomic_add
#define arch_atomic_sub		arch_atomic_sub
#define arch_atomic_and		arch_atomic_and
#define arch_atomic_or		arch_atomic_or

Annotation

Implementation Notes