arch/powerpc/include/asm/local.h

Source file repositories/reference/linux-study-clean/arch/powerpc/include/asm/local.h

File Facts

System
Linux kernel
Corpus path
arch/powerpc/include/asm/local.h
Extension
.h
Size
3442 bytes
Lines
160
Domain
Architecture Layer
Bucket
arch/powerpc
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 _ARCH_POWERPC_LOCAL_H
#define _ARCH_POWERPC_LOCAL_H

#ifdef CONFIG_PPC_BOOK3S_64

#include <linux/percpu.h>
#include <linux/atomic.h>
#include <linux/irqflags.h>

#include <asm/hw_irq.h>

typedef struct
{
	long v;
} local_t;

#define LOCAL_INIT(i)	{ (i) }

static __inline__ long local_read(const local_t *l)
{
	return READ_ONCE(l->v);
}

static __inline__ void local_set(local_t *l, long i)
{
	WRITE_ONCE(l->v, i);
}

#define LOCAL_OP(op, c_op)						\
static __inline__ void local_##op(long i, local_t *l)			\
{									\
	unsigned long flags;						\
									\
	powerpc_local_irq_pmu_save(flags);				\
	l->v c_op i;						\
	powerpc_local_irq_pmu_restore(flags);				\
}

#define LOCAL_OP_RETURN(op, c_op)					\
static __inline__ long local_##op##_return(long a, local_t *l)		\
{									\
	long t;								\
	unsigned long flags;						\
									\
	powerpc_local_irq_pmu_save(flags);				\
	t = (l->v c_op a);						\
	powerpc_local_irq_pmu_restore(flags);				\
									\
	return t;							\
}

#define LOCAL_OPS(op, c_op)		\
	LOCAL_OP(op, c_op)		\
	LOCAL_OP_RETURN(op, c_op)

LOCAL_OPS(add, +=)
LOCAL_OPS(sub, -=)

#define local_add_negative(a, l)	(local_add_return((a), (l)) < 0)
#define local_inc_return(l)		local_add_return(1LL, l)
#define local_inc(l)			local_inc_return(l)

/*
 * local_inc_and_test - increment and test
 * @l: pointer of type local_t
 *
 * Atomically increments @l by 1
 * and returns true if the result is zero, or false for all
 * other cases.
 */
#define local_inc_and_test(l)		(local_inc_return(l) == 0)

#define local_dec_return(l)		local_sub_return(1LL, l)
#define local_dec(l)			local_dec_return(l)
#define local_sub_and_test(a, l)	(local_sub_return((a), (l)) == 0)
#define local_dec_and_test(l)		(local_dec_return((l)) == 0)

static __inline__ long local_cmpxchg(local_t *l, long o, long n)
{
	long t;
	unsigned long flags;

	powerpc_local_irq_pmu_save(flags);
	t = l->v;
	if (t == o)
		l->v = n;
	powerpc_local_irq_pmu_restore(flags);

	return t;
}

Annotation

Implementation Notes