mmu_context.h

嵌入式系统设计与实验教材二源码linux内核移植与编译

/*
 *  linux/include/asm-arm/mmu_context.h
 *
 *  Copyright (C) 1996 Russell King.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *  Changelog:
 *   27-06-1996	RMK	Created
 */
#ifndef __ASM_ARM_MMU_CONTEXT_H
#define __ASM_ARM_MMU_CONTEXT_H

#include <asm/bitops.h>
#include <asm/pgtable.h>
#include <asm/arch/memory.h>
#include <asm/proc-fns.h>

#define destroy_context(mm)		do { } while(0)
#define init_new_context(tsk,mm)	0

/*
 * This is called when "tsk" is about to enter lazy TLB mode.
 *
 * mm:  describes the currently active mm context
 * tsk: task which is entering lazy tlb
 * cpu: cpu number which is entering lazy tlb
 *
 * tsk->mm will be NULL
 */
static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk, unsigned cpu)
{
}

/*
 * This is the actual mm switch as far as the scheduler
 * is concerned.  No registers are touched.
 */
static inline void
switch_mm(struct mm_struct *prev, struct mm_struct *next,
	  struct task_struct *tsk, unsigned int cpu)
{
	if (prev != next)
		cpu_switch_mm(next->pgd, tsk);
}

#define activate_mm(prev, next) \
	switch_mm((prev),(next),NULL,smp_processor_id())

#endif