mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-17 01:04:19 +08:00
d6dd61c831
Add hooks to allow a paravirt implementation to track the lifetime of an mm. Paravirtualization requires three hooks, but only two are needed in common code. They are: arch_dup_mmap, which is called when a new mmap is created at fork arch_exit_mmap, which is called when the last process reference to an mm is dropped, which typically happens on exit and exec. The third hook is activate_mm, which is called from the arch-specific activate_mm() macro/function, and so doesn't need stub versions for other architectures. It's called when an mm is first used. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: linux-arch@vger.kernel.org Cc: James Bottomley <James.Bottomley@SteelEye.com> Acked-by: Ingo Molnar <mingo@elte.hu>
51 lines
1.4 KiB
C
51 lines
1.4 KiB
C
/* mmu_context.h: MMU context management routines
|
|
*
|
|
* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the License, or (at your option) any later version.
|
|
*/
|
|
|
|
#ifndef _ASM_MMU_CONTEXT_H
|
|
#define _ASM_MMU_CONTEXT_H
|
|
|
|
#include <asm/setup.h>
|
|
#include <asm/page.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm-generic/mm_hooks.h>
|
|
|
|
static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
|
|
{
|
|
}
|
|
|
|
#ifdef CONFIG_MMU
|
|
extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
|
|
extern void change_mm_context(mm_context_t *old, mm_context_t *ctx, pgd_t *_pgd);
|
|
extern void destroy_context(struct mm_struct *mm);
|
|
|
|
#else
|
|
#define init_new_context(tsk, mm) ({ 0; })
|
|
#define change_mm_context(old, ctx, _pml4) do {} while(0)
|
|
#define destroy_context(mm) do {} while(0)
|
|
#endif
|
|
|
|
#define switch_mm(prev, next, tsk) \
|
|
do { \
|
|
if (prev != next) \
|
|
change_mm_context(&prev->context, &next->context, next->pgd); \
|
|
} while(0)
|
|
|
|
#define activate_mm(prev, next) \
|
|
do { \
|
|
change_mm_context(&prev->context, &next->context, next->pgd); \
|
|
} while(0)
|
|
|
|
#define deactivate_mm(tsk, mm) \
|
|
do { \
|
|
} while(0)
|
|
|
|
#endif
|