ia64/linux-2.6.18-xen.hg

view include/asm-arm/mmu_context.h @ 452:c7ed6fe5dca0

kexec: dont initialise regions in reserve_memory()

There is no need to initialise efi_memmap_res and boot_param_res in
reserve_memory() for the initial xen domain as it is done in
machine_kexec_setup_resources() using values from the kexec hypercall.

Signed-off-by: Simon Horman <horms@verge.net.au>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Feb 28 10:55:18 2008 +0000 (2008-02-28)
parents 831230e53067
children
line source
1 /*
2 * linux/include/asm-arm/mmu_context.h
3 *
4 * Copyright (C) 1996 Russell King.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * Changelog:
11 * 27-06-1996 RMK Created
12 */
13 #ifndef __ASM_ARM_MMU_CONTEXT_H
14 #define __ASM_ARM_MMU_CONTEXT_H
16 #include <linux/compiler.h>
17 #include <asm/cacheflush.h>
18 #include <asm/proc-fns.h>
20 void __check_kvm_seq(struct mm_struct *mm);
22 #if __LINUX_ARM_ARCH__ >= 6
24 /*
25 * On ARMv6, we have the following structure in the Context ID:
26 *
27 * 31 7 0
28 * +-------------------------+-----------+
29 * | process ID | ASID |
30 * +-------------------------+-----------+
31 * | context ID |
32 * +-------------------------------------+
33 *
34 * The ASID is used to tag entries in the CPU caches and TLBs.
35 * The context ID is used by debuggers and trace logic, and
36 * should be unique within all running processes.
37 */
38 #define ASID_BITS 8
39 #define ASID_MASK ((~0) << ASID_BITS)
41 extern unsigned int cpu_last_asid;
43 void __init_new_context(struct task_struct *tsk, struct mm_struct *mm);
44 void __new_context(struct mm_struct *mm);
46 static inline void check_context(struct mm_struct *mm)
47 {
48 if (unlikely((mm->context.id ^ cpu_last_asid) >> ASID_BITS))
49 __new_context(mm);
51 if (unlikely(mm->context.kvm_seq != init_mm.context.kvm_seq))
52 __check_kvm_seq(mm);
53 }
55 #define init_new_context(tsk,mm) (__init_new_context(tsk,mm),0)
57 #else
59 static inline void check_context(struct mm_struct *mm)
60 {
61 if (unlikely(mm->context.kvm_seq != init_mm.context.kvm_seq))
62 __check_kvm_seq(mm);
63 }
65 #define init_new_context(tsk,mm) 0
67 #endif
69 #define destroy_context(mm) do { } while(0)
71 /*
72 * This is called when "tsk" is about to enter lazy TLB mode.
73 *
74 * mm: describes the currently active mm context
75 * tsk: task which is entering lazy tlb
76 * cpu: cpu number which is entering lazy tlb
77 *
78 * tsk->mm will be NULL
79 */
80 static inline void
81 enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
82 {
83 }
85 /*
86 * This is the actual mm switch as far as the scheduler
87 * is concerned. No registers are touched. We avoid
88 * calling the CPU specific function when the mm hasn't
89 * actually changed.
90 */
91 static inline void
92 switch_mm(struct mm_struct *prev, struct mm_struct *next,
93 struct task_struct *tsk)
94 {
95 #ifdef CONFIG_MMU
96 unsigned int cpu = smp_processor_id();
98 if (prev != next) {
99 cpu_set(cpu, next->cpu_vm_mask);
100 check_context(next);
101 cpu_switch_mm(next->pgd, next);
102 if (cache_is_vivt())
103 cpu_clear(cpu, prev->cpu_vm_mask);
104 }
105 #endif
106 }
108 #define deactivate_mm(tsk,mm) do { } while (0)
109 #define activate_mm(prev,next) switch_mm(prev, next, NULL)
111 #endif