diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-arm/mmu_context.h |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-arm/mmu_context.h')
-rw-r--r-- | include/asm-arm/mmu_context.h | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/include/asm-arm/mmu_context.h b/include/asm-arm/mmu_context.h new file mode 100644 index 000000000000..4af9c411c617 --- /dev/null +++ b/include/asm-arm/mmu_context.h | |||
@@ -0,0 +1,96 @@ | |||
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 | ||
15 | |||
16 | #include <asm/proc-fns.h> | ||
17 | |||
18 | #if __LINUX_ARM_ARCH__ >= 6 | ||
19 | |||
20 | /* | ||
21 | * On ARMv6, we have the following structure in the Context ID: | ||
22 | * | ||
23 | * 31 7 0 | ||
24 | * +-------------------------+-----------+ | ||
25 | * | process ID | ASID | | ||
26 | * +-------------------------+-----------+ | ||
27 | * | context ID | | ||
28 | * +-------------------------------------+ | ||
29 | * | ||
30 | * The ASID is used to tag entries in the CPU caches and TLBs. | ||
31 | * The context ID is used by debuggers and trace logic, and | ||
32 | * should be unique within all running processes. | ||
33 | */ | ||
34 | #define ASID_BITS 8 | ||
35 | #define ASID_MASK ((~0) << ASID_BITS) | ||
36 | |||
37 | extern unsigned int cpu_last_asid; | ||
38 | |||
39 | void __init_new_context(struct task_struct *tsk, struct mm_struct *mm); | ||
40 | void __new_context(struct mm_struct *mm); | ||
41 | |||
42 | static inline void check_context(struct mm_struct *mm) | ||
43 | { | ||
44 | if (unlikely((mm->context.id ^ cpu_last_asid) >> ASID_BITS)) | ||
45 | __new_context(mm); | ||
46 | } | ||
47 | |||
48 | #define init_new_context(tsk,mm) (__init_new_context(tsk,mm),0) | ||
49 | |||
50 | #else | ||
51 | |||
52 | #define check_context(mm) do { } while (0) | ||
53 | #define init_new_context(tsk,mm) 0 | ||
54 | |||
55 | #endif | ||
56 | |||
57 | #define destroy_context(mm) do { } while(0) | ||
58 | |||
59 | /* | ||
60 | * This is called when "tsk" is about to enter lazy TLB mode. | ||
61 | * | ||
62 | * mm: describes the currently active mm context | ||
63 | * tsk: task which is entering lazy tlb | ||
64 | * cpu: cpu number which is entering lazy tlb | ||
65 | * | ||
66 | * tsk->mm will be NULL | ||
67 | */ | ||
68 | static inline void | ||
69 | enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk) | ||
70 | { | ||
71 | } | ||
72 | |||
73 | /* | ||
74 | * This is the actual mm switch as far as the scheduler | ||
75 | * is concerned. No registers are touched. We avoid | ||
76 | * calling the CPU specific function when the mm hasn't | ||
77 | * actually changed. | ||
78 | */ | ||
79 | static inline void | ||
80 | switch_mm(struct mm_struct *prev, struct mm_struct *next, | ||
81 | struct task_struct *tsk) | ||
82 | { | ||
83 | unsigned int cpu = smp_processor_id(); | ||
84 | |||
85 | if (prev != next) { | ||
86 | cpu_set(cpu, next->cpu_vm_mask); | ||
87 | check_context(next); | ||
88 | cpu_switch_mm(next->pgd, next); | ||
89 | cpu_clear(cpu, prev->cpu_vm_mask); | ||
90 | } | ||
91 | } | ||
92 | |||
93 | #define deactivate_mm(tsk,mm) do { } while (0) | ||
94 | #define activate_mm(prev,next) switch_mm(prev, next, NULL) | ||
95 | |||
96 | #endif | ||