projects/linux·blob v4.2 · refs

111 lines · 2.5 KiB

1/* See include/linux/lglock.h for description */
2#include <linux/module.h>
3#include <linux/lglock.h>
4#include <linux/cpu.h>
5#include <linux/string.h>
6
7/*
8 * Note there is no uninit, so lglocks cannot be defined in
9 * modules (but it's fine to use them from there)
10 * Could be added though, just undo lg_lock_init
11 */
12
13void lg_lock_init(struct lglock *lg, char *name)
14{
15 LOCKDEP_INIT_MAP(&lg->lock_dep_map, name, &lg->lock_key, 0);
16}
17EXPORT_SYMBOL(lg_lock_init);
18
19void lg_local_lock(struct lglock *lg)
20{
21 arch_spinlock_t *lock;
22
23 preempt_disable();
24 lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
25 lock = this_cpu_ptr(lg->lock);
26 arch_spin_lock(lock);
27}
28EXPORT_SYMBOL(lg_local_lock);
29
30void lg_local_unlock(struct lglock *lg)
31{
32 arch_spinlock_t *lock;
33
34 lock_release(&lg->lock_dep_map, 1, _RET_IP_);
35 lock = this_cpu_ptr(lg->lock);
36 arch_spin_unlock(lock);
37 preempt_enable();
38}
39EXPORT_SYMBOL(lg_local_unlock);
40
41void lg_local_lock_cpu(struct lglock *lg, int cpu)
42{
43 arch_spinlock_t *lock;
44
45 preempt_disable();
46 lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
47 lock = per_cpu_ptr(lg->lock, cpu);
48 arch_spin_lock(lock);
49}
50EXPORT_SYMBOL(lg_local_lock_cpu);
51
52void lg_local_unlock_cpu(struct lglock *lg, int cpu)
53{
54 arch_spinlock_t *lock;
55
56 lock_release(&lg->lock_dep_map, 1, _RET_IP_);
57 lock = per_cpu_ptr(lg->lock, cpu);
58 arch_spin_unlock(lock);
59 preempt_enable();
60}
61EXPORT_SYMBOL(lg_local_unlock_cpu);
62
63void lg_double_lock(struct lglock *lg, int cpu1, int cpu2)
64{
65 BUG_ON(cpu1 == cpu2);
66
67 /* lock in cpu order, just like lg_global_lock */
68 if (cpu2 < cpu1)
69 swap(cpu1, cpu2);
70
71 preempt_disable();
72 lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
73 arch_spin_lock(per_cpu_ptr(lg->lock, cpu1));
74 arch_spin_lock(per_cpu_ptr(lg->lock, cpu2));
75}
76
77void lg_double_unlock(struct lglock *lg, int cpu1, int cpu2)
78{
79 lock_release(&lg->lock_dep_map, 1, _RET_IP_);
80 arch_spin_unlock(per_cpu_ptr(lg->lock, cpu1));
81 arch_spin_unlock(per_cpu_ptr(lg->lock, cpu2));
82 preempt_enable();
83}
84
85void lg_global_lock(struct lglock *lg)
86{
87 int i;
88
89 preempt_disable();
90 lock_acquire_exclusive(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
91 for_each_possible_cpu(i) {
92 arch_spinlock_t *lock;
93 lock = per_cpu_ptr(lg->lock, i);
94 arch_spin_lock(lock);
95 }
96}
97EXPORT_SYMBOL(lg_global_lock);
98
99void lg_global_unlock(struct lglock *lg)
100{
101 int i;
102
103 lock_release(&lg->lock_dep_map, 1, _RET_IP_);
104 for_each_possible_cpu(i) {
105 arch_spinlock_t *lock;
106 lock = per_cpu_ptr(lg->lock, i);
107 arch_spin_unlock(lock);
108 }
109 preempt_enable();
110}
111EXPORT_SYMBOL(lg_global_unlock);