1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
#include <litmus/fdso.h>
#ifdef CONFIG_LITMUS_LOCKING
#include <litmus/sched_plugin.h>
#include <litmus/trace.h>
static int create_generic_lock(void** obj_ref, obj_type_t type, void* __user arg);
static int open_generic_lock(struct od_table_entry* entry, void* __user arg);
static int close_generic_lock(struct od_table_entry* entry);
static void destroy_generic_lock(obj_type_t type, void* sem);
struct fdso_ops generic_lock_ops = {
.create = create_generic_lock,
.open = open_generic_lock,
.close = close_generic_lock,
.destroy = destroy_generic_lock
};
static inline bool is_lock(struct od_table_entry* entry)
{
return entry->class == &generic_lock_ops;
}
static inline struct litmus_lock* get_lock(struct od_table_entry* entry)
{
BUG_ON(!is_lock(entry));
return (struct litmus_lock*) entry->obj->obj;
}
static int create_generic_lock(void** obj_ref, obj_type_t type, void* __user arg)
{
struct litmus_lock* lock;
int err;
err = litmus->allocate_lock(&lock, type, arg);
if (err == 0)
*obj_ref = lock;
return err;
}
static int open_generic_lock(struct od_table_entry* entry, void* __user arg)
{
struct litmus_lock* lock = get_lock(entry);
if (lock->ops->open)
return lock->ops->open(lock, arg);
else
return 0; /* default: any task can open it */
}
static int close_generic_lock(struct od_table_entry* entry)
{
struct litmus_lock* lock = get_lock(entry);
if (lock->ops->close)
return lock->ops->close(lock);
else
return 0; /* default: closing succeeds */
}
static void destroy_generic_lock(obj_type_t type, void* obj)
{
struct litmus_lock* lock = (struct litmus_lock*) obj;
lock->ops->deallocate(lock);
}
asmlinkage long sys_litmus_lock(int lock_od)
{
long err = -EINVAL;
struct od_table_entry* entry;
struct litmus_lock* l;
TS_LOCK_START;
entry = get_entry_for_od(lock_od);
if (entry && is_lock(entry)) {
l = get_lock(entry);
TRACE_CUR("attempts to lock 0x%p\n", l);
err = l->ops->lock(l);
}
/* Note: task my have been suspended or preempted in between! Take
* this into account when computing overheads. */
TS_UNLOCK_END;
return err;
}
asmlinkage long sys_litmus_unlock(int lock_od)
{
long err = -EINVAL;
struct od_table_entry* entry;
struct litmus_lock* l;
TS_UNLOCK_START;
entry = get_entry_for_od(lock_od);
if (entry && is_lock(entry)) {
l = get_lock(entry);
TRACE_CUR("attempts to unlock 0x%p\n", l);
err = l->ops->unlock(l);
}
/* Note: task my have been preempted in between! Take this into
* account when computing overheads. */
TS_UNLOCK_END;
return err;
}
struct task_struct* waitqueue_first(wait_queue_head_t *wq)
{
wait_queue_t *q;
if (waitqueue_active(wq)) {
q = list_entry(wq->task_list.next,
wait_queue_t, task_list);
return (struct task_struct*) q->private;
} else
return NULL;
}
#else
struct fdso_ops generic_lock_ops = {};
asmlinkage long sys_litmus_lock(int sem_od)
{
return -ENOSYS;
}
asmlinkage long sys_litmus_unlock(int sem_od)
{
return -ENOSYS;
}
#endif
|
