blob: b4083ae348fb2c1e1c2614bed5c94cb5ac18c5b3 (
plain) (
blame)
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
|
// SPDX-License-Identifier: GPL-2.0
#include <config.h>
#include "preempt.h"
#include "assume.h"
#include "locks.h"
/* Support NR_CPUS of at most 64 */
#define CPU_PREEMPTION_LOCKS_INIT0 LOCK_IMPL_INITIALIZER
#define CPU_PREEMPTION_LOCKS_INIT1 \
CPU_PREEMPTION_LOCKS_INIT0, CPU_PREEMPTION_LOCKS_INIT0
#define CPU_PREEMPTION_LOCKS_INIT2 \
CPU_PREEMPTION_LOCKS_INIT1, CPU_PREEMPTION_LOCKS_INIT1
#define CPU_PREEMPTION_LOCKS_INIT3 \
CPU_PREEMPTION_LOCKS_INIT2, CPU_PREEMPTION_LOCKS_INIT2
#define CPU_PREEMPTION_LOCKS_INIT4 \
CPU_PREEMPTION_LOCKS_INIT3, CPU_PREEMPTION_LOCKS_INIT3
#define CPU_PREEMPTION_LOCKS_INIT5 \
CPU_PREEMPTION_LOCKS_INIT4, CPU_PREEMPTION_LOCKS_INIT4
/*
* Simulate disabling preemption by locking a particular cpu. NR_CPUS
* should be the actual number of cpus, not just the maximum.
*/
struct lock_impl cpu_preemption_locks[NR_CPUS] = {
CPU_PREEMPTION_LOCKS_INIT0
#if (NR_CPUS - 1) & 1
, CPU_PREEMPTION_LOCKS_INIT0
#endif
#if (NR_CPUS - 1) & 2
, CPU_PREEMPTION_LOCKS_INIT1
#endif
#if (NR_CPUS - 1) & 4
, CPU_PREEMPTION_LOCKS_INIT2
#endif
#if (NR_CPUS - 1) & 8
, CPU_PREEMPTION_LOCKS_INIT3
#endif
#if (NR_CPUS - 1) & 16
, CPU_PREEMPTION_LOCKS_INIT4
#endif
#if (NR_CPUS - 1) & 32
, CPU_PREEMPTION_LOCKS_INIT5
#endif
};
#undef CPU_PREEMPTION_LOCKS_INIT0
#undef CPU_PREEMPTION_LOCKS_INIT1
#undef CPU_PREEMPTION_LOCKS_INIT2
#undef CPU_PREEMPTION_LOCKS_INIT3
#undef CPU_PREEMPTION_LOCKS_INIT4
#undef CPU_PREEMPTION_LOCKS_INIT5
__thread int thread_cpu_id;
__thread int preempt_disable_count;
void preempt_disable(void)
{
BUG_ON(preempt_disable_count < 0 || preempt_disable_count == INT_MAX);
if (preempt_disable_count++)
return;
thread_cpu_id = nondet_int();
assume(thread_cpu_id >= 0);
assume(thread_cpu_id < NR_CPUS);
lock_impl_lock(&cpu_preemption_locks[thread_cpu_id]);
}
void preempt_enable(void)
{
BUG_ON(preempt_disable_count < 1);
if (--preempt_disable_count)
return;
lock_impl_unlock(&cpu_preemption_locks[thread_cpu_id]);
}
|
