blob: b1d4332b5cf0f22e2bf6f2fabf6aadb0b41f1680 (
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
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
|
#ifndef LINUX_HARDIRQ_H
#define LINUX_HARDIRQ_H
#include <linux/preempt.h>
#include <linux/smp_lock.h>
#include <asm/hardirq.h>
#include <asm/system.h>
/*
* We put the hardirq and softirq counter into the preemption
* counter. The bitmask has the following meaning:
*
* - bits 0-7 are the preemption count (max preemption depth: 256)
* - bits 8-15 are the softirq count (max # of softirqs: 256)
*
* The hardirq count can be overridden per architecture, the default is:
*
* - bits 16-27 are the hardirq count (max # of hardirqs: 4096)
* - ( bit 28 is the PREEMPT_ACTIVE flag. )
*
* PREEMPT_MASK: 0x000000ff
* SOFTIRQ_MASK: 0x0000ff00
* HARDIRQ_MASK: 0x0fff0000
*/
#define PREEMPT_BITS 8
#define SOFTIRQ_BITS 8
#ifndef HARDIRQ_BITS
#define HARDIRQ_BITS 12
/*
* The hardirq mask has to be large enough to have space for potentially
* all IRQ sources in the system nesting on a single CPU.
*/
#if (1 << HARDIRQ_BITS) < NR_IRQS
# error HARDIRQ_BITS is too low!
#endif
#endif
#define PREEMPT_SHIFT 0
#define SOFTIRQ_SHIFT (PREEMPT_SHIFT + PREEMPT_BITS)
#define HARDIRQ_SHIFT (SOFTIRQ_SHIFT + SOFTIRQ_BITS)
#define __IRQ_MASK(x) ((1UL << (x))-1)
#define PREEMPT_MASK (__IRQ_MASK(PREEMPT_BITS) << PREEMPT_SHIFT)
#define SOFTIRQ_MASK (__IRQ_MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT)
#define HARDIRQ_MASK (__IRQ_MASK(HARDIRQ_BITS) << HARDIRQ_SHIFT)
#define PREEMPT_OFFSET (1UL << PREEMPT_SHIFT)
#define SOFTIRQ_OFFSET (1UL << SOFTIRQ_SHIFT)
#define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT)
#if PREEMPT_ACTIVE < (1 << (HARDIRQ_SHIFT + HARDIRQ_BITS))
#error PREEMPT_ACTIVE is too low!
#endif
#define hardirq_count() (preempt_count() & HARDIRQ_MASK)
#define softirq_count() (preempt_count() & SOFTIRQ_MASK)
#define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK))
/*
* Are we doing bottom half or hardware interrupt processing?
* Are we in a softirq context? Interrupt context?
*/
#define in_irq() (hardirq_count())
#define in_softirq() (softirq_count())
#define in_interrupt() (irq_count())
#if defined(CONFIG_PREEMPT) && !defined(CONFIG_PREEMPT_BKL)
# define in_atomic() ((preempt_count() & ~PREEMPT_ACTIVE) != kernel_locked())
#else
# define in_atomic() ((preempt_count() & ~PREEMPT_ACTIVE) != 0)
#endif
#ifdef CONFIG_PREEMPT
# define preemptible() (preempt_count() == 0 && !irqs_disabled())
# define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
#else
# define preemptible() 0
# define IRQ_EXIT_OFFSET HARDIRQ_OFFSET
#endif
#ifdef CONFIG_SMP
extern void synchronize_irq(unsigned int irq);
#else
# define synchronize_irq(irq) barrier()
#endif
struct task_struct;
#ifndef CONFIG_VIRT_CPU_ACCOUNTING
static inline void account_system_vtime(struct task_struct *tsk)
{
}
#endif
/*
* It is safe to do non-atomic ops on ->hardirq_context,
* because NMI handlers may not preempt and the ops are
* always balanced, so the interrupted value of ->hardirq_context
* will always be restored.
*/
#define irq_enter() \
do { \
account_system_vtime(current); \
add_preempt_count(HARDIRQ_OFFSET); \
trace_hardirq_enter(); \
} while (0)
/*
* Exit irq context without processing softirqs:
*/
#define __irq_exit() \
do { \
trace_hardirq_exit(); \
account_system_vtime(current); \
sub_preempt_count(HARDIRQ_OFFSET); \
} while (0)
/*
* Exit irq context and process softirqs if needed:
*/
extern void irq_exit(void);
#define nmi_enter() irq_enter()
#define nmi_exit() __irq_exit()
#endif /* LINUX_HARDIRQ_H */
|