xref: /linux-6.15/include/linux/hardirq.h (revision a22b8f4b)
1 #ifndef LINUX_HARDIRQ_H
2 #define LINUX_HARDIRQ_H
3 
4 #include <linux/preempt_mask.h>
5 #include <linux/lockdep.h>
6 #include <linux/ftrace_irq.h>
7 #include <linux/vtime.h>
8 
9 
10 extern void synchronize_irq(unsigned int irq);
11 
12 #if defined(CONFIG_TINY_RCU)
13 
14 static inline void rcu_nmi_enter(void)
15 {
16 }
17 
18 static inline void rcu_nmi_exit(void)
19 {
20 }
21 
22 #else
23 extern void rcu_nmi_enter(void);
24 extern void rcu_nmi_exit(void);
25 #endif
26 
27 /*
28  * It is safe to do non-atomic ops on ->hardirq_context,
29  * because NMI handlers may not preempt and the ops are
30  * always balanced, so the interrupted value of ->hardirq_context
31  * will always be restored.
32  */
33 #define __irq_enter()					\
34 	do {						\
35 		account_irq_enter_time(current);	\
36 		add_preempt_count(HARDIRQ_OFFSET);	\
37 		trace_hardirq_enter();			\
38 	} while (0)
39 
40 /*
41  * Enter irq context (on NO_HZ, update jiffies):
42  */
43 extern void irq_enter(void);
44 
45 /*
46  * Exit irq context without processing softirqs:
47  */
48 #define __irq_exit()					\
49 	do {						\
50 		trace_hardirq_exit();			\
51 		account_irq_exit_time(current);		\
52 		sub_preempt_count(HARDIRQ_OFFSET);	\
53 	} while (0)
54 
55 /*
56  * Exit irq context and process softirqs if needed:
57  */
58 extern void irq_exit(void);
59 
60 #define nmi_enter()						\
61 	do {							\
62 		lockdep_off();					\
63 		ftrace_nmi_enter();				\
64 		BUG_ON(in_nmi());				\
65 		add_preempt_count(NMI_OFFSET + HARDIRQ_OFFSET);	\
66 		rcu_nmi_enter();				\
67 		trace_hardirq_enter();				\
68 	} while (0)
69 
70 #define nmi_exit()						\
71 	do {							\
72 		trace_hardirq_exit();				\
73 		rcu_nmi_exit();					\
74 		BUG_ON(!in_nmi());				\
75 		sub_preempt_count(NMI_OFFSET + HARDIRQ_OFFSET);	\
76 		ftrace_nmi_exit();				\
77 		lockdep_on();					\
78 	} while (0)
79 
80 #endif /* LINUX_HARDIRQ_H */
81