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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Definitions used in MIPS MT SMTC "Interprocessor Interrupt" code.
3 */
4#ifndef __ASM_SMTC_IPI_H
5#define __ASM_SMTC_IPI_H
6
7#include <linux/spinlock.h>
8
9//#define SMTC_IPI_DEBUG
10
11#ifdef SMTC_IPI_DEBUG
12#include <asm/mipsregs.h>
13#include <asm/mipsmtregs.h>
14#endif /* SMTC_IPI_DEBUG */
15
16/*
17 * An IPI "message"
18 */
19
20struct smtc_ipi {
21 struct smtc_ipi *flink;
22 int type;
23 void *arg;
24 int dest;
25#ifdef SMTC_IPI_DEBUG
26 int sender;
27 long stamp;
28#endif /* SMTC_IPI_DEBUG */
29};
30
31/*
32 * Defined IPI Types
33 */
34
35#define LINUX_SMP_IPI 1
36#define SMTC_CLOCK_TICK 2
37#define IRQ_AFFINITY_IPI 3
38
39/*
40 * A queue of IPI messages
41 */
42
43struct smtc_ipi_q {
44 struct smtc_ipi *head;
45 spinlock_t lock;
46 struct smtc_ipi *tail;
47 int depth;
48 int resched_flag; /* reschedule already queued */
49};
50
51static inline void smtc_ipi_nq(struct smtc_ipi_q *q, struct smtc_ipi *p)
52{
53 unsigned long flags;
54
55 spin_lock_irqsave(&q->lock, flags);
56 if (q->head == NULL)
57 q->head = q->tail = p;
58 else
59 q->tail->flink = p;
60 p->flink = NULL;
61 q->tail = p;
62 q->depth++;
63#ifdef SMTC_IPI_DEBUG
64 p->sender = read_c0_tcbind();
65 p->stamp = read_c0_count();
66#endif /* SMTC_IPI_DEBUG */
67 spin_unlock_irqrestore(&q->lock, flags);
68}
69
70static inline struct smtc_ipi *__smtc_ipi_dq(struct smtc_ipi_q *q)
71{
72 struct smtc_ipi *p;
73
74 if (q->head == NULL)
75 p = NULL;
76 else {
77 p = q->head;
78 q->head = q->head->flink;
79 q->depth--;
80 /* Arguably unnecessary, but leaves queue cleaner */
81 if (q->head == NULL)
82 q->tail = NULL;
83 }
84
85 return p;
86}
87
88static inline struct smtc_ipi *smtc_ipi_dq(struct smtc_ipi_q *q)
89{
90 unsigned long flags;
91 struct smtc_ipi *p;
92
93 spin_lock_irqsave(&q->lock, flags);
94 p = __smtc_ipi_dq(q);
95 spin_unlock_irqrestore(&q->lock, flags);
96
97 return p;
98}
99
100static inline void smtc_ipi_req(struct smtc_ipi_q *q, struct smtc_ipi *p)
101{
102 unsigned long flags;
103
104 spin_lock_irqsave(&q->lock, flags);
105 if (q->head == NULL) {
106 q->head = q->tail = p;
107 p->flink = NULL;
108 } else {
109 p->flink = q->head;
110 q->head = p;
111 }
112 q->depth++;
113 spin_unlock_irqrestore(&q->lock, flags);
114}
115
116static inline int smtc_ipi_qdepth(struct smtc_ipi_q *q)
117{
118 unsigned long flags;
119 int retval;
120
121 spin_lock_irqsave(&q->lock, flags);
122 retval = q->depth;
123 spin_unlock_irqrestore(&q->lock, flags);
124 return retval;
125}
126
127extern void smtc_send_ipi(int cpu, int type, unsigned int action);
128
129#endif /* __ASM_SMTC_IPI_H */