xref: /netbsd-src/sys/kern/kern_softint.c (revision 0df165c04d0a9ca1adde9ed2b890344c937954a6)
1 /*	$NetBSD: kern_softint.c,v 1.4 2007/11/06 00:42:42 ad Exp $	*/
2 
3 /*-
4  * Copyright (c) 2007 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Doran.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by the NetBSD
21  *	Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Stub for code to be merged from the vmlocking CVS branch.
41  */
42 
43 #include <sys/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: kern_softint.c,v 1.4 2007/11/06 00:42:42 ad Exp $");
45 
46 #include <sys/param.h>
47 #include <sys/intr.h>
48 
49 u_int	softint_timing;
50 
51 /*
52  * softint_init:
53  *
54  *	Initialize per-CPU data structures.  Called from mi_cpu_attach().
55  */
56 void
57 softint_init(struct cpu_info *ci)
58 {
59 
60 	/* nothing yet */
61 }
62 
63 /*
64  * softint_establish:
65  *
66  *	Register a software interrupt handler.
67  */
68 void *
69 softint_establish(u_int flags, void (*func)(void *), void *arg)
70 {
71 	u_int level;
72 
73 	level = (flags & SOFTINT_LVLMASK);
74 	KASSERT(level < SOFTINT_COUNT);
75 
76 	switch (level) {
77 	case SOFTINT_CLOCK:
78 		level = IPL_SOFTCLOCK;
79 		break;
80 	case SOFTINT_NET:
81 	case SOFTINT_BIO:
82 		level = IPL_SOFTNET;
83 		break;
84 	case SOFTINT_SERIAL:
85 #ifdef IPL_SOFTSERIAL
86 		level = IPL_SOFTSERIAL;
87 #else
88 		level = IPL_SOFTNET;
89 #endif
90 		break;
91 	default:
92 		panic("softint_establish");
93 	}
94 
95 	return softintr_establish(level, func, arg);
96 }
97 
98 /*
99  * softint_disestablish:
100  *
101  *	Unregister a software interrupt handler.
102  */
103 void
104 softint_disestablish(void *arg)
105 {
106 
107 	softintr_disestablish(arg);
108 }
109 
110 /*
111  * softint_schedule:
112  *
113  *	Trigger a software interrupt.  Must be called from a hardware
114  *	interrupt handler, or with preemption disabled (since we are
115  *	using the value of curcpu()).
116  */
117 void
118 softint_schedule(void *arg)
119 {
120 
121 	softintr_schedule(arg);
122 }
123 
124 /*
125  * softint_block:
126  *
127  *	Update statistics when the soft interrupt blocks.
128  */
129 void
130 softint_block(lwp_t *l)
131 {
132 
133 	/* nothing yet */
134 }
135 
136 /*
137  * softint_picklwp:
138  *
139  *	Slow path: called from mi_switch() to pick the highest priority
140  *	soft interrupt LWP that needs to run.
141  */
142 lwp_t *
143 softint_picklwp(void)
144 {
145 
146 	panic("softint_picklwp");
147 }
148 
149 /*
150  * softint_overlay:
151  *
152  *	Slow path: called from lwp_userret() to run a soft interrupt
153  *	within the context of a user thread.  If the LWP blocks,
154  *	priority will be elevated in sched_kpri().
155  */
156 void
157 softint_overlay(void)
158 {
159 
160 	panic("softint_overlay");
161 }
162 
163 /*
164  * softint_kpri:
165  *
166  *	Adjust priority for a blocking user LWP that is handling a
167  *	soft interrupt.
168  */
169 pri_t
170 softint_kpri(lwp_t *l)
171 {
172 
173 	/* No point doing anything more fair / complicated. */
174 	return PRI_SOFTSERIAL;
175 }
176