xref: /netbsd-src/sys/rump/librump/rumpkern/threads.c (revision 3816d47b2c42fcd6e549e3407f842a5b1a1d23ad)
1 /*	$NetBSD: threads.c,v 1.6 2009/12/05 12:54:11 pooka Exp $	*/
2 
3 /*
4  * Copyright (c) 2007-2009 Antti Kantee.  All Rights Reserved.
5  *
6  * Development of this software was supported by
7  * The Finnish Cultural Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
19  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
24  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __KERNEL_RCSID(0, "$NetBSD: threads.c,v 1.6 2009/12/05 12:54:11 pooka Exp $");
33 
34 #include <sys/param.h>
35 #include <sys/kmem.h>
36 #include <sys/kthread.h>
37 #include <sys/systm.h>
38 
39 #include <machine/stdarg.h>
40 
41 #include <rump/rumpuser.h>
42 
43 #include "rump_private.h"
44 
45 struct kthdesc {
46 	void (*f)(void *);
47 	void *arg;
48 	struct lwp *mylwp;
49 };
50 
51 static void *
52 threadbouncer(void *arg)
53 {
54 	struct kthdesc *k = arg;
55 	struct lwp *l = k->mylwp;
56 	void (*f)(void *);
57 	void *thrarg;
58 
59 	f = k->f;
60 	thrarg = k->arg;
61 	rumpuser_free(k);
62 
63 	/* schedule ourselves */
64 	rumpuser_set_curlwp(l);
65 	rump_schedule();
66 
67 	if ((curlwp->l_pflag & LP_MPSAFE) == 0)
68 		KERNEL_LOCK(1, NULL);
69 
70 	f(thrarg);
71 
72 	panic("unreachable, should kthread_exit()");
73 }
74 
75 int
76 kthread_create(pri_t pri, int flags, struct cpu_info *ci,
77 	void (*func)(void *), void *arg, lwp_t **newlp, const char *fmt, ...)
78 {
79 	char thrstore[MAXCOMLEN];
80 	const char *thrname = NULL;
81 	va_list ap;
82 	struct kthdesc *k;
83 	struct lwp *l;
84 	int rv;
85 
86 	thrstore[0] = '\0';
87 	if (fmt) {
88 		va_start(ap, fmt);
89 		vsnprintf(thrstore, sizeof(thrstore), fmt, ap);
90 		va_end(ap);
91 		thrname = thrstore;
92 	}
93 
94 	/*
95 	 * We don't want a module unload thread.
96 	 * (XXX: yes, this is a kludge too, and the kernel should
97 	 * have a more flexible method for configuring which threads
98 	 * we want).
99 	 */
100 	if (strcmp(thrstore, "modunload") == 0) {
101 		return 0;
102 	}
103 
104 	if (!rump_threads) {
105 		/* fake them */
106 		if (strcmp(thrstore, "vrele") == 0) {
107 			printf("rump warning: threads not enabled, not starting"
108 			   " vrele thread\n");
109 			return 0;
110 		} else if (strcmp(thrstore, "cachegc") == 0) {
111 			printf("rump warning: threads not enabled, not starting"
112 			   " namecache g/c thread\n");
113 			return 0;
114 		} else if (strcmp(thrstore, "nfssilly") == 0) {
115 			printf("rump warning: threads not enabled, not enabling"
116 			   " nfs silly rename\n");
117 			return 0;
118 		} else if (strcmp(thrstore, "unpgc") == 0) {
119 			printf("rump warning: threads not enabled, not enabling"
120 			   " UNP garbage collection\n");
121 			return 0;
122 		} else if (strncmp(thrstore, "xcall", sizeof("xcall")-1) == 0) {
123 			printf("rump warning: threads not enabled, CPU xcall"
124 			   " not functional\n");
125 			return 0;
126 		} else
127 			panic("threads not available, setenv RUMP_THREADS 1");
128 	}
129 	KASSERT(fmt != NULL);
130 
131 	k = rumpuser_malloc(sizeof(struct kthdesc), 0);
132 	k->f = func;
133 	k->arg = arg;
134 	k->mylwp = l = rump_lwp_alloc(0, rump_nextlid());
135 	if (flags & KTHREAD_MPSAFE)
136 		l->l_pflag |= LP_MPSAFE;
137 	if (flags & KTHREAD_INTR)
138 		l->l_pflag |= LP_INTR;
139 	if (ci) {
140 		l->l_pflag |= LP_BOUND;
141 		l->l_cpu = ci;
142 	}
143 	rv = rumpuser_thread_create(threadbouncer, k, thrname);
144 	if (rv)
145 		return rv;
146 
147 	if (newlp)
148 		*newlp = l;
149 	return 0;
150 }
151 
152 void
153 kthread_exit(int ecode)
154 {
155 
156 	if ((curlwp->l_pflag & LP_MPSAFE) == 0)
157 		KERNEL_UNLOCK_LAST(NULL);
158 	rump_lwp_release(curlwp);
159 	rump_unschedule();
160 	rumpuser_thread_exit();
161 }
162