xref: /dragonfly/sbin/usched/usched.c (revision f984587a)
1 /*
2  * Copyright (c) 2012 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com> and Thomas Nikolajsen
6  * <thomas.nikolajsen@mail.dk>
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
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
16  *    the documentation and/or other materials provided with the
17  *    distribution.
18  * 3. Neither the name of The DragonFly Project nor the names of its
19  *    contributors may be used to endorse or promote products derived
20  *    from this software without specific, prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
26  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/types.h>
37 #include <sys/usched.h>
38 #include <sys/cpumask.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <unistd.h>
42 #include <string.h>
43 
44 static void usage(void);
45 
46 int DebugOpt;
47 
48 int
49 main(int ac, char **av)
50 {
51 	int ch;
52 	int res;
53 	char *sched = NULL;
54 	char *cpustr = NULL;
55 	char *sched_cpustr = NULL;
56 	char *p = NULL;
57 	cpumask_t cpumask;
58 	int cpuid;
59 	pid_t pid = getpid();  /* See usched_set(2) - BUGS */
60 
61 	CPUMASK_ASSZERO(cpumask);
62 
63 	while ((ch = getopt(ac, av, "d")) != -1) {
64 		switch (ch) {
65 		case 'd':
66 			DebugOpt = 1;
67 			break;
68 		default:
69 			usage();
70 			/* NOTREACHED */
71 		}
72 	}
73 	ac -= optind;
74 	av += optind;
75 
76 	if (ac < 2) {
77 		usage();
78 		/* NOTREACHED */
79 	}
80 	sched_cpustr = strdup(av[0]);
81 	sched = strsep(&sched_cpustr, ":");
82 	if (strcmp(sched, "default") == 0)
83 		fprintf(stderr,
84 			"Ignoring scheduler == \"default\": "
85 			"not implemented\n");
86 	cpustr = strsep(&sched_cpustr, "");
87 	if (strlen(sched) == 0 && cpustr == NULL) {
88 		usage();
89 		/* NOTREACHED */
90 	}
91 
92 	/*
93 	 * XXX needs expanded support for > 64 cpus
94 	 */
95 	if (cpustr != NULL) {
96 		uint64_t v;
97 		int baseid;
98 		char *ptr = cpustr;
99 
100 		baseid = 0;
101 		for (;;) {
102 			if (baseid >= CPU_SETSIZE) {
103 				fprintf(stderr, "cpumask too large\n");
104 				usage();
105 			}
106 			v = (uint64_t)strtoull(ptr, &ptr, 0);
107 			for (cpuid = 0; cpuid < (int)sizeof(v) * 8; ++cpuid) {
108 				if (v & (1LU << cpuid))
109 					CPUMASK_ORBIT(cpumask, baseid + cpuid);
110 			}
111 			if (*ptr == 0)
112 				break;
113 			if (*ptr != ',') {
114 				fprintf(stderr, "cpumask format error\n");
115 				usage();
116 			}
117 			++ptr;
118 			baseid += (int)sizeof(v) * 8;
119 		}
120 	}
121 
122 	if (strlen(sched) != 0) {
123 		if (DebugOpt) {
124 			fprintf(stderr,
125 				"DEBUG: USCHED_SET_SCHEDULER: scheduler: %s\n",
126 				sched);
127 		}
128 		res = usched_set(pid, USCHED_SET_SCHEDULER,
129 				 sched, strlen(sched));
130 		if (res != 0) {
131 			asprintf(&p,
132 				"usched_set(%d, USCHED_SET_SCHEDULER, "
133 				"\"%s\", %d)",
134 				pid, sched, (int)strlen(sched));
135 			perror(p);
136 			exit(1);
137 		}
138 	}
139 	if (CPUMASK_TESTNZERO(cpumask)) {
140 		for (cpuid = 0; cpuid < CPU_SETSIZE; ++cpuid) {
141 			if (CPUMASK_TESTBIT(cpumask, cpuid))
142 				break;
143 		}
144 		if (DebugOpt) {
145 			fprintf(stderr, "DEBUG: USCHED_SET_CPU: cpuid: %d\n",
146 				cpuid);
147 		}
148 		res = usched_set(pid, USCHED_SET_CPU, &cpuid, sizeof(int));
149 		if (res != 0) {
150 			asprintf(&p, "usched_set(%d, USCHED_SET_CPU, &%d, %d)",
151 				pid, cpuid, (int)sizeof(int));
152 			perror(p);
153 			exit(1);
154 		}
155 		CPUMASK_NANDBIT(cpumask, cpuid);
156 		while (CPUMASK_TESTNZERO(cpumask)) {
157 			++cpuid;
158 			if (CPUMASK_TESTBIT(cpumask, cpuid) == 0)
159 				continue;
160 			CPUMASK_NANDBIT(cpumask, cpuid);
161 			if (DebugOpt) {
162 				fprintf(stderr,
163 					"DEBUG: USCHED_ADD_CPU: cpuid: %d\n",
164 					cpuid);
165 			}
166 			res = usched_set(pid, USCHED_ADD_CPU,
167 					 &cpuid, sizeof(int));
168 			if (res != 0) {
169 				asprintf(&p,
170 					"usched_set(%d, USCHED_ADD_CPU, "
171 					"&%d, %d)",
172 					pid, cpuid, (int)sizeof(int));
173 				perror(p);
174 				exit(1);
175 			}
176 		}
177 	}
178 	execvp(av[1], av + 1);
179 	exit(1);
180 }
181 
182 static
183 void
184 usage(void)
185 {
186 	fprintf(stderr,
187 		"usage: usched [-d] {scheduler[:cpumask] | :cpumask} "
188 		"program [argument ...]\n");
189 	fprintf(stderr,
190 		"cpumask format: val[,val[,val[,val]]] in 64-bit chunks, "
191 		"lsb chunk first\n");
192 	exit(1);
193 }
194