usched: Allow process to change self cpu affinity
[dragonfly.git] / lib / libkinfo / kinfo_sched.c
bloba30c20c7b0075243cfff8199db44a0dd7e6b9aff
1 /*
2 * Copyright (c) 2004 The DragonFly Project. All rights reserved.
3 *
4 * This code is derived from software contributed to The DragonFly Project
5 * by Joerg Sonnenberger <joerg@bec.de>.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
16 * distribution.
17 * 3. Neither the name of The DragonFly Project nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
35 #include <sys/kinfo.h>
36 #include <sys/param.h>
37 #include <sys/sysctl.h>
39 #include <assert.h>
40 #include <stdlib.h>
41 #include <errno.h>
42 #include <kinfo.h>
44 int
45 kinfo_get_cpus(int *ncpus)
47 size_t len = sizeof(*ncpus);
49 return(sysctlbyname("hw.ncpu", ncpus, &len, NULL, 0));
52 int
53 kinfo_get_sched_cputime(struct kinfo_cputime *cputime)
55 struct kinfo_cputime *percpu = NULL;
56 size_t len = sizeof(struct kinfo_cputime) * SMP_MAXCPU;
57 int cpucount, error = 0;
59 _DIAGASSERT(cputime != NULL);
61 if ((percpu = malloc(len)) == NULL) {
62 error = ENOMEM;
63 goto done;
66 /* retrieve verbatim per-cpu statistics from kernel */
67 if (sysctlbyname("kern.cputime", percpu, &len, NULL, 0) < 0) {
68 error = errno;
69 goto done;
70 } else {
71 percpu = reallocf(percpu, len);
72 if (percpu == NULL) {
73 error = ENOMEM;
74 goto done;
78 /* aggregate per-cpu statistics retrieved from kernel */
79 cpucount = len / sizeof(struct kinfo_cputime);
80 cputime_pcpu_statistics(percpu, cputime, cpucount);
82 done:
83 if (percpu != NULL)
84 free(percpu);
85 return (error);
88 int
89 kinfo_get_sched_hz(int *hz)
91 struct kinfo_clockinfo clockinfo;
92 size_t len = sizeof(clockinfo);
93 int retval;
95 retval = sysctlbyname("kern.clockrate", &clockinfo, &len, NULL, 0);
96 if (retval)
97 return(retval);
99 *hz = clockinfo.ci_hz;
100 return(0);
104 kinfo_get_sched_stathz(int *stathz)
106 struct kinfo_clockinfo clockinfo;
107 size_t len = sizeof(clockinfo);
108 int retval;
110 retval = sysctlbyname("kern.clockrate", &clockinfo, &len, NULL, 0);
111 if (retval)
112 return(retval);
114 *stathz = clockinfo.ci_stathz;
115 return(0);
119 kinfo_get_sched_profhz(int *profhz)
121 struct kinfo_clockinfo clockinfo;
122 size_t len = sizeof(clockinfo);
123 int retval;
125 retval = sysctlbyname("kern.clockrate", &clockinfo, &len, NULL, 0);
126 if (retval)
127 return(retval);
129 *profhz = clockinfo.ci_profhz;
130 return(0);