1 /*-
2 * Copyright (c) 2021 The FreeBSD Foundation
3 *
4 * This software were developed by Konstantin Belousov <kib@FreeBSD.org>
5 * under sponsorship from the FreeBSD Foundation.
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:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #define _WANT_P_OSREL
30 #include <sys/param.h>
31 #include <sys/sysctl.h>
32 #include <errno.h>
33 #include <sched.h>
34 #include <string.h>
35
36 #include "libc_private.h"
37
38 int
sched_setaffinity(pid_t pid,size_t cpusetsz,const cpuset_t * cpuset)39 sched_setaffinity(pid_t pid, size_t cpusetsz, const cpuset_t *cpuset)
40 {
41 static int mp_maxid;
42 cpuwhich_t which;
43 cpuset_t c;
44 int error, lbs, cpu;
45 size_t len, sz;
46
47 if (__getosreldate() < P_OSREL_TIDPID) {
48 if (pid == 0 || pid > _PID_MAX)
49 which = CPU_WHICH_TID;
50 else
51 which = CPU_WHICH_PID;
52 } else
53 which = CPU_WHICH_TIDPID;
54
55 sz = cpusetsz > sizeof(cpuset_t) ? sizeof(cpuset_t) : cpusetsz;
56 memset(&c, 0, sizeof(c));
57 memcpy(&c, cpuset, sz);
58
59 /* Linux ignores high bits */
60 if (mp_maxid == 0) {
61 len = sizeof(mp_maxid);
62 error = sysctlbyname("kern.smp.maxid", &mp_maxid, &len,
63 NULL, 0);
64 if (error == -1)
65 return (error);
66 }
67 lbs = CPU_FLS(&c) - 1;
68 if (lbs > mp_maxid) {
69 CPU_FOREACH_ISSET(cpu, &c)
70 if (cpu > mp_maxid)
71 CPU_CLR(cpu, &c);
72 }
73 error = cpuset_setaffinity(CPU_LEVEL_WHICH, which,
74 pid == 0 ? -1 : pid, sizeof(cpuset_t), &c);
75 if (error == -1 && errno == EDEADLK)
76 errno = EINVAL;
77
78 return (error);
79 }
80