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 #include <sys/param.h> 30 #include <sys/sysctl.h> 31 #include <errno.h> 32 #include <sched.h> 33 #include <string.h> 34 35 int 36 sched_setaffinity(pid_t pid, size_t cpusetsz, const cpuset_t *cpuset) 37 { 38 static int mp_maxid; 39 cpuset_t c; 40 int error, lbs, cpu; 41 size_t len, sz; 42 43 sz = cpusetsz > sizeof(cpuset_t) ? sizeof(cpuset_t) : cpusetsz; 44 memset(&c, 0, sizeof(c)); 45 memcpy(&c, cpuset, sz); 46 47 /* Linux ignores high bits */ 48 if (mp_maxid == 0) { 49 len = sizeof(mp_maxid); 50 error = sysctlbyname("kern.smp.maxid", &mp_maxid, &len, 51 NULL, 0); 52 if (error == -1) 53 return (error); 54 } 55 lbs = CPU_FLS(&c) - 1; 56 if (lbs > mp_maxid) { 57 CPU_FOREACH_ISSET(cpu, &c) 58 if (cpu > mp_maxid) 59 CPU_CLR(cpu, &c); 60 } 61 error = cpuset_setaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TIDPID, 62 pid == 0 ? -1 : pid, sizeof(cpuset_t), &c); 63 if (error == -1 && errno == EDEADLK) 64 errno = EINVAL; 65 66 return (error); 67 } 68