1 files changed, 79 insertions, 0 deletions
diff --git a/lib/libc/gen/sched_setaffinity.c b/lib/libc/gen/sched_setaffinity.c
new file mode 100644
index 000000000000..b878e1affc41
--- /dev/null
+++ b/lib/libc/gen/sched_setaffinity.c
@@ -0,0 +1,79 @@
+/*-
+ * Copyright (c) 2021 The FreeBSD Foundation
+ *
+ * This software were developed by Konstantin Belousov <kib@FreeBSD.org>
+ * under sponsorship from the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#define	_WANT_P_OSREL
+#include <sys/param.h>
+#include <sys/sysctl.h>
+#include <errno.h>
+#include <sched.h>
+#include <string.h>
+
+#include "libc_private.h"
+
+int
+sched_setaffinity(pid_t pid, size_t cpusetsz, const cpuset_t *cpuset)
+{
+	static int mp_maxid;
+	cpuwhich_t which;
+	cpuset_t c;
+	int error, lbs, cpu;
+	size_t len, sz;
+
+	if (__getosreldate() < P_OSREL_TIDPID) {
+		if (pid == 0 || pid > _PID_MAX)
+			which = CPU_WHICH_TID;
+		else
+			which = CPU_WHICH_PID;
+	} else
+		which = CPU_WHICH_TIDPID;
+
+	sz = cpusetsz > sizeof(cpuset_t) ? sizeof(cpuset_t) : cpusetsz;
+	memset(&c, 0, sizeof(c));
+	memcpy(&c, cpuset, sz);
+
+	/* Linux ignores high bits */
+	if (mp_maxid == 0) {
+		len = sizeof(mp_maxid);
+		error = sysctlbyname("kern.smp.maxid", &mp_maxid, &len,
+		    NULL, 0);
+		if (error == -1)
+			return (error);
+	}
+	lbs = CPU_FLS(&c) - 1;
+	if (lbs > mp_maxid) {
+		CPU_FOREACH_ISSET(cpu, &c)
+			if (cpu > mp_maxid)
+				CPU_CLR(cpu, &c);
+	}
+	error = cpuset_setaffinity(CPU_LEVEL_WHICH, which,
+	    pid == 0 ? -1 : pid, sizeof(cpuset_t), &c);
+	if (error == -1 && errno == EDEADLK)
+		errno = EINVAL;
+
+	return (error);
+}