Add cpuset, an api for thread to cpu binding and cpu resource grouping

and assignment.
 - Add a reference to a struct cpuset in each thread that is inherited from
   the thread that created it.
 - Release the reference when the thread is destroyed.
 - Add prototypes for syscalls and macros for manipulating cpusets in
   sys/cpuset.h
 - Add syscalls to create, get, and set new numbered cpusets:
   cpuset(), cpuset_{get,set}id()
 - Add syscalls for getting and setting affinity masks for cpusets or
   individual threads: cpuid_{get,set}affinity()
 - Add types for the 'level' and 'which' parameters for the cpuset.  This
   will permit expansion of the api to cover cpu masks for other objects
   identifiable with an id_t integer.  For example, IRQs and Jails may be
   coming soon.
 - The root set 0 contains all valid cpus.  All thread initially belong to
   cpuset 1.  This permits migrating all threads off of certain cpus to
   reserve them for special applications.

Sponsored by:	Nokia
Discussed with:	arch, rwatson, brooks, davidxu, deischen
Reviewed by:	antoine

1 files changed, 907 insertions, 0 deletions

diff --git a/sys/kern/kern_cpuset.c b/sys/kern/kern_cpuset.c
new file mode 100644
index 0000000..b262dc1
--- /dev/null
+++ b/sys/kern/kern_cpuset.c
@@ -0,0 +1,907 @@
+/*-
+ * Copyright (c) 2008,  Jeffrey Roberson <jeff@freebsd.org>
+ * All rights reserved.
+ *
+ * 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 unmodified, 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 ``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 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.
+ *
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/sysproto.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/mutex.h>
+#include <sys/priv.h>
+#include <sys/proc.h>
+#include <sys/refcount.h>
+#include <sys/sched.h>
+#include <sys/smp.h>
+#include <sys/syscallsubr.h>
+#include <sys/cpuset.h>
+#include <sys/sx.h>
+#include <sys/refcount.h>
+#include <sys/queue.h>
+#include <sys/limits.h>
+
+#include <vm/uma.h>
+
+/*
+ * cpusets provide a mechanism for creating and manipulating sets of
+ * processors for the purpose of constraining the scheduling of threads to
+ * specific processors.
+ *
+ * Each process belongs to an identified set, by default this is set 1.  Each
+ * thread may further restrict the cpus it may run on to a subset of this
+ * named set.  This creates an anonymous set which other threads and processes
+ * may not join by number.
+ *
+ * The named set is referred to herein as the 'base' set to avoid ambiguity.
+ * This set is usually a child of a 'root' set while the anonymous set may
+ * simply be referred to as a mask.  In the syscall api these are referred to
+ * as the ROOT, CPUSET, and MASK levels where CPUSET is called 'base' here.
+ *
+ * Threads inherit their set from their creator whether it be anonymous or
+ * not.  This means that anonymous sets are immutable because they may be
+ * shared.  To modify an anonymous set a new set is created with the desired
+ * mask and the same parent as the existing anonymous set.  This gives the
+ * illusion of each thread having a private mask.A
+ *
+ * Via the syscall apis a user may ask to retrieve or modify the root, base,
+ * or mask that is discovered via a pid, tid, or setid.  Modifying a set
+ * modifies all numbered and anonymous child sets to comply with the new mask.
+ * Modifying a pid or tid's mask applies only to that tid but must still
+ * exist within the assigned parent set.
+ *
+ * A thread may not be assigned to a a group seperate from other threads in
+ * the process.  This is to remove ambiguity when the setid is queried with
+ * a pid argument.  There is no other technical limitation.
+ *
+ * This somewhat complex arrangement is intended to make it easy for
+ * applications to query available processors and bind their threads to
+ * specific processors while also allowing administrators to dynamically
+ * reprovision by changing sets which apply to groups of processes.
+ *
+ * A simple application should not concern itself with sets at all and
+ * rather apply masks to its own threads via CPU_WHICH_TID and a -1 id
+ * meaning 'curthread'.  It may query availble cpus for that tid with a
+ * getaffinity call using (CPU_LEVEL_CPUSET, CPU_WHICH_PID, -1, ...).
+ */
+static uma_zone_t cpuset_zone;
+static struct mtx cpuset_lock;
+static struct setlist cpuset_ids;
+struct cpuset *cpuset_zero;
+static struct unrhdr *cpuset_unr;
+
+/*
+ * Acquire a reference to a cpuset, all pointers must be tracked with refs.
+ */
+struct cpuset *
+cpuset_ref(struct cpuset *set)
+{
+
+	refcount_acquire(&set->cs_ref);
+	return (set);
+}
+
+/*
+ * Release a reference in a context where it is safe to allocte.
+ */
+void
+cpuset_rel(struct cpuset *set)
+{
+	cpusetid_t id;
+
+	if (refcount_release(&set->cs_ref) == 0)
+		return;
+	mtx_lock_spin(&cpuset_lock);
+	LIST_REMOVE(set, cs_siblings);
+	id = set->cs_id;
+	if (id != CPUSET_INVALID)
+		LIST_REMOVE(set, cs_link);
+	mtx_unlock_spin(&cpuset_lock);
+	cpuset_rel(set->cs_parent);
+	uma_zfree(cpuset_zone, set);
+	if (id != CPUSET_INVALID)
+		free_unr(cpuset_unr, id);
+}
+
+/*
+ * Deferred release must be used when in a context that is not safe to
+ * allocate/free.  This places any unreferenced sets on the list 'head'.
+ */
+static void
+cpuset_rel_defer(struct setlist *head, struct cpuset *set)
+{
+
+	if (refcount_release(&set->cs_ref) == 0)
+		return;
+	mtx_lock_spin(&cpuset_lock);
+	LIST_REMOVE(set, cs_siblings);
+	if (set->cs_id != CPUSET_INVALID)
+		LIST_REMOVE(set, cs_link);
+	LIST_INSERT_HEAD(head, set, cs_link);
+	mtx_unlock_spin(&cpuset_lock);
+}
+
+/*
+ * Complete a deferred release.  Removes the set from the list provided to
+ * cpuset_rel_defer.
+ */
+static void
+cpuset_rel_complete(struct cpuset *set)
+{
+	LIST_REMOVE(set, cs_link);
+	cpuset_rel(set->cs_parent);
+	uma_zfree(cpuset_zone, set);
+}
+
+/*
+ * Find a set based on an id.  Returns it with a ref.
+ */
+static struct cpuset *
+cpuset_lookup(cpusetid_t setid)
+{
+	struct cpuset *set;
+
+	if (setid == CPUSET_INVALID)
+		return (NULL);
+	mtx_lock_spin(&cpuset_lock);
+	LIST_FOREACH(set, &cpuset_ids, cs_link)
+		if (set->cs_id == setid)
+			break;
+	if (set)
+		cpuset_ref(set);
+	mtx_unlock_spin(&cpuset_lock);
+	return (set);
+}
+
+/*
+ * Create a set in the space provided in 'set' with the provided parameters.
+ * The set is returned with a single ref.  May return EDEADLK if the set
+ * will have no valid cpu based on restrictions from the parent.
+ */
+static int
+_cpuset_create(struct cpuset *set, struct cpuset *parent, cpuset_t *mask,
+    cpusetid_t id)
+{
+	int error;
+
+	error = 0;
+	CPU_COPY(mask, &set->cs_mask);
+	LIST_INIT(&set->cs_children);
+	refcount_init(&set->cs_ref, 1);
+	set->cs_flags = 0;
+	mtx_lock_spin(&cpuset_lock);
+	CPU_AND(mask, &parent->cs_mask);
+	if (!CPU_EMPTY(mask)) {
+		set->cs_id = id;
+		set->cs_parent = cpuset_ref(parent);
+		LIST_INSERT_HEAD(&parent->cs_children, set, cs_siblings);
+		if (set->cs_id != CPUSET_INVALID)
+			LIST_INSERT_HEAD(&cpuset_ids, set, cs_link);
+	} else
+		error = EDEADLK;
+	mtx_unlock_spin(&cpuset_lock);
+
+	return (error);
+}
+
+/*
+ * Create a new non-anonymous set with the requested parent and mask.  May
+ * return failures if the mask is invalid or a new number can not be
+ * allocated.
+ */
+static int
+cpuset_create(struct cpuset **setp, struct cpuset *parent, cpuset_t *mask)
+{
+	struct cpuset *set;
+	cpusetid_t id;
+	int error;
+
+	id = alloc_unr(cpuset_unr);
+	if (id == -1)
+		return (ENFILE);
+	*setp = set = uma_zalloc(cpuset_zone, M_WAITOK);
+	error = _cpuset_create(set, parent, mask, id);
+	if (error == 0)
+		return (0);
+	free_unr(cpuset_unr, id);
+	uma_zfree(cpuset_zone, set);
+
+	return (error);
+}
+
+/*
+ * Recursively check for errors that would occur from applying mask to
+ * the tree of sets starting at 'set'.  Checks for sets that would become
+ * empty as well as RDONLY flags.
+ */
+static int
+cpuset_testupdate(struct cpuset *set, cpuset_t *mask)
+{
+	struct cpuset *nset;
+	cpuset_t newmask;
+	int error;
+
+	mtx_assert(&cpuset_lock, MA_OWNED);
+	if (set->cs_flags & CPU_SET_RDONLY)
+		return (EPERM);
+	error = 0;
+	CPU_COPY(&set->cs_mask, &newmask);
+	CPU_AND(&newmask, mask);
+	if (CPU_EMPTY(&newmask))
+		return (EDEADLK);
+	LIST_FOREACH(nset, &set->cs_children, cs_siblings) 
+		if ((error = cpuset_testupdate(nset, &newmask)) != 0)
+			break;
+	return (error);
+}
+
+/*
+ * Applies the mask 'mask' without checking for empty sets or permissions.
+ */
+static void
+cpuset_update(struct cpuset *set, cpuset_t *mask)
+{
+	struct cpuset *nset;
+
+	mtx_assert(&cpuset_lock, MA_OWNED);
+	CPU_AND(&set->cs_mask, mask);
+	LIST_FOREACH(nset, &set->cs_children, cs_siblings) 
+		cpuset_update(nset, &set->cs_mask);
+
+	return;
+}
+
+/*
+ * Modify the set 'set' to use a copy of the mask provided.  Apply this new
+ * mask to restrict all children in the tree.  Checks for validity before
+ * applying the changes.
+ */
+static int
+cpuset_modify(struct cpuset *set, cpuset_t *mask)
+{
+	int error;
+
+	error = suser(curthread);
+	if (error)
+		return (error);
+	mtx_lock_spin(&cpuset_lock);
+	error = cpuset_testupdate(set, mask);
+	if (error)
+		goto out;
+	cpuset_update(set, mask);
+	CPU_COPY(mask, &set->cs_mask);
+out:
+	mtx_unlock_spin(&cpuset_lock);
+
+	return (error);
+}
+
+/*
+ * Walks up the tree from 'set' to find the root.  Returns the root
+ * referenced.
+ */
+static struct cpuset *
+cpuset_root(struct cpuset *set)
+{
+
+	mtx_lock_spin(&cpuset_lock);
+	for (; set->cs_parent != NULL; set = set->cs_parent)
+		if (set->cs_flags & CPU_SET_ROOT)
+			break;
+	cpuset_ref(set);
+	mtx_unlock_spin(&cpuset_lock);
+
+	return (set);
+}
+
+/*
+ * Find the first non-anonymous set starting from 'set'.  Returns this set
+ * referenced.  May return the passed in set with an extra ref if it is
+ * not anonymous. 
+ */
+static struct cpuset *
+cpuset_base(struct cpuset *set)
+{
+
+	mtx_lock_spin(&cpuset_lock);
+	if (set->cs_id == CPUSET_INVALID)
+		set = set->cs_parent;
+	cpuset_ref(set);
+	mtx_unlock_spin(&cpuset_lock);
+
+	return (set);
+}
+
+/*
+ * Resolve the 'which' parameter of several cpuset apis.
+ *
+ * For WHICH_PID and WHICH_TID return a locked proc and valid proc/tid.  Also
+ * checks for permission via p_cansched().
+ *
+ * For WHICH_SET returns a valid set with a new reference.
+ *
+ * -1 may be supplied for any argument to mean the current proc/thread or
+ * the base set of the current thread.  May fail with ESRCH/EPERM.
+ */
+static int
+cpuset_which(cpuwhich_t which, id_t id, struct proc **pp, struct thread **tdp,
+    struct cpuset **setp)
+{
+	struct cpuset *set;
+	struct thread *td;
+	struct proc *p;
+	int error;
+
+	*pp = p = NULL;
+	*tdp = td = NULL;
+	*setp = set = NULL;
+	switch (which) {
+	case CPU_WHICH_PID:
+		if (id == -1) {
+			PROC_LOCK(curproc);
+			p = curproc;
+			break;
+		}
+		if ((p = pfind(id)) == NULL)
+			return (ESRCH);
+		break;
+	case CPU_WHICH_TID:
+		if (id == -1) {
+			PROC_LOCK(curproc);
+			p = curproc;
+			td = curthread;
+			break;
+		}
+		sx_slock(&allproc_lock);
+		FOREACH_PROC_IN_SYSTEM(p) {
+			PROC_LOCK(p);
+			PROC_SLOCK(p);
+			FOREACH_THREAD_IN_PROC(p, td)
+				if (td->td_tid == id)
+					break;
+			PROC_SUNLOCK(p);
+			if (td != NULL)
+				break;
+			PROC_UNLOCK(p);
+		}
+		sx_sunlock(&allproc_lock);
+		if (td == NULL)
+			return (ESRCH);
+		break;
+	case CPU_WHICH_CPUSET:
+		if (id == -1) {
+			thread_lock(curthread);
+			set = cpuset_base(curthread->td_cpuset);
+			thread_unlock(curthread);
+		} else
+			set = cpuset_lookup(id);
+		if (set) {
+			*setp = set;
+			return (0);
+		}
+		return (ESRCH);
+	default:
+		return (EINVAL);
+	}
+	error = p_cansched(curthread, p);
+	if (error) {
+		PROC_UNLOCK(p);
+		return (error);
+	}
+	if (td == NULL)
+		td = FIRST_THREAD_IN_PROC(p);
+	*pp = p;
+	*tdp = td;
+	return (0);
+}
+
+/*
+ * Create an anonymous set with the provided mask in the space provided by
+ * 'fset'.  If the passed in set is anonymous we use its parent otherwise
+ * the new set is a child of 'set'.
+ */
+static int
+cpuset_shadow(struct cpuset *set, struct cpuset *fset, cpuset_t *mask)
+{
+	struct cpuset *parent;
+
+	if (set->cs_id == CPUSET_INVALID)
+		parent = set->cs_parent;
+	else
+		parent = set;
+	return (_cpuset_create(fset, parent, mask, CPUSET_INVALID));
+}
+
+/*
+ * Handle two cases for replacing the base set or mask of an entire process.
+ *
+ * 1) Set is non-null and mask is null.  This reparents all anonymous sets
+ *    to the provided set and replaces all non-anonymous td_cpusets with the
+ *    provided set.
+ * 2) Mask is non-null and set is null.  This replaces or creates anonymous
+ *    sets for every thread with the existing base as a parent.
+ *
+ * This is overly complicated because we can't allocate while holding a 
+ * spinlock and spinlocks must be held while changing and examining thread
+ * state.
+ */
+static int
+cpuset_setproc(pid_t pid, struct cpuset *set, cpuset_t *mask)
+{
+	struct setlist freelist;
+	struct setlist droplist;
+	struct cpuset *nset;
+	struct thread *td;
+	struct proc *p;
+	int threads;
+	int nfree;
+	int error;
+	/*
+	 * The algorithm requires two passes due to locking considerations.
+	 * 
+	 * 1) Lookup the process and acquire the locks in the required order.
+	 * 2) If enough cpusets have not been allocated release the locks and
+	 *    allocate them.  Loop.
+	 */
+	LIST_INIT(&freelist);
+	LIST_INIT(&droplist);
+	nfree = 0;
+	for (;;) {
+		error = cpuset_which(CPU_WHICH_PID, pid, &p, &td, &nset);
+		if (error)
+			goto out;
+		PROC_SLOCK(p);
+		if (nfree >= p->p_numthreads)
+			break;
+		threads = p->p_numthreads;
+		PROC_SUNLOCK(p);
+		PROC_UNLOCK(p);
+		for (; nfree < threads; nfree++) {
+			nset = uma_zalloc(cpuset_zone, M_WAITOK);
+			LIST_INSERT_HEAD(&freelist, nset, cs_link);
+		}
+	}
+	PROC_LOCK_ASSERT(p, MA_OWNED);
+	PROC_SLOCK_ASSERT(p, MA_OWNED);
+	/*
+	 * Now that the appropriate locks are held and we have enough cpusets,
+	 * replace each thread's cpuset while using deferred release.  We
+	 * must do this because the PROC_SLOCK has to be held while traversing
+	 * the thread list and this limits the type of operations allowed.
+	 */
+	error = 0;
+	FOREACH_THREAD_IN_PROC(p, td) {
+		struct cpuset *tdset;
+		thread_lock(td);
+		/*
+		 * If we presently have an anonymous set or are applying a
+		 * mask we must create an anonymous shadow set.  That is
+		 * either parented to our existing base or the supplied set.
+		 *
+		 * If we have a base set with no anonymous shadow we simply
+		 * replace it outright.
+		 */
+		tdset = td->td_cpuset;
+		if (tdset->cs_id == CPUSET_INVALID || mask) {
+			nset = LIST_FIRST(&freelist);
+			LIST_REMOVE(nset, cs_link);
+			if (mask)
+				error = cpuset_shadow(tdset, nset, mask);
+			else
+				error = _cpuset_create(nset, set,
+				    &tdset->cs_mask, CPUSET_INVALID);
+			if (error) {
+				LIST_INSERT_HEAD(&freelist, nset, cs_link);
+				thread_unlock(td);
+				break;
+			}
+		} else
+			nset = cpuset_ref(set);
+		cpuset_rel_defer(&droplist, tdset);
+		td->td_cpuset = nset;
+		sched_affinity(td);
+		thread_unlock(td);
+	}
+	PROC_SUNLOCK(p);
+	PROC_UNLOCK(p);
+out:
+	while ((nset = LIST_FIRST(&droplist)) != NULL)
+		cpuset_rel_complete(nset);
+	while ((nset = LIST_FIRST(&freelist)) != NULL) {
+		LIST_REMOVE(nset, cs_link);
+		uma_zfree(cpuset_zone, nset);
+	}
+	return (error);
+}
+
+/*
+ * Apply an anonymous mask to a single thread.
+ */
+static int
+cpuset_setthread(lwpid_t id, cpuset_t *mask)
+{
+	struct cpuset *nset;
+	struct cpuset *set;
+	struct thread *td;
+	struct proc *p;
+	int error;
+
+	nset = uma_zalloc(cpuset_zone, M_WAITOK);
+	error = cpuset_which(CPU_WHICH_TID, id, &p, &td, &nset);
+	if (error)
+		goto out;
+	thread_lock(td);
+	set = td->td_cpuset;
+	error = cpuset_shadow(set, nset, mask);
+	if (error == 0) {
+		cpuset_rel(td->td_cpuset);
+		td->td_cpuset = nset;
+		sched_affinity(td);
+		nset = NULL;
+	}
+	thread_unlock(td);
+	PROC_UNLOCK(p);
+out:
+	if (nset)
+		uma_zfree(cpuset_zone, nset);
+	return (error);
+}
+
+/*
+ * Creates the cpuset for thread0.  We make two sets:
+ * 
+ * 0 - The root set which should represent all valid processors in the
+ *     system.  It is initially created with a mask of all processors
+ *     because we don't know what processors are valid until cpuset_init()
+ *     runs.  This set is immutable.
+ * 1 - The default set which all processes are a member of until changed.
+ *     This allows an administrator to move all threads off of given cpus to
+ *     dedicate them to high priority tasks or save power etc.
+ */
+struct cpuset *
+cpuset_thread0(void)
+{
+	struct cpuset *set;
+	int error;
+
+	cpuset_zone = uma_zcreate("cpuset", sizeof(struct cpuset), NULL, NULL,
+	    NULL, NULL, UMA_ALIGN_PTR, 0);
+	mtx_init(&cpuset_lock, "cpuset", NULL, MTX_SPIN | MTX_RECURSE);
+	/*
+	 * Create the root system set for the whole machine.  Doesn't use
+	 * cpuset_create() due to NULL parent.
+	 */
+	set = uma_zalloc(cpuset_zone, M_WAITOK | M_ZERO);
+	set->cs_mask.__bits[0] = -1;
+	LIST_INIT(&set->cs_children);
+	LIST_INSERT_HEAD(&cpuset_ids, set, cs_link);
+	set->cs_ref = 1;
+	set->cs_flags = CPU_SET_ROOT;
+	cpuset_zero = set;
+	/*
+	 * Now derive a default, modifiable set from that to give out.
+	 */
+	set = uma_zalloc(cpuset_zone, M_WAITOK);
+	error = _cpuset_create(set, cpuset_zero, &cpuset_zero->cs_mask, 1);
+	KASSERT(error == 0, ("Error creating default set: %d\n", error));
+	/*
+	 * Initialize the unit allocator. 0 and 1 are allocated above.
+	 */
+	cpuset_unr = new_unrhdr(2, INT_MAX, NULL);
+
+	return (set);
+}
+
+/*
+ * This is called once the final set of system cpus is known.  Modifies
+ * the root set and all children and mark the root readonly.  
+ */
+static void
+cpuset_init(void *arg)
+{
+	cpuset_t mask;
+
+	CPU_ZERO(&mask);
+#ifdef SMP
+	mask.__bits[0] = all_cpus;
+#else
+	mask.__bits[0] = 1;
+#endif
+	if (cpuset_modify(cpuset_zero, &mask))
+		panic("Can't set initial cpuset mask.\n");
+	cpuset_zero->cs_flags |= CPU_SET_RDONLY;
+}
+SYSINIT(cpuset, SI_SUB_SMP, SI_ORDER_ANY, cpuset_init, NULL);
+
+#ifndef _SYS_SYSPROTO_H_
+struct cpuset_args {
+	cpusetid_t	*setid;
+};
+#endif
+int
+cpuset(struct thread *td, struct cpuset_args *uap)
+{
+	struct cpuset *root;
+	struct cpuset *set;
+	int error;
+
+	thread_lock(td);
+	root = cpuset_root(td->td_cpuset);
+	thread_unlock(td);
+	error = cpuset_create(&set, root, &root->cs_mask);
+	cpuset_rel(root);
+	if (error)
+		return (error);
+	error = cpuset_setproc(-1, set, NULL);
+	if (error == 0)
+		error = copyout(&set->cs_id, uap->setid, sizeof(set->cs_id));
+	cpuset_rel(set);
+	return (error);
+}
+
+#ifndef _SYS_SYSPROTO_H_
+struct cpuset_setid_args {
+	cpuwhich_t	which;
+	id_t		id;
+	cpusetid_t	setid;
+};
+#endif
+int
+cpuset_setid(struct thread *td, struct cpuset_setid_args *uap)
+{
+	struct cpuset *set;
+	int error;
+
+	/*
+	 * Presently we only support per-process sets.
+	 */
+	if (uap->which != CPU_WHICH_PID)
+		return (EINVAL);
+	set = cpuset_lookup(uap->setid);
+	if (set == NULL)
+		return (ESRCH);
+	error = cpuset_setproc(uap->id, set, NULL);
+	cpuset_rel(set);
+	return (error);
+}
+
+#ifndef _SYS_SYSPROTO_H_
+struct cpuset_getid_args {
+	cpulevel_t	level;
+	cpuwhich_t	which;
+	id_t		id;
+	cpusetid_t	*setid;
+#endif
+int
+cpuset_getid(struct thread *td, struct cpuset_getid_args *uap)
+{
+	struct cpuset *nset;
+	struct cpuset *set;
+	struct thread *ttd;
+	struct proc *p;
+	cpusetid_t id;
+	int error;
+
+	if (uap->level == CPU_LEVEL_WHICH && uap->which != CPU_WHICH_CPUSET)
+		return (EINVAL);
+	error = cpuset_which(uap->which, uap->id, &p, &ttd, &set);
+	if (error)
+		return (error);
+	switch (uap->which) {
+	case CPU_WHICH_TID:
+	case CPU_WHICH_PID:
+		thread_lock(ttd);
+		set = cpuset_base(ttd->td_cpuset);
+		thread_unlock(ttd);
+		PROC_UNLOCK(p);
+		break;
+	case CPU_WHICH_CPUSET:
+		break;
+	}
+	switch (uap->level) {
+	case CPU_LEVEL_ROOT:
+		nset = cpuset_root(set);
+		cpuset_rel(set);
+		set = nset;
+		break;
+	case CPU_LEVEL_CPUSET:
+		break;
+	case CPU_LEVEL_WHICH:
+		break;
+	}
+	id = set->cs_id;
+	cpuset_rel(set);
+	if (error == 0)
+		error = copyout(&id, uap->setid, sizeof(id));
+
+	return (error);
+}
+
+#ifndef _SYS_SYSPROTO_H_
+struct cpuset_getaffinity_args {
+        cpulevel_t	level;
+        cpuwhich_t	which;
+        int		id;
+        int		cpusetsize;
+        long 		*mask;
+};
+#endif
+int
+cpuset_getaffinity(struct thread *td, struct cpuset_getaffinity_args *uap)
+{
+	struct thread *ttd;
+	struct cpuset *nset;
+	struct cpuset *set;
+	struct proc *p;
+	cpuset_t *mask;
+	int error;
+	int size;
+
+	if (uap->cpusetsize < CPU_SETSIZE || uap->cpusetsize > CPU_MAXSIZE)
+		return (ERANGE);
+	size = uap->cpusetsize / NBBY;
+	mask = malloc(size, M_TEMP, M_WAITOK | M_ZERO);
+	error = cpuset_which(uap->which, uap->id, &p, &ttd, &set);
+	if (error)
+		goto out;
+	error = 0;
+	switch (uap->level) {
+	case CPU_LEVEL_ROOT:
+	case CPU_LEVEL_CPUSET:
+		switch (uap->which) {
+		case CPU_WHICH_TID:
+		case CPU_WHICH_PID:
+			thread_lock(ttd);
+			set = cpuset_ref(ttd->td_cpuset);
+			thread_unlock(ttd);
+			break;
+		case CPU_WHICH_CPUSET:
+			break;
+		}
+		if (uap->level == CPU_LEVEL_ROOT)
+			nset = cpuset_root(set);
+		else
+			nset = cpuset_base(set);
+		CPU_COPY(&nset->cs_mask, mask);
+		cpuset_rel(nset);
+		break;
+	case CPU_LEVEL_WHICH:
+		switch (uap->which) {
+		case CPU_WHICH_TID:
+			thread_lock(ttd);
+			CPU_COPY(&ttd->td_cpuset->cs_mask, mask);
+			thread_unlock(ttd);
+			break;
+		case CPU_WHICH_PID:
+			PROC_SLOCK(p);
+			FOREACH_THREAD_IN_PROC(p, ttd) {
+				thread_lock(ttd);
+				CPU_OR(mask, &ttd->td_cpuset->cs_mask);
+				thread_unlock(ttd);
+			}
+			PROC_SUNLOCK(p);
+			break;
+		case CPU_WHICH_CPUSET:
+			CPU_COPY(&set->cs_mask, mask);
+			break;
+		}
+		break;
+	default:
+		error = EINVAL;
+		break;
+	}
+	if (set)
+		cpuset_rel(set);
+	if (p)
+		PROC_UNLOCK(p);
+	if (error == 0)
+		error = copyout(mask, uap->mask, size);
+out:
+	free(mask, M_TEMP);
+	return (error);
+}
+
+#ifndef _SYS_SYSPROTO_H_
+struct cpuset_setaffinity_args {
+	cpulevel_t	level;
+        cpuwhich_t	which;
+        int		id;
+        int		cpusetsize;
+        long 	*	mask;
+};
+#endif
+int
+cpuset_setaffinity(struct thread *td, struct cpuset_setaffinity_args *uap)
+{
+	struct cpuset *nset;
+	struct cpuset *set;
+	struct thread *ttd;
+	struct proc *p;
+	cpuset_t *mask;
+	int error;
+
+	if (uap->cpusetsize < CPU_SETSIZE || uap->cpusetsize > CPU_MAXSIZE)
+		return (ERANGE);
+	mask = malloc(uap->cpusetsize / NBBY, M_TEMP, M_WAITOK | M_ZERO);
+	error = copyin(uap->mask, mask, uap->cpusetsize / NBBY);
+	if (error)
+		goto out;
+	switch (uap->level) {
+	case CPU_LEVEL_ROOT:
+	case CPU_LEVEL_CPUSET:
+		error = cpuset_which(uap->which, uap->id, &p, &ttd, &set);
+		if (error)
+			break;
+		switch (uap->which) {
+		case CPU_WHICH_TID:
+		case CPU_WHICH_PID:
+			thread_lock(ttd);
+			set = cpuset_ref(ttd->td_cpuset);
+			thread_unlock(ttd);
+			break;
+		case CPU_WHICH_CPUSET:
+			break;
+		}
+		if (uap->level == CPU_LEVEL_ROOT)
+			nset = cpuset_root(set);
+		else
+			nset = cpuset_base(set);
+		error = cpuset_modify(nset, mask);
+		cpuset_rel(nset);
+		cpuset_rel(set);
+		break;
+	case CPU_LEVEL_WHICH:
+		switch (uap->which) {
+		case CPU_WHICH_TID:
+			error = cpuset_setthread(uap->id, mask);
+			break;
+		case CPU_WHICH_PID:
+			error = cpuset_setproc(uap->id, NULL, mask);
+			break;
+		case CPU_WHICH_CPUSET:
+			error = cpuset_which(CPU_WHICH_CPUSET, uap->id, &p,
+			    &ttd, &set);
+			if (error == 0) {
+				error = cpuset_modify(set, mask);
+				cpuset_rel(set);
+			}
+			break;
+		default:
+			error = EINVAL;
+			break;
+		}
+		break;
+	default:
+		error = EINVAL;
+		break;
+	}
+out:
+	free(mask, M_TEMP);
+	return (error);
+}