freebsd-skq/sys/kern/kern_cpuset.c
Kyle Evans f1b18a668d cpuset_set{affinity,domain}: do not allow empty masks
cpuset_modify() would not currently catch this, because it only checks that
the new mask is a subset of the root set and circumvents the EDEADLK check
in cpuset_testupdate().

This change both directly validates the mask coming in since we can
trivially detect an empty mask, and it updates cpuset_testupdate to catch
stuff like this going forward by always ensuring we don't end up with an
empty mask.

The check_mask argument has been renamed because the 'check' verbiage does
not imply to me that it's actually doing a different operation. We're either
augmenting the existing mask, or we are replacing it entirely.

Reported by:	syzbot+4e3b1009de98d2fabcda@syzkaller.appspotmail.com
Discussed with:	andrew
Reviewed by:	andrew, markj
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D27511
2020-12-08 18:47:22 +00:00

2427 lines
59 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2008, Jeffrey Roberson <jeff@freebsd.org>
* All rights reserved.
*
* Copyright (c) 2008 Nokia Corporation
* 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 "opt_ddb.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/ctype.h>
#include <sys/sysproto.h>
#include <sys/jail.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/capsicum.h>
#include <sys/cpuset.h>
#include <sys/domainset.h>
#include <sys/sx.h>
#include <sys/queue.h>
#include <sys/libkern.h>
#include <sys/limits.h>
#include <sys/bus.h>
#include <sys/interrupt.h>
#include <sys/vmmeter.h>
#include <vm/uma.h>
#include <vm/vm.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pageout.h>
#include <vm/vm_extern.h>
#include <vm/vm_param.h>
#include <vm/vm_phys.h>
#include <vm/vm_pagequeue.h>
#ifdef DDB
#include <ddb/ddb.h>
#endif /* DDB */
/*
* 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.
*
* 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 group separate 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 available cpus for that tid with a
* getaffinity call using (CPU_LEVEL_CPUSET, CPU_WHICH_PID, -1, ...).
*/
LIST_HEAD(domainlist, domainset);
struct domainset __read_mostly domainset_fixed[MAXMEMDOM];
struct domainset __read_mostly domainset_prefer[MAXMEMDOM];
struct domainset __read_mostly domainset_roundrobin;
static uma_zone_t cpuset_zone;
static uma_zone_t domainset_zone;
static struct mtx cpuset_lock;
static struct setlist cpuset_ids;
static struct domainlist cpuset_domains;
static struct unrhdr *cpuset_unr;
static struct cpuset *cpuset_zero, *cpuset_default, *cpuset_kernel;
static struct domainset domainset0, domainset2;
/* Return the size of cpuset_t at the kernel level */
SYSCTL_INT(_kern_sched, OID_AUTO, cpusetsize, CTLFLAG_RD | CTLFLAG_CAPRD,
SYSCTL_NULL_INT_PTR, sizeof(cpuset_t), "sizeof(cpuset_t)");
cpuset_t *cpuset_root;
cpuset_t cpuset_domain[MAXMEMDOM];
static int domainset_valid(const struct domainset *, const struct domainset *);
/*
* Find the first non-anonymous set starting from 'set'.
*/
static struct cpuset *
cpuset_getbase(struct cpuset *set)
{
if (set->cs_id == CPUSET_INVALID)
set = set->cs_parent;
return (set);
}
/*
* Walks up the tree from 'set' to find the root.
*/
static struct cpuset *
cpuset_getroot(struct cpuset *set)
{
while ((set->cs_flags & CPU_SET_ROOT) == 0 && set->cs_parent != NULL)
set = set->cs_parent;
return (set);
}
/*
* 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);
}
/*
* Walks up the tree from 'set' to find the root. Returns the root
* referenced.
*/
static struct cpuset *
cpuset_refroot(struct cpuset *set)
{
return (cpuset_ref(cpuset_getroot(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_refbase(struct cpuset *set)
{
return (cpuset_ref(cpuset_getbase(set)));
}
/*
* Release a reference in a context where it is safe to allocate.
*/
void
cpuset_rel(struct cpuset *set)
{
cpusetid_t id;
if (refcount_release_if_not_last(&set->cs_ref))
return;
mtx_lock_spin(&cpuset_lock);
if (!refcount_release(&set->cs_ref)) {
mtx_unlock_spin(&cpuset_lock);
return;
}
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_if_not_last(&set->cs_ref))
return;
mtx_lock_spin(&cpuset_lock);
if (!refcount_release(&set->cs_ref)) {
mtx_unlock_spin(&cpuset_lock);
return;
}
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)
{
cpusetid_t id;
id = set->cs_id;
LIST_REMOVE(set, cs_link);
cpuset_rel(set->cs_parent);
uma_zfree(cpuset_zone, set);
if (id != CPUSET_INVALID)
free_unr(cpuset_unr, id);
}
/*
* Find a set based on an id. Returns it with a ref.
*/
static struct cpuset *
cpuset_lookup(cpusetid_t setid, struct thread *td)
{
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);
KASSERT(td != NULL, ("[%s:%d] td is NULL", __func__, __LINE__));
if (set != NULL && jailed(td->td_ucred)) {
struct cpuset *jset, *tset;
jset = td->td_ucred->cr_prison->pr_cpuset;
for (tset = set; tset != NULL; tset = tset->cs_parent)
if (tset == jset)
break;
if (tset == NULL) {
cpuset_rel(set);
set = NULL;
}
}
return (set);
}
/*
* Initialize 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_init(struct cpuset *set, struct cpuset *parent,
const cpuset_t *mask, struct domainset *domain, cpusetid_t id)
{
if (domain == NULL)
domain = parent->cs_domain;
if (mask == NULL)
mask = &parent->cs_mask;
if (!CPU_OVERLAP(&parent->cs_mask, mask))
return (EDEADLK);
/* The domain must be prepared ahead of time. */
if (!domainset_valid(parent->cs_domain, domain))
return (EDEADLK);
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);
set->cs_domain = domain;
CPU_AND(&set->cs_mask, &parent->cs_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);
mtx_unlock_spin(&cpuset_lock);
return (0);
}
/*
* 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.
*
* If *setp is not NULL, then it will be used as-is. The caller must take
* into account that *setp will be inserted at the head of cpuset_ids and
* plan any potentially conflicting cs_link usage accordingly.
*/
static int
cpuset_create(struct cpuset **setp, struct cpuset *parent, const cpuset_t *mask)
{
struct cpuset *set;
cpusetid_t id;
int error;
bool dofree;
id = alloc_unr(cpuset_unr);
if (id == -1)
return (ENFILE);
dofree = (*setp == NULL);
if (*setp != NULL)
set = *setp;
else
*setp = set = uma_zalloc(cpuset_zone, M_WAITOK | M_ZERO);
error = cpuset_init(set, parent, mask, NULL, id);
if (error == 0)
return (0);
free_unr(cpuset_unr, id);
if (dofree)
uma_zfree(cpuset_zone, set);
return (error);
}
static void
cpuset_freelist_add(struct setlist *list, int count)
{
struct cpuset *set;
int i;
for (i = 0; i < count; i++) {
set = uma_zalloc(cpuset_zone, M_ZERO | M_WAITOK);
LIST_INSERT_HEAD(list, set, cs_link);
}
}
static void
cpuset_freelist_init(struct setlist *list, int count)
{
LIST_INIT(list);
cpuset_freelist_add(list, count);
}
static void
cpuset_freelist_free(struct setlist *list)
{
struct cpuset *set;
while ((set = LIST_FIRST(list)) != NULL) {
LIST_REMOVE(set, cs_link);
uma_zfree(cpuset_zone, set);
}
}
static void
domainset_freelist_add(struct domainlist *list, int count)
{
struct domainset *set;
int i;
for (i = 0; i < count; i++) {
set = uma_zalloc(domainset_zone, M_ZERO | M_WAITOK);
LIST_INSERT_HEAD(list, set, ds_link);
}
}
static void
domainset_freelist_init(struct domainlist *list, int count)
{
LIST_INIT(list);
domainset_freelist_add(list, count);
}
static void
domainset_freelist_free(struct domainlist *list)
{
struct domainset *set;
while ((set = LIST_FIRST(list)) != NULL) {
LIST_REMOVE(set, ds_link);
uma_zfree(domainset_zone, set);
}
}
/* Copy a domainset preserving mask and policy. */
static void
domainset_copy(const struct domainset *from, struct domainset *to)
{
DOMAINSET_COPY(&from->ds_mask, &to->ds_mask);
to->ds_policy = from->ds_policy;
to->ds_prefer = from->ds_prefer;
}
/* Return 1 if mask and policy are equal, otherwise 0. */
static int
domainset_equal(const struct domainset *one, const struct domainset *two)
{
return (DOMAINSET_CMP(&one->ds_mask, &two->ds_mask) == 0 &&
one->ds_policy == two->ds_policy &&
one->ds_prefer == two->ds_prefer);
}
/* Return 1 if child is a valid subset of parent. */
static int
domainset_valid(const struct domainset *parent, const struct domainset *child)
{
if (child->ds_policy != DOMAINSET_POLICY_PREFER)
return (DOMAINSET_SUBSET(&parent->ds_mask, &child->ds_mask));
return (DOMAINSET_ISSET(child->ds_prefer, &parent->ds_mask));
}
static int
domainset_restrict(const struct domainset *parent,
const struct domainset *child)
{
if (child->ds_policy != DOMAINSET_POLICY_PREFER)
return (DOMAINSET_OVERLAP(&parent->ds_mask, &child->ds_mask));
return (DOMAINSET_ISSET(child->ds_prefer, &parent->ds_mask));
}
/*
* Lookup or create a domainset. The key is provided in ds_mask and
* ds_policy. If the domainset does not yet exist the storage in
* 'domain' is used to insert. Otherwise this storage is freed to the
* domainset_zone and the existing domainset is returned.
*/
static struct domainset *
_domainset_create(struct domainset *domain, struct domainlist *freelist)
{
struct domainset *ndomain;
int i, j;
KASSERT(domain->ds_cnt <= vm_ndomains,
("invalid domain count in domainset %p", domain));
KASSERT(domain->ds_policy != DOMAINSET_POLICY_PREFER ||
domain->ds_prefer < vm_ndomains,
("invalid preferred domain in domains %p", domain));
mtx_lock_spin(&cpuset_lock);
LIST_FOREACH(ndomain, &cpuset_domains, ds_link)
if (domainset_equal(ndomain, domain))
break;
/*
* If the domain does not yet exist we insert it and initialize
* various iteration helpers which are not part of the key.
*/
if (ndomain == NULL) {
LIST_INSERT_HEAD(&cpuset_domains, domain, ds_link);
domain->ds_cnt = DOMAINSET_COUNT(&domain->ds_mask);
for (i = 0, j = 0; i < DOMAINSET_FLS(&domain->ds_mask); i++)
if (DOMAINSET_ISSET(i, &domain->ds_mask))
domain->ds_order[j++] = i;
}
mtx_unlock_spin(&cpuset_lock);
if (ndomain == NULL)
return (domain);
if (freelist != NULL)
LIST_INSERT_HEAD(freelist, domain, ds_link);
else
uma_zfree(domainset_zone, domain);
return (ndomain);
}
/*
* Are any of the domains in the mask empty? If so, silently
* remove them and update the domainset accordingly. If only empty
* domains are present, we must return failure.
*/
static bool
domainset_empty_vm(struct domainset *domain)
{
domainset_t empty;
int i, j;
DOMAINSET_ZERO(&empty);
for (i = 0; i < vm_ndomains; i++)
if (VM_DOMAIN_EMPTY(i))
DOMAINSET_SET(i, &empty);
if (DOMAINSET_SUBSET(&empty, &domain->ds_mask))
return (true);
/* Remove empty domains from the set and recompute. */
DOMAINSET_ANDNOT(&domain->ds_mask, &empty);
domain->ds_cnt = DOMAINSET_COUNT(&domain->ds_mask);
for (i = j = 0; i < DOMAINSET_FLS(&domain->ds_mask); i++)
if (DOMAINSET_ISSET(i, &domain->ds_mask))
domain->ds_order[j++] = i;
/* Convert a PREFER policy referencing an empty domain to RR. */
if (domain->ds_policy == DOMAINSET_POLICY_PREFER &&
DOMAINSET_ISSET(domain->ds_prefer, &empty)) {
domain->ds_policy = DOMAINSET_POLICY_ROUNDROBIN;
domain->ds_prefer = -1;
}
return (false);
}
/*
* Create or lookup a domainset based on the key held in 'domain'.
*/
struct domainset *
domainset_create(const struct domainset *domain)
{
struct domainset *ndomain;
/*
* Validate the policy. It must specify a useable policy number with
* only valid domains. Preferred must include the preferred domain
* in the mask.
*/
if (domain->ds_policy <= DOMAINSET_POLICY_INVALID ||
domain->ds_policy > DOMAINSET_POLICY_MAX)
return (NULL);
if (domain->ds_policy == DOMAINSET_POLICY_PREFER &&
!DOMAINSET_ISSET(domain->ds_prefer, &domain->ds_mask))
return (NULL);
if (!DOMAINSET_SUBSET(&domainset0.ds_mask, &domain->ds_mask))
return (NULL);
ndomain = uma_zalloc(domainset_zone, M_WAITOK | M_ZERO);
domainset_copy(domain, ndomain);
return _domainset_create(ndomain, NULL);
}
/*
* Update thread domainset pointers.
*/
static void
domainset_notify(void)
{
struct thread *td;
struct proc *p;
sx_slock(&allproc_lock);
FOREACH_PROC_IN_SYSTEM(p) {
PROC_LOCK(p);
if (p->p_state == PRS_NEW) {
PROC_UNLOCK(p);
continue;
}
FOREACH_THREAD_IN_PROC(p, td) {
thread_lock(td);
td->td_domain.dr_policy = td->td_cpuset->cs_domain;
thread_unlock(td);
}
PROC_UNLOCK(p);
}
sx_sunlock(&allproc_lock);
kernel_object->domain.dr_policy = cpuset_kernel->cs_domain;
}
/*
* Create a new set that is a subset of a parent.
*/
static struct domainset *
domainset_shadow(const struct domainset *pdomain,
const struct domainset *domain, struct domainlist *freelist)
{
struct domainset *ndomain;
ndomain = LIST_FIRST(freelist);
LIST_REMOVE(ndomain, ds_link);
/*
* Initialize the key from the request.
*/
domainset_copy(domain, ndomain);
/*
* Restrict the key by the parent.
*/
DOMAINSET_AND(&ndomain->ds_mask, &pdomain->ds_mask);
return _domainset_create(ndomain, freelist);
}
/*
* 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, int augment_mask)
{
struct cpuset *nset;
cpuset_t newmask;
int error;
mtx_assert(&cpuset_lock, MA_OWNED);
if (set->cs_flags & CPU_SET_RDONLY)
return (EPERM);
if (augment_mask) {
CPU_COPY(&set->cs_mask, &newmask);
CPU_AND(&newmask, mask);
} else
CPU_COPY(mask, &newmask);
if (CPU_EMPTY(&newmask))
return (EDEADLK);
error = 0;
LIST_FOREACH(nset, &set->cs_children, cs_siblings)
if ((error = cpuset_testupdate(nset, &newmask, 1)) != 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)
{
struct cpuset *root;
int error;
error = priv_check(curthread, PRIV_SCHED_CPUSET);
if (error)
return (error);
/*
* In case we are called from within the jail
* we do not allow modifying the dedicated root
* cpuset of the jail but may still allow to
* change child sets.
*/
if (jailed(curthread->td_ucred) &&
set->cs_flags & CPU_SET_ROOT)
return (EPERM);
/*
* Verify that we have access to this set of
* cpus.
*/
root = cpuset_getroot(set);
mtx_lock_spin(&cpuset_lock);
if (root && !CPU_SUBSET(&root->cs_mask, mask)) {
error = EINVAL;
goto out;
}
error = cpuset_testupdate(set, mask, 0);
if (error)
goto out;
CPU_COPY(mask, &set->cs_mask);
cpuset_update(set, mask);
out:
mtx_unlock_spin(&cpuset_lock);
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_domain(struct cpuset *set, struct domainset *dset,
struct domainset *orig, int *count, int augment_mask __unused)
{
struct cpuset *nset;
struct domainset *domain;
struct domainset newset;
int error;
mtx_assert(&cpuset_lock, MA_OWNED);
if (set->cs_flags & CPU_SET_RDONLY)
return (EPERM);
domain = set->cs_domain;
domainset_copy(domain, &newset);
if (!domainset_equal(domain, orig)) {
if (!domainset_restrict(domain, dset))
return (EDEADLK);
DOMAINSET_AND(&newset.ds_mask, &dset->ds_mask);
/* Count the number of domains that are changing. */
(*count)++;
}
error = 0;
LIST_FOREACH(nset, &set->cs_children, cs_siblings)
if ((error = cpuset_testupdate_domain(nset, &newset, domain,
count, 1)) != 0)
break;
return (error);
}
/*
* Applies the mask 'mask' without checking for empty sets or permissions.
*/
static void
cpuset_update_domain(struct cpuset *set, struct domainset *domain,
struct domainset *orig, struct domainlist *domains)
{
struct cpuset *nset;
mtx_assert(&cpuset_lock, MA_OWNED);
/*
* If this domainset has changed from the parent we must calculate
* a new set. Otherwise it simply inherits from the parent. When
* we inherit from the parent we get a new mask and policy. If the
* set is modified from the parent we keep the policy and only
* update the mask.
*/
if (set->cs_domain != orig) {
orig = set->cs_domain;
set->cs_domain = domainset_shadow(domain, orig, domains);
} else
set->cs_domain = domain;
LIST_FOREACH(nset, &set->cs_children, cs_siblings)
cpuset_update_domain(nset, set->cs_domain, orig, domains);
return;
}
/*
* Modify the set 'set' to use a copy the domainset provided. Apply this new
* mask to restrict all children in the tree. Checks for validity before
* applying the changes.
*/
static int
cpuset_modify_domain(struct cpuset *set, struct domainset *domain)
{
struct domainlist domains;
struct domainset temp;
struct domainset *dset;
struct cpuset *root;
int ndomains, needed;
int error;
error = priv_check(curthread, PRIV_SCHED_CPUSET);
if (error)
return (error);
/*
* In case we are called from within the jail
* we do not allow modifying the dedicated root
* cpuset of the jail but may still allow to
* change child sets.
*/
if (jailed(curthread->td_ucred) &&
set->cs_flags & CPU_SET_ROOT)
return (EPERM);
domainset_freelist_init(&domains, 0);
domain = domainset_create(domain);
ndomains = 0;
mtx_lock_spin(&cpuset_lock);
for (;;) {
root = cpuset_getroot(set);
dset = root->cs_domain;
/*
* Verify that we have access to this set of domains.
*/
if (!domainset_valid(dset, domain)) {
error = EINVAL;
goto out;
}
/*
* If applying prefer we keep the current set as the fallback.
*/
if (domain->ds_policy == DOMAINSET_POLICY_PREFER)
DOMAINSET_COPY(&set->cs_domain->ds_mask,
&domain->ds_mask);
/*
* Determine whether we can apply this set of domains and
* how many new domain structures it will require.
*/
domainset_copy(domain, &temp);
needed = 0;
error = cpuset_testupdate_domain(set, &temp, set->cs_domain,
&needed, 0);
if (error)
goto out;
if (ndomains >= needed)
break;
/* Dropping the lock; we'll need to re-evaluate again. */
mtx_unlock_spin(&cpuset_lock);
domainset_freelist_add(&domains, needed - ndomains);
ndomains = needed;
mtx_lock_spin(&cpuset_lock);
}
dset = set->cs_domain;
cpuset_update_domain(set, domain, dset, &domains);
out:
mtx_unlock_spin(&cpuset_lock);
domainset_freelist_free(&domains);
if (error == 0)
domainset_notify();
return (error);
}
/*
* 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.
*/
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;
}
td = tdfind(id, -1);
if (td == NULL)
return (ESRCH);
p = td->td_proc;
break;
case CPU_WHICH_CPUSET:
if (id == -1) {
thread_lock(curthread);
set = cpuset_refbase(curthread->td_cpuset);
thread_unlock(curthread);
} else
set = cpuset_lookup(id, curthread);
if (set) {
*setp = set;
return (0);
}
return (ESRCH);
case CPU_WHICH_JAIL:
{
/* Find `set' for prison with given id. */
struct prison *pr;
sx_slock(&allprison_lock);
pr = prison_find_child(curthread->td_ucred->cr_prison, id);
sx_sunlock(&allprison_lock);
if (pr == NULL)
return (ESRCH);
cpuset_ref(pr->pr_cpuset);
*setp = pr->pr_cpuset;
mtx_unlock(&pr->pr_mtx);
return (0);
}
case CPU_WHICH_IRQ:
case CPU_WHICH_DOMAIN:
return (0);
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);
}
static int
cpuset_testshadow(struct cpuset *set, const cpuset_t *mask,
const struct domainset *domain)
{
struct cpuset *parent;
struct domainset *dset;
parent = cpuset_getbase(set);
/*
* If we are restricting a cpu mask it must be a subset of the
* parent or invalid CPUs have been specified.
*/
if (mask != NULL && !CPU_SUBSET(&parent->cs_mask, mask))
return (EINVAL);
/*
* If we are restricting a domain mask it must be a subset of the
* parent or invalid domains have been specified.
*/
dset = parent->cs_domain;
if (domain != NULL && !domainset_valid(dset, domain))
return (EINVAL);
return (0);
}
/*
* Create an anonymous set with the provided mask in the space provided by
* 'nset'. 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 **nsetp,
const cpuset_t *mask, const struct domainset *domain,
struct setlist *cpusets, struct domainlist *domains)
{
struct cpuset *parent;
struct cpuset *nset;
struct domainset *dset;
struct domainset *d;
int error;
error = cpuset_testshadow(set, mask, domain);
if (error)
return (error);
parent = cpuset_getbase(set);
dset = parent->cs_domain;
if (mask == NULL)
mask = &set->cs_mask;
if (domain != NULL)
d = domainset_shadow(dset, domain, domains);
else
d = set->cs_domain;
nset = LIST_FIRST(cpusets);
error = cpuset_init(nset, parent, mask, d, CPUSET_INVALID);
if (error == 0) {
LIST_REMOVE(nset, cs_link);
*nsetp = nset;
}
return (error);
}
static struct cpuset *
cpuset_update_thread(struct thread *td, struct cpuset *nset)
{
struct cpuset *tdset;
tdset = td->td_cpuset;
td->td_cpuset = nset;
td->td_domain.dr_policy = nset->cs_domain;
sched_affinity(td);
return (tdset);
}
static int
cpuset_setproc_test_maskthread(struct cpuset *tdset, cpuset_t *mask,
struct domainset *domain)
{
struct cpuset *parent;
parent = cpuset_getbase(tdset);
if (mask == NULL)
mask = &tdset->cs_mask;
if (domain == NULL)
domain = tdset->cs_domain;
return cpuset_testshadow(parent, mask, domain);
}
static int
cpuset_setproc_maskthread(struct cpuset *tdset, cpuset_t *mask,
struct domainset *domain, struct cpuset **nsetp,
struct setlist *freelist, struct domainlist *domainlist)
{
struct cpuset *parent;
parent = cpuset_getbase(tdset);
if (mask == NULL)
mask = &tdset->cs_mask;
if (domain == NULL)
domain = tdset->cs_domain;
return cpuset_shadow(parent, nsetp, mask, domain, freelist,
domainlist);
}
static int
cpuset_setproc_setthread_mask(struct cpuset *tdset, struct cpuset *set,
cpuset_t *mask, struct domainset *domain)
{
struct cpuset *parent;
parent = cpuset_getbase(tdset);
/*
* If the thread restricted its mask then apply that same
* restriction to the new set, otherwise take it wholesale.
*/
if (CPU_CMP(&tdset->cs_mask, &parent->cs_mask) != 0) {
CPU_COPY(&tdset->cs_mask, mask);
CPU_AND(mask, &set->cs_mask);
} else
CPU_COPY(&set->cs_mask, mask);
/*
* If the thread restricted the domain then we apply the
* restriction to the new set but retain the policy.
*/
if (tdset->cs_domain != parent->cs_domain) {
domainset_copy(tdset->cs_domain, domain);
DOMAINSET_AND(&domain->ds_mask, &set->cs_domain->ds_mask);
} else
domainset_copy(set->cs_domain, domain);
if (CPU_EMPTY(mask) || DOMAINSET_EMPTY(&domain->ds_mask))
return (EDEADLK);
return (0);
}
static int
cpuset_setproc_test_setthread(struct cpuset *tdset, struct cpuset *set)
{
struct domainset domain;
cpuset_t mask;
if (tdset->cs_id != CPUSET_INVALID)
return (0);
return cpuset_setproc_setthread_mask(tdset, set, &mask, &domain);
}
static int
cpuset_setproc_setthread(struct cpuset *tdset, struct cpuset *set,
struct cpuset **nsetp, struct setlist *freelist,
struct domainlist *domainlist)
{
struct domainset domain;
cpuset_t mask;
int error;
/*
* If we're replacing on a thread that has not constrained the
* original set we can simply accept the new set.
*/
if (tdset->cs_id != CPUSET_INVALID) {
*nsetp = cpuset_ref(set);
return (0);
}
error = cpuset_setproc_setthread_mask(tdset, set, &mask, &domain);
if (error)
return (error);
return cpuset_shadow(set, nsetp, &mask, &domain, freelist,
domainlist);
}
static int
cpuset_setproc_newbase(struct thread *td, struct cpuset *set,
struct cpuset *nroot, struct cpuset **nsetp,
struct setlist *cpusets, struct domainlist *domainlist)
{
struct domainset ndomain;
cpuset_t nmask;
struct cpuset *pbase;
int error;
pbase = cpuset_getbase(td->td_cpuset);
/* Copy process mask, then further apply the new root mask. */
CPU_COPY(&pbase->cs_mask, &nmask);
CPU_AND(&nmask, &nroot->cs_mask);
domainset_copy(pbase->cs_domain, &ndomain);
DOMAINSET_AND(&ndomain.ds_mask, &set->cs_domain->ds_mask);
/* Policy is too restrictive, will not work. */
if (CPU_EMPTY(&nmask) || DOMAINSET_EMPTY(&ndomain.ds_mask))
return (EDEADLK);
/*
* Remove pbase from the freelist in advance, it'll be pushed to
* cpuset_ids on success. We assume here that cpuset_create() will not
* touch pbase on failure, and we just enqueue it back to the freelist
* to remain in a consistent state.
*/
pbase = LIST_FIRST(cpusets);
LIST_REMOVE(pbase, cs_link);
error = cpuset_create(&pbase, set, &nmask);
if (error != 0) {
LIST_INSERT_HEAD(cpusets, pbase, cs_link);
return (error);
}
/* Duplicates some work from above... oh well. */
pbase->cs_domain = domainset_shadow(set->cs_domain, &ndomain,
domainlist);
*nsetp = pbase;
return (0);
}
/*
* Handle four cases for updating an entire process.
*
* 1) Set is non-null and the process is not rebasing onto a new root. This
* reparents all anonymous sets to the provided set and replaces all
* non-anonymous td_cpusets with the provided set.
* 2) Set is non-null and the process is rebasing onto a new root. This
* creates a new base set if the process previously had its own base set,
* then reparents all anonymous sets either to that set or the provided set
* if one was not created. Non-anonymous sets are similarly replaced.
* 3) Mask is non-null. This replaces or creates anonymous sets for every
* thread with the existing base as a parent.
* 4) domain is non-null. This creates anonymous sets for every thread
* and replaces the domain set.
*
* 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 domainset *domain, bool rebase)
{
struct setlist freelist;
struct setlist droplist;
struct domainlist domainlist;
struct cpuset *base, *nset, *nroot, *tdroot;
struct thread *td;
struct proc *p;
int needed;
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.
*/
cpuset_freelist_init(&freelist, 1);
domainset_freelist_init(&domainlist, 1);
nfree = 1;
LIST_INIT(&droplist);
nfree = 0;
base = set;
nroot = NULL;
if (set != NULL)
nroot = cpuset_getroot(set);
for (;;) {
error = cpuset_which(CPU_WHICH_PID, pid, &p, &td, &nset);
if (error)
goto out;
tdroot = cpuset_getroot(td->td_cpuset);
needed = p->p_numthreads;
if (set != NULL && rebase && tdroot != nroot)
needed++;
if (nfree >= needed)
break;
PROC_UNLOCK(p);
if (nfree < needed) {
cpuset_freelist_add(&freelist, needed - nfree);
domainset_freelist_add(&domainlist, needed - nfree);
nfree = needed;
}
}
PROC_LOCK_ASSERT(p, MA_OWNED);
/*
* If we're changing roots and the root set is what has been specified
* as the parent, then we'll check if the process was previously using
* the root set and, if it wasn't, create a new base with the process's
* mask applied to it.
*/
if (set != NULL && rebase && nroot != tdroot) {
cpusetid_t base_id, root_id;
root_id = td->td_ucred->cr_prison->pr_cpuset->cs_id;
base_id = cpuset_getbase(td->td_cpuset)->cs_id;
if (base_id != root_id) {
error = cpuset_setproc_newbase(td, set, nroot, &base,
&freelist, &domainlist);
if (error != 0)
goto unlock_out;
}
}
/*
* Now that the appropriate locks are held and we have enough cpusets,
* make sure the operation will succeed before applying changes. The
* proc lock prevents td_cpuset from changing between calls.
*/
error = 0;
FOREACH_THREAD_IN_PROC(p, td) {
thread_lock(td);
if (set != NULL)
error = cpuset_setproc_test_setthread(td->td_cpuset,
base);
else
error = cpuset_setproc_test_maskthread(td->td_cpuset,
mask, domain);
thread_unlock(td);
if (error)
goto unlock_out;
}
/*
* Replace each thread's cpuset while using deferred release. We
* must do this because the thread lock must be held while operating
* on the thread and this limits the type of operations allowed.
*/
FOREACH_THREAD_IN_PROC(p, td) {
thread_lock(td);
if (set != NULL)
error = cpuset_setproc_setthread(td->td_cpuset, base,
&nset, &freelist, &domainlist);
else
error = cpuset_setproc_maskthread(td->td_cpuset, mask,
domain, &nset, &freelist, &domainlist);
if (error) {
thread_unlock(td);
break;
}
cpuset_rel_defer(&droplist, cpuset_update_thread(td, nset));
thread_unlock(td);
}
unlock_out:
PROC_UNLOCK(p);
out:
if (base != NULL && base != set)
cpuset_rel(base);
while ((nset = LIST_FIRST(&droplist)) != NULL)
cpuset_rel_complete(nset);
cpuset_freelist_free(&freelist);
domainset_freelist_free(&domainlist);
return (error);
}
static int
bitset_strprint(char *buf, size_t bufsiz, const struct bitset *set, int setlen)
{
size_t bytes;
int i, once;
char *p;
once = 0;
p = buf;
for (i = 0; i < __bitset_words(setlen); i++) {
if (once != 0) {
if (bufsiz < 1)
return (0);
*p = ',';
p++;
bufsiz--;
} else
once = 1;
if (bufsiz < sizeof(__STRING(ULONG_MAX)))
return (0);
bytes = snprintf(p, bufsiz, "%lx", set->__bits[i]);
p += bytes;
bufsiz -= bytes;
}
return (p - buf);
}
static int
bitset_strscan(struct bitset *set, int setlen, const char *buf)
{
int i, ret;
const char *p;
BIT_ZERO(setlen, set);
p = buf;
for (i = 0; i < __bitset_words(setlen); i++) {
if (*p == ',') {
p++;
continue;
}
ret = sscanf(p, "%lx", &set->__bits[i]);
if (ret == 0 || ret == -1)
break;
while (isxdigit(*p))
p++;
}
return (p - buf);
}
/*
* Return a string representing a valid layout for a cpuset_t object.
* It expects an incoming buffer at least sized as CPUSETBUFSIZ.
*/
char *
cpusetobj_strprint(char *buf, const cpuset_t *set)
{
bitset_strprint(buf, CPUSETBUFSIZ, (const struct bitset *)set,
CPU_SETSIZE);
return (buf);
}
/*
* Build a valid cpuset_t object from a string representation.
* It expects an incoming buffer at least sized as CPUSETBUFSIZ.
*/
int
cpusetobj_strscan(cpuset_t *set, const char *buf)
{
char p;
if (strlen(buf) > CPUSETBUFSIZ - 1)
return (-1);
p = buf[bitset_strscan((struct bitset *)set, CPU_SETSIZE, buf)];
if (p != '\0')
return (-1);
return (0);
}
/*
* Handle a domainset specifier in the sysctl tree. A poiner to a pointer to
* a domainset is in arg1. If the user specifies a valid domainset the
* pointer is updated.
*
* Format is:
* hex mask word 0,hex mask word 1,...:decimal policy:decimal preferred
*/
int
sysctl_handle_domainset(SYSCTL_HANDLER_ARGS)
{
char buf[DOMAINSETBUFSIZ];
struct domainset *dset;
struct domainset key;
int policy, prefer, error;
char *p;
dset = *(struct domainset **)arg1;
error = 0;
if (dset != NULL) {
p = buf + bitset_strprint(buf, DOMAINSETBUFSIZ,
(const struct bitset *)&dset->ds_mask, DOMAINSET_SETSIZE);
sprintf(p, ":%d:%d", dset->ds_policy, dset->ds_prefer);
} else
sprintf(buf, "<NULL>");
error = sysctl_handle_string(oidp, buf, sizeof(buf), req);
if (error != 0 || req->newptr == NULL)
return (error);
/*
* Read in and validate the string.
*/
memset(&key, 0, sizeof(key));
p = &buf[bitset_strscan((struct bitset *)&key.ds_mask,
DOMAINSET_SETSIZE, buf)];
if (p == buf)
return (EINVAL);
if (sscanf(p, ":%d:%d", &policy, &prefer) != 2)
return (EINVAL);
key.ds_policy = policy;
key.ds_prefer = prefer;
/* Domainset_create() validates the policy.*/
dset = domainset_create(&key);
if (dset == NULL)
return (EINVAL);
*(struct domainset **)arg1 = dset;
return (error);
}
/*
* Apply an anonymous mask or a domain to a single thread.
*/
static int
_cpuset_setthread(lwpid_t id, cpuset_t *mask, struct domainset *domain)
{
struct setlist cpusets;
struct domainlist domainlist;
struct cpuset *nset;
struct cpuset *set;
struct thread *td;
struct proc *p;
int error;
cpuset_freelist_init(&cpusets, 1);
domainset_freelist_init(&domainlist, domain != NULL);
error = cpuset_which(CPU_WHICH_TID, id, &p, &td, &set);
if (error)
goto out;
set = NULL;
thread_lock(td);
error = cpuset_shadow(td->td_cpuset, &nset, mask, domain,
&cpusets, &domainlist);
if (error == 0)
set = cpuset_update_thread(td, nset);
thread_unlock(td);
PROC_UNLOCK(p);
if (set)
cpuset_rel(set);
out:
cpuset_freelist_free(&cpusets);
domainset_freelist_free(&domainlist);
return (error);
}
/*
* Apply an anonymous mask to a single thread.
*/
int
cpuset_setthread(lwpid_t id, cpuset_t *mask)
{
return _cpuset_setthread(id, mask, NULL);
}
/*
* Apply new cpumask to the ithread.
*/
int
cpuset_setithread(lwpid_t id, int cpu)
{
cpuset_t mask;
CPU_ZERO(&mask);
if (cpu == NOCPU)
CPU_COPY(cpuset_root, &mask);
else
CPU_SET(cpu, &mask);
return _cpuset_setthread(id, &mask, NULL);
}
/*
* Initialize static domainsets after NUMA information is available. This is
* called before memory allocators are initialized.
*/
void
domainset_init(void)
{
struct domainset *dset;
int i;
dset = &domainset_roundrobin;
DOMAINSET_COPY(&all_domains, &dset->ds_mask);
dset->ds_policy = DOMAINSET_POLICY_ROUNDROBIN;
dset->ds_prefer = -1;
_domainset_create(dset, NULL);
for (i = 0; i < vm_ndomains; i++) {
dset = &domainset_fixed[i];
DOMAINSET_ZERO(&dset->ds_mask);
DOMAINSET_SET(i, &dset->ds_mask);
dset->ds_policy = DOMAINSET_POLICY_ROUNDROBIN;
_domainset_create(dset, NULL);
dset = &domainset_prefer[i];
DOMAINSET_COPY(&all_domains, &dset->ds_mask);
dset->ds_policy = DOMAINSET_POLICY_PREFER;
dset->ds_prefer = i;
_domainset_create(dset, NULL);
}
}
/*
* Create the domainset for cpuset 0, 1 and cpuset 2.
*/
void
domainset_zero(void)
{
struct domainset *dset, *tmp;
mtx_init(&cpuset_lock, "cpuset", NULL, MTX_SPIN | MTX_RECURSE);
dset = &domainset0;
DOMAINSET_COPY(&all_domains, &dset->ds_mask);
dset->ds_policy = DOMAINSET_POLICY_FIRSTTOUCH;
dset->ds_prefer = -1;
curthread->td_domain.dr_policy = _domainset_create(dset, NULL);
domainset_copy(dset, &domainset2);
domainset2.ds_policy = DOMAINSET_POLICY_INTERLEAVE;
kernel_object->domain.dr_policy = _domainset_create(&domainset2, NULL);
/* Remove empty domains from the global policies. */
LIST_FOREACH_SAFE(dset, &cpuset_domains, ds_link, tmp)
if (domainset_empty_vm(dset))
LIST_REMOVE(dset, ds_link);
}
/*
* Creates system-wide cpusets and the cpuset for thread0 including three
* sets:
*
* 0 - The root set which should represent all valid processors in the
* system. 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.
* 2 - The kernel set which allows restriction and policy to be applied only
* to kernel threads and the kernel_object.
*/
struct cpuset *
cpuset_thread0(void)
{
struct cpuset *set;
int i;
int error __unused;
cpuset_zone = uma_zcreate("cpuset", sizeof(struct cpuset), NULL, NULL,
NULL, NULL, UMA_ALIGN_CACHE, 0);
domainset_zone = uma_zcreate("domainset", sizeof(struct domainset),
NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
/*
* Create the root system set (0) for the whole machine. Doesn't use
* cpuset_create() due to NULL parent.
*/
set = uma_zalloc(cpuset_zone, M_WAITOK | M_ZERO);
CPU_COPY(&all_cpus, &set->cs_mask);
LIST_INIT(&set->cs_children);
LIST_INSERT_HEAD(&cpuset_ids, set, cs_link);
refcount_init(&set->cs_ref, 1);
set->cs_flags = CPU_SET_ROOT | CPU_SET_RDONLY;
set->cs_domain = &domainset0;
cpuset_zero = set;
cpuset_root = &set->cs_mask;
/*
* Now derive a default (1), modifiable set from that to give out.
*/
set = uma_zalloc(cpuset_zone, M_WAITOK | M_ZERO);
error = cpuset_init(set, cpuset_zero, NULL, NULL, 1);
KASSERT(error == 0, ("Error creating default set: %d\n", error));
cpuset_default = set;
/*
* Create the kernel set (2).
*/
set = uma_zalloc(cpuset_zone, M_WAITOK | M_ZERO);
error = cpuset_init(set, cpuset_zero, NULL, NULL, 2);
KASSERT(error == 0, ("Error creating kernel set: %d\n", error));
set->cs_domain = &domainset2;
cpuset_kernel = set;
/*
* Initialize the unit allocator. 0 and 1 are allocated above.
*/
cpuset_unr = new_unrhdr(3, INT_MAX, NULL);
/*
* If MD code has not initialized per-domain cpusets, place all
* CPUs in domain 0.
*/
for (i = 0; i < MAXMEMDOM; i++)
if (!CPU_EMPTY(&cpuset_domain[i]))
goto domains_set;
CPU_COPY(&all_cpus, &cpuset_domain[0]);
domains_set:
return (cpuset_default);
}
void
cpuset_kernthread(struct thread *td)
{
struct cpuset *set;
thread_lock(td);
set = td->td_cpuset;
td->td_cpuset = cpuset_ref(cpuset_kernel);
thread_unlock(td);
cpuset_rel(set);
}
/*
* Create a cpuset, which would be cpuset_create() but
* mark the new 'set' as root.
*
* We are not going to reparent the td to it. Use cpuset_setproc_update_set()
* for that.
*
* In case of no error, returns the set in *setp locked with a reference.
*/
int
cpuset_create_root(struct prison *pr, struct cpuset **setp)
{
struct cpuset *set;
int error;
KASSERT(pr != NULL, ("[%s:%d] invalid pr", __func__, __LINE__));
KASSERT(setp != NULL, ("[%s:%d] invalid setp", __func__, __LINE__));
set = NULL;
error = cpuset_create(&set, pr->pr_cpuset, &pr->pr_cpuset->cs_mask);
if (error)
return (error);
KASSERT(set != NULL, ("[%s:%d] cpuset_create returned invalid data",
__func__, __LINE__));
/* Mark the set as root. */
set->cs_flags |= CPU_SET_ROOT;
*setp = set;
return (0);
}
int
cpuset_setproc_update_set(struct proc *p, struct cpuset *set)
{
int error;
KASSERT(p != NULL, ("[%s:%d] invalid proc", __func__, __LINE__));
KASSERT(set != NULL, ("[%s:%d] invalid set", __func__, __LINE__));
cpuset_ref(set);
error = cpuset_setproc(p->p_pid, set, NULL, NULL, true);
if (error)
return (error);
cpuset_rel(set);
return (0);
}
/*
* In Capability mode, the only accesses that are permitted are to the current
* thread and process' CPU and domain sets.
*/
static int
cpuset_check_capabilities(struct thread *td, cpulevel_t level, cpuwhich_t which,
id_t id)
{
if (IN_CAPABILITY_MODE(td)) {
if (level != CPU_LEVEL_WHICH)
return (ECAPMODE);
if (which != CPU_WHICH_TID && which != CPU_WHICH_PID)
return (ECAPMODE);
if (id != -1 &&
!(which == CPU_WHICH_TID && id == td->td_tid) &&
!(which == CPU_WHICH_PID && id == td->td_proc->p_pid))
return (ECAPMODE);
}
return (0);
}
#ifndef _SYS_SYSPROTO_H_
struct cpuset_args {
cpusetid_t *setid;
};
#endif
int
sys_cpuset(struct thread *td, struct cpuset_args *uap)
{
struct cpuset *root;
struct cpuset *set;
int error;
thread_lock(td);
root = cpuset_refroot(td->td_cpuset);
thread_unlock(td);
set = NULL;
error = cpuset_create(&set, root, &root->cs_mask);
cpuset_rel(root);
if (error)
return (error);
error = copyout(&set->cs_id, uap->setid, sizeof(set->cs_id));
if (error == 0)
error = cpuset_setproc(-1, set, NULL, NULL, false);
cpuset_rel(set);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct cpuset_setid_args {
cpuwhich_t which;
id_t id;
cpusetid_t setid;
};
#endif
int
sys_cpuset_setid(struct thread *td, struct cpuset_setid_args *uap)
{
return (kern_cpuset_setid(td, uap->which, uap->id, uap->setid));
}
int
kern_cpuset_setid(struct thread *td, cpuwhich_t which,
id_t id, cpusetid_t setid)
{
struct cpuset *set;
int error;
/*
* Presently we only support per-process sets.
*/
if (which != CPU_WHICH_PID)
return (EINVAL);
set = cpuset_lookup(setid, td);
if (set == NULL)
return (ESRCH);
error = cpuset_setproc(id, set, NULL, NULL, false);
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
sys_cpuset_getid(struct thread *td, struct cpuset_getid_args *uap)
{
return (kern_cpuset_getid(td, uap->level, uap->which, uap->id,
uap->setid));
}
int
kern_cpuset_getid(struct thread *td, cpulevel_t level, cpuwhich_t which,
id_t id, cpusetid_t *setid)
{
struct cpuset *nset;
struct cpuset *set;
struct thread *ttd;
struct proc *p;
cpusetid_t tmpid;
int error;
if (level == CPU_LEVEL_WHICH && which != CPU_WHICH_CPUSET)
return (EINVAL);
error = cpuset_which(which, id, &p, &ttd, &set);
if (error)
return (error);
switch (which) {
case CPU_WHICH_TID:
case CPU_WHICH_PID:
thread_lock(ttd);
set = cpuset_refbase(ttd->td_cpuset);
thread_unlock(ttd);
PROC_UNLOCK(p);
break;
case CPU_WHICH_CPUSET:
case CPU_WHICH_JAIL:
break;
case CPU_WHICH_IRQ:
case CPU_WHICH_DOMAIN:
return (EINVAL);
}
switch (level) {
case CPU_LEVEL_ROOT:
nset = cpuset_refroot(set);
cpuset_rel(set);
set = nset;
break;
case CPU_LEVEL_CPUSET:
break;
case CPU_LEVEL_WHICH:
break;
}
tmpid = set->cs_id;
cpuset_rel(set);
if (error == 0)
error = copyout(&tmpid, setid, sizeof(tmpid));
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct cpuset_getaffinity_args {
cpulevel_t level;
cpuwhich_t which;
id_t id;
size_t cpusetsize;
cpuset_t *mask;
};
#endif
int
sys_cpuset_getaffinity(struct thread *td, struct cpuset_getaffinity_args *uap)
{
return (kern_cpuset_getaffinity(td, uap->level, uap->which,
uap->id, uap->cpusetsize, uap->mask));
}
int
kern_cpuset_getaffinity(struct thread *td, cpulevel_t level, cpuwhich_t which,
id_t id, size_t cpusetsize, cpuset_t *maskp)
{
struct thread *ttd;
struct cpuset *nset;
struct cpuset *set;
struct proc *p;
cpuset_t *mask;
int error;
size_t size;
if (cpusetsize < sizeof(cpuset_t) || cpusetsize > CPU_MAXSIZE / NBBY)
return (ERANGE);
error = cpuset_check_capabilities(td, level, which, id);
if (error != 0)
return (error);
size = cpusetsize;
mask = malloc(size, M_TEMP, M_WAITOK | M_ZERO);
error = cpuset_which(which, id, &p, &ttd, &set);
if (error)
goto out;
switch (level) {
case CPU_LEVEL_ROOT:
case CPU_LEVEL_CPUSET:
switch (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:
case CPU_WHICH_JAIL:
break;
case CPU_WHICH_IRQ:
case CPU_WHICH_INTRHANDLER:
case CPU_WHICH_ITHREAD:
case CPU_WHICH_DOMAIN:
error = EINVAL;
goto out;
}
if (level == CPU_LEVEL_ROOT)
nset = cpuset_refroot(set);
else
nset = cpuset_refbase(set);
CPU_COPY(&nset->cs_mask, mask);
cpuset_rel(nset);
break;
case CPU_LEVEL_WHICH:
switch (which) {
case CPU_WHICH_TID:
thread_lock(ttd);
CPU_COPY(&ttd->td_cpuset->cs_mask, mask);
thread_unlock(ttd);
break;
case CPU_WHICH_PID:
FOREACH_THREAD_IN_PROC(p, ttd) {
thread_lock(ttd);
CPU_OR(mask, &ttd->td_cpuset->cs_mask);
thread_unlock(ttd);
}
break;
case CPU_WHICH_CPUSET:
case CPU_WHICH_JAIL:
CPU_COPY(&set->cs_mask, mask);
break;
case CPU_WHICH_IRQ:
case CPU_WHICH_INTRHANDLER:
case CPU_WHICH_ITHREAD:
error = intr_getaffinity(id, which, mask);
break;
case CPU_WHICH_DOMAIN:
if (id < 0 || id >= MAXMEMDOM)
error = ESRCH;
else
CPU_COPY(&cpuset_domain[id], mask);
break;
}
break;
default:
error = EINVAL;
break;
}
if (set)
cpuset_rel(set);
if (p)
PROC_UNLOCK(p);
if (error == 0)
error = copyout(mask, maskp, size);
out:
free(mask, M_TEMP);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct cpuset_setaffinity_args {
cpulevel_t level;
cpuwhich_t which;
id_t id;
size_t cpusetsize;
const cpuset_t *mask;
};
#endif
int
sys_cpuset_setaffinity(struct thread *td, struct cpuset_setaffinity_args *uap)
{
return (kern_cpuset_setaffinity(td, uap->level, uap->which,
uap->id, uap->cpusetsize, uap->mask));
}
int
kern_cpuset_setaffinity(struct thread *td, cpulevel_t level, cpuwhich_t which,
id_t id, size_t cpusetsize, const cpuset_t *maskp)
{
struct cpuset *nset;
struct cpuset *set;
struct thread *ttd;
struct proc *p;
cpuset_t *mask;
int error;
if (cpusetsize < sizeof(cpuset_t) || cpusetsize > CPU_MAXSIZE / NBBY)
return (ERANGE);
error = cpuset_check_capabilities(td, level, which, id);
if (error != 0)
return (error);
mask = malloc(cpusetsize, M_TEMP, M_WAITOK | M_ZERO);
error = copyin(maskp, mask, cpusetsize);
if (error)
goto out;
/*
* Verify that no high bits are set.
*/
if (cpusetsize > sizeof(cpuset_t)) {
char *end;
char *cp;
end = cp = (char *)&mask->__bits;
end += cpusetsize;
cp += sizeof(cpuset_t);
while (cp != end)
if (*cp++ != 0) {
error = EINVAL;
goto out;
}
}
if (CPU_EMPTY(mask)) {
error = EDEADLK;
goto out;
}
switch (level) {
case CPU_LEVEL_ROOT:
case CPU_LEVEL_CPUSET:
error = cpuset_which(which, id, &p, &ttd, &set);
if (error)
break;
switch (which) {
case CPU_WHICH_TID:
case CPU_WHICH_PID:
thread_lock(ttd);
set = cpuset_ref(ttd->td_cpuset);
thread_unlock(ttd);
PROC_UNLOCK(p);
break;
case CPU_WHICH_CPUSET:
case CPU_WHICH_JAIL:
break;
case CPU_WHICH_IRQ:
case CPU_WHICH_INTRHANDLER:
case CPU_WHICH_ITHREAD:
case CPU_WHICH_DOMAIN:
error = EINVAL;
goto out;
}
if (level == CPU_LEVEL_ROOT)
nset = cpuset_refroot(set);
else
nset = cpuset_refbase(set);
error = cpuset_modify(nset, mask);
cpuset_rel(nset);
cpuset_rel(set);
break;
case CPU_LEVEL_WHICH:
switch (which) {
case CPU_WHICH_TID:
error = cpuset_setthread(id, mask);
break;
case CPU_WHICH_PID:
error = cpuset_setproc(id, NULL, mask, NULL, false);
break;
case CPU_WHICH_CPUSET:
case CPU_WHICH_JAIL:
error = cpuset_which(which, id, &p, &ttd, &set);
if (error == 0) {
error = cpuset_modify(set, mask);
cpuset_rel(set);
}
break;
case CPU_WHICH_IRQ:
case CPU_WHICH_INTRHANDLER:
case CPU_WHICH_ITHREAD:
error = intr_setaffinity(id, which, mask);
break;
default:
error = EINVAL;
break;
}
break;
default:
error = EINVAL;
break;
}
out:
free(mask, M_TEMP);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct cpuset_getdomain_args {
cpulevel_t level;
cpuwhich_t which;
id_t id;
size_t domainsetsize;
domainset_t *mask;
int *policy;
};
#endif
int
sys_cpuset_getdomain(struct thread *td, struct cpuset_getdomain_args *uap)
{
return (kern_cpuset_getdomain(td, uap->level, uap->which,
uap->id, uap->domainsetsize, uap->mask, uap->policy));
}
int
kern_cpuset_getdomain(struct thread *td, cpulevel_t level, cpuwhich_t which,
id_t id, size_t domainsetsize, domainset_t *maskp, int *policyp)
{
struct domainset outset;
struct thread *ttd;
struct cpuset *nset;
struct cpuset *set;
struct domainset *dset;
struct proc *p;
domainset_t *mask;
int error;
if (domainsetsize < sizeof(domainset_t) ||
domainsetsize > DOMAINSET_MAXSIZE / NBBY)
return (ERANGE);
error = cpuset_check_capabilities(td, level, which, id);
if (error != 0)
return (error);
mask = malloc(domainsetsize, M_TEMP, M_WAITOK | M_ZERO);
bzero(&outset, sizeof(outset));
error = cpuset_which(which, id, &p, &ttd, &set);
if (error)
goto out;
switch (level) {
case CPU_LEVEL_ROOT:
case CPU_LEVEL_CPUSET:
switch (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:
case CPU_WHICH_JAIL:
break;
case CPU_WHICH_IRQ:
case CPU_WHICH_INTRHANDLER:
case CPU_WHICH_ITHREAD:
case CPU_WHICH_DOMAIN:
error = EINVAL;
goto out;
}
if (level == CPU_LEVEL_ROOT)
nset = cpuset_refroot(set);
else
nset = cpuset_refbase(set);
domainset_copy(nset->cs_domain, &outset);
cpuset_rel(nset);
break;
case CPU_LEVEL_WHICH:
switch (which) {
case CPU_WHICH_TID:
thread_lock(ttd);
domainset_copy(ttd->td_cpuset->cs_domain, &outset);
thread_unlock(ttd);
break;
case CPU_WHICH_PID:
FOREACH_THREAD_IN_PROC(p, ttd) {
thread_lock(ttd);
dset = ttd->td_cpuset->cs_domain;
/* Show all domains in the proc. */
DOMAINSET_OR(&outset.ds_mask, &dset->ds_mask);
/* Last policy wins. */
outset.ds_policy = dset->ds_policy;
outset.ds_prefer = dset->ds_prefer;
thread_unlock(ttd);
}
break;
case CPU_WHICH_CPUSET:
case CPU_WHICH_JAIL:
domainset_copy(set->cs_domain, &outset);
break;
case CPU_WHICH_IRQ:
case CPU_WHICH_INTRHANDLER:
case CPU_WHICH_ITHREAD:
case CPU_WHICH_DOMAIN:
error = EINVAL;
break;
}
break;
default:
error = EINVAL;
break;
}
if (set)
cpuset_rel(set);
if (p)
PROC_UNLOCK(p);
/*
* Translate prefer into a set containing only the preferred domain,
* not the entire fallback set.
*/
if (outset.ds_policy == DOMAINSET_POLICY_PREFER) {
DOMAINSET_ZERO(&outset.ds_mask);
DOMAINSET_SET(outset.ds_prefer, &outset.ds_mask);
}
DOMAINSET_COPY(&outset.ds_mask, mask);
if (error == 0)
error = copyout(mask, maskp, domainsetsize);
if (error == 0)
if (suword32(policyp, outset.ds_policy) != 0)
error = EFAULT;
out:
free(mask, M_TEMP);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct cpuset_setdomain_args {
cpulevel_t level;
cpuwhich_t which;
id_t id;
size_t domainsetsize;
domainset_t *mask;
int policy;
};
#endif
int
sys_cpuset_setdomain(struct thread *td, struct cpuset_setdomain_args *uap)
{
return (kern_cpuset_setdomain(td, uap->level, uap->which,
uap->id, uap->domainsetsize, uap->mask, uap->policy));
}
int
kern_cpuset_setdomain(struct thread *td, cpulevel_t level, cpuwhich_t which,
id_t id, size_t domainsetsize, const domainset_t *maskp, int policy)
{
struct cpuset *nset;
struct cpuset *set;
struct thread *ttd;
struct proc *p;
struct domainset domain;
domainset_t *mask;
int error;
if (domainsetsize < sizeof(domainset_t) ||
domainsetsize > DOMAINSET_MAXSIZE / NBBY)
return (ERANGE);
if (policy <= DOMAINSET_POLICY_INVALID ||
policy > DOMAINSET_POLICY_MAX)
return (EINVAL);
error = cpuset_check_capabilities(td, level, which, id);
if (error != 0)
return (error);
memset(&domain, 0, sizeof(domain));
mask = malloc(domainsetsize, M_TEMP, M_WAITOK | M_ZERO);
error = copyin(maskp, mask, domainsetsize);
if (error)
goto out;
/*
* Verify that no high bits are set.
*/
if (domainsetsize > sizeof(domainset_t)) {
char *end;
char *cp;
end = cp = (char *)&mask->__bits;
end += domainsetsize;
cp += sizeof(domainset_t);
while (cp != end)
if (*cp++ != 0) {
error = EINVAL;
goto out;
}
}
if (DOMAINSET_EMPTY(mask)) {
error = EDEADLK;
goto out;
}
DOMAINSET_COPY(mask, &domain.ds_mask);
domain.ds_policy = policy;
/*
* Sanitize the provided mask.
*/
if (!DOMAINSET_SUBSET(&all_domains, &domain.ds_mask)) {
error = EINVAL;
goto out;
}
/* Translate preferred policy into a mask and fallback. */
if (policy == DOMAINSET_POLICY_PREFER) {
/* Only support a single preferred domain. */
if (DOMAINSET_COUNT(&domain.ds_mask) != 1) {
error = EINVAL;
goto out;
}
domain.ds_prefer = DOMAINSET_FFS(&domain.ds_mask) - 1;
/* This will be constrained by domainset_shadow(). */
DOMAINSET_COPY(&all_domains, &domain.ds_mask);
}
/*
* When given an impossible policy, fall back to interleaving
* across all domains.
*/
if (domainset_empty_vm(&domain))
domainset_copy(&domainset2, &domain);
switch (level) {
case CPU_LEVEL_ROOT:
case CPU_LEVEL_CPUSET:
error = cpuset_which(which, id, &p, &ttd, &set);
if (error)
break;
switch (which) {
case CPU_WHICH_TID:
case CPU_WHICH_PID:
thread_lock(ttd);
set = cpuset_ref(ttd->td_cpuset);
thread_unlock(ttd);
PROC_UNLOCK(p);
break;
case CPU_WHICH_CPUSET:
case CPU_WHICH_JAIL:
break;
case CPU_WHICH_IRQ:
case CPU_WHICH_INTRHANDLER:
case CPU_WHICH_ITHREAD:
case CPU_WHICH_DOMAIN:
error = EINVAL;
goto out;
}
if (level == CPU_LEVEL_ROOT)
nset = cpuset_refroot(set);
else
nset = cpuset_refbase(set);
error = cpuset_modify_domain(nset, &domain);
cpuset_rel(nset);
cpuset_rel(set);
break;
case CPU_LEVEL_WHICH:
switch (which) {
case CPU_WHICH_TID:
error = _cpuset_setthread(id, NULL, &domain);
break;
case CPU_WHICH_PID:
error = cpuset_setproc(id, NULL, NULL, &domain, false);
break;
case CPU_WHICH_CPUSET:
case CPU_WHICH_JAIL:
error = cpuset_which(which, id, &p, &ttd, &set);
if (error == 0) {
error = cpuset_modify_domain(set, &domain);
cpuset_rel(set);
}
break;
case CPU_WHICH_IRQ:
case CPU_WHICH_INTRHANDLER:
case CPU_WHICH_ITHREAD:
default:
error = EINVAL;
break;
}
break;
default:
error = EINVAL;
break;
}
out:
free(mask, M_TEMP);
return (error);
}
#ifdef DDB
static void
ddb_display_bitset(const struct bitset *set, int size)
{
int bit, once;
for (once = 0, bit = 0; bit < size; bit++) {
if (CPU_ISSET(bit, set)) {
if (once == 0) {
db_printf("%d", bit);
once = 1;
} else
db_printf(",%d", bit);
}
}
if (once == 0)
db_printf("<none>");
}
void
ddb_display_cpuset(const cpuset_t *set)
{
ddb_display_bitset((const struct bitset *)set, CPU_SETSIZE);
}
static void
ddb_display_domainset(const domainset_t *set)
{
ddb_display_bitset((const struct bitset *)set, DOMAINSET_SETSIZE);
}
DB_SHOW_COMMAND(cpusets, db_show_cpusets)
{
struct cpuset *set;
LIST_FOREACH(set, &cpuset_ids, cs_link) {
db_printf("set=%p id=%-6u ref=%-6d flags=0x%04x parent id=%d\n",
set, set->cs_id, refcount_load(&set->cs_ref), set->cs_flags,
(set->cs_parent != NULL) ? set->cs_parent->cs_id : 0);
db_printf(" cpu mask=");
ddb_display_cpuset(&set->cs_mask);
db_printf("\n");
db_printf(" domain policy %d prefer %d mask=",
set->cs_domain->ds_policy, set->cs_domain->ds_prefer);
ddb_display_domainset(&set->cs_domain->ds_mask);
db_printf("\n");
if (db_pager_quit)
break;
}
}
DB_SHOW_COMMAND(domainsets, db_show_domainsets)
{
struct domainset *set;
LIST_FOREACH(set, &cpuset_domains, ds_link) {
db_printf("set=%p policy %d prefer %d cnt %d\n",
set, set->ds_policy, set->ds_prefer, set->ds_cnt);
db_printf(" mask =");
ddb_display_domainset(&set->ds_mask);
db_printf("\n");
}
}
#endif /* DDB */