kern_cpuset.c revision 214409
178556Sobrien/*- 278556Sobrien * Copyright (c) 2008, Jeffrey Roberson <jeff@freebsd.org> 378556Sobrien * All rights reserved. 478556Sobrien * 578556Sobrien * Copyright (c) 2008 Nokia Corporation 678556Sobrien * All rights reserved. 778556Sobrien * 878556Sobrien * Redistribution and use in source and binary forms, with or without 978556Sobrien * modification, are permitted provided that the following conditions 1078556Sobrien * are met: 11146293Sobrien * 1. Redistributions of source code must retain the above copyright 1278556Sobrien * notice unmodified, this list of conditions, and the following 1378556Sobrien * disclaimer. 1478556Sobrien * 2. Redistributions in binary form must reproduce the above copyright 1578556Sobrien * notice, this list of conditions and the following disclaimer in the 1678556Sobrien * documentation and/or other materials provided with the distribution. 1778556Sobrien * 1878556Sobrien * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 1978556Sobrien * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 2078556Sobrien * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 2178556Sobrien * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 2278556Sobrien * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 2378556Sobrien * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 2478556Sobrien * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 2578556Sobrien * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 2678556Sobrien * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 2778556Sobrien * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 2878556Sobrien * 2978556Sobrien */ 3078556Sobrien 3178556Sobrien#include <sys/cdefs.h> 3278556Sobrien__FBSDID("$FreeBSD: head/sys/kern/kern_cpuset.c 214409 2010-10-27 02:32:54Z davidxu $"); 3378556Sobrien 3478556Sobrien#include "opt_ddb.h" 3578556Sobrien 3678556Sobrien#include <sys/param.h> 3778556Sobrien#include <sys/systm.h> 3878556Sobrien#include <sys/sysproto.h> 3978556Sobrien#include <sys/jail.h> 4078556Sobrien#include <sys/kernel.h> 4178556Sobrien#include <sys/lock.h> 4278556Sobrien#include <sys/malloc.h> 4378556Sobrien#include <sys/mutex.h> 4478556Sobrien#include <sys/priv.h> 45146293Sobrien#include <sys/proc.h> 4678556Sobrien#include <sys/refcount.h> 4778556Sobrien#include <sys/sched.h> 4878556Sobrien#include <sys/smp.h> 4978556Sobrien#include <sys/syscallsubr.h> 5078556Sobrien#include <sys/cpuset.h> 5178556Sobrien#include <sys/sx.h> 5278556Sobrien#include <sys/queue.h> 5378556Sobrien#include <sys/limits.h> 5478556Sobrien#include <sys/bus.h> 5578556Sobrien#include <sys/interrupt.h> 5678556Sobrien 5778556Sobrien#include <vm/uma.h> 5878556Sobrien 5978556Sobrien#ifdef DDB 6078556Sobrien#include <ddb/ddb.h> 6178556Sobrien#endif /* DDB */ 6278556Sobrien 6378556Sobrien/* 6478556Sobrien * cpusets provide a mechanism for creating and manipulating sets of 6578556Sobrien * processors for the purpose of constraining the scheduling of threads to 6678556Sobrien * specific processors. 6778556Sobrien * 6878556Sobrien * Each process belongs to an identified set, by default this is set 1. Each 6978556Sobrien * thread may further restrict the cpus it may run on to a subset of this 7078556Sobrien * named set. This creates an anonymous set which other threads and processes 7178556Sobrien * may not join by number. 7278556Sobrien * 7378556Sobrien * The named set is referred to herein as the 'base' set to avoid ambiguity. 7478556Sobrien * This set is usually a child of a 'root' set while the anonymous set may 7578556Sobrien * simply be referred to as a mask. In the syscall api these are referred to 7678556Sobrien * as the ROOT, CPUSET, and MASK levels where CPUSET is called 'base' here. 7778556Sobrien * 7878556Sobrien * Threads inherit their set from their creator whether it be anonymous or 7978556Sobrien * not. This means that anonymous sets are immutable because they may be 8078556Sobrien * shared. To modify an anonymous set a new set is created with the desired 8178556Sobrien * mask and the same parent as the existing anonymous set. This gives the 8278556Sobrien * illusion of each thread having a private mask. 8378556Sobrien * 8478556Sobrien * Via the syscall apis a user may ask to retrieve or modify the root, base, 8578556Sobrien * or mask that is discovered via a pid, tid, or setid. Modifying a set 8678556Sobrien * modifies all numbered and anonymous child sets to comply with the new mask. 8778556Sobrien * Modifying a pid or tid's mask applies only to that tid but must still 8878556Sobrien * exist within the assigned parent set. 8978556Sobrien * 9078556Sobrien * A thread may not be assigned to a group separate from other threads in 9178556Sobrien * the process. This is to remove ambiguity when the setid is queried with 9278556Sobrien * a pid argument. There is no other technical limitation. 9378556Sobrien * 9478556Sobrien * This somewhat complex arrangement is intended to make it easy for 9578556Sobrien * applications to query available processors and bind their threads to 9678556Sobrien * specific processors while also allowing administrators to dynamically 9778556Sobrien * reprovision by changing sets which apply to groups of processes. 9878556Sobrien * 9978556Sobrien * A simple application should not concern itself with sets at all and 10078556Sobrien * rather apply masks to its own threads via CPU_WHICH_TID and a -1 id 10178556Sobrien * meaning 'curthread'. It may query available cpus for that tid with a 10278556Sobrien * getaffinity call using (CPU_LEVEL_CPUSET, CPU_WHICH_PID, -1, ...). 10378556Sobrien */ 10478556Sobrienstatic uma_zone_t cpuset_zone; 10578556Sobrienstatic struct mtx cpuset_lock; 10678556Sobrienstatic struct setlist cpuset_ids; 10778556Sobrienstatic struct unrhdr *cpuset_unr; 10878556Sobrienstatic struct cpuset *cpuset_zero; 10978556Sobrien 11078556Sobriencpuset_t *cpuset_root; 11178556Sobrien 11278556Sobrien/* 11378556Sobrien * Acquire a reference to a cpuset, all pointers must be tracked with refs. 11478556Sobrien */ 11578556Sobrienstruct cpuset * 11678556Sobriencpuset_ref(struct cpuset *set) 11778556Sobrien{ 11878556Sobrien 11978556Sobrien refcount_acquire(&set->cs_ref); 12078556Sobrien return (set); 12178556Sobrien} 12278556Sobrien 12378556Sobrien/* 12478556Sobrien * Walks up the tree from 'set' to find the root. Returns the root 12578556Sobrien * referenced. 12678556Sobrien */ 12778556Sobrienstatic struct cpuset * 12878556Sobriencpuset_refroot(struct cpuset *set) 12978556Sobrien{ 13078556Sobrien 13178556Sobrien for (; set->cs_parent != NULL; set = set->cs_parent) 13278556Sobrien if (set->cs_flags & CPU_SET_ROOT) 13378556Sobrien break; 13478556Sobrien cpuset_ref(set); 13578556Sobrien 13678556Sobrien return (set); 13778556Sobrien} 13878556Sobrien 13978556Sobrien/* 14078556Sobrien * Find the first non-anonymous set starting from 'set'. Returns this set 14178556Sobrien * referenced. May return the passed in set with an extra ref if it is 14278556Sobrien * not anonymous. 14378556Sobrien */ 14478556Sobrienstatic struct cpuset * 14578556Sobriencpuset_refbase(struct cpuset *set) 14678556Sobrien{ 14778556Sobrien 14878556Sobrien if (set->cs_id == CPUSET_INVALID) 14978556Sobrien set = set->cs_parent; 15078556Sobrien cpuset_ref(set); 15178556Sobrien 15278556Sobrien return (set); 15378556Sobrien} 15478556Sobrien 15578556Sobrien/* 15678556Sobrien * Release a reference in a context where it is safe to allocate. 15778556Sobrien */ 15878556Sobrienvoid 15978556Sobriencpuset_rel(struct cpuset *set) 16078556Sobrien{ 16178556Sobrien cpusetid_t id; 16278556Sobrien 16378556Sobrien if (refcount_release(&set->cs_ref) == 0) 16478556Sobrien return; 16578556Sobrien mtx_lock_spin(&cpuset_lock); 16678556Sobrien LIST_REMOVE(set, cs_siblings); 16778556Sobrien id = set->cs_id; 16878556Sobrien if (id != CPUSET_INVALID) 16978556Sobrien LIST_REMOVE(set, cs_link); 17078556Sobrien mtx_unlock_spin(&cpuset_lock); 17178556Sobrien cpuset_rel(set->cs_parent); 17278556Sobrien uma_zfree(cpuset_zone, set); 17378556Sobrien if (id != CPUSET_INVALID) 17478556Sobrien free_unr(cpuset_unr, id); 17578556Sobrien} 17678556Sobrien 17778556Sobrien/* 17878556Sobrien * Deferred release must be used when in a context that is not safe to 17978556Sobrien * allocate/free. This places any unreferenced sets on the list 'head'. 18078556Sobrien */ 18178556Sobrienstatic void 18278556Sobriencpuset_rel_defer(struct setlist *head, struct cpuset *set) 18378556Sobrien{ 18478556Sobrien 18578556Sobrien if (refcount_release(&set->cs_ref) == 0) 18678556Sobrien return; 18778556Sobrien mtx_lock_spin(&cpuset_lock); 18878556Sobrien LIST_REMOVE(set, cs_siblings); 18978556Sobrien if (set->cs_id != CPUSET_INVALID) 19078556Sobrien LIST_REMOVE(set, cs_link); 19178556Sobrien LIST_INSERT_HEAD(head, set, cs_link); 19278556Sobrien mtx_unlock_spin(&cpuset_lock); 19378556Sobrien} 19478556Sobrien 19578556Sobrien/* 19678556Sobrien * Complete a deferred release. Removes the set from the list provided to 19778556Sobrien * cpuset_rel_defer. 19878556Sobrien */ 19978556Sobrienstatic void 20078556Sobriencpuset_rel_complete(struct cpuset *set) 20178556Sobrien{ 20278556Sobrien LIST_REMOVE(set, cs_link); 20378556Sobrien cpuset_rel(set->cs_parent); 20478556Sobrien uma_zfree(cpuset_zone, set); 20578556Sobrien} 20678556Sobrien 20778556Sobrien/* 20878556Sobrien * Find a set based on an id. Returns it with a ref. 20978556Sobrien */ 21078556Sobrienstatic struct cpuset * 21178556Sobriencpuset_lookup(cpusetid_t setid, struct thread *td) 21278556Sobrien{ 21378556Sobrien struct cpuset *set; 21478556Sobrien 21578556Sobrien if (setid == CPUSET_INVALID) 21678556Sobrien return (NULL); 21778556Sobrien mtx_lock_spin(&cpuset_lock); 21878556Sobrien LIST_FOREACH(set, &cpuset_ids, cs_link) 21978556Sobrien if (set->cs_id == setid) 22078556Sobrien break; 22178556Sobrien if (set) 22278556Sobrien cpuset_ref(set); 22378556Sobrien mtx_unlock_spin(&cpuset_lock); 22478556Sobrien 22578556Sobrien KASSERT(td != NULL, ("[%s:%d] td is NULL", __func__, __LINE__)); 22678556Sobrien if (set != NULL && jailed(td->td_ucred)) { 22778556Sobrien struct cpuset *jset, *tset; 22878556Sobrien 22978556Sobrien jset = td->td_ucred->cr_prison->pr_cpuset; 23078556Sobrien for (tset = set; tset != NULL; tset = tset->cs_parent) 23178556Sobrien if (tset == jset) 23278556Sobrien break; 23378556Sobrien if (tset == NULL) { 23478556Sobrien cpuset_rel(set); 23578556Sobrien set = NULL; 23678556Sobrien } 23778556Sobrien } 23878556Sobrien 23978556Sobrien return (set); 24078556Sobrien} 24178556Sobrien 24278556Sobrien/* 24378556Sobrien * Create a set in the space provided in 'set' with the provided parameters. 24478556Sobrien * The set is returned with a single ref. May return EDEADLK if the set 24578556Sobrien * will have no valid cpu based on restrictions from the parent. 24678556Sobrien */ 24778556Sobrienstatic int 24878556Sobrien_cpuset_create(struct cpuset *set, struct cpuset *parent, cpuset_t *mask, 24978556Sobrien cpusetid_t id) 25078556Sobrien{ 25178556Sobrien 25278556Sobrien if (!CPU_OVERLAP(&parent->cs_mask, mask)) 25378556Sobrien return (EDEADLK); 25478556Sobrien CPU_COPY(mask, &set->cs_mask); 25578556Sobrien LIST_INIT(&set->cs_children); 25678556Sobrien refcount_init(&set->cs_ref, 1); 25778556Sobrien set->cs_flags = 0; 25878556Sobrien mtx_lock_spin(&cpuset_lock); 25978556Sobrien CPU_AND(mask, &parent->cs_mask); 26078556Sobrien set->cs_id = id; 26178556Sobrien set->cs_parent = cpuset_ref(parent); 26278556Sobrien LIST_INSERT_HEAD(&parent->cs_children, set, cs_siblings); 26378556Sobrien if (set->cs_id != CPUSET_INVALID) 26478556Sobrien LIST_INSERT_HEAD(&cpuset_ids, set, cs_link); 26578556Sobrien mtx_unlock_spin(&cpuset_lock); 26678556Sobrien 26778556Sobrien return (0); 26878556Sobrien} 26978556Sobrien 27078556Sobrien/* 27178556Sobrien * Create a new non-anonymous set with the requested parent and mask. May 27278556Sobrien * return failures if the mask is invalid or a new number can not be 27378556Sobrien * allocated. 27478556Sobrien */ 27578556Sobrienstatic int 27678556Sobriencpuset_create(struct cpuset **setp, struct cpuset *parent, cpuset_t *mask) 27778556Sobrien{ 27878556Sobrien struct cpuset *set; 27978556Sobrien cpusetid_t id; 28078556Sobrien int error; 28178556Sobrien 28278556Sobrien id = alloc_unr(cpuset_unr); 28378556Sobrien if (id == -1) 28478556Sobrien return (ENFILE); 28578556Sobrien *setp = set = uma_zalloc(cpuset_zone, M_WAITOK); 28678556Sobrien error = _cpuset_create(set, parent, mask, id); 28778556Sobrien if (error == 0) 28878556Sobrien return (0); 28978556Sobrien free_unr(cpuset_unr, id); 29078556Sobrien uma_zfree(cpuset_zone, set); 29178556Sobrien 29278556Sobrien return (error); 29378556Sobrien} 29478556Sobrien 29578556Sobrien/* 29678556Sobrien * Recursively check for errors that would occur from applying mask to 29778556Sobrien * the tree of sets starting at 'set'. Checks for sets that would become 29878556Sobrien * empty as well as RDONLY flags. 29978556Sobrien */ 30078556Sobrienstatic int 30178556Sobriencpuset_testupdate(struct cpuset *set, cpuset_t *mask) 30278556Sobrien{ 30378556Sobrien struct cpuset *nset; 30478556Sobrien cpuset_t newmask; 30578556Sobrien int error; 30678556Sobrien 30778556Sobrien mtx_assert(&cpuset_lock, MA_OWNED); 30878556Sobrien if (set->cs_flags & CPU_SET_RDONLY) 30978556Sobrien return (EPERM); 31078556Sobrien if (!CPU_OVERLAP(&set->cs_mask, mask)) 31178556Sobrien return (EDEADLK); 31278556Sobrien CPU_COPY(&set->cs_mask, &newmask); 31378556Sobrien CPU_AND(&newmask, mask); 31478556Sobrien error = 0; 31578556Sobrien LIST_FOREACH(nset, &set->cs_children, cs_siblings) 31678556Sobrien if ((error = cpuset_testupdate(nset, &newmask)) != 0) 31778556Sobrien break; 31878556Sobrien return (error); 31978556Sobrien} 32078556Sobrien 32178556Sobrien/* 32278556Sobrien * Applies the mask 'mask' without checking for empty sets or permissions. 32378556Sobrien */ 32478556Sobrienstatic void 32578556Sobriencpuset_update(struct cpuset *set, cpuset_t *mask) 32678556Sobrien{ 32778556Sobrien struct cpuset *nset; 32878556Sobrien 32978556Sobrien mtx_assert(&cpuset_lock, MA_OWNED); 33078556Sobrien CPU_AND(&set->cs_mask, mask); 33178556Sobrien LIST_FOREACH(nset, &set->cs_children, cs_siblings) 33278556Sobrien cpuset_update(nset, &set->cs_mask); 33378556Sobrien 33478556Sobrien return; 33578556Sobrien} 33678556Sobrien 33778556Sobrien/* 33878556Sobrien * Modify the set 'set' to use a copy of the mask provided. Apply this new 33978556Sobrien * mask to restrict all children in the tree. Checks for validity before 34078556Sobrien * applying the changes. 34178556Sobrien */ 34278556Sobrienstatic int 34378556Sobriencpuset_modify(struct cpuset *set, cpuset_t *mask) 34478556Sobrien{ 34578556Sobrien struct cpuset *root; 34678556Sobrien int error; 34778556Sobrien 34878556Sobrien error = priv_check(curthread, PRIV_SCHED_CPUSET); 34978556Sobrien if (error) 35078556Sobrien return (error); 35178556Sobrien /* 35278556Sobrien * In case we are called from within the jail 35378556Sobrien * we do not allow modifying the dedicated root 35478556Sobrien * cpuset of the jail but may still allow to 35578556Sobrien * change child sets. 35678556Sobrien */ 35778556Sobrien if (jailed(curthread->td_ucred) && 35878556Sobrien set->cs_flags & CPU_SET_ROOT) 35978556Sobrien return (EPERM); 36078556Sobrien /* 36178556Sobrien * Verify that we have access to this set of 36278556Sobrien * cpus. 36378556Sobrien */ 36478556Sobrien root = set->cs_parent; 36578556Sobrien if (root && !CPU_SUBSET(&root->cs_mask, mask)) 36678556Sobrien return (EINVAL); 36778556Sobrien mtx_lock_spin(&cpuset_lock); 36878556Sobrien error = cpuset_testupdate(set, mask); 36978556Sobrien if (error) 37078556Sobrien goto out; 37178556Sobrien cpuset_update(set, mask); 37278556Sobrien CPU_COPY(mask, &set->cs_mask); 37378556Sobrienout: 37478556Sobrien mtx_unlock_spin(&cpuset_lock); 37578556Sobrien 37678556Sobrien return (error); 37778556Sobrien} 37878556Sobrien 37978556Sobrien/* 38078556Sobrien * Resolve the 'which' parameter of several cpuset apis. 38178556Sobrien * 38278556Sobrien * For WHICH_PID and WHICH_TID return a locked proc and valid proc/tid. Also 38378556Sobrien * checks for permission via p_cansched(). 38478556Sobrien * 38578556Sobrien * For WHICH_SET returns a valid set with a new reference. 38678556Sobrien * 38778556Sobrien * -1 may be supplied for any argument to mean the current proc/thread or 38878556Sobrien * the base set of the current thread. May fail with ESRCH/EPERM. 38978556Sobrien */ 39078556Sobrienstatic int 39178556Sobriencpuset_which(cpuwhich_t which, id_t id, struct proc **pp, struct thread **tdp, 39278556Sobrien struct cpuset **setp) 39378556Sobrien{ 39478556Sobrien struct cpuset *set; 39578556Sobrien struct thread *td; 39678556Sobrien struct proc *p; 39778556Sobrien int error; 39878556Sobrien 39978556Sobrien *pp = p = NULL; 40078556Sobrien *tdp = td = NULL; 40178556Sobrien *setp = set = NULL; 40278556Sobrien switch (which) { 40378556Sobrien case CPU_WHICH_PID: 40478556Sobrien if (id == -1) { 40578556Sobrien PROC_LOCK(curproc); 40678556Sobrien p = curproc; 40778556Sobrien break; 40878556Sobrien } 40978556Sobrien if ((p = pfind(id)) == NULL) 41078556Sobrien return (ESRCH); 41178556Sobrien break; 41278556Sobrien case CPU_WHICH_TID: 41378556Sobrien if (id == -1) { 41478556Sobrien PROC_LOCK(curproc); 41578556Sobrien p = curproc; 41678556Sobrien td = curthread; 41778556Sobrien break; 41878556Sobrien } 41978556Sobrien td = tdfind(id, -1); 42078556Sobrien if (td == NULL) 42178556Sobrien return (ESRCH); 42278556Sobrien p = td->td_proc; 42378556Sobrien break; 42478556Sobrien case CPU_WHICH_CPUSET: 42578556Sobrien if (id == -1) { 42678556Sobrien thread_lock(curthread); 42778556Sobrien set = cpuset_refbase(curthread->td_cpuset); 42878556Sobrien thread_unlock(curthread); 42978556Sobrien } else 43078556Sobrien set = cpuset_lookup(id, curthread); 43178556Sobrien if (set) { 43278556Sobrien *setp = set; 43378556Sobrien return (0); 43478556Sobrien } 43578556Sobrien return (ESRCH); 43678556Sobrien case CPU_WHICH_JAIL: 43778556Sobrien { 43878556Sobrien /* Find `set' for prison with given id. */ 43978556Sobrien struct prison *pr; 44078556Sobrien 44178556Sobrien sx_slock(&allprison_lock); 44278556Sobrien pr = prison_find_child(curthread->td_ucred->cr_prison, id); 44378556Sobrien sx_sunlock(&allprison_lock); 44478556Sobrien if (pr == NULL) 44578556Sobrien return (ESRCH); 44678556Sobrien cpuset_ref(pr->pr_cpuset); 44778556Sobrien *setp = pr->pr_cpuset; 44878556Sobrien mtx_unlock(&pr->pr_mtx); 44978556Sobrien return (0); 45078556Sobrien } 45178556Sobrien case CPU_WHICH_IRQ: 45278556Sobrien return (0); 45378556Sobrien default: 45478556Sobrien return (EINVAL); 45578556Sobrien } 45678556Sobrien error = p_cansched(curthread, p); 45778556Sobrien if (error) { 45878556Sobrien PROC_UNLOCK(p); 45978556Sobrien return (error); 46078556Sobrien } 46178556Sobrien if (td == NULL) 46278556Sobrien td = FIRST_THREAD_IN_PROC(p); 46378556Sobrien *pp = p; 46478556Sobrien *tdp = td; 46578556Sobrien return (0); 46678556Sobrien} 46778556Sobrien 46878556Sobrien/* 46978556Sobrien * Create an anonymous set with the provided mask in the space provided by 47078556Sobrien * 'fset'. If the passed in set is anonymous we use its parent otherwise 47178556Sobrien * the new set is a child of 'set'. 47278556Sobrien */ 47378556Sobrienstatic int 47478556Sobriencpuset_shadow(struct cpuset *set, struct cpuset *fset, cpuset_t *mask) 47578556Sobrien{ 47678556Sobrien struct cpuset *parent; 47778556Sobrien 47878556Sobrien if (set->cs_id == CPUSET_INVALID) 47978556Sobrien parent = set->cs_parent; 48078556Sobrien else 48178556Sobrien parent = set; 48278556Sobrien if (!CPU_SUBSET(&parent->cs_mask, mask)) 48378556Sobrien return (EDEADLK); 48478556Sobrien return (_cpuset_create(fset, parent, mask, CPUSET_INVALID)); 48578556Sobrien} 48678556Sobrien 48778556Sobrien/* 48878556Sobrien * Handle two cases for replacing the base set or mask of an entire process. 48978556Sobrien * 49078556Sobrien * 1) Set is non-null and mask is null. This reparents all anonymous sets 491146293Sobrien * to the provided set and replaces all non-anonymous td_cpusets with the 492146293Sobrien * provided set. 49378556Sobrien * 2) Mask is non-null and set is null. This replaces or creates anonymous 49478556Sobrien * sets for every thread with the existing base as a parent. 495146293Sobrien * 49678556Sobrien * This is overly complicated because we can't allocate while holding a 49778556Sobrien * spinlock and spinlocks must be held while changing and examining thread 49878556Sobrien * state. 49978556Sobrien */ 50078556Sobrienstatic int 50178556Sobriencpuset_setproc(pid_t pid, struct cpuset *set, cpuset_t *mask) 50278556Sobrien{ 50378556Sobrien struct setlist freelist; 50478556Sobrien struct setlist droplist; 50578556Sobrien struct cpuset *tdset; 50678556Sobrien struct cpuset *nset; 50778556Sobrien struct thread *td; 50878556Sobrien struct proc *p; 50978556Sobrien int threads; 51078556Sobrien int nfree; 51178556Sobrien int error; 51278556Sobrien /* 51378556Sobrien * The algorithm requires two passes due to locking considerations. 51478556Sobrien * 51578556Sobrien * 1) Lookup the process and acquire the locks in the required order. 51678556Sobrien * 2) If enough cpusets have not been allocated release the locks and 51778556Sobrien * allocate them. Loop. 51878556Sobrien */ 51978556Sobrien LIST_INIT(&freelist); 52078556Sobrien LIST_INIT(&droplist); 52178556Sobrien nfree = 0; 52278556Sobrien for (;;) { 52378556Sobrien error = cpuset_which(CPU_WHICH_PID, pid, &p, &td, &nset); 52478556Sobrien if (error) 52578556Sobrien goto out; 52678556Sobrien if (nfree >= p->p_numthreads) 52778556Sobrien break; 52878556Sobrien threads = p->p_numthreads; 52978556Sobrien PROC_UNLOCK(p); 53078556Sobrien for (; nfree < threads; nfree++) { 53178556Sobrien nset = uma_zalloc(cpuset_zone, M_WAITOK); 532146293Sobrien LIST_INSERT_HEAD(&freelist, nset, cs_link); 53378556Sobrien } 53478556Sobrien } 53578556Sobrien PROC_LOCK_ASSERT(p, MA_OWNED); 53678556Sobrien /* 53778556Sobrien * Now that the appropriate locks are held and we have enough cpusets, 53878556Sobrien * make sure the operation will succeed before applying changes. The 53978556Sobrien * proc lock prevents td_cpuset from changing between calls. 54078556Sobrien */ 54178556Sobrien error = 0; 54278556Sobrien FOREACH_THREAD_IN_PROC(p, td) { 54378556Sobrien thread_lock(td); 54478556Sobrien tdset = td->td_cpuset; 54578556Sobrien /* 54678556Sobrien * Verify that a new mask doesn't specify cpus outside of 54778556Sobrien * the set the thread is a member of. 54878556Sobrien */ 54978556Sobrien if (mask) { 55078556Sobrien if (tdset->cs_id == CPUSET_INVALID) 55178556Sobrien tdset = tdset->cs_parent; 55278556Sobrien if (!CPU_SUBSET(&tdset->cs_mask, mask)) 55378556Sobrien error = EDEADLK; 55478556Sobrien /* 55578556Sobrien * Verify that a new set won't leave an existing thread 55678556Sobrien * mask without a cpu to run on. It can, however, restrict 55778556Sobrien * the set. 55878556Sobrien */ 55978556Sobrien } else if (tdset->cs_id == CPUSET_INVALID) { 56078556Sobrien if (!CPU_OVERLAP(&set->cs_mask, &tdset->cs_mask)) 56178556Sobrien error = EDEADLK; 56278556Sobrien } 56378556Sobrien thread_unlock(td); 56478556Sobrien if (error) 56578556Sobrien goto unlock_out; 56678556Sobrien } 56778556Sobrien /* 56878556Sobrien * Replace each thread's cpuset while using deferred release. We 56978556Sobrien * must do this because the thread lock must be held while operating 57078556Sobrien * on the thread and this limits the type of operations allowed. 57178556Sobrien */ 57278556Sobrien FOREACH_THREAD_IN_PROC(p, td) { 57378556Sobrien thread_lock(td); 57478556Sobrien /* 57578556Sobrien * If we presently have an anonymous set or are applying a 57678556Sobrien * mask we must create an anonymous shadow set. That is 57778556Sobrien * either parented to our existing base or the supplied set. 57878556Sobrien * 57978556Sobrien * If we have a base set with no anonymous shadow we simply 58078556Sobrien * replace it outright. 58178556Sobrien */ 58278556Sobrien tdset = td->td_cpuset; 58378556Sobrien if (tdset->cs_id == CPUSET_INVALID || mask) { 58478556Sobrien nset = LIST_FIRST(&freelist); 58578556Sobrien LIST_REMOVE(nset, cs_link); 58678556Sobrien if (mask) 58778556Sobrien error = cpuset_shadow(tdset, nset, mask); 58878556Sobrien else 58978556Sobrien error = _cpuset_create(nset, set, 59078556Sobrien &tdset->cs_mask, CPUSET_INVALID); 59178556Sobrien if (error) { 59278556Sobrien LIST_INSERT_HEAD(&freelist, nset, cs_link); 59378556Sobrien thread_unlock(td); 59478556Sobrien break; 59578556Sobrien } 59678556Sobrien } else 59778556Sobrien nset = cpuset_ref(set); 59878556Sobrien cpuset_rel_defer(&droplist, tdset); 59978556Sobrien td->td_cpuset = nset; 60078556Sobrien sched_affinity(td); 60178556Sobrien thread_unlock(td); 60278556Sobrien } 60378556Sobrienunlock_out: 60478556Sobrien PROC_UNLOCK(p); 60578556Sobrienout: 60678556Sobrien while ((nset = LIST_FIRST(&droplist)) != NULL) 60778556Sobrien cpuset_rel_complete(nset); 60878556Sobrien while ((nset = LIST_FIRST(&freelist)) != NULL) { 60978556Sobrien LIST_REMOVE(nset, cs_link); 61078556Sobrien uma_zfree(cpuset_zone, nset); 61178556Sobrien } 61278556Sobrien return (error); 61378556Sobrien} 61478556Sobrien 61578556Sobrien/* 61678556Sobrien * Apply an anonymous mask to a single thread. 61778556Sobrien */ 61878556Sobrienint 61978556Sobriencpuset_setthread(lwpid_t id, cpuset_t *mask) 62078556Sobrien{ 62178556Sobrien struct cpuset *nset; 62278556Sobrien struct cpuset *set; 62378556Sobrien struct thread *td; 62478556Sobrien struct proc *p; 62578556Sobrien int error; 62678556Sobrien 62778556Sobrien nset = uma_zalloc(cpuset_zone, M_WAITOK); 62878556Sobrien error = cpuset_which(CPU_WHICH_TID, id, &p, &td, &set); 62978556Sobrien if (error) 63078556Sobrien goto out; 63178556Sobrien set = NULL; 63278556Sobrien thread_lock(td); 63378556Sobrien error = cpuset_shadow(td->td_cpuset, nset, mask); 63478556Sobrien if (error == 0) { 63578556Sobrien set = td->td_cpuset; 63678556Sobrien td->td_cpuset = nset; 63778556Sobrien sched_affinity(td); 63878556Sobrien nset = NULL; 63978556Sobrien } 64078556Sobrien thread_unlock(td); 64178556Sobrien PROC_UNLOCK(p); 64278556Sobrien if (set) 64378556Sobrien cpuset_rel(set); 64478556Sobrienout: 64578556Sobrien if (nset) 64678556Sobrien uma_zfree(cpuset_zone, nset); 64778556Sobrien return (error); 64878556Sobrien} 64978556Sobrien 65078556Sobrien/* 65178556Sobrien * Creates the cpuset for thread0. We make two sets: 65278556Sobrien * 65378556Sobrien * 0 - The root set which should represent all valid processors in the 65478556Sobrien * system. It is initially created with a mask of all processors 65578556Sobrien * because we don't know what processors are valid until cpuset_init() 656146293Sobrien * runs. This set is immutable. 657146293Sobrien * 1 - The default set which all processes are a member of until changed. 65878556Sobrien * This allows an administrator to move all threads off of given cpus to 65978556Sobrien * dedicate them to high priority tasks or save power etc. 66078556Sobrien */ 66178556Sobrienstruct cpuset * 66278556Sobriencpuset_thread0(void) 66378556Sobrien{ 66478556Sobrien struct cpuset *set; 66578556Sobrien int error; 66678556Sobrien 66778556Sobrien cpuset_zone = uma_zcreate("cpuset", sizeof(struct cpuset), NULL, NULL, 66890067Ssobomax NULL, NULL, UMA_ALIGN_PTR, 0); 66990067Ssobomax mtx_init(&cpuset_lock, "cpuset", NULL, MTX_SPIN | MTX_RECURSE); 67090067Ssobomax /* 67190067Ssobomax * Create the root system set for the whole machine. Doesn't use 67278556Sobrien * cpuset_create() due to NULL parent. 67378556Sobrien */ 67478556Sobrien set = uma_zalloc(cpuset_zone, M_WAITOK | M_ZERO); 67578556Sobrien set->cs_mask.__bits[0] = -1; 67678556Sobrien LIST_INIT(&set->cs_children); 67778556Sobrien LIST_INSERT_HEAD(&cpuset_ids, set, cs_link); 67878556Sobrien set->cs_ref = 1; 67978556Sobrien set->cs_flags = CPU_SET_ROOT; 68078556Sobrien cpuset_zero = set; 68178556Sobrien cpuset_root = &set->cs_mask; 68278556Sobrien /* 68378556Sobrien * Now derive a default, modifiable set from that to give out. 68478556Sobrien */ 68578556Sobrien set = uma_zalloc(cpuset_zone, M_WAITOK); 68678556Sobrien error = _cpuset_create(set, cpuset_zero, &cpuset_zero->cs_mask, 1); 68778556Sobrien KASSERT(error == 0, ("Error creating default set: %d\n", error)); 68878556Sobrien /* 68978556Sobrien * Initialize the unit allocator. 0 and 1 are allocated above. 69078556Sobrien */ 69178556Sobrien cpuset_unr = new_unrhdr(2, INT_MAX, NULL); 69278556Sobrien 69378556Sobrien return (set); 69478556Sobrien} 69578556Sobrien 69678556Sobrien/* 69778556Sobrien * Create a cpuset, which would be cpuset_create() but 69878556Sobrien * mark the new 'set' as root. 69978556Sobrien * 70078556Sobrien * We are not going to reparent the td to it. Use cpuset_setproc_update_set() 70178556Sobrien * for that. 70278556Sobrien * 70378556Sobrien * In case of no error, returns the set in *setp locked with a reference. 70478556Sobrien */ 70578556Sobrienint 70678556Sobriencpuset_create_root(struct prison *pr, struct cpuset **setp) 70778556Sobrien{ 708146293Sobrien struct cpuset *set; 70978556Sobrien int error; 71078556Sobrien 71178556Sobrien KASSERT(pr != NULL, ("[%s:%d] invalid pr", __func__, __LINE__)); 71278556Sobrien KASSERT(setp != NULL, ("[%s:%d] invalid setp", __func__, __LINE__)); 71378556Sobrien 71478556Sobrien error = cpuset_create(setp, pr->pr_cpuset, &pr->pr_cpuset->cs_mask); 71578556Sobrien if (error) 71678556Sobrien return (error); 717 718 KASSERT(*setp != NULL, ("[%s:%d] cpuset_create returned invalid data", 719 __func__, __LINE__)); 720 721 /* Mark the set as root. */ 722 set = *setp; 723 set->cs_flags |= CPU_SET_ROOT; 724 725 return (0); 726} 727 728int 729cpuset_setproc_update_set(struct proc *p, struct cpuset *set) 730{ 731 int error; 732 733 KASSERT(p != NULL, ("[%s:%d] invalid proc", __func__, __LINE__)); 734 KASSERT(set != NULL, ("[%s:%d] invalid set", __func__, __LINE__)); 735 736 cpuset_ref(set); 737 error = cpuset_setproc(p->p_pid, set, NULL); 738 if (error) 739 return (error); 740 cpuset_rel(set); 741 return (0); 742} 743 744/* 745 * This is called once the final set of system cpus is known. Modifies 746 * the root set and all children and mark the root read-only. 747 */ 748static void 749cpuset_init(void *arg) 750{ 751 cpuset_t mask; 752 753 CPU_ZERO(&mask); 754#ifdef SMP 755 mask.__bits[0] = all_cpus; 756#else 757 mask.__bits[0] = 1; 758#endif 759 if (cpuset_modify(cpuset_zero, &mask)) 760 panic("Can't set initial cpuset mask.\n"); 761 cpuset_zero->cs_flags |= CPU_SET_RDONLY; 762} 763SYSINIT(cpuset, SI_SUB_SMP, SI_ORDER_ANY, cpuset_init, NULL); 764 765#ifndef _SYS_SYSPROTO_H_ 766struct cpuset_args { 767 cpusetid_t *setid; 768}; 769#endif 770int 771cpuset(struct thread *td, struct cpuset_args *uap) 772{ 773 struct cpuset *root; 774 struct cpuset *set; 775 int error; 776 777 thread_lock(td); 778 root = cpuset_refroot(td->td_cpuset); 779 thread_unlock(td); 780 error = cpuset_create(&set, root, &root->cs_mask); 781 cpuset_rel(root); 782 if (error) 783 return (error); 784 error = copyout(&set->cs_id, uap->setid, sizeof(set->cs_id)); 785 if (error == 0) 786 error = cpuset_setproc(-1, set, NULL); 787 cpuset_rel(set); 788 return (error); 789} 790 791#ifndef _SYS_SYSPROTO_H_ 792struct cpuset_setid_args { 793 cpuwhich_t which; 794 id_t id; 795 cpusetid_t setid; 796}; 797#endif 798int 799cpuset_setid(struct thread *td, struct cpuset_setid_args *uap) 800{ 801 struct cpuset *set; 802 int error; 803 804 /* 805 * Presently we only support per-process sets. 806 */ 807 if (uap->which != CPU_WHICH_PID) 808 return (EINVAL); 809 set = cpuset_lookup(uap->setid, td); 810 if (set == NULL) 811 return (ESRCH); 812 error = cpuset_setproc(uap->id, set, NULL); 813 cpuset_rel(set); 814 return (error); 815} 816 817#ifndef _SYS_SYSPROTO_H_ 818struct cpuset_getid_args { 819 cpulevel_t level; 820 cpuwhich_t which; 821 id_t id; 822 cpusetid_t *setid; 823#endif 824int 825cpuset_getid(struct thread *td, struct cpuset_getid_args *uap) 826{ 827 struct cpuset *nset; 828 struct cpuset *set; 829 struct thread *ttd; 830 struct proc *p; 831 cpusetid_t id; 832 int error; 833 834 if (uap->level == CPU_LEVEL_WHICH && uap->which != CPU_WHICH_CPUSET) 835 return (EINVAL); 836 error = cpuset_which(uap->which, uap->id, &p, &ttd, &set); 837 if (error) 838 return (error); 839 switch (uap->which) { 840 case CPU_WHICH_TID: 841 case CPU_WHICH_PID: 842 thread_lock(ttd); 843 set = cpuset_refbase(ttd->td_cpuset); 844 thread_unlock(ttd); 845 PROC_UNLOCK(p); 846 break; 847 case CPU_WHICH_CPUSET: 848 case CPU_WHICH_JAIL: 849 break; 850 case CPU_WHICH_IRQ: 851 return (EINVAL); 852 } 853 switch (uap->level) { 854 case CPU_LEVEL_ROOT: 855 nset = cpuset_refroot(set); 856 cpuset_rel(set); 857 set = nset; 858 break; 859 case CPU_LEVEL_CPUSET: 860 break; 861 case CPU_LEVEL_WHICH: 862 break; 863 } 864 id = set->cs_id; 865 cpuset_rel(set); 866 if (error == 0) 867 error = copyout(&id, uap->setid, sizeof(id)); 868 869 return (error); 870} 871 872#ifndef _SYS_SYSPROTO_H_ 873struct cpuset_getaffinity_args { 874 cpulevel_t level; 875 cpuwhich_t which; 876 id_t id; 877 size_t cpusetsize; 878 cpuset_t *mask; 879}; 880#endif 881int 882cpuset_getaffinity(struct thread *td, struct cpuset_getaffinity_args *uap) 883{ 884 struct thread *ttd; 885 struct cpuset *nset; 886 struct cpuset *set; 887 struct proc *p; 888 cpuset_t *mask; 889 int error; 890 size_t size; 891 892 if (uap->cpusetsize == 0) { 893 td->td_retval[0] = sizeof(cpuset_t); 894 return (0); 895 } 896 if (uap->cpusetsize < sizeof(cpuset_t) || 897 uap->cpusetsize > CPU_MAXSIZE / NBBY) 898 return (ERANGE); 899 size = uap->cpusetsize; 900 mask = malloc(size, M_TEMP, M_WAITOK | M_ZERO); 901 error = cpuset_which(uap->which, uap->id, &p, &ttd, &set); 902 if (error) 903 goto out; 904 switch (uap->level) { 905 case CPU_LEVEL_ROOT: 906 case CPU_LEVEL_CPUSET: 907 switch (uap->which) { 908 case CPU_WHICH_TID: 909 case CPU_WHICH_PID: 910 thread_lock(ttd); 911 set = cpuset_ref(ttd->td_cpuset); 912 thread_unlock(ttd); 913 break; 914 case CPU_WHICH_CPUSET: 915 case CPU_WHICH_JAIL: 916 break; 917 case CPU_WHICH_IRQ: 918 error = EINVAL; 919 goto out; 920 } 921 if (uap->level == CPU_LEVEL_ROOT) 922 nset = cpuset_refroot(set); 923 else 924 nset = cpuset_refbase(set); 925 CPU_COPY(&nset->cs_mask, mask); 926 cpuset_rel(nset); 927 break; 928 case CPU_LEVEL_WHICH: 929 switch (uap->which) { 930 case CPU_WHICH_TID: 931 thread_lock(ttd); 932 CPU_COPY(&ttd->td_cpuset->cs_mask, mask); 933 thread_unlock(ttd); 934 break; 935 case CPU_WHICH_PID: 936 FOREACH_THREAD_IN_PROC(p, ttd) { 937 thread_lock(ttd); 938 CPU_OR(mask, &ttd->td_cpuset->cs_mask); 939 thread_unlock(ttd); 940 } 941 break; 942 case CPU_WHICH_CPUSET: 943 case CPU_WHICH_JAIL: 944 CPU_COPY(&set->cs_mask, mask); 945 break; 946 case CPU_WHICH_IRQ: 947 error = intr_getaffinity(uap->id, mask); 948 break; 949 } 950 break; 951 default: 952 error = EINVAL; 953 break; 954 } 955 if (set) 956 cpuset_rel(set); 957 if (p) 958 PROC_UNLOCK(p); 959 if (error == 0) 960 error = copyout(mask, uap->mask, size); 961out: 962 free(mask, M_TEMP); 963 return (error); 964} 965 966#ifndef _SYS_SYSPROTO_H_ 967struct cpuset_setaffinity_args { 968 cpulevel_t level; 969 cpuwhich_t which; 970 id_t id; 971 size_t cpusetsize; 972 const cpuset_t *mask; 973}; 974#endif 975int 976cpuset_setaffinity(struct thread *td, struct cpuset_setaffinity_args *uap) 977{ 978 struct cpuset *nset; 979 struct cpuset *set; 980 struct thread *ttd; 981 struct proc *p; 982 cpuset_t *mask; 983 int error; 984 985 if (uap->cpusetsize < sizeof(cpuset_t) || 986 uap->cpusetsize > CPU_MAXSIZE / NBBY) 987 return (ERANGE); 988 mask = malloc(uap->cpusetsize, M_TEMP, M_WAITOK | M_ZERO); 989 error = copyin(uap->mask, mask, uap->cpusetsize); 990 if (error) 991 goto out; 992 /* 993 * Verify that no high bits are set. 994 */ 995 if (uap->cpusetsize > sizeof(cpuset_t)) { 996 char *end; 997 char *cp; 998 999 end = cp = (char *)&mask->__bits; 1000 end += uap->cpusetsize; 1001 cp += sizeof(cpuset_t); 1002 while (cp != end) 1003 if (*cp++ != 0) { 1004 error = EINVAL; 1005 goto out; 1006 } 1007 1008 } 1009 switch (uap->level) { 1010 case CPU_LEVEL_ROOT: 1011 case CPU_LEVEL_CPUSET: 1012 error = cpuset_which(uap->which, uap->id, &p, &ttd, &set); 1013 if (error) 1014 break; 1015 switch (uap->which) { 1016 case CPU_WHICH_TID: 1017 case CPU_WHICH_PID: 1018 thread_lock(ttd); 1019 set = cpuset_ref(ttd->td_cpuset); 1020 thread_unlock(ttd); 1021 PROC_UNLOCK(p); 1022 break; 1023 case CPU_WHICH_CPUSET: 1024 case CPU_WHICH_JAIL: 1025 break; 1026 case CPU_WHICH_IRQ: 1027 error = EINVAL; 1028 goto out; 1029 } 1030 if (uap->level == CPU_LEVEL_ROOT) 1031 nset = cpuset_refroot(set); 1032 else 1033 nset = cpuset_refbase(set); 1034 error = cpuset_modify(nset, mask); 1035 cpuset_rel(nset); 1036 cpuset_rel(set); 1037 break; 1038 case CPU_LEVEL_WHICH: 1039 switch (uap->which) { 1040 case CPU_WHICH_TID: 1041 error = cpuset_setthread(uap->id, mask); 1042 break; 1043 case CPU_WHICH_PID: 1044 error = cpuset_setproc(uap->id, NULL, mask); 1045 break; 1046 case CPU_WHICH_CPUSET: 1047 case CPU_WHICH_JAIL: 1048 error = cpuset_which(uap->which, uap->id, &p, 1049 &ttd, &set); 1050 if (error == 0) { 1051 error = cpuset_modify(set, mask); 1052 cpuset_rel(set); 1053 } 1054 break; 1055 case CPU_WHICH_IRQ: 1056 error = intr_setaffinity(uap->id, mask); 1057 break; 1058 default: 1059 error = EINVAL; 1060 break; 1061 } 1062 break; 1063 default: 1064 error = EINVAL; 1065 break; 1066 } 1067out: 1068 free(mask, M_TEMP); 1069 return (error); 1070} 1071 1072#ifdef DDB 1073DB_SHOW_COMMAND(cpusets, db_show_cpusets) 1074{ 1075 struct cpuset *set; 1076 int cpu, once; 1077 1078 LIST_FOREACH(set, &cpuset_ids, cs_link) { 1079 db_printf("set=%p id=%-6u ref=%-6d flags=0x%04x parent id=%d\n", 1080 set, set->cs_id, set->cs_ref, set->cs_flags, 1081 (set->cs_parent != NULL) ? set->cs_parent->cs_id : 0); 1082 db_printf(" mask="); 1083 for (once = 0, cpu = 0; cpu < CPU_SETSIZE; cpu++) { 1084 if (CPU_ISSET(cpu, &set->cs_mask)) { 1085 if (once == 0) { 1086 db_printf("%d", cpu); 1087 once = 1; 1088 } else 1089 db_printf(",%d", cpu); 1090 } 1091 } 1092 db_printf("\n"); 1093 if (db_pager_quit) 1094 break; 1095 } 1096} 1097#endif /* DDB */ 1098