1139804Simp/*- 248391Speter * Copyright (c) 1999 Peter Wemm <peter@FreeBSD.org> 348391Speter * All rights reserved. 448391Speter * 548391Speter * Redistribution and use in source and binary forms, with or without 648391Speter * modification, are permitted provided that the following conditions 748391Speter * are met: 848391Speter * 1. Redistributions of source code must retain the above copyright 948391Speter * notice, this list of conditions and the following disclaimer. 1048391Speter * 2. Redistributions in binary form must reproduce the above copyright 1148391Speter * notice, this list of conditions and the following disclaimer in the 1248391Speter * documentation and/or other materials provided with the distribution. 1348391Speter * 1448391Speter * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 1548391Speter * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1648391Speter * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 1748391Speter * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 1848391Speter * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 1948391Speter * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2048391Speter * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2148391Speter * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2248391Speter * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2348391Speter * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2448391Speter * SUCH DAMAGE. 2548391Speter */ 2648391Speter 27116182Sobrien#include <sys/cdefs.h> 28116182Sobrien__FBSDID("$FreeBSD$"); 29116182Sobrien 3048391Speter#include <sys/param.h> 3148391Speter#include <sys/systm.h> 32230984Srstone#include <sys/cpuset.h> 3348391Speter#include <sys/kthread.h> 3470317Sjake#include <sys/lock.h> 3574927Sjhb#include <sys/mutex.h> 3674927Sjhb#include <sys/proc.h> 3755722Simp#include <sys/resourcevar.h> 38214238Sdavidxu#include <sys/rwlock.h> 3955539Sluoqi#include <sys/signalvar.h> 4074927Sjhb#include <sys/sx.h> 4148391Speter#include <sys/unistd.h> 4248391Speter#include <sys/wait.h> 43166188Sjeff#include <sys/sched.h> 44173004Sjulian#include <vm/vm.h> 45173004Sjulian#include <vm/vm_extern.h> 4648391Speter 4748391Speter#include <machine/stdarg.h> 4848391Speter 4948391Speter/* 5048391Speter * Start a kernel process. This is called after a fork() call in 5148391Speter * mi_startup() in the file kern/init_main.c. 5248391Speter * 5348391Speter * This function is used to start "internal" daemons and intended 5448391Speter * to be called from SYSINIT(). 5548391Speter */ 5648391Spetervoid 5748391Speterkproc_start(udata) 5848391Speter const void *udata; 5948391Speter{ 6048391Speter const struct kproc_desc *kp = udata; 6148391Speter int error; 6248391Speter 63172836Sjulian error = kproc_create((void (*)(void *))kp->func, NULL, 64104354Sscottl kp->global_procpp, 0, 0, "%s", kp->arg0); 6548391Speter if (error) 6648391Speter panic("kproc_start: %s: error %d", kp->arg0, error); 6748391Speter} 6848391Speter 6948391Speter/* 7065557Sjasone * Create a kernel process/thread/whatever. It shares its address space 7148391Speter * with proc0 - ie: kernel only. 7265557Sjasone * 7365557Sjasone * func is the function to start. 7465557Sjasone * arg is the parameter to pass to function on first startup. 7565557Sjasone * newpp is the return value pointing to the thread's struct proc. 7665557Sjasone * flags are flags to fork1 (in unistd.h) 7765557Sjasone * fmt and following will be *printf'd into (*newpp)->p_comm (for ps, etc.). 7848391Speter */ 7948391Speterint 80172836Sjuliankproc_create(void (*func)(void *), void *arg, 81104354Sscottl struct proc **newpp, int flags, int pages, const char *fmt, ...) 8248391Speter{ 8348391Speter int error; 8448391Speter va_list ap; 85103216Sjulian struct thread *td; 8648391Speter struct proc *p2; 8748391Speter 88114434Sdes if (!proc0.p_stats) 89172836Sjulian panic("kproc_create called too soon"); 9065557Sjasone 9190375Speter error = fork1(&thread0, RFMEM | RFFDG | RFPROC | RFSTOPPED | flags, 92224987Sjonathan pages, &p2, NULL, 0); 9348391Speter if (error) 9448391Speter return error; 9548391Speter 9648391Speter /* save a global descriptor, if desired */ 9748391Speter if (newpp != NULL) 9848391Speter *newpp = p2; 9948391Speter 10048391Speter /* this is a non-swapped system process */ 10171559Sjhb PROC_LOCK(p2); 102173004Sjulian td = FIRST_THREAD_IN_PROC(p2); 10371559Sjhb p2->p_flag |= P_SYSTEM | P_KTHREAD; 104173004Sjulian td->td_pflags |= TDP_KTHREAD; 105114983Sjhb mtx_lock(&p2->p_sigacts->ps_mtx); 106114983Sjhb p2->p_sigacts->ps_flag |= PS_NOCLDWAIT; 107114983Sjhb mtx_unlock(&p2->p_sigacts->ps_mtx); 10871559Sjhb PROC_UNLOCK(p2); 10948391Speter 11048391Speter /* set up arg0 for 'ps', et al */ 11148391Speter va_start(ap, fmt); 11248391Speter vsnprintf(p2->p_comm, sizeof(p2->p_comm), fmt, ap); 11348391Speter va_end(ap); 114173004Sjulian /* set up arg0 for 'ps', et al */ 115173004Sjulian va_start(ap, fmt); 116173004Sjulian vsnprintf(td->td_name, sizeof(td->td_name), fmt, ap); 117173004Sjulian va_end(ap); 118232700Sjhb#ifdef KTR 119232700Sjhb sched_clear_tdname(td); 120232700Sjhb#endif 12148391Speter 12248391Speter /* call the processes' main()... */ 123103216Sjulian cpu_set_fork_handler(td, func, arg); 124230984Srstone 125230984Srstone /* Avoid inheriting affinity from a random parent. */ 126230984Srstone cpuset_setthread(td->td_tid, cpuset_root); 127217079Sjhb thread_lock(td); 128103216Sjulian TD_SET_CAN_RUN(td); 129217079Sjhb sched_prio(td, PVM); 130217079Sjhb sched_user_prio(td, PUSER); 13148391Speter 13269657Sjhb /* Delay putting it on the run queue until now. */ 133217079Sjhb if (!(flags & RFSTOPPED)) 134166188Sjeff sched_add(td, SRQ_BORING); 135217079Sjhb thread_unlock(td); 13669657Sjhb 13748391Speter return 0; 13848391Speter} 13948391Speter 14048391Spetervoid 141172836Sjuliankproc_exit(int ecode) 14248391Speter{ 14386293Speter struct thread *td; 14486293Speter struct proc *p; 14570317Sjake 14686293Speter td = curthread; 14786293Speter p = td->td_proc; 148155400Sjhb 149155400Sjhb /* 150155400Sjhb * Reparent curthread from proc0 to init so that the zombie 151155400Sjhb * is harvested. 152155400Sjhb */ 15374927Sjhb sx_xlock(&proctree_lock); 15486292Sdillon PROC_LOCK(p); 15586292Sdillon proc_reparent(p, initproc); 15686292Sdillon PROC_UNLOCK(p); 15774927Sjhb sx_xunlock(&proctree_lock); 158155400Sjhb 159155400Sjhb /* 160155400Sjhb * Wakeup anyone waiting for us to exit. 161155400Sjhb */ 162155400Sjhb wakeup(p); 163155400Sjhb 164155400Sjhb /* Buh-bye! */ 16586293Speter exit1(td, W_EXITCODE(ecode, 0)); 16648391Speter} 16748391Speter 16855539Sluoqi/* 16955539Sluoqi * Advise a kernel process to suspend (or resume) in its main loop. 17055539Sluoqi * Participation is voluntary. 17155539Sluoqi */ 17255539Sluoqiint 173172836Sjuliankproc_suspend(struct proc *p, int timo) 17455539Sluoqi{ 17555539Sluoqi /* 17655539Sluoqi * Make sure this is indeed a system process and we can safely 177104306Sjmallett * use the p_siglist field. 17855539Sluoqi */ 17973911Sjhb PROC_LOCK(p); 18073911Sjhb if ((p->p_flag & P_KTHREAD) == 0) { 18173911Sjhb PROC_UNLOCK(p); 18255539Sluoqi return (EINVAL); 18373911Sjhb } 184104306Sjmallett SIGADDSET(p->p_siglist, SIGSTOP); 18588160Speter wakeup(p); 186173004Sjulian return msleep(&p->p_siglist, &p->p_mtx, PPAUSE | PDROP, "suspkp", timo); 18755539Sluoqi} 18855539Sluoqi 18955539Sluoqiint 190172836Sjuliankproc_resume(struct proc *p) 19155539Sluoqi{ 19255539Sluoqi /* 19355539Sluoqi * Make sure this is indeed a system process and we can safely 19455539Sluoqi * use the p_siglist field. 19555539Sluoqi */ 19673911Sjhb PROC_LOCK(p); 19773911Sjhb if ((p->p_flag & P_KTHREAD) == 0) { 19873911Sjhb PROC_UNLOCK(p); 19955539Sluoqi return (EINVAL); 20073911Sjhb } 201104306Sjmallett SIGDELSET(p->p_siglist, SIGSTOP); 20273911Sjhb PROC_UNLOCK(p); 203104306Sjmallett wakeup(&p->p_siglist); 20455539Sluoqi return (0); 20555539Sluoqi} 20655539Sluoqi 20755539Sluoqivoid 208172836Sjuliankproc_suspend_check(struct proc *p) 20955539Sluoqi{ 21073911Sjhb PROC_LOCK(p); 211104306Sjmallett while (SIGISMEMBER(p->p_siglist, SIGSTOP)) { 212104306Sjmallett wakeup(&p->p_siglist); 213173004Sjulian msleep(&p->p_siglist, &p->p_mtx, PPAUSE, "kpsusp", 0); 21455539Sluoqi } 21573911Sjhb PROC_UNLOCK(p); 21655539Sluoqi} 217173004Sjulian 218173004Sjulian 219173004Sjulian/* 220173004Sjulian * Start a kernel thread. 221173004Sjulian * 222173004Sjulian * This function is used to start "internal" daemons and intended 223173004Sjulian * to be called from SYSINIT(). 224173004Sjulian */ 225173004Sjulian 226173004Sjulianvoid 227173004Sjuliankthread_start(udata) 228173004Sjulian const void *udata; 229173004Sjulian{ 230173004Sjulian const struct kthread_desc *kp = udata; 231173004Sjulian int error; 232173004Sjulian 233173004Sjulian error = kthread_add((void (*)(void *))kp->func, NULL, 234173004Sjulian NULL, kp->global_threadpp, 0, 0, "%s", kp->arg0); 235173004Sjulian if (error) 236173004Sjulian panic("kthread_start: %s: error %d", kp->arg0, error); 237173004Sjulian} 238173004Sjulian 239173004Sjulian/* 240173004Sjulian * Create a kernel thread. It shares its address space 241173004Sjulian * with proc0 - ie: kernel only. 242173004Sjulian * 243173004Sjulian * func is the function to start. 244173004Sjulian * arg is the parameter to pass to function on first startup. 245173004Sjulian * newtdp is the return value pointing to the thread's struct thread. 246173004Sjulian * ** XXX fix this --> flags are flags to fork1 (in unistd.h) 247173004Sjulian * fmt and following will be *printf'd into (*newtd)->td_name (for ps, etc.). 248173004Sjulian */ 249173004Sjulianint 250173004Sjuliankthread_add(void (*func)(void *), void *arg, struct proc *p, 251173004Sjulian struct thread **newtdp, int flags, int pages, const char *fmt, ...) 252173004Sjulian{ 253173004Sjulian va_list ap; 254173004Sjulian struct thread *newtd, *oldtd; 255173004Sjulian 256173004Sjulian if (!proc0.p_stats) 257173004Sjulian panic("kthread_add called too soon"); 258173004Sjulian 259173052Sjulian /* If no process supplied, put it on proc0 */ 260254457Sbryanv if (p == NULL) 261173004Sjulian p = &proc0; 262173004Sjulian 263173052Sjulian /* Initialize our new td */ 264196730Skib newtd = thread_alloc(pages); 265173004Sjulian if (newtd == NULL) 266173004Sjulian return (ENOMEM); 267173004Sjulian 268254457Sbryanv PROC_LOCK(p); 269254457Sbryanv oldtd = FIRST_THREAD_IN_PROC(p); 270254457Sbryanv 271173004Sjulian bzero(&newtd->td_startzero, 272173004Sjulian __rangeof(struct thread, td_startzero, td_endzero)); 273173004Sjulian bcopy(&oldtd->td_startcopy, &newtd->td_startcopy, 274173004Sjulian __rangeof(struct thread, td_startcopy, td_endcopy)); 275173004Sjulian 276173004Sjulian /* set up arg0 for 'ps', et al */ 277173004Sjulian va_start(ap, fmt); 278173004Sjulian vsnprintf(newtd->td_name, sizeof(newtd->td_name), fmt, ap); 279173004Sjulian va_end(ap); 280173004Sjulian 281173004Sjulian newtd->td_proc = p; /* needed for cpu_set_upcall */ 282173004Sjulian 283173004Sjulian /* XXX optimise this probably? */ 284173004Sjulian /* On x86 (and probably the others too) it is way too full of junk */ 285173004Sjulian /* Needs a better name */ 286173004Sjulian cpu_set_upcall(newtd, oldtd); 287173004Sjulian /* put the designated function(arg) as the resume context */ 288173004Sjulian cpu_set_fork_handler(newtd, func, arg); 289173004Sjulian 290173004Sjulian newtd->td_pflags |= TDP_KTHREAD; 291173004Sjulian newtd->td_ucred = crhold(p->p_ucred); 292173004Sjulian 293173004Sjulian /* this code almost the same as create_thread() in kern_thr.c */ 294173004Sjulian p->p_flag |= P_HADTHREADS; 295173004Sjulian thread_link(newtd, p); 296173004Sjulian thread_lock(oldtd); 297173004Sjulian /* let the scheduler know about these things. */ 298173004Sjulian sched_fork_thread(oldtd, newtd); 299173004Sjulian TD_SET_CAN_RUN(newtd); 300173004Sjulian thread_unlock(oldtd); 301173004Sjulian PROC_UNLOCK(p); 302173004Sjulian 303213642Sdavidxu tidhash_add(newtd); 304173004Sjulian 305230984Srstone /* Avoid inheriting affinity from a random parent. */ 306230984Srstone cpuset_setthread(newtd->td_tid, cpuset_root); 307230984Srstone 308173004Sjulian /* Delay putting it on the run queue until now. */ 309173004Sjulian if (!(flags & RFSTOPPED)) { 310173004Sjulian thread_lock(newtd); 311173004Sjulian sched_add(newtd, SRQ_BORING); 312173004Sjulian thread_unlock(newtd); 313173004Sjulian } 314173004Sjulian if (newtdp) 315173004Sjulian *newtdp = newtd; 316173004Sjulian return 0; 317173004Sjulian} 318173004Sjulian 319173004Sjulianvoid 320173031Sjuliankthread_exit(void) 321173004Sjulian{ 322173658Sjhb struct proc *p; 323173658Sjhb 324204087Sattilio p = curthread->td_proc; 325204087Sattilio 326173658Sjhb /* A module may be waiting for us to exit. */ 327173052Sjulian wakeup(curthread); 328216921Sjhb 329216921Sjhb /* 330216921Sjhb * The last exiting thread in a kernel process must tear down 331216921Sjhb * the whole process. 332216921Sjhb */ 333214238Sdavidxu rw_wlock(&tidhash_lock); 334204087Sattilio PROC_LOCK(p); 335204089Sattilio if (p->p_numthreads == 1) { 336204087Sattilio PROC_UNLOCK(p); 337214238Sdavidxu rw_wunlock(&tidhash_lock); 338204087Sattilio kproc_exit(0); 339204087Sattilio } 340214238Sdavidxu LIST_REMOVE(curthread, td_hash); 341214238Sdavidxu rw_wunlock(&tidhash_lock); 342173658Sjhb PROC_SLOCK(p); 343173004Sjulian thread_exit(); 344173004Sjulian} 345173004Sjulian 346173004Sjulian/* 347173004Sjulian * Advise a kernel process to suspend (or resume) in its main loop. 348173004Sjulian * Participation is voluntary. 349173004Sjulian */ 350173004Sjulianint 351173004Sjuliankthread_suspend(struct thread *td, int timo) 352173004Sjulian{ 353202933Sattilio struct proc *p; 354202933Sattilio 355202933Sattilio p = td->td_proc; 356202933Sattilio 357202933Sattilio /* 358204088Sattilio * td_pflags should not be read by any thread other than 359202933Sattilio * curthread, but as long as this flag is invariant during the 360204088Sattilio * thread's lifetime, it is OK to check its state. 361202933Sattilio */ 362202933Sattilio if ((td->td_pflags & TDP_KTHREAD) == 0) 363173004Sjulian return (EINVAL); 364202933Sattilio 365202933Sattilio /* 366202933Sattilio * The caller of the primitive should have already checked that the 367202933Sattilio * thread is up and running, thus not being blocked by other 368202933Sattilio * conditions. 369202933Sattilio */ 370202933Sattilio PROC_LOCK(p); 371173004Sjulian thread_lock(td); 372173004Sjulian td->td_flags |= TDF_KTH_SUSP; 373173004Sjulian thread_unlock(td); 374202933Sattilio return (msleep(&td->td_flags, &p->p_mtx, PPAUSE | PDROP, "suspkt", 375202933Sattilio timo)); 376173004Sjulian} 377173004Sjulian 378173004Sjulian/* 379202933Sattilio * Resume a thread previously put asleep with kthread_suspend(). 380173004Sjulian */ 381173004Sjulianint 382173004Sjuliankthread_resume(struct thread *td) 383173004Sjulian{ 384202933Sattilio struct proc *p; 385202933Sattilio 386202933Sattilio p = td->td_proc; 387202933Sattilio 388202933Sattilio /* 389204088Sattilio * td_pflags should not be read by any thread other than 390202933Sattilio * curthread, but as long as this flag is invariant during the 391204088Sattilio * thread's lifetime, it is OK to check its state. 392202933Sattilio */ 393202933Sattilio if ((td->td_pflags & TDP_KTHREAD) == 0) 394173004Sjulian return (EINVAL); 395202933Sattilio 396202933Sattilio PROC_LOCK(p); 397173004Sjulian thread_lock(td); 398173004Sjulian td->td_flags &= ~TDF_KTH_SUSP; 399173004Sjulian thread_unlock(td); 400202933Sattilio wakeup(&td->td_flags); 401202933Sattilio PROC_UNLOCK(p); 402173004Sjulian return (0); 403173004Sjulian} 404173004Sjulian 405173004Sjulian/* 406173004Sjulian * Used by the thread to poll as to whether it should yield/sleep 407173004Sjulian * and notify the caller that is has happened. 408173004Sjulian */ 409173004Sjulianvoid 410202933Sattiliokthread_suspend_check() 411173004Sjulian{ 412202933Sattilio struct proc *p; 413202933Sattilio struct thread *td; 414202933Sattilio 415202933Sattilio td = curthread; 416202933Sattilio p = td->td_proc; 417202933Sattilio 418202933Sattilio if ((td->td_pflags & TDP_KTHREAD) == 0) 419202933Sattilio panic("%s: curthread is not a valid kthread", __func__); 420202933Sattilio 421202933Sattilio /* 422202933Sattilio * As long as the double-lock protection is used when accessing the 423202933Sattilio * TDF_KTH_SUSP flag, synchronizing the read operation via proc mutex 424202933Sattilio * is fine. 425202933Sattilio */ 426202933Sattilio PROC_LOCK(p); 427173004Sjulian while (td->td_flags & TDF_KTH_SUSP) { 428173004Sjulian wakeup(&td->td_flags); 429202933Sattilio msleep(&td->td_flags, &p->p_mtx, PPAUSE, "ktsusp", 0); 430173004Sjulian } 431202933Sattilio PROC_UNLOCK(p); 432173004Sjulian} 433173004Sjulian 434173004Sjulianint 435173004Sjuliankproc_kthread_add(void (*func)(void *), void *arg, 436173004Sjulian struct proc **procptr, struct thread **tdptr, 437208390Sjhb int flags, int pages, const char *procname, const char *fmt, ...) 438173004Sjulian{ 439173004Sjulian int error; 440173004Sjulian va_list ap; 441173004Sjulian char buf[100]; 442173004Sjulian struct thread *td; 443173004Sjulian 444173004Sjulian if (*procptr == 0) { 445173004Sjulian error = kproc_create(func, arg, 446173004Sjulian procptr, flags, pages, "%s", procname); 447173004Sjulian if (error) 448173004Sjulian return (error); 449173004Sjulian td = FIRST_THREAD_IN_PROC(*procptr); 450178682Sjulian if (tdptr) 451178682Sjulian *tdptr = td; 452173004Sjulian va_start(ap, fmt); 453173004Sjulian vsnprintf(td->td_name, sizeof(td->td_name), fmt, ap); 454173004Sjulian va_end(ap); 455232700Sjhb#ifdef KTR 456232700Sjhb sched_clear_tdname(td); 457232700Sjhb#endif 458173004Sjulian return (0); 459173004Sjulian } 460173004Sjulian va_start(ap, fmt); 461173004Sjulian vsnprintf(buf, sizeof(buf), fmt, ap); 462173004Sjulian va_end(ap); 463173004Sjulian error = kthread_add(func, arg, *procptr, 464173004Sjulian tdptr, flags, pages, "%s", buf); 465173004Sjulian return (error); 466173004Sjulian} 467