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31 * @(#)kern_proc.c 8.7 (Berkeley) 2/14/95
32 * $FreeBSD: src/sys/kern/kern_proc.c,v 1.63.2.9 2003/05/08 07:47:16 kbyanc Exp $
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/sysctl.h>
39 #include <sys/malloc.h>
41 #include <sys/vnode.h>
43 #include <sys/filedesc.h>
45 #include <sys/dsched.h>
46 #include <sys/signalvar.h>
47 #include <sys/spinlock.h>
51 #include <vm/vm_map.h>
53 #include <machine/smp.h>
55 #include <sys/refcount.h>
56 #include <sys/spinlock2.h>
57 #include <sys/mplock2.h>
59 static MALLOC_DEFINE(M_PGRP, "pgrp", "process group header");
60 MALLOC_DEFINE(M_SESSION, "session", "session header");
61 MALLOC_DEFINE(M_PROC, "proc", "Proc structures");
62 MALLOC_DEFINE(M_LWP, "lwp", "lwp structures");
63 MALLOC_DEFINE(M_SUBPROC, "subproc", "Proc sub-structures");
65 int ps_showallprocs = 1;
66 static int ps_showallthreads = 1;
67 SYSCTL_INT(_security, OID_AUTO, ps_showallprocs, CTLFLAG_RW,
69 "Unprivileged processes can see processes with different UID/GID");
70 SYSCTL_INT(_security, OID_AUTO, ps_showallthreads, CTLFLAG_RW,
71 &ps_showallthreads, 0,
72 "Unprivileged processes can see kernel threads");
74 static void orphanpg(struct pgrp *pg);
75 static pid_t proc_getnewpid_locked(int random_offset);
80 struct pidhashhead *pidhashtbl;
82 struct pgrphashhead *pgrphashtbl;
84 struct proclist allproc;
85 struct proclist zombproc;
86 struct spinlock pghash_spin = SPINLOCK_INITIALIZER(&pghash_spin);
89 * Random component to nextpid generation. We mix in a random factor to make
90 * it a little harder to predict. We sanity check the modulus value to avoid
91 * doing it in critical paths. Don't let it be too small or we pointlessly
92 * waste randomness entropy, and don't let it be impossibly large. Using a
93 * modulus that is too big causes a LOT more process table scans and slows
94 * down fork processing as the pidchecked caching is defeated.
96 static int randompid = 0;
102 sysctl_kern_randompid(SYSCTL_HANDLER_ARGS)
107 error = sysctl_handle_int(oidp, &pid, 0, req);
108 if (error || !req->newptr)
110 if (pid < 0 || pid > PID_MAX - 100) /* out of range */
112 else if (pid < 2) /* NOP */
114 else if (pid < 100) /* Make it reasonable */
120 SYSCTL_PROC(_kern, OID_AUTO, randompid, CTLTYPE_INT|CTLFLAG_RW,
121 0, 0, sysctl_kern_randompid, "I", "Random PID modulus");
124 * Initialize global process hashing structures.
126 * Called from the low level boot code only.
132 LIST_INIT(&zombproc);
134 pidhashtbl = hashinit(maxproc / 4, M_PROC, &pidhash);
135 pgrphashtbl = hashinit(maxproc / 4, M_PROC, &pgrphash);
140 * Process hold/release support functions. These functions must be MPSAFE.
141 * Called via the PHOLD(), PRELE(), and PSTALL() macros.
143 * p->p_lock is a simple hold count with a waiting interlock. No wakeup()
144 * is issued unless someone is actually waiting for the process.
146 * Most holds are short-term, allowing a process scan or other similar
147 * operation to access a proc structure without it getting ripped out from
148 * under us. procfs and process-list sysctl ops also use the hold function
149 * interlocked with various p_flags to keep the vmspace intact when reading
150 * or writing a user process's address space.
152 * There are two situations where a hold count can be longer. Exiting lwps
153 * hold the process until the lwp is reaped, and the parent will hold the
154 * child during vfork()/exec() sequences while the child is marked P_PPWAIT.
156 * The kernel waits for the hold count to drop to 0 (or 1 in some cases) at
157 * various critical points in the fork/exec and exit paths before proceeding.
159 #define PLOCK_ZOMB 0x20000000
160 #define PLOCK_WAITING 0x40000000
161 #define PLOCK_MASK 0x1FFFFFFF
164 pstall(struct proc *p, const char *wmesg, int count)
172 if ((o & PLOCK_MASK) <= count)
174 n = o | PLOCK_WAITING;
175 tsleep_interlock(&p->p_lock, 0);
178 * If someone is trying to single-step the process during
179 * an exec or an exit they can deadlock us because procfs
180 * sleeps with the process held.
183 if (p->p_flags & P_INEXEC) {
185 } else if (p->p_flags & P_POSTEXIT) {
186 spin_lock(&p->p_spin);
189 spin_unlock(&p->p_spin);
194 if (atomic_cmpset_int(&p->p_lock, o, n)) {
195 tsleep(&p->p_lock, PINTERLOCKED, wmesg, 0);
201 phold(struct proc *p)
203 atomic_add_int(&p->p_lock, 1);
207 * WARNING! On last release (p) can become instantly invalid due to
211 prele(struct proc *p)
219 if (atomic_cmpset_int(&p->p_lock, 1, 0))
227 KKASSERT((o & PLOCK_MASK) > 0);
229 n = (o - 1) & ~PLOCK_WAITING;
230 if (atomic_cmpset_int(&p->p_lock, o, n)) {
231 if (o & PLOCK_WAITING)
239 * Hold and flag serialized for zombie reaping purposes.
241 * This function will fail if it has to block, returning non-zero with
242 * neither the flag set or the hold count bumped. Note that we must block
243 * without holding a ref, meaning that the caller must ensure that (p)
244 * remains valid through some other interlock (typically on its parent
245 * process's p_token).
247 * Zero is returned on success. The hold count will be incremented and
248 * the serialization flag acquired. Note that serialization is only against
249 * other pholdzomb() calls, not against phold() calls.
252 pholdzomb(struct proc *p)
260 if (atomic_cmpset_int(&p->p_lock, 0, PLOCK_ZOMB | 1))
269 if ((o & PLOCK_ZOMB) == 0) {
270 n = (o + 1) | PLOCK_ZOMB;
271 if (atomic_cmpset_int(&p->p_lock, o, n))
274 KKASSERT((o & PLOCK_MASK) > 0);
275 n = o | PLOCK_WAITING;
276 tsleep_interlock(&p->p_lock, 0);
277 if (atomic_cmpset_int(&p->p_lock, o, n)) {
278 tsleep(&p->p_lock, PINTERLOCKED, "phldz", 0);
279 /* (p) can be ripped out at this point */
287 * Release PLOCK_ZOMB and the hold count, waking up any waiters.
289 * WARNING! On last release (p) can become instantly invalid due to
293 prelezomb(struct proc *p)
301 if (atomic_cmpset_int(&p->p_lock, PLOCK_ZOMB | 1, 0))
307 KKASSERT(p->p_lock & PLOCK_ZOMB);
310 KKASSERT((o & PLOCK_MASK) > 0);
312 n = (o - 1) & ~(PLOCK_ZOMB | PLOCK_WAITING);
313 if (atomic_cmpset_int(&p->p_lock, o, n)) {
314 if (o & PLOCK_WAITING)
322 * Is p an inferior of the current process?
325 * The caller must hold proc_token if the caller wishes a stable result.
328 inferior(struct proc *p)
330 lwkt_gettoken(&proc_token);
331 while (p != curproc) {
333 lwkt_reltoken(&proc_token);
338 lwkt_reltoken(&proc_token);
343 * Locate a process by number. The returned process will be referenced and
344 * must be released with PRELE().
351 struct proc *p = curproc;
354 * Shortcut the current process
356 if (p && p->p_pid == pid) {
362 * Otherwise find it in the hash table.
364 lwkt_gettoken(&proc_token);
365 LIST_FOREACH(p, PIDHASH(pid), p_hash) {
366 if (p->p_pid == pid) {
368 lwkt_reltoken(&proc_token);
372 lwkt_reltoken(&proc_token);
378 * Locate a process by number. The returned process is NOT referenced.
379 * The caller should hold proc_token if the caller wishes a stable result.
386 struct proc *p = curproc;
389 * Shortcut the current process
391 if (p && p->p_pid == pid)
394 lwkt_gettoken(&proc_token);
395 LIST_FOREACH(p, PIDHASH(pid), p_hash) {
396 if (p->p_pid == pid) {
397 lwkt_reltoken(&proc_token);
401 lwkt_reltoken(&proc_token);
406 pgref(struct pgrp *pgrp)
408 refcount_acquire(&pgrp->pg_refs);
412 pgrel(struct pgrp *pgrp)
417 count = pgrp->pg_refs;
421 spin_lock(&pghash_spin);
422 if (atomic_cmpset_int(&pgrp->pg_refs, 1, 0))
424 spin_unlock(&pghash_spin);
427 if (atomic_cmpset_int(&pgrp->pg_refs, count, count - 1))
434 * Successful 1->0 transition, pghash_spin is held.
436 LIST_REMOVE(pgrp, pg_hash);
437 spin_unlock(&pghash_spin);
440 * Reset any sigio structures pointing to us as a result of
441 * F_SETOWN with our pgid.
443 funsetownlst(&pgrp->pg_sigiolst);
445 if (pgrp->pg_session->s_ttyp != NULL &&
446 pgrp->pg_session->s_ttyp->t_pgrp == pgrp) {
447 pgrp->pg_session->s_ttyp->t_pgrp = NULL;
449 sess_rele(pgrp->pg_session);
454 * Locate a process group by number. The returned process group will be
455 * referenced w/pgref() and must be released with pgrel() (or assigned
456 * somewhere if you wish to keep the reference).
465 spin_lock_shared(&pghash_spin);
466 LIST_FOREACH(pgrp, PGRPHASH(pgid), pg_hash) {
467 if (pgrp->pg_id == pgid) {
468 refcount_acquire(&pgrp->pg_refs);
469 spin_unlock_shared(&pghash_spin);
473 spin_unlock_shared(&pghash_spin);
478 * Move p to a new or existing process group (and session)
483 enterpgrp(struct proc *p, pid_t pgid, int mksess)
491 KASSERT(pgrp == NULL || !mksess,
492 ("enterpgrp: setsid into non-empty pgrp"));
493 KASSERT(!SESS_LEADER(p),
494 ("enterpgrp: session leader attempted setpgrp"));
497 pid_t savepid = p->p_pid;
502 KASSERT(p->p_pid == pgid,
503 ("enterpgrp: new pgrp and pid != pgid"));
504 if ((np = pfindn(savepid)) == NULL || np != p) {
508 pgrp = kmalloc(sizeof(struct pgrp), M_PGRP, M_WAITOK);
510 struct session *sess;
515 sess = kmalloc(sizeof(struct session), M_SESSION,
518 sess->s_sid = p->p_pid;
520 sess->s_ttyvp = NULL;
522 bcopy(p->p_session->s_login, sess->s_login,
523 sizeof(sess->s_login));
524 pgrp->pg_session = sess;
525 KASSERT(p == curproc,
526 ("enterpgrp: mksession and p != curproc"));
527 lwkt_gettoken(&p->p_token);
528 p->p_flags &= ~P_CONTROLT;
529 lwkt_reltoken(&p->p_token);
531 pgrp->pg_session = p->p_session;
532 sess_hold(pgrp->pg_session);
535 LIST_INIT(&pgrp->pg_members);
537 SLIST_INIT(&pgrp->pg_sigiolst);
538 lwkt_token_init(&pgrp->pg_token, "pgrp_token");
539 refcount_init(&pgrp->pg_refs, 1);
540 lockinit(&pgrp->pg_lock, "pgwt", 0, 0);
541 spin_lock(&pghash_spin);
542 LIST_INSERT_HEAD(PGRPHASH(pgid), pgrp, pg_hash);
543 spin_unlock(&pghash_spin);
544 } else if (pgrp == p->p_pgrp) {
547 } /* else pgfind() referenced the pgrp */
549 lwkt_gettoken(&pgrp->pg_token);
550 lwkt_gettoken(&p->p_token);
553 * Replace p->p_pgrp, handling any races that occur.
555 while ((opgrp = p->p_pgrp) != NULL) {
557 lwkt_gettoken(&opgrp->pg_token);
558 if (opgrp != p->p_pgrp) {
559 lwkt_reltoken(&opgrp->pg_token);
563 LIST_REMOVE(p, p_pglist);
567 LIST_INSERT_HEAD(&pgrp->pg_members, p, p_pglist);
570 * Adjust eligibility of affected pgrps to participate in job control.
571 * Increment eligibility counts before decrementing, otherwise we
572 * could reach 0 spuriously during the first call.
576 fixjobc(p, opgrp, 0);
577 lwkt_reltoken(&opgrp->pg_token);
578 pgrel(opgrp); /* manual pgref */
579 pgrel(opgrp); /* p->p_pgrp ref */
581 lwkt_reltoken(&p->p_token);
582 lwkt_reltoken(&pgrp->pg_token);
590 * Remove process from process group
595 leavepgrp(struct proc *p)
597 struct pgrp *pg = p->p_pgrp;
599 lwkt_gettoken(&p->p_token);
600 while ((pg = p->p_pgrp) != NULL) {
602 lwkt_gettoken(&pg->pg_token);
603 if (p->p_pgrp != pg) {
604 lwkt_reltoken(&pg->pg_token);
609 LIST_REMOVE(p, p_pglist);
610 lwkt_reltoken(&pg->pg_token);
611 pgrel(pg); /* manual pgref */
612 pgrel(pg); /* p->p_pgrp ref */
615 lwkt_reltoken(&p->p_token);
621 * Adjust the ref count on a session structure. When the ref count falls to
622 * zero the tty is disassociated from the session and the session structure
623 * is freed. Note that tty assocation is not itself ref-counted.
628 sess_hold(struct session *sp)
630 atomic_add_int(&sp->s_count, 1);
637 sess_rele(struct session *sp)
647 lwkt_gettoken(&tty_token);
648 if (atomic_cmpset_int(&sp->s_count, 1, 0))
650 lwkt_reltoken(&tty_token);
653 if (atomic_cmpset_int(&sp->s_count, count, count - 1))
660 * Successful 1->0 transition and tty_token is held.
662 if (sp->s_ttyp && sp->s_ttyp->t_session) {
663 #ifdef TTY_DO_FULL_CLOSE
664 /* FULL CLOSE, see ttyclearsession() */
665 KKASSERT(sp->s_ttyp->t_session == sp);
666 sp->s_ttyp->t_session = NULL;
668 /* HALF CLOSE, see ttyclearsession() */
669 if (sp->s_ttyp->t_session == sp)
670 sp->s_ttyp->t_session = NULL;
673 if ((tp = sp->s_ttyp) != NULL) {
677 kfree(sp, M_SESSION);
678 lwkt_reltoken(&tty_token);
682 * Adjust pgrp jobc counters when specified process changes process group.
683 * We count the number of processes in each process group that "qualify"
684 * the group for terminal job control (those with a parent in a different
685 * process group of the same session). If that count reaches zero, the
686 * process group becomes orphaned. Check both the specified process'
687 * process group and that of its children.
688 * entering == 0 => p is leaving specified group.
689 * entering == 1 => p is entering specified group.
694 fixjobc(struct proc *p, struct pgrp *pgrp, int entering)
696 struct pgrp *hispgrp;
697 struct session *mysession;
701 * Check p's parent to see whether p qualifies its own process
702 * group; if so, adjust count for p's process group.
704 lwkt_gettoken(&p->p_token); /* p_children scan */
705 lwkt_gettoken(&pgrp->pg_token);
707 mysession = pgrp->pg_session;
708 if ((hispgrp = p->p_pptr->p_pgrp) != pgrp &&
709 hispgrp->pg_session == mysession) {
712 else if (--pgrp->pg_jobc == 0)
717 * Check this process' children to see whether they qualify
718 * their process groups; if so, adjust counts for children's
721 LIST_FOREACH(np, &p->p_children, p_sibling) {
723 lwkt_gettoken(&np->p_token);
724 if ((hispgrp = np->p_pgrp) != pgrp &&
725 hispgrp->pg_session == mysession &&
726 np->p_stat != SZOMB) {
728 lwkt_gettoken(&hispgrp->pg_token);
731 else if (--hispgrp->pg_jobc == 0)
733 lwkt_reltoken(&hispgrp->pg_token);
736 lwkt_reltoken(&np->p_token);
739 KKASSERT(pgrp->pg_refs > 0);
740 lwkt_reltoken(&pgrp->pg_token);
741 lwkt_reltoken(&p->p_token);
745 * A process group has become orphaned;
746 * if there are any stopped processes in the group,
747 * hang-up all process in that group.
749 * The caller must hold pg_token.
752 orphanpg(struct pgrp *pg)
756 LIST_FOREACH(p, &pg->pg_members, p_pglist) {
757 if (p->p_stat == SSTOP) {
758 LIST_FOREACH(p, &pg->pg_members, p_pglist) {
768 * Add a new process to the allproc list and the PID hash. This
769 * also assigns a pid to the new process.
774 proc_add_allproc(struct proc *p)
778 if ((random_offset = randompid) != 0) {
780 random_offset = karc4random() % random_offset;
784 lwkt_gettoken(&proc_token);
785 p->p_pid = proc_getnewpid_locked(random_offset);
786 LIST_INSERT_HEAD(&allproc, p, p_list);
787 LIST_INSERT_HEAD(PIDHASH(p->p_pid), p, p_hash);
788 lwkt_reltoken(&proc_token);
792 * Calculate a new process pid. This function is integrated into
793 * proc_add_allproc() to guarentee that the new pid is not reused before
794 * the new process can be added to the allproc list.
796 * The caller must hold proc_token.
800 proc_getnewpid_locked(int random_offset)
802 static pid_t nextpid;
803 static pid_t pidchecked;
807 * Find an unused process ID. We remember a range of unused IDs
808 * ready to use (from nextpid+1 through pidchecked-1).
810 nextpid = nextpid + 1 + random_offset;
813 * If the process ID prototype has wrapped around,
814 * restart somewhat above 0, as the low-numbered procs
815 * tend to include daemons that don't exit.
817 if (nextpid >= PID_MAX) {
818 nextpid = nextpid % PID_MAX;
823 if (nextpid >= pidchecked) {
826 pidchecked = PID_MAX;
829 * Scan the active and zombie procs to check whether this pid
830 * is in use. Remember the lowest pid that's greater
831 * than nextpid, so we can avoid checking for a while.
833 * NOTE: Processes in the midst of being forked may not
834 * yet have p_pgrp and p_pgrp->pg_session set up
835 * yet, so we have to check for NULL.
837 * Processes being torn down should be interlocked
838 * with proc_token prior to the clearing of their
841 p = LIST_FIRST(&allproc);
843 for (; p != NULL; p = LIST_NEXT(p, p_list)) {
844 while (p->p_pid == nextpid ||
845 (p->p_pgrp && p->p_pgrp->pg_id == nextpid) ||
846 (p->p_pgrp && p->p_session &&
847 p->p_session->s_sid == nextpid)) {
849 if (nextpid >= pidchecked)
852 if (p->p_pid > nextpid && pidchecked > p->p_pid)
853 pidchecked = p->p_pid;
855 p->p_pgrp->pg_id > nextpid &&
856 pidchecked > p->p_pgrp->pg_id) {
857 pidchecked = p->p_pgrp->pg_id;
859 if (p->p_pgrp && p->p_session &&
860 p->p_session->s_sid > nextpid &&
861 pidchecked > p->p_session->s_sid) {
862 pidchecked = p->p_session->s_sid;
867 p = LIST_FIRST(&zombproc);
875 * Called from exit1 to remove a process from the allproc
876 * list and move it to the zombie list.
878 * Caller must hold p->p_token. We are required to wait until p_lock
879 * becomes zero before we can manipulate the list, allowing allproc
880 * scans to guarantee consistency during a list scan.
883 proc_move_allproc_zombie(struct proc *p)
885 lwkt_gettoken(&proc_token);
886 PSTALL(p, "reap1", 0);
887 LIST_REMOVE(p, p_list);
888 LIST_INSERT_HEAD(&zombproc, p, p_list);
889 LIST_REMOVE(p, p_hash);
891 lwkt_reltoken(&proc_token);
896 * This routine is called from kern_wait() and will remove the process
897 * from the zombie list and the sibling list. This routine will block
898 * if someone has a lock on the proces (p_lock).
900 * Caller must hold p->p_token. We are required to wait until p_lock
901 * becomes zero before we can manipulate the list, allowing allproc
902 * scans to guarantee consistency during a list scan.
905 proc_remove_zombie(struct proc *p)
907 lwkt_gettoken(&proc_token);
908 PSTALL(p, "reap2", 0);
909 LIST_REMOVE(p, p_list); /* off zombproc */
910 LIST_REMOVE(p, p_sibling);
912 lwkt_reltoken(&proc_token);
916 * Handle various requirements prior to returning to usermode. Called from
917 * platform trap and system call code.
920 lwpuserret(struct lwp *lp)
922 struct proc *p = lp->lwp_proc;
924 if (lp->lwp_mpflags & LWP_MP_VNLRU) {
925 atomic_clear_int(&lp->lwp_mpflags, LWP_MP_VNLRU);
928 if (lp->lwp_mpflags & LWP_MP_WEXIT) {
929 lwkt_gettoken(&p->p_token);
931 lwkt_reltoken(&p->p_token); /* NOT REACHED */
936 * Kernel threads run from user processes can also accumulate deferred
937 * actions which need to be acted upon. Callers include:
939 * nfsd - Can allocate lots of vnodes
942 lwpkthreaddeferred(void)
944 struct lwp *lp = curthread->td_lwp;
947 if (lp->lwp_mpflags & LWP_MP_VNLRU) {
948 atomic_clear_int(&lp->lwp_mpflags, LWP_MP_VNLRU);
955 * Scan all processes on the allproc list. The process is automatically
956 * held for the callback. A return value of -1 terminates the loop.
958 * The callback is made with the process held and proc_token held.
960 * We limit the scan to the number of processes as-of the start of
961 * the scan so as not to get caught up in an endless loop if new processes
962 * are created more quickly than we can scan the old ones. Add a little
963 * slop to try to catch edge cases since nprocs can race.
968 allproc_scan(int (*callback)(struct proc *, void *), void *data)
972 int limit = nprocs + ncpus;
975 * proc_token protects the allproc list and PHOLD() prevents the
976 * process from being removed from the allproc list or the zombproc
979 lwkt_gettoken(&proc_token);
980 LIST_FOREACH(p, &allproc, p_list) {
982 r = callback(p, data);
989 lwkt_reltoken(&proc_token);
993 * Scan all lwps of processes on the allproc list. The lwp is automatically
994 * held for the callback. A return value of -1 terminates the loop.
996 * The callback is made with the proces and lwp both held, and proc_token held.
1001 alllwp_scan(int (*callback)(struct lwp *, void *), void *data)
1008 * proc_token protects the allproc list and PHOLD() prevents the
1009 * process from being removed from the allproc list or the zombproc
1012 lwkt_gettoken(&proc_token);
1013 LIST_FOREACH(p, &allproc, p_list) {
1015 FOREACH_LWP_IN_PROC(lp, p) {
1017 r = callback(lp, data);
1024 lwkt_reltoken(&proc_token);
1028 * Scan all processes on the zombproc list. The process is automatically
1029 * held for the callback. A return value of -1 terminates the loop.
1032 * The callback is made with the proces held and proc_token held.
1035 zombproc_scan(int (*callback)(struct proc *, void *), void *data)
1040 lwkt_gettoken(&proc_token);
1041 LIST_FOREACH(p, &zombproc, p_list) {
1043 r = callback(p, data);
1048 lwkt_reltoken(&proc_token);
1051 #include "opt_ddb.h"
1053 #include <ddb/ddb.h>
1058 DB_SHOW_COMMAND(pgrpdump, pgrpdump)
1064 for (i = 0; i <= pgrphash; i++) {
1065 if (!LIST_EMPTY(&pgrphashtbl[i])) {
1066 kprintf("\tindx %d\n", i);
1067 LIST_FOREACH(pgrp, &pgrphashtbl[i], pg_hash) {
1069 "\tpgrp %p, pgid %ld, sess %p, sesscnt %d, mem %p\n",
1070 (void *)pgrp, (long)pgrp->pg_id,
1071 (void *)pgrp->pg_session,
1072 pgrp->pg_session->s_count,
1073 (void *)LIST_FIRST(&pgrp->pg_members));
1074 LIST_FOREACH(p, &pgrp->pg_members, p_pglist) {
1075 kprintf("\t\tpid %ld addr %p pgrp %p\n",
1076 (long)p->p_pid, (void *)p,
1086 * Locate a process on the zombie list. Return a process or NULL.
1087 * The returned process will be referenced and the caller must release
1090 * No other requirements.
1097 lwkt_gettoken(&proc_token);
1098 LIST_FOREACH(p, &zombproc, p_list) {
1099 if (p->p_pid == pid) {
1101 lwkt_reltoken(&proc_token);
1105 lwkt_reltoken(&proc_token);
1110 * The caller must hold proc_token.
1113 sysctl_out_proc(struct proc *p, struct sysctl_req *req, int flags)
1115 struct kinfo_proc ki;
1117 int skp = 0, had_output = 0;
1120 bzero(&ki, sizeof(ki));
1121 lwkt_gettoken(&p->p_token);
1122 fill_kinfo_proc(p, &ki);
1123 if ((flags & KERN_PROC_FLAG_LWP) == 0)
1126 FOREACH_LWP_IN_PROC(lp, p) {
1128 fill_kinfo_lwp(lp, &ki.kp_lwp);
1130 error = SYSCTL_OUT(req, &ki, sizeof(ki));
1137 lwkt_reltoken(&p->p_token);
1138 /* We need to output at least the proc, even if there is no lwp. */
1139 if (had_output == 0) {
1140 error = SYSCTL_OUT(req, &ki, sizeof(ki));
1146 * The caller must hold proc_token.
1149 sysctl_out_proc_kthread(struct thread *td, struct sysctl_req *req, int flags)
1151 struct kinfo_proc ki;
1154 fill_kinfo_proc_kthread(td, &ki);
1155 error = SYSCTL_OUT(req, &ki, sizeof(ki));
1165 sysctl_kern_proc(SYSCTL_HANDLER_ARGS)
1167 int *name = (int*) arg1;
1168 int oid = oidp->oid_number;
1169 u_int namelen = arg2;
1171 struct proclist *plist;
1173 struct thread *marker;
1174 int doingzomb, flags = 0;
1178 struct ucred *cr1 = curproc->p_ucred;
1180 flags = oid & KERN_PROC_FLAGMASK;
1181 oid &= ~KERN_PROC_FLAGMASK;
1183 if ((oid == KERN_PROC_ALL && namelen != 0) ||
1184 (oid != KERN_PROC_ALL && namelen != 1)) {
1189 * proc_token protects the allproc list and PHOLD() prevents the
1190 * process from being removed from the allproc list or the zombproc
1193 lwkt_gettoken(&proc_token);
1194 if (oid == KERN_PROC_PID) {
1195 p = pfindn((pid_t)name[0]);
1198 if (!PRISON_CHECK(cr1, p->p_ucred))
1201 error = sysctl_out_proc(p, req, flags);
1207 /* overestimate by 5 procs */
1208 error = SYSCTL_OUT(req, 0, sizeof (struct kinfo_proc) * 5);
1212 for (doingzomb = 0; doingzomb <= 1; doingzomb++) {
1217 LIST_FOREACH(p, plist, p_list) {
1219 * Show a user only their processes.
1221 if ((!ps_showallprocs) && p_trespass(cr1, p->p_ucred))
1224 * Skip embryonic processes.
1226 if (p->p_stat == SIDL)
1229 * TODO - make more efficient (see notes below).
1233 case KERN_PROC_PGRP:
1234 /* could do this by traversing pgrp */
1235 if (p->p_pgrp == NULL ||
1236 p->p_pgrp->pg_id != (pid_t)name[0])
1241 if ((p->p_flags & P_CONTROLT) == 0 ||
1242 p->p_session == NULL ||
1243 p->p_session->s_ttyp == NULL ||
1244 dev2udev(p->p_session->s_ttyp->t_dev) !=
1250 if (p->p_ucred == NULL ||
1251 p->p_ucred->cr_uid != (uid_t)name[0])
1255 case KERN_PROC_RUID:
1256 if (p->p_ucred == NULL ||
1257 p->p_ucred->cr_ruid != (uid_t)name[0])
1262 if (!PRISON_CHECK(cr1, p->p_ucred))
1265 error = sysctl_out_proc(p, req, flags);
1273 * Iterate over all active cpus and scan their thread list. Start
1274 * with the next logical cpu and end with our original cpu. We
1275 * migrate our own thread to each target cpu in order to safely scan
1276 * its thread list. In the last loop we migrate back to our original
1279 origcpu = mycpu->gd_cpuid;
1280 if (!ps_showallthreads || jailed(cr1))
1283 marker = kmalloc(sizeof(struct thread), M_TEMP, M_WAITOK|M_ZERO);
1284 marker->td_flags = TDF_MARKER;
1287 for (n = 1; n <= ncpus; ++n) {
1291 nid = (origcpu + n) % ncpus;
1292 if ((smp_active_mask & CPUMASK(nid)) == 0)
1294 rgd = globaldata_find(nid);
1295 lwkt_setcpu_self(rgd);
1298 TAILQ_INSERT_TAIL(&rgd->gd_tdallq, marker, td_allq);
1300 while ((td = TAILQ_PREV(marker, lwkt_queue, td_allq)) != NULL) {
1301 TAILQ_REMOVE(&rgd->gd_tdallq, marker, td_allq);
1302 TAILQ_INSERT_BEFORE(td, marker, td_allq);
1303 if (td->td_flags & TDF_MARKER)
1312 case KERN_PROC_PGRP:
1315 case KERN_PROC_RUID:
1318 error = sysctl_out_proc_kthread(td, req,
1327 TAILQ_REMOVE(&rgd->gd_tdallq, marker, td_allq);
1333 kfree(marker, M_TEMP);
1336 lwkt_reltoken(&proc_token);
1341 * This sysctl allows a process to retrieve the argument list or process
1342 * title for another process without groping around in the address space
1343 * of the other process. It also allow a process to set its own "process
1344 * title to a string of its own choice.
1349 sysctl_kern_proc_args(SYSCTL_HANDLER_ARGS)
1351 int *name = (int*) arg1;
1352 u_int namelen = arg2;
1357 struct ucred *cr1 = curproc->p_ucred;
1362 p = pfind((pid_t)name[0]);
1365 lwkt_gettoken(&p->p_token);
1367 if ((!ps_argsopen) && p_trespass(cr1, p->p_ucred))
1370 if (req->newptr && curproc != p) {
1374 if (req->oldptr && (pa = p->p_args) != NULL) {
1375 refcount_acquire(&pa->ar_ref);
1376 error = SYSCTL_OUT(req, pa->ar_args, pa->ar_length);
1377 if (refcount_release(&pa->ar_ref))
1380 if (req->newptr == NULL)
1383 if (req->newlen + sizeof(struct pargs) > ps_arg_cache_limit) {
1387 pa = kmalloc(sizeof(struct pargs) + req->newlen, M_PARGS, M_WAITOK);
1388 refcount_init(&pa->ar_ref, 1);
1389 pa->ar_length = req->newlen;
1390 error = SYSCTL_IN(req, pa->ar_args, req->newlen);
1398 * Replace p_args with the new pa. p_args may have previously
1405 KKASSERT(opa->ar_ref > 0);
1406 if (refcount_release(&opa->ar_ref)) {
1407 kfree(opa, M_PARGS);
1413 lwkt_reltoken(&p->p_token);
1420 sysctl_kern_proc_cwd(SYSCTL_HANDLER_ARGS)
1422 int *name = (int*) arg1;
1423 u_int namelen = arg2;
1426 char *fullpath, *freepath;
1427 struct ucred *cr1 = curproc->p_ucred;
1432 p = pfind((pid_t)name[0]);
1435 lwkt_gettoken(&p->p_token);
1438 * If we are not allowed to see other args, we certainly shouldn't
1439 * get the cwd either. Also check the usual trespassing.
1441 if ((!ps_argsopen) && p_trespass(cr1, p->p_ucred))
1444 if (req->oldptr && p->p_fd != NULL && p->p_fd->fd_ncdir.ncp) {
1445 struct nchandle nch;
1447 cache_copy(&p->p_fd->fd_ncdir, &nch);
1448 error = cache_fullpath(p, &nch, NULL,
1449 &fullpath, &freepath, 0);
1453 error = SYSCTL_OUT(req, fullpath, strlen(fullpath) + 1);
1454 kfree(freepath, M_TEMP);
1459 lwkt_reltoken(&p->p_token);
1465 SYSCTL_NODE(_kern, KERN_PROC, proc, CTLFLAG_RD, 0, "Process table");
1467 SYSCTL_PROC(_kern_proc, KERN_PROC_ALL, all, CTLFLAG_RD|CTLTYPE_STRUCT,
1468 0, 0, sysctl_kern_proc, "S,proc", "Return entire process table");
1470 SYSCTL_NODE(_kern_proc, KERN_PROC_PGRP, pgrp, CTLFLAG_RD,
1471 sysctl_kern_proc, "Process table");
1473 SYSCTL_NODE(_kern_proc, KERN_PROC_TTY, tty, CTLFLAG_RD,
1474 sysctl_kern_proc, "Process table");
1476 SYSCTL_NODE(_kern_proc, KERN_PROC_UID, uid, CTLFLAG_RD,
1477 sysctl_kern_proc, "Process table");
1479 SYSCTL_NODE(_kern_proc, KERN_PROC_RUID, ruid, CTLFLAG_RD,
1480 sysctl_kern_proc, "Process table");
1482 SYSCTL_NODE(_kern_proc, KERN_PROC_PID, pid, CTLFLAG_RD,
1483 sysctl_kern_proc, "Process table");
1485 SYSCTL_NODE(_kern_proc, (KERN_PROC_ALL | KERN_PROC_FLAG_LWP), all_lwp, CTLFLAG_RD,
1486 sysctl_kern_proc, "Process table");
1488 SYSCTL_NODE(_kern_proc, (KERN_PROC_PGRP | KERN_PROC_FLAG_LWP), pgrp_lwp, CTLFLAG_RD,
1489 sysctl_kern_proc, "Process table");
1491 SYSCTL_NODE(_kern_proc, (KERN_PROC_TTY | KERN_PROC_FLAG_LWP), tty_lwp, CTLFLAG_RD,
1492 sysctl_kern_proc, "Process table");
1494 SYSCTL_NODE(_kern_proc, (KERN_PROC_UID | KERN_PROC_FLAG_LWP), uid_lwp, CTLFLAG_RD,
1495 sysctl_kern_proc, "Process table");
1497 SYSCTL_NODE(_kern_proc, (KERN_PROC_RUID | KERN_PROC_FLAG_LWP), ruid_lwp, CTLFLAG_RD,
1498 sysctl_kern_proc, "Process table");
1500 SYSCTL_NODE(_kern_proc, (KERN_PROC_PID | KERN_PROC_FLAG_LWP), pid_lwp, CTLFLAG_RD,
1501 sysctl_kern_proc, "Process table");
1503 SYSCTL_NODE(_kern_proc, KERN_PROC_ARGS, args, CTLFLAG_RW | CTLFLAG_ANYBODY,
1504 sysctl_kern_proc_args, "Process argument list");
1506 SYSCTL_NODE(_kern_proc, KERN_PROC_CWD, cwd, CTLFLAG_RD | CTLFLAG_ANYBODY,
1507 sysctl_kern_proc_cwd, "Process argument list");