Split PID from TID, giving processes a PID unrelated to the TID of their

initial thread

ok jsing@ kettenis@

25 files changed, 150 insertions, 113 deletions

diff --git a/sys/arch/sparc64/sparc64/db_interface.c b/sys/arch/sparc64/sparc64/db_interface.c
index 039da18b58e..eb84bb99838 100644
--- a/sys/arch/sparc64/sparc64/db_interface.c
+++ b/sys/arch/sparc64/sparc64/db_interface.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: db_interface.c,v 1.46 2016/10/18 00:43:57 guenther Exp $	*/
+/*	$OpenBSD: db_interface.c,v 1.47 2016/11/07 00:26:33 guenther Exp $	*/
 /*	$NetBSD: db_interface.c,v 1.61 2001/07/31 06:55:47 eeh Exp $ */
 
 /*
@@ -1062,23 +1062,23 @@ db_setpcb(addr, have_addr, count, modif)
 	struct proc *p;
 
 	if (!have_addr) {
-		db_printf("What PID do you want to map in?\n");
+		db_printf("What TID do you want to map in?\n");
 		return;
 	}
 
 	LIST_FOREACH(p, &allproc, p_list) {
-		if (p->p_stat && p->p_pid == addr) {
+		if (p->p_stat && p->p_tid == addr) {
 			curproc = p;
 			curpcb = (struct pcb*)p->p_addr;
 			if (p->p_vmspace->vm_map.pmap->pm_ctx) {
 				switchtoctx(p->p_vmspace->vm_map.pmap->pm_ctx);
 				return;
 			}
-			db_printf("PID %ld has a null context.\n", addr);
+			db_printf("TID %ld has a null context.\n", addr);
 			return;
 		}
 	}
-	db_printf("PID %ld not found.\n", addr);
+	db_printf("TID %ld not found.\n", addr);
 }
 
 
diff --git a/sys/dev/pci/drm/drm_irq.c b/sys/dev/pci/drm/drm_irq.c
index e8b4fbcc025..1f15e48cdeb 100644
--- a/sys/dev/pci/drm/drm_irq.c
+++ b/sys/dev/pci/drm/drm_irq.c
@@ -1111,7 +1111,7 @@ static int drm_queue_vblank_event(struct drm_device *dev, int pipe,
 	}
 
 	e->pipe = pipe;
-	e->base.pid = curproc->p_pid;
+	e->base.pid = curproc->p_tid;	/* XXX */
 	e->event.base.type = DRM_EVENT_VBLANK;
 	e->event.base.length = sizeof e->event;
 	e->event.user_data = vblwait->request.signal;
@@ -1138,7 +1138,7 @@ static int drm_queue_vblank_event(struct drm_device *dev, int pipe,
 	DRM_DEBUG("event on vblank count %d, current %d, crtc %d\n",
 		  vblwait->request.sequence, seq, pipe);
 
-	trace_drm_vblank_event_queued(curproc->p_pid, pipe,
+	trace_drm_vblank_event_queued(curproc->p_tid, pipe,
 				      vblwait->request.sequence);
 
 	e->event.sequence = vblwait->request.sequence;
diff --git a/sys/dev/wscons/wsdisplay.c b/sys/dev/wscons/wsdisplay.c
index 3169c0aacfd..131c511fc79 100644
--- a/sys/dev/wscons/wsdisplay.c
+++ b/sys/dev/wscons/wsdisplay.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: wsdisplay.c,v 1.124 2015/09/08 11:13:20 deraadt Exp $ */
+/* $OpenBSD: wsdisplay.c,v 1.125 2016/11/07 00:26:33 guenther Exp $ */
 /* $NetBSD: wsdisplay.c,v 1.82 2005/02/27 00:27:52 perry Exp $ */
 
 /*
@@ -1426,7 +1426,7 @@ wsdisplaystart(struct tty *tp)
 		splx(s);
 		return;
 	}
-	if (tp->t_outq.c_cc == 0 && tp->t_wsel.si_selpid == 0)
+	if (tp->t_outq.c_cc == 0 && tp->t_wsel.si_seltid == 0)
 		goto low;
 
 	if ((scr = sc->sc_scr[WSDISPLAYSCREEN(tp->t_dev)]) == NULL) {
diff --git a/sys/kern/exec_elf.c b/sys/kern/exec_elf.c
index 87c850ffeef..d51aecd0669 100644
--- a/sys/kern/exec_elf.c
+++ b/sys/kern/exec_elf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: exec_elf.c,v 1.128 2016/10/05 02:31:52 guenther Exp $	*/
+/*	$OpenBSD: exec_elf.c,v 1.129 2016/11/07 00:26:32 guenther Exp $	*/
 
 /*
  * Copyright (c) 1996 Per Fogelstrom
@@ -1335,7 +1335,7 @@ ELFNAMEEND(coredump_note)(struct proc *p, void *iocookie, size_t *sizep)
 	size = 0;
 
 	snprintf(name, sizeof(name)-ELFROUNDSIZE, "%s@%d",
-	    "OpenBSD", p->p_pid);
+	    "OpenBSD", p->p_tid + THREAD_PID_OFFSET);
 	namesize = strlen(name) + 1;
 	memset(name + namesize, 0, elfround(namesize) - namesize);
 
diff --git a/sys/kern/init_main.c b/sys/kern/init_main.c
index 90cdd985516..47408b45081 100644
--- a/sys/kern/init_main.c
+++ b/sys/kern/init_main.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: init_main.c,v 1.261 2016/10/24 04:38:44 dlg Exp $	*/
+/*	$OpenBSD: init_main.c,v 1.262 2016/11/07 00:26:32 guenther Exp $	*/
 /*	$NetBSD: init_main.c,v 1.84.4.1 1996/06/02 09:08:06 mrg Exp $	*/
 
 /*
@@ -272,6 +272,7 @@ main(void *framep)
 	process_initialize(pr, p);
 
 	LIST_INSERT_HEAD(&allprocess, pr, ps_list);
+	LIST_INSERT_HEAD(PIDHASH(0), pr, ps_hash);
 	atomic_setbits_int(&pr->ps_flags, PS_SYSTEM);
 
 	/* Set the default routing table/domain. */
@@ -279,7 +280,7 @@ main(void *framep)
 
 	LIST_INSERT_HEAD(&allproc, p, p_list);
 	pr->ps_pgrp = &pgrp0;
-	LIST_INSERT_HEAD(PIDHASH(0), p, p_hash);
+	LIST_INSERT_HEAD(TIDHASH(0), p, p_hash);
 	LIST_INSERT_HEAD(PGRPHASH(0), &pgrp0, pg_hash);
 	LIST_INIT(&pgrp0.pg_members);
 	LIST_INSERT_HEAD(&pgrp0.pg_members, pr, ps_pglist);
diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c
index 54eba67f026..5d0f0915fad 100644
--- a/sys/kern/kern_exit.c
+++ b/sys/kern/kern_exit.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_exit.c,v 1.157 2016/04/25 20:00:33 tedu Exp $	*/
+/*	$OpenBSD: kern_exit.c,v 1.158 2016/11/07 00:26:32 guenther Exp $	*/
 /*	$NetBSD: kern_exit.c,v 1.39 1996/04/22 01:38:25 christos Exp $	*/
 
 /*
@@ -265,6 +265,7 @@ exit1(struct proc *p, int rv, int flags)
 	LIST_REMOVE(p, p_list);
 
 	if ((p->p_flag & P_THREAD) == 0) {
+		LIST_REMOVE(pr, ps_hash);
 		LIST_REMOVE(pr, ps_list);
 
 		if ((pr->ps_flags & PS_NOZOMBIE) == 0)
@@ -275,7 +276,7 @@ exit1(struct proc *p, int rv, int flags)
 			 * the lists scanned by ispidtaken(), so block
 			 * fast reuse of the pid now.
 			 */
-			freepid(p->p_pid);
+			freepid(pr->ps_pid);
 		}
 
 		/*
@@ -515,16 +516,17 @@ dowait4(struct proc *q, pid_t pid, int *statusp, int options,
 loop:
 	nfound = 0;
 	LIST_FOREACH(pr, &q->p_p->ps_children, ps_sibling) {
-		p = pr->ps_mainproc;
 		if ((pr->ps_flags & PS_NOZOMBIE) ||
 		    (pid != WAIT_ANY &&
-		    p->p_pid != pid &&
+		    pr->ps_pid != pid &&
 		    pr->ps_pgid != -pid))
 			continue;
 
+		p = pr->ps_mainproc;
+
 		nfound++;
 		if (pr->ps_flags & PS_ZOMBIE) {
-			retval[0] = p->p_pid;
+			retval[0] = pr->ps_pid;
 
 			if (statusp != NULL)
 				*statusp = p->p_xstat;	/* convert to int */
@@ -540,7 +542,7 @@ loop:
 			single_thread_wait(pr);
 
 			atomic_setbits_int(&pr->ps_flags, PS_WAITED);
-			retval[0] = p->p_pid;
+			retval[0] = pr->ps_pid;
 
 			if (statusp != NULL)
 				*statusp = W_STOPCODE(pr->ps_single->p_xstat);
@@ -554,7 +556,7 @@ loop:
 		    (pr->ps_flags & PS_TRACED ||
 		    options & WUNTRACED)) {
 			atomic_setbits_int(&pr->ps_flags, PS_WAITED);
-			retval[0] = p->p_pid;
+			retval[0] = pr->ps_pid;
 
 			if (statusp != NULL)
 				*statusp = W_STOPCODE(p->p_xstat);
@@ -564,7 +566,7 @@ loop:
 		}
 		if ((options & WCONTINUED) && (p->p_flag & P_CONTINUED)) {
 			atomic_clearbits_int(&p->p_flag, P_CONTINUED);
-			retval[0] = p->p_pid;
+			retval[0] = pr->ps_pid;
 
 			if (statusp != NULL)
 				*statusp = _WCONTINUED;
@@ -607,7 +609,7 @@ proc_finish_wait(struct proc *waiter, struct proc *p)
 		rup = &waiter->p_p->ps_cru;
 		ruadd(rup, pr->ps_ru);
 		LIST_REMOVE(pr, ps_list);	/* off zombprocess */
-		freepid(p->p_pid);
+		freepid(pr->ps_pid);
 		process_zap(pr);
 	}
 }
diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index 5e8fde114b4..9a82d5bbe56 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_fork.c,v 1.191 2016/10/22 02:55:36 guenther Exp $	*/
+/*	$OpenBSD: kern_fork.c,v 1.192 2016/11/07 00:26:32 guenther Exp $	*/
 /*	$NetBSD: kern_fork.c,v 1.29 1996/02/09 18:59:34 christos Exp $	*/
 
 /*
@@ -76,7 +76,9 @@ struct	forkstat forkstat;
 
 void fork_return(void *);
 void tfork_child_return(void *);
-int pidtaken(pid_t);
+pid_t alloctid(void);
+pid_t allocpid(void);
+int ispidtaken(pid_t);
 
 void process_new(struct proc *, struct process *, int);
 
@@ -191,6 +193,7 @@ process_new(struct proc *p, struct process *parent, int flags)
 	    (caddr_t)&pr->ps_endcopy - (caddr_t)&pr->ps_startcopy);
 
 	process_initialize(pr, p);
+	pr->ps_pid = allocpid();
 
 	/* post-copy fixups */
 	pr->ps_pptr = parent;
@@ -428,11 +431,12 @@ fork1(struct proc *curp, int flags, void *stack, pid_t *tidptr,
 	if (pr->ps_flags & PS_TRACED && flags & FORK_FORK)
 		newptstat = malloc(sizeof(*newptstat), M_SUBPROC, M_WAITOK);
 
-	p->p_pid = allocpid();
+	p->p_tid = alloctid();
 
 	LIST_INSERT_HEAD(&allproc, p, p_list);
-	LIST_INSERT_HEAD(PIDHASH(p->p_pid), p, p_hash);
+	LIST_INSERT_HEAD(TIDHASH(p->p_tid), p, p_hash);
 	if ((flags & FORK_THREAD) == 0) {
+		LIST_INSERT_HEAD(PIDHASH(pr->ps_pid), pr, ps_hash);
 		LIST_INSERT_AFTER(curpr, pr, ps_pglist);
 		LIST_INSERT_HEAD(&curpr->ps_children, pr, ps_sibling);
 
@@ -466,9 +470,9 @@ fork1(struct proc *curp, int flags, void *stack, pid_t *tidptr,
 	}
 
 	if (tidptr != NULL) {
-		pid_t	pid = p->p_pid + THREAD_PID_OFFSET;
+		pid_t	tid = p->p_tid + THREAD_PID_OFFSET;
 
-		if (copyout(&pid, tidptr, sizeof(pid)))
+		if (copyout(&tid, tidptr, sizeof(tid)))
 			psignal(curp, SIGSEGV);
 	}
 
@@ -500,7 +504,7 @@ fork1(struct proc *curp, int flags, void *stack, pid_t *tidptr,
 	 * Notify any interested parties about the new process.
 	 */
 	if ((flags & FORK_THREAD) == 0)
-		KNOTE(&curpr->ps_klist, NOTE_FORK | p->p_pid);
+		KNOTE(&curpr->ps_klist, NOTE_FORK | pr->ps_pid);
 
 	/*
 	 * Update stats now that we know the fork was successful.
@@ -539,13 +543,27 @@ fork1(struct proc *curp, int flags, void *stack, pid_t *tidptr,
 	 * marking us as parent via retval[1].
 	 */
 	if (retval != NULL) {
-		retval[0] = p->p_pid +
-		    (flags & FORK_THREAD ? THREAD_PID_OFFSET : 0);
+		retval[0] = (flags & FORK_THREAD) == 0 ? pr->ps_pid :
+		    (p->p_tid + THREAD_PID_OFFSET);
 		retval[1] = 0;
 	}
 	return (0);
 }
 
+/* Find an unused tid */
+pid_t
+alloctid(void)
+{
+	pid_t tid;
+
+	do {
+		/* (0 .. TID_MASK+1] */
+		tid = 1 + (arc4random() & TID_MASK);
+	} while (pfind(tid) != NULL);
+
+	return (tid);
+}
+
 /*
  * Checks for current use of a pid, either as a pid or pgid.
  */
@@ -559,7 +577,7 @@ ispidtaken(pid_t pid)
 		if (pid == oldpids[i])
 			return (1);
 
-	if (pfind(pid) != NULL)
+	if (prfind(pid) != NULL)
 		return (1);
 	if (pgfind(pid) != NULL)
 		return (1);
diff --git a/sys/kern/kern_kthread.c b/sys/kern/kern_kthread.c
index 7b8ea85bbba..7b25abb16b7 100644
--- a/sys/kern/kern_kthread.c
+++ b/sys/kern/kern_kthread.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_kthread.c,v 1.38 2015/03/14 03:38:50 jsg Exp $	*/
+/*	$OpenBSD: kern_kthread.c,v 1.39 2016/11/07 00:26:32 guenther Exp $	*/
 /*	$NetBSD: kern_kthread.c,v 1.3 1998/12/22 21:21:36 kleink Exp $	*/
 
 /*-
@@ -94,7 +94,7 @@ kthread_exit(int ecode)
 	 */
 	if (ecode != 0)
 		printf("WARNING: thread `%s' (%d) exits with status %d\n",
-		    curproc->p_comm, curproc->p_pid, ecode);
+		    curproc->p_comm, curproc->p_tid, ecode);
 
 	exit1(curproc, W_EXITCODE(ecode, 0), EXIT_NORMAL);
 
diff --git a/sys/kern/kern_ktrace.c b/sys/kern/kern_ktrace.c
index 97c1074334a..2ba5dc967db 100644
--- a/sys/kern/kern_ktrace.c
+++ b/sys/kern/kern_ktrace.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_ktrace.c,v 1.88 2016/03/19 12:04:15 natano Exp $	*/
+/*	$OpenBSD: kern_ktrace.c,v 1.89 2016/11/07 00:26:32 guenther Exp $	*/
 /*	$NetBSD: kern_ktrace.c,v 1.23 1996/02/09 18:59:36 christos Exp $	*/
 
 /*
@@ -136,7 +136,7 @@ void
 ktrinitheader(struct ktr_header *kth, struct proc *p, int type)
 {
 	ktrinitheaderraw(kth, type, p->p_p->ps_pid,
-	    p->p_pid + THREAD_PID_OFFSET);
+	    p->p_tid + THREAD_PID_OFFSET);
 	memcpy(kth->ktr_comm, p->p_comm, MAXCOMLEN);
 }
 
diff --git a/sys/kern/kern_proc.c b/sys/kern/kern_proc.c
index 51a428d2af8..c84276b4e1c 100644
--- a/sys/kern/kern_proc.c
+++ b/sys/kern/kern_proc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_proc.c,v 1.70 2016/09/15 02:00:16 dlg Exp $	*/
+/*	$OpenBSD: kern_proc.c,v 1.71 2016/11/07 00:26:32 guenther Exp $	*/
 /*	$NetBSD: kern_proc.c,v 1.14 1996/02/09 18:59:41 christos Exp $	*/
 
 /*
@@ -56,6 +56,8 @@ u_long uihash;		/* size of hash table - 1 */
 /*
  * Other process lists
  */
+struct tidhashhead *tidhashtbl;
+u_long tidhash;
 struct pidhashhead *pidhashtbl;
 u_long pidhash;
 struct pgrphashhead *pgrphashtbl;
@@ -87,10 +89,11 @@ procinit(void)
 	LIST_INIT(&allproc);
 
 
-	pidhashtbl = hashinit(maxthread / 4, M_PROC, M_NOWAIT, &pidhash);
+	tidhashtbl = hashinit(maxthread / 4, M_PROC, M_NOWAIT, &tidhash);
+	pidhashtbl = hashinit(maxprocess / 4, M_PROC, M_NOWAIT, &pidhash);
 	pgrphashtbl = hashinit(maxprocess / 4, M_PROC, M_NOWAIT, &pgrphash);
 	uihashtbl = hashinit(maxprocess / 16, M_PROC, M_NOWAIT, &uihash);
-	if (!pidhashtbl || !pgrphashtbl || !uihashtbl)
+	if (!tidhashtbl || !pidhashtbl || !pgrphashtbl || !uihashtbl)
 		panic("procinit: malloc");
 
 	pool_init(&proc_pool, sizeof(struct proc), 0, IPL_NONE,
@@ -166,12 +169,12 @@ inferior(struct process *pr, struct process *parent)
  * Locate a proc (thread) by number
  */
 struct proc *
-pfind(pid_t pid)
+pfind(pid_t tid)
 {
 	struct proc *p;
 
-	LIST_FOREACH(p, PIDHASH(pid), p_hash)
-		if (p->p_pid == pid)
+	LIST_FOREACH(p, TIDHASH(tid), p_hash)
+		if (p->p_tid == tid)
 			return (p);
 	return (NULL);
 }
@@ -182,11 +185,11 @@ pfind(pid_t pid)
 struct process *
 prfind(pid_t pid)
 {
-	struct proc *p;
+	struct process *pr;
 
-	LIST_FOREACH(p, PIDHASH(pid), p_hash)
-		if (p->p_pid == pid)
-			return (p->p_flag & P_THREAD ? NULL : p->p_p);
+	LIST_FOREACH(pr, PIDHASH(pid), ps_hash)
+		if (pr->ps_pid == pid)
+			return (pr);
 	return (NULL);
 }
 
@@ -213,7 +216,7 @@ zombiefind(pid_t pid)
 	struct process *pr;
 
 	LIST_FOREACH(pr, &zombprocess, ps_list)
-		if (pr->ps_mainproc->p_pid == pid)
+		if (pr->ps_pid == pid)
 			return (pr);
 	return (NULL);
 }
@@ -418,7 +421,7 @@ proc_printit(struct proc *p, const char *modif,
 	else
 		pst = pstat[(int)p->p_stat - 1];
 
-	(*pr)("PROC (%s) pid=%d stat=%s\n", p->p_comm, p->p_pid, pst);
+	(*pr)("PROC (%s) tid=%d stat=%s\n", p->p_comm, p->p_tid, pst);
 	(*pr)("    flags process=%b proc=%b\n",
 	    p->p_p->ps_flags, PS_BITS, p->p_flag, P_BITS);
 	(*pr)("    pri=%u, usrpri=%u, nice=%d\n",
@@ -468,7 +471,7 @@ db_show_all_procs(db_expr_t addr, int haddr, db_expr_t count, char *modif)
 		    "COMMAND", "STRUCT PROC *", "UAREA *", "VMSPACE/VM_MAP");
 		break;
 	case 'n':
-		db_printf("   TID  %5s  %5s  %5s  S  %10s  %-12s  %-16s\n",
+		db_printf("   PID  %5s  %5s  %5s  S  %10s  %-12s  %-16s\n",
 		    "PPID", "PGRP", "UID", "FLAGS", "WAIT", "COMMAND");
 		break;
 	case 'w':
@@ -495,7 +498,7 @@ db_show_all_procs(db_expr_t addr, int haddr, db_expr_t count, char *modif)
 						continue;
 				}
 				db_printf("%c%5d  ", p == curproc ? '*' : ' ',
-					p->p_pid);
+				    *mode == 'n' ? pr->ps_pid : p->p_tid);
 
 				switch (*mode) {
 
diff --git a/sys/kern/kern_prot.c b/sys/kern/kern_prot.c
index ec9322bc426..9fae1d747c6 100644
--- a/sys/kern/kern_prot.c
+++ b/sys/kern/kern_prot.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_prot.c,v 1.66 2016/09/02 18:11:28 tedu Exp $	*/
+/*	$OpenBSD: kern_prot.c,v 1.67 2016/11/07 00:26:32 guenther Exp $	*/
 /*	$NetBSD: kern_prot.c,v 1.33 1996/02/09 18:59:42 christos Exp $	*/
 
 /*
@@ -78,7 +78,7 @@ int
 sys_getthrid(struct proc *p, void *v, register_t *retval)
 {
 
-	*retval = p->p_pid + THREAD_PID_OFFSET;
+	*retval = p->p_tid + THREAD_PID_OFFSET;
 	return (0);
 }
 
diff --git a/sys/kern/kern_sysctl.c b/sys/kern/kern_sysctl.c
index 294b28b095c..27b53c83382 100644
--- a/sys/kern/kern_sysctl.c
+++ b/sys/kern/kern_sysctl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_sysctl.c,v 1.318 2016/10/24 04:38:44 dlg Exp $	*/
+/*	$OpenBSD: kern_sysctl.c,v 1.319 2016/11/07 00:26:32 guenther Exp $	*/
 /*	$NetBSD: kern_sysctl.c,v 1.17 1996/05/20 17:49:05 mrg Exp $	*/
 
 /*-
@@ -1588,7 +1588,6 @@ fill_kproc(struct process *pr, struct kinfo_proc *ki, struct proc *p,
 	    show_pointers);
 
 	/* stuff that's too painful to generalize into the macros */
-	ki->p_pid = pr->ps_pid;
 	if (pr->ps_pptr)
 		ki->p_ppid = pr->ps_pptr->ps_pid;
 	if (s->s_leader)
@@ -1986,7 +1985,7 @@ sysctl_proc_vmmap(int *name, u_int namelen, void *oldp, size_t *oldlenp,
 	}
 
 	pid = name[0];
-	if (pid == cp->p_pid) {
+	if (pid == cp->p_p->ps_pid) {
 		/* Self process mapping. */
 		findpr = cp->p_p;
 	} else if (pid > 0) {
diff --git a/sys/kern/sys_generic.c b/sys/kern/sys_generic.c
index a2c2f3fb72f..cf08a3022be 100644
--- a/sys/kern/sys_generic.c
+++ b/sys/kern/sys_generic.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sys_generic.c,v 1.112 2016/07/05 00:35:09 tedu Exp $	*/
+/*	$OpenBSD: sys_generic.c,v 1.113 2016/11/07 00:26:33 guenther Exp $	*/
 /*	$NetBSD: sys_generic.c,v 1.24 1996/03/29 00:25:32 cgd Exp $	*/
 
 /*
@@ -778,16 +778,16 @@ void
 selrecord(struct proc *selector, struct selinfo *sip)
 {
 	struct proc *p;
-	pid_t mypid;
+	pid_t mytid;
 
-	mypid = selector->p_pid;
-	if (sip->si_selpid == mypid)
+	mytid = selector->p_tid;
+	if (sip->si_seltid == mytid)
 		return;
-	if (sip->si_selpid && (p = pfind(sip->si_selpid)) &&
+	if (sip->si_seltid && (p = pfind(sip->si_seltid)) &&
 	    p->p_wchan == (caddr_t)&selwait)
 		sip->si_flags |= SI_COLL;
 	else
-		sip->si_selpid = mypid;
+		sip->si_seltid = mytid;
 }
 
 /*
@@ -800,15 +800,15 @@ selwakeup(struct selinfo *sip)
 	int s;
 
 	KNOTE(&sip->si_note, 0);
-	if (sip->si_selpid == 0)
+	if (sip->si_seltid == 0)
 		return;
 	if (sip->si_flags & SI_COLL) {
 		nselcoll++;
 		sip->si_flags &= ~SI_COLL;
 		wakeup(&selwait);
 	}
-	p = pfind(sip->si_selpid);
-	sip->si_selpid = 0;
+	p = pfind(sip->si_seltid);
+	sip->si_seltid = 0;
 	if (p != NULL) {
 		SCHED_LOCK(s);
 		if (p->p_wchan == (caddr_t)&selwait) {
diff --git a/sys/kern/sys_process.c b/sys/kern/sys_process.c
index b295908c122..7c7b261cba3 100644
--- a/sys/kern/sys_process.c
+++ b/sys/kern/sys_process.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sys_process.c,v 1.73 2016/10/19 08:31:33 guenther Exp $	*/
+/*	$OpenBSD: sys_process.c,v 1.74 2016/11/07 00:26:33 guenther Exp $	*/
 /*	$NetBSD: sys_process.c,v 1.55 1996/05/15 06:17:47 tls Exp $	*/
 
 /*-
@@ -109,6 +109,7 @@ sys_ptrace(struct proc *p, void *v, register_t *retval)
 	switch (req) {
 	case PT_TRACE_ME:
 		t = p;
+		tr = t->p_p;
 		break;
 
 	/* calls that only operate on the PID */
@@ -124,20 +125,22 @@ sys_ptrace(struct proc *p, void *v, register_t *retval)
 	case PT_GET_PROCESS_STATE:
 	case PT_GET_THREAD_FIRST:
 	case PT_GET_THREAD_NEXT:
+	case PT_DETACH:
 	default:
 		/* Find the process we're supposed to be operating on. */
-		if ((t = pfind(SCARG(uap, pid))) == NULL)
-			return (ESRCH);
-		if (t->p_flag & P_THREAD)
+		if ((tr = prfind(SCARG(uap, pid))) == NULL)
 			return (ESRCH);
+		t = tr->ps_mainproc;	/* XXX */
 		break;
 
 	/* calls that accept a PID or a thread ID */
 	case PT_CONTINUE:
-	case PT_DETACH:
 #ifdef PT_STEP
 	case PT_STEP:
 #endif
+#ifdef PT_WCOOKIE
+	case PT_WCOOKIE:
+#endif
 	case PT_GETREGS:
 	case PT_SETREGS:
 #ifdef PT_GETFPREGS
@@ -156,15 +159,14 @@ sys_ptrace(struct proc *p, void *v, register_t *retval)
 			t = pfind(SCARG(uap, pid) - THREAD_PID_OFFSET);
 			if (t == NULL)
 				return (ESRCH);
+			tr = t->p_p;
 		} else {
-			if ((t = pfind(SCARG(uap, pid))) == NULL)
-				return (ESRCH);
-			if (t->p_flag & P_THREAD)
+			if ((tr = prfind(SCARG(uap, pid))) == NULL)
 				return (ESRCH);
+			t = tr->ps_mainproc;	/* XXX */
 		}
 		break;
 	}
-	tr = t->p_p;
 
 	if ((tr->ps_flags & PS_INEXEC) != 0)
 		return (EAGAIN);
@@ -327,7 +329,7 @@ sys_ptrace(struct proc *p, void *v, register_t *retval)
 		if (t == NULL)
 			pts.pts_tid = -1;
 		else
-			pts.pts_tid = t->p_pid + THREAD_PID_OFFSET;
+			pts.pts_tid = t->p_tid + THREAD_PID_OFFSET;
 		return (copyout(&pts, SCARG(uap, addr), sizeof(pts)));
 
 	default:			/* It was not a legal request. */
@@ -571,7 +573,7 @@ sys_ptrace(struct proc *p, void *v, register_t *retval)
 
 		if (tr->ps_single)
 			tr->ps_ptstat->pe_tid =
-			    tr->ps_single->p_pid + THREAD_PID_OFFSET;
+			    tr->ps_single->p_tid + THREAD_PID_OFFSET;
 
 		return (copyout(tr->ps_ptstat, SCARG(uap, addr),
 		    sizeof(*tr->ps_ptstat)));
diff --git a/sys/kern/vfs_lockf.c b/sys/kern/vfs_lockf.c
index 6ced82196a4..019090005be 100644
--- a/sys/kern/vfs_lockf.c
+++ b/sys/kern/vfs_lockf.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vfs_lockf.c,v 1.23 2016/09/15 02:00:16 dlg Exp $	*/
+/*	$OpenBSD: vfs_lockf.c,v 1.24 2016/11/07 00:26:33 guenther Exp $	*/
 /*	$NetBSD: vfs_lockf.c,v 1.7 1996/02/04 02:18:21 christos Exp $	*/
 
 /*
@@ -693,7 +693,7 @@ lf_print(char *tag, struct lockf *lock)
 	
 	printf("%s: lock %p for ", tag, lock);
 	if (lock->lf_flags & F_POSIX)
-		printf("proc %d", ((struct proc *)(lock->lf_id))->p_pid);
+		printf("thread %d", ((struct proc *)(lock->lf_id))->p_tid);
 	else
 		printf("id %p", lock->lf_id);
 	printf(" %s, start %llx, end %llx",
@@ -719,7 +719,7 @@ lf_printlist(char *tag, struct lockf *lock)
 	for (lf = *lock->lf_head; lf; lf = lf->lf_next) {
 		printf("\tlock %p for ", lf);
 		if (lf->lf_flags & F_POSIX)
-			printf("proc %d", ((struct proc*)(lf->lf_id))->p_pid);
+			printf("thread %d", ((struct proc*)(lf->lf_id))->p_tid);
 		else
 			printf("id %p", lf->lf_id);
 		printf(" %s, start %llx, end %llx",
diff --git a/sys/sys/proc.h b/sys/sys/proc.h
index 13669b469ea..6227ed78de1 100644
--- a/sys/sys/proc.h
+++ b/sys/sys/proc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: proc.h,v 1.226 2016/09/03 08:47:24 tedu Exp $	*/
+/*	$OpenBSD: proc.h,v 1.227 2016/11/07 00:26:32 guenther Exp $	*/
 /*	$NetBSD: proc.h,v 1.44 1996/04/22 01:23:21 christos Exp $	*/
 
 /*-
@@ -168,11 +168,13 @@ struct process {
 	struct	process *ps_pptr; 	/* Pointer to parent process. */
 	LIST_ENTRY(process) ps_sibling;	/* List of sibling processes. */
 	LIST_HEAD(, process) ps_children;/* Pointer to list of children. */
+	LIST_ENTRY(process) ps_hash;    /* Hash chain. */
 
 	struct	sigacts *ps_sigacts;	/* Signal actions, state */
 	struct	vnode *ps_textvp;	/* Vnode of executable. */
 	struct	filedesc *ps_fd;	/* Ptr to open files structure */
 	struct	vmspace *ps_vmspace;	/* Address space */
+	pid_t	ps_pid;			/* Process identifier. */
 
 /* The following fields are all zeroed upon creation in process_new. */
 #define	ps_startzero	ps_klist
@@ -236,7 +238,6 @@ struct process {
 	struct	timeout ps_realit_to;	/* real-time itimer trampoline. */
 };
 
-#define	ps_pid		ps_mainproc->p_pid
 #define	ps_session	ps_pgrp->pg_session
 #define	ps_pgid		ps_pgrp->pg_id
 
@@ -294,7 +295,7 @@ struct proc {
 	char	p_pad1[1];
 	u_char	p_descfd;		/* if not 255, fdesc permits this fd */
 
-	pid_t	p_pid;			/* Process identifier. */
+	pid_t	p_tid;			/* Thread identifier. */
 	LIST_ENTRY(proc) p_hash;	/* Hash chain. */
 
 /* The following fields are all zeroed upon creation in fork. */
@@ -403,7 +404,7 @@ struct proc {
      "\016WEXIT" "\020OWEUPC" "\024SUSPSINGLE" "\027XX" \
      "\030CONTINUED" "\033THREAD" "\034SUSPSIG" "\035SOFTDEP" "\037CPUPEG")
 
-#define	THREAD_PID_OFFSET	1000000
+#define	THREAD_PID_OFFSET	100000
 
 #ifdef _KERNEL
 
@@ -420,8 +421,15 @@ struct uidinfo *uid_find(uid_t);
  * We use process IDs <= PID_MAX; PID_MAX + 1 must also fit in a pid_t,
  * as it is used to represent "no process group".
  * We set PID_MAX to 99999 to keep it in 5 columns in ps
+ * When exposed to userspace, thread IDs have THREAD_PID_OFFSET
+ * added to keep them from overlapping the PID range.  For them,
+ * we use a * a (0 .. 2^n] range for cheapness, picking 'n' such
+ * that 2^n + THREAD_PID_OFFSET and THREAD_PID_OFFSET have
+ * the same number of columns when printed.
  */
-#define	PID_MAX		99999
+#define	PID_MAX			99999
+#define	TID_MASK		0x7ffff
+
 #define	NO_PID		(PID_MAX+1)
 
 #define SESS_LEADER(pr)	((pr)->ps_session->s_leader == (pr))
@@ -453,8 +461,12 @@ struct uidinfo *uid_find(uid_t);
 #define EXIT_THREAD		0x00000002
 #define EXIT_THREAD_NOCHECK	0x00000003
 
+#define	TIDHASH(tid)	(&tidhashtbl[(tid) & tidhash])
+extern LIST_HEAD(tidhashhead, proc) *tidhashtbl;
+extern u_long tidhash;
+
 #define	PIDHASH(pid)	(&pidhashtbl[(pid) & pidhash])
-extern LIST_HEAD(pidhashhead, proc) *pidhashtbl;
+extern LIST_HEAD(pidhashhead, process) *pidhashtbl;
 extern u_long pidhash;
 
 #define	PGRPHASH(pgid)	(&pgrphashtbl[(pgid) & pgrphash])
@@ -484,8 +496,6 @@ extern struct pool ucred_pool;		/* memory pool for ucreds */
 extern struct pool session_pool;	/* memory pool for sessions */
 extern struct pool pgrp_pool;		/* memory pool for pgrps */
 
-int	ispidtaken(pid_t);
-pid_t	allocpid(void);
 void	freepid(pid_t);
 
 struct process *prfind(pid_t);	/* Find process by id. */
diff --git a/sys/sys/selinfo.h b/sys/sys/selinfo.h
index b65a98db301..8235c8c0944 100644
--- a/sys/sys/selinfo.h
+++ b/sys/sys/selinfo.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: selinfo.h,v 1.3 2007/07/25 23:11:53 art Exp $	*/
+/*	$OpenBSD: selinfo.h,v 1.4 2016/11/07 00:26:32 guenther Exp $	*/
 
 /*-
  * Copyright (c) 1992, 1993
@@ -41,7 +41,7 @@
  * notified when I/O becomes possible.
  */
 struct selinfo {
-	pid_t	si_selpid;	/* process to be notified */
+	pid_t	si_seltid;	/* thread to be notified */
 	struct	klist si_note;	/* kernel note list */
 	short	si_flags;	/* see below */
 };
diff --git a/sys/sys/sysctl.h b/sys/sys/sysctl.h
index 53137675420..b701311df72 100644
--- a/sys/sys/sysctl.h
+++ b/sys/sys/sysctl.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sysctl.h,v 1.169 2016/10/07 19:04:44 tedu Exp $	*/
+/*	$OpenBSD: sysctl.h,v 1.170 2016/11/07 00:26:32 guenther Exp $	*/
 /*	$NetBSD: sysctl.h,v 1.16 1996/04/09 20:55:36 cgd Exp $	*/
 
 /*
@@ -494,12 +494,13 @@ struct kinfo_vmentry {
  *	uc - source struct ucreds
  *	pg - source struct pgrp
  *	paddr - kernel address of the source struct proc
+ *	praddr - kernel address of the source struct process
  *	sess - source struct session
  *	vm - source struct vmspace
  *	lim - source struct plimits
  *	sa - source struct sigacts
  * There are some members that are not handled by these macros
- * because they're too painful to generalize: p_pid, p_ppid, p_sid, p_tdev,
+ * because they're too painful to generalize: p_ppid, p_sid, p_tdev,
  * p_tpgid, p_tsess, p_vm_rssize, p_u[us]time_{sec,usec}, p_cpuid
  */
 
@@ -522,6 +523,7 @@ do {									\
 	(kp)->p_stats = 0;						\
 	(kp)->p_exitsig = 0;						\
 	(kp)->p_flag = (p)->p_flag;					\
+	(kp)->p_pid = (pr)->ps_pid;					\
 	(kp)->p_psflags = (pr)->ps_flags;				\
 									\
 	(kp)->p__pgid = (pg)->pg_id;					\
@@ -543,7 +545,7 @@ do {									\
 	if (isthread) {							\
 		(kp)->p_rtime_sec = (p)->p_tu.tu_runtime.tv_sec;	\
 		(kp)->p_rtime_usec = (p)->p_tu.tu_runtime.tv_nsec/1000;	\
-		(kp)->p_tid = (p)->p_pid + THREAD_PID_OFFSET;		\
+		(kp)->p_tid = (p)->p_tid + THREAD_PID_OFFSET;		\
 		(kp)->p_uticks = (p)->p_tu.tu_uticks;			\
 		(kp)->p_sticks = (p)->p_tu.tu_sticks;			\
 		(kp)->p_iticks = (p)->p_tu.tu_iticks;			\
diff --git a/sys/ufs/ffs/ffs_softdep.c b/sys/ufs/ffs/ffs_softdep.c
index 6af3dbbe1c3..0c9e10c1052 100644
--- a/sys/ufs/ffs/ffs_softdep.c
+++ b/sys/ufs/ffs/ffs_softdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ffs_softdep.c,v 1.134 2016/09/15 02:00:18 dlg Exp $	*/
+/*	$OpenBSD: ffs_softdep.c,v 1.135 2016/11/07 00:26:33 guenther Exp $	*/
 
 /*
  * Copyright 1998, 2000 Marshall Kirk McKusick. All Rights Reserved.
@@ -227,13 +227,13 @@ acquire_lock(struct lockit *lk, int line)
 		holder = lk->lkt_held;
 		original_line = lk->lkt_line;
 		FREE_LOCK(lk);
-		if (holder == CURPROC->p_pid)
+		if (holder == CURPROC->p_tid)
 			panic("softdep_lock: locking against myself, acquired at line %d, relocked at line %d", original_line, line);
 		else
 			panic("softdep_lock: lock held by %d, acquired at line %d, relocked at line %d", holder, original_line, line);
 	}
 	lk->lkt_spl = splbio();
-	lk->lkt_held = CURPROC->p_pid;
+	lk->lkt_held = CURPROC->p_tid;
 	lk->lkt_line = line;
 	lockcnt++;
 }
@@ -258,12 +258,12 @@ acquire_lock_interlocked(struct lockit *lk, int s, int line)
 		holder = lk->lkt_held;
 		original_line = lk->lkt_line;
 		FREE_LOCK_INTERLOCKED(lk);
-		if (holder == CURPROC->p_pid)
+		if (holder == CURPROC->p_tid)
 			panic("softdep_lock: locking against myself, acquired at line %d, relocked at line %d", original_line, line);
 		else
 			panic("softdep_lock: lock held by %d, acquired at line %d, relocked at line %d", holder, original_line, line);
 	}
-	lk->lkt_held = CURPROC->p_pid;
+	lk->lkt_held = CURPROC->p_tid;
 	lk->lkt_line = line;
 	lk->lkt_spl = s;
 	lockcnt++;
@@ -321,7 +321,7 @@ sema_get(struct sema *semap, struct lockit *interlock)
 		}
 		return (0);
 	}
-	semap->holder = CURPROC->p_pid;
+	semap->holder = CURPROC->p_tid;
 	if (interlock != NULL)
 		FREE_LOCK(interlock);
 	return (1);
@@ -331,7 +331,7 @@ STATIC void
 sema_release(struct sema *semap)
 {
 
-	if (semap->value <= 0 || semap->holder != CURPROC->p_pid) {
+	if (semap->value <= 0 || semap->holder != CURPROC->p_tid) {
 #ifdef DEBUG
 		if (lk.lkt_held != -1)
 			FREE_LOCK(&lk);
diff --git a/sys/ufs/mfs/mfs_vfsops.c b/sys/ufs/mfs/mfs_vfsops.c
index 73fa6448e9f..1d7f7c9db0a 100644
--- a/sys/ufs/mfs/mfs_vfsops.c
+++ b/sys/ufs/mfs/mfs_vfsops.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mfs_vfsops.c,v 1.52 2016/09/08 16:57:29 tedu Exp $	*/
+/*	$OpenBSD: mfs_vfsops.c,v 1.53 2016/11/07 00:26:33 guenther Exp $	*/
 /*	$NetBSD: mfs_vfsops.c,v 1.10 1996/02/09 22:31:28 christos Exp $	*/
 
 /*
@@ -135,7 +135,7 @@ mfs_mount(struct mount *mp, const char *path, void *data,
 	mfsp->mfs_baseoff = args.base;
 	mfsp->mfs_size = args.size;
 	mfsp->mfs_vnode = devvp;
-	mfsp->mfs_pid = p->p_pid;
+	mfsp->mfs_tid = p->p_tid;
 	bufq_init(&mfsp->mfs_bufq, BUFQ_FIFO);
 	if ((error = ffs_mountfs(devvp, mp, p)) != 0) {
 		mfsp->mfs_shutdown = 1;
diff --git a/sys/ufs/mfs/mfs_vnops.c b/sys/ufs/mfs/mfs_vnops.c
index dfae239885f..94faf2ea743 100644
--- a/sys/ufs/mfs/mfs_vnops.c
+++ b/sys/ufs/mfs/mfs_vnops.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mfs_vnops.c,v 1.48 2016/09/08 16:44:46 tedu Exp $	*/
+/*	$OpenBSD: mfs_vnops.c,v 1.49 2016/11/07 00:26:33 guenther Exp $	*/
 /*	$NetBSD: mfs_vnops.c,v 1.8 1996/03/17 02:16:32 christos Exp $	*/
 
 /*
@@ -130,7 +130,7 @@ mfs_strategy(void *v)
 		panic("mfs_strategy: bad dev");
 
 	mfsp = VTOMFS(vp);
-	if (p != NULL && mfsp->mfs_pid == p->p_pid) {
+	if (p != NULL && mfsp->mfs_tid == p->p_tid) {
 		mfs_doio(mfsp, bp);
 	} else {
 		bufq_queue(&mfsp->mfs_bufq, bp);
@@ -252,7 +252,7 @@ mfs_print(void *v)
 	struct vop_print_args *ap = v;
 	struct mfsnode *mfsp = VTOMFS(ap->a_vp);
 
-	printf("tag VT_MFS, pid %d, base %p, size %ld\n", mfsp->mfs_pid,
+	printf("tag VT_MFS, tid %d, base %p, size %ld\n", mfsp->mfs_tid,
 	    mfsp->mfs_baseoff, mfsp->mfs_size);
 	return (0);
 }
diff --git a/sys/ufs/mfs/mfsnode.h b/sys/ufs/mfs/mfsnode.h
index 644c72a2e8e..f57db08e694 100644
--- a/sys/ufs/mfs/mfsnode.h
+++ b/sys/ufs/mfs/mfsnode.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mfsnode.h,v 1.14 2013/01/15 11:20:55 jsing Exp $	*/
+/*	$OpenBSD: mfsnode.h,v 1.15 2016/11/07 00:26:33 guenther Exp $	*/
 /*	$NetBSD: mfsnode.h,v 1.3 1996/02/09 22:31:31 christos Exp $	*/
 
 /*
@@ -41,7 +41,7 @@ struct mfsnode {
 	struct bufq mfs_bufq;		/* bufq for MFS I/O */
 	caddr_t	mfs_baseoff;		/* base of file system in memory */
 	long	mfs_size;		/* size of memory file system */
-	pid_t	mfs_pid;		/* supporting process pid */
+	pid_t	mfs_tid;		/* supporting thread's tid */
 	struct	buf *mfs_buflist;	/* list of I/O requests */
 	int	mfs_shutdown;		/* shutdown request */
 };
diff --git a/sys/uvm/uvm_map.c b/sys/uvm/uvm_map.c
index 7b3a51cd1af..10a9ab0601a 100644
--- a/sys/uvm/uvm_map.c
+++ b/sys/uvm/uvm_map.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_map.c,v 1.225 2016/09/16 02:35:42 dlg Exp $	*/
+/*	$OpenBSD: uvm_map.c,v 1.226 2016/11/07 00:26:33 guenther Exp $	*/
 /*	$NetBSD: uvm_map.c,v 1.86 2000/11/27 08:40:03 chs Exp $	*/
 
 /*
@@ -2951,7 +2951,7 @@ uvm_page_printit(pg, full, pr)
 	    pg->uobject, pg->uanon, (long long)pg->offset);
 #if defined(UVM_PAGE_TRKOWN)
 	if (pg->pg_flags & PG_BUSY)
-		(*pr)("  owning process = %d, tag=%s",
+		(*pr)("  owning thread = %d, tag=%s",
 		    pg->owner, pg->owner_tag);
 	else
 		(*pr)("  page not busy, no owner");
diff --git a/sys/uvm/uvm_page.c b/sys/uvm/uvm_page.c
index 24a150c859f..4002c61dfad 100644
--- a/sys/uvm/uvm_page.c
+++ b/sys/uvm/uvm_page.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_page.c,v 1.145 2016/09/16 02:35:42 dlg Exp $	*/
+/*	$OpenBSD: uvm_page.c,v 1.146 2016/11/07 00:26:33 guenther Exp $	*/
 /*	$NetBSD: uvm_page.c,v 1.44 2000/11/27 08:40:04 chs Exp $	*/
 
 /*
@@ -1077,7 +1077,7 @@ uvm_page_unbusy(struct vm_page **pgs, int npgs)
  *
  * => this is a debugging function that keeps track of who sets PG_BUSY
  *	and where they do it.   it can be used to track down problems
- *	such a process setting "PG_BUSY" and never releasing it.
+ *	such a thread setting "PG_BUSY" and never releasing it.
  * => if "tag" is NULL then we are releasing page ownership
  */
 void
@@ -1087,11 +1087,11 @@ uvm_page_own(struct vm_page *pg, char *tag)
 	if (tag) {
 		if (pg->owner_tag) {
 			printf("uvm_page_own: page %p already owned "
-			    "by proc %d [%s]\n", pg,
+			    "by thread %d [%s]\n", pg,
 			     pg->owner, pg->owner_tag);
 			panic("uvm_page_own");
 		}
-		pg->owner = (curproc) ? curproc->p_pid :  (pid_t) -1;
+		pg->owner = (curproc) ? curproc->p_tid :  (pid_t) -1;
 		pg->owner_tag = tag;
 		return;
 	}
diff --git a/sys/uvm/uvm_page.h b/sys/uvm/uvm_page.h
index ca1fc255d3c..6ea58655b01 100644
--- a/sys/uvm/uvm_page.h
+++ b/sys/uvm/uvm_page.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_page.h,v 1.62 2016/09/16 02:35:42 dlg Exp $	*/
+/*	$OpenBSD: uvm_page.h,v 1.63 2016/11/07 00:26:33 guenther Exp $	*/
 /*	$NetBSD: uvm_page.h,v 1.19 2000/12/28 08:24:55 chs Exp $	*/
 
 /* 
@@ -112,7 +112,7 @@ struct vm_page {
 
 #if defined(UVM_PAGE_TRKOWN)
 	/* debugging fields to track page ownership */
-	pid_t			owner;		/* proc that set PG_BUSY */
+	pid_t			owner;		/* thread that set PG_BUSY */
 	char			*owner_tag;	/* why it was set busy */
 #endif
 };