Delete tests for P_THREAD that predate the existence of

KERN_PROC_SHOW_THREADS and have been rendered superfluous by it.
Similarly, some P_SYSTEM tests can be deleted or pushed to the
kernel by using KERN_PROC_ALL instead of KERN_PROC_KTHREAD.

ok visa@ mpi@

bin/ps/ps.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: ps.c,v 1.75 2019/03/24 05:30:35 deraadt Exp $	*/
+/*	$OpenBSD: ps.c,v 1.76 2019/12/16 19:21:16 guenther Exp $	*/
 /*	$NetBSD: ps.c,v 1.15 1995/05/18 20:33:25 mycroft Exp $	*/
 
 /*-
@@ -361,8 +361,6 @@ main(int argc, char *argv[])
 	 * for each proc, call each variable output function.
 	 */
 	for (i = lineno = 0; i < nentries; i++) {
-		if (showthreads == 0 && (kinfo[i]->p_flag & P_THREAD) != 0)
-			continue;
 		if (xflg == 0 && ((int)kinfo[i]->p_tdev == NODEV ||
 		    (kinfo[i]->p_psflags & PS_CONTROLT ) == 0))
 			continue;

usr.bin/pkill/pkill.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: pkill.c,v 1.41 2019/06/28 13:35:02 deraadt Exp $	*/
+/*	$OpenBSD: pkill.c,v 1.42 2019/12/16 19:21:17 guenther Exp $	*/
 /*	$NetBSD: pkill.c,v 1.5 2002/10/27 11:49:34 kleink Exp $	*/
 
 /*-
@@ -297,8 +297,7 @@ main(int argc, char **argv)
 		}
 
 		for (i = 0, kp = plist; i < nproc; i++, kp++) {
-			if ((kp->p_flag & (P_SYSTEM | P_THREAD)) != 0 ||
-			     kp->p_pid == mypid)
+			if (kp->p_pid == mypid)
 				continue;
 
 			if (matchargs)
@@ -324,8 +323,7 @@ main(int argc, char **argv)
 	}
 
 	for (i = 0, kp = plist; i < nproc; i++, kp++) {
-		if ((kp->p_flag & (P_SYSTEM | P_THREAD)) != 0 ||
-		     kp->p_pid == mypid)
+		if (kp->p_pid == mypid)
 			continue;
 
 		SLIST_FOREACH(li, &ruidlist, li_chain)
@@ -435,8 +433,7 @@ main(int argc, char **argv)
 	 */
 	rv = STATUS_NOMATCH;
 	for (i = 0, j = 0, kp = plist; i < nproc; i++, kp++) {
-		if ((kp->p_flag & (P_SYSTEM | P_THREAD)) != 0 ||
-		     kp->p_pid == mypid)
+		if (kp->p_pid == mypid)
 			continue;
 		if (selected[i] == inverse)
 			continue;

usr.bin/top/machine.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: machine.c,v 1.100 2019/10/08 20:51:03 kn Exp $	 */
+/* $OpenBSD: machine.c,v 1.101 2019/12/16 19:21:17 guenther Exp $	 */
 
 /*-
  * Copyright (c) 1994 Thorsten Lockert <tholo@sigmasoft.com>
@@ -427,9 +427,14 @@ get_process_info(struct system_info *si, struct process_select *sel,
 	int hide_uid;
 	int total_procs, active_procs;
 	struct kinfo_proc **prefp, *pp;
-	int what = KERN_PROC_KTHREAD;
+	int what = KERN_PROC_ALL;
 
-	if (sel->threads)
+	show_system = sel->system;
+	show_threads = sel->threads;
+
+	if (show_system)
+		what = KERN_PROC_KTHREAD;
+	if (show_threads)
 		what |= KERN_PROC_SHOW_THREADS;
 
 	if ((pbase = getprocs(what, 0, &nproc)) == NULL) {
@@ -448,8 +453,6 @@ get_process_info(struct system_info *si, struct process_select *sel,
 
 	/* set up flags which define what we are going to select */
 	show_idle = sel->idle;
-	show_system = sel->system;
-	show_threads = sel->threads;
 	show_uid = sel->uid != (uid_t)-1;
 	hide_uid = sel->huid != (uid_t)-1;
 	show_pid = sel->pid != (pid_t)-1;
@@ -462,16 +465,17 @@ get_process_info(struct system_info *si, struct process_select *sel,
 	prefp = pref;
 	for (pp = pbase; pp < &pbase[nproc]; pp++) {
 		/*
-		 *  Place pointers to each valid proc structure in pref[].
-		 *  Process slots that are actually in use have a non-zero
-		 *  status field.  Processes with P_SYSTEM set are system
-		 *  processes---these get ignored unless show_system is set.
+		 * When showing threads, we want to ignore the structure
+		 * that represents the entire process, which has TID == -1
 		 */
 		if (show_threads && pp->p_tid == -1)
 			continue;
-		if (pp->p_stat != 0 &&
-		    (show_system || (pp->p_flag & P_SYSTEM) == 0) &&
-		    (show_threads || (pp->p_flag & P_THREAD) == 0)) {
+		/*
+		 * Place pointers to each valid proc structure in pref[].
+		 * Process slots that are actually in use have a non-zero
+		 * status field.
+		 */
+		if (pp->p_stat != 0) {
 			total_procs++;
 			process_states[(unsigned char) pp->p_stat]++;
 			if ((pp->p_psflags & PS_ZOMBIE) == 0 &&