timeout(9): remove TIMEOUT_SCHEDULED flag

The TIMEOUT_SCHEDULED flag was added a few months ago to differentiate
between wheel timeouts and new timeouts during softclock().  The
distinction is useful when incrementing the "rescheduled" stat and the
"late" stat.

Now that we have an intermediate queue for new timeouts, timeout_new,
we don't need the flag.  The distinction between wheel timeouts and
new timeouts can be made computationally.

Suggested by procter@ several months ago.

2 files changed, 17 insertions, 13 deletions

diff --git a/sys/kern/kern_timeout.c b/sys/kern/kern_timeout.c
index aecf49b6dab..6a75c724d8f 100644
--- a/sys/kern/kern_timeout.c
+++ b/sys/kern/kern_timeout.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_timeout.c,v 1.75 2020/07/24 21:01:33 cheloha Exp $	*/
+/*	$OpenBSD: kern_timeout.c,v 1.76 2020/07/25 00:48:04 cheloha Exp $	*/
 /*
  * Copyright (c) 2001 Thomas Nordin <nordin@openbsd.org>
  * Copyright (c) 2000-2001 Artur Grabowski <art@openbsd.org>
@@ -258,7 +258,7 @@ timeout_add(struct timeout *new, int to_ticks)
 	/* Initialize the time here, it won't change. */
 	old_time = new->to_time;
 	new->to_time = to_ticks + ticks;
-	CLR(new->to_flags, TIMEOUT_TRIGGERED | TIMEOUT_SCHEDULED);
+	CLR(new->to_flags, TIMEOUT_TRIGGERED);
 
 	/*
 	 * If this timeout already is scheduled and now is moved
@@ -387,7 +387,7 @@ timeout_del(struct timeout *to)
 		tostat.tos_cancelled++;
 		ret = 1;
 	}
-	CLR(to->to_flags, TIMEOUT_TRIGGERED | TIMEOUT_SCHEDULED);
+	CLR(to->to_flags, TIMEOUT_TRIGGERED);
 	tostat.tos_deleted++;
 	mtx_leave(&timeout_mutex);
 
@@ -483,7 +483,7 @@ timeout_run(struct timeout *to)
 
 	MUTEX_ASSERT_LOCKED(&timeout_mutex);
 
-	CLR(to->to_flags, TIMEOUT_ONQUEUE | TIMEOUT_SCHEDULED);
+	CLR(to->to_flags, TIMEOUT_ONQUEUE);
 	SET(to->to_flags, TIMEOUT_TRIGGERED);
 
 	fn = to->to_func;
@@ -507,14 +507,21 @@ void
 softclock(void *arg)
 {
 	struct circq *bucket;
-	struct timeout *to;
-	int delta, needsproc;
+	struct timeout *first_new, *to;
+	int delta, needsproc, new;
+
+	first_new = NULL;
+	new = 0;
 
 	mtx_enter(&timeout_mutex);
+	if (!CIRCQ_EMPTY(&timeout_new))
+		first_new = timeout_from_circq(CIRCQ_FIRST(&timeout_new));
 	CIRCQ_CONCAT(&timeout_todo, &timeout_new);
 	while (!CIRCQ_EMPTY(&timeout_todo)) {
 		to = timeout_from_circq(CIRCQ_FIRST(&timeout_todo));
 		CIRCQ_REMOVE(&to->to_list);
+		if (to == first_new)
+			new = 1;
 
 		/*
 		 * If due run it or defer execution to the thread,
@@ -524,14 +531,12 @@ softclock(void *arg)
 		if (delta > 0) {
 			bucket = &BUCKET(delta, to->to_time);
 			CIRCQ_INSERT_TAIL(bucket, &to->to_list);
-			if (ISSET(to->to_flags, TIMEOUT_SCHEDULED))
-				tostat.tos_rescheduled++;
-			else
-				SET(to->to_flags, TIMEOUT_SCHEDULED);
 			tostat.tos_scheduled++;
+			if (!new)
+				tostat.tos_rescheduled++;
 			continue;
 		}
-		if (ISSET(to->to_flags, TIMEOUT_SCHEDULED) && delta < 0)
+		if (!new && delta < 0)
 			tostat.tos_late++;
 		if (ISSET(to->to_flags, TIMEOUT_PROC)) {
 			CIRCQ_INSERT_TAIL(&timeout_proc, &to->to_list);
diff --git a/sys/sys/timeout.h b/sys/sys/timeout.h
index 1cd9fca9e06..271605ca024 100644
--- a/sys/sys/timeout.h
+++ b/sys/sys/timeout.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: timeout.h,v 1.36 2020/01/03 02:16:38 cheloha Exp $	*/
+/*	$OpenBSD: timeout.h,v 1.37 2020/07/25 00:48:03 cheloha Exp $	*/
 /*
  * Copyright (c) 2000-2001 Artur Grabowski <art@openbsd.org>
  * All rights reserved. 
@@ -71,7 +71,6 @@ struct timeout {
 #define TIMEOUT_ONQUEUE		0x02	/* on any timeout queue */
 #define TIMEOUT_INITIALIZED	0x04	/* initialized */
 #define TIMEOUT_TRIGGERED	0x08	/* running or ran */
-#define TIMEOUT_SCHEDULED	0x10	/* put on wheel at least once */
 
 struct timeoutstat {
 	uint64_t tos_added;		/* timeout_add*(9) calls */