[src/trunk]: src/sys/kern heartbeat(9): For now, use time_uptime without atom...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/0bcd7214b9be
branches:  trunk
changeset: 377537:0bcd7214b9be
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sun Jul 16 10:18:19 2023 +0000

description:
heartbeat(9): For now, use time_uptime without atomic_load_relaxed.

A later commit will change time_uptime to a macro so it is atomic,
using atomc_load_relaxed if possible or seqlock if not.

diffstat:

 sys/kern/kern_heartbeat.c |  10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)

diffs (45 lines):

diff -r fea334b7efb1 -r 0bcd7214b9be sys/kern/kern_heartbeat.c
--- a/sys/kern/kern_heartbeat.c Sun Jul 16 10:18:07 2023 +0000
+++ b/sys/kern/kern_heartbeat.c Sun Jul 16 10:18:19 2023 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_heartbeat.c,v 1.4 2023/07/16 10:18:07 riastradh Exp $     */
+/*     $NetBSD: kern_heartbeat.c,v 1.5 2023/07/16 10:18:19 riastradh Exp $     */
 
 /*-
  * Copyright (c) 2023 The NetBSD Foundation, Inc.
@@ -78,7 +78,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_heartbeat.c,v 1.4 2023/07/16 10:18:07 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_heartbeat.c,v 1.5 2023/07/16 10:18:19 riastradh Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_ddb.h"
@@ -157,7 +157,7 @@ heartbeat_resume_cpu(struct cpu_info *ci
        KASSERT(__predict_false(cold) || ci == curcpu());
 
        ci->ci_heartbeat_count = 0;
-       ci->ci_heartbeat_uptime_cache = atomic_load_relaxed(&time_uptime);
+       ci->ci_heartbeat_uptime_cache = time_uptime;
        ci->ci_heartbeat_uptime_stamp = 0;
 }
 
@@ -352,7 +352,7 @@ static void
 heartbeat_intr(void *cookie)
 {
        unsigned count = atomic_load_relaxed(&curcpu()->ci_heartbeat_count);
-       unsigned uptime = atomic_load_relaxed(&time_uptime);
+       unsigned uptime = time_uptime;
 
        atomic_store_relaxed(&curcpu()->ci_heartbeat_uptime_stamp, count);
        atomic_store_relaxed(&curcpu()->ci_heartbeat_uptime_cache, uptime);
@@ -579,7 +579,7 @@ heartbeat(void)
         * changed, and stop here -- we only do the cross-CPU work once
         * per second.
         */
-       uptime = atomic_load_relaxed(&time_uptime);
+       uptime = time_uptime;
        cache = atomic_load_relaxed(&curcpu()->ci_heartbeat_uptime_cache);
        if (__predict_true(cache == uptime)) {
                /*