Module Name: src
Committed By: riastradh
Date: Sun Apr 7 22:59:13 UTC 2024
Modified Files:
src/sys/arch/riscv/riscv: clock_machdep.c
Log Message:
riscv: Schedule next hardclock tick in the future, not the past.
If we have missed hardclock ticks, schedule up to one tick interval
in the future anyway; don't try to play hardclock catchup by
scheduling for when the next hardclock tick _should_ have been, in
the past, leading to ticking as fast as possible until we've caught
up. as fast as possible until we've caught up.
Playing hardclock catchup triggers heartbeat panics when continuing
from ddb, if you've been in ddb for >15sec. Other hardclock drivers
like x86 lapic don't play hardclock catchup either.
PR kern/57920
To generate a diff of this commit:
cvs rdiff -u -r1.7 -r1.8 src/sys/arch/riscv/riscv/clock_machdep.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/riscv/riscv/clock_machdep.c
diff -u src/sys/arch/riscv/riscv/clock_machdep.c:1.7 src/sys/arch/riscv/riscv/clock_machdep.c:1.8
--- src/sys/arch/riscv/riscv/clock_machdep.c:1.7 Thu Jan 18 07:41:50 2024
+++ src/sys/arch/riscv/riscv/clock_machdep.c Sun Apr 7 22:59:13 2024
@@ -1,4 +1,4 @@
-/* $NetBSD: clock_machdep.c,v 1.7 2024/01/18 07:41:50 skrll Exp $ */
+/* $NetBSD: clock_machdep.c,v 1.8 2024/04/07 22:59:13 riastradh Exp $ */
/*-
* Copyright (c) 2014 The NetBSD Foundation, Inc.
@@ -31,7 +31,7 @@
#include <sys/cdefs.h>
-__RCSID("$NetBSD: clock_machdep.c,v 1.7 2024/01/18 07:41:50 skrll Exp $");
+__RCSID("$NetBSD: clock_machdep.c,v 1.8 2024/04/07 22:59:13 riastradh Exp $");
#include <sys/param.h>
#include <sys/cpu.h>
@@ -124,6 +124,10 @@ riscv_timer_intr(void *arg)
ci->ci_ev_timer.ev_count++;
ci->ci_lastintr_scheduled += timer_ticks_per_hz;
+ while (__predict_false(ci->ci_lastintr_scheduled < now)) {
+ ci->ci_lastintr_scheduled += timer_ticks_per_hz;
+ /* XXX count missed timer interrupts */
+ }
sbi_set_timer(ci->ci_lastintr_scheduled);
hardclock(cf);
