amd64: switch to clockintr(9)

Switch amd64 to the clockintr(9) subsystem.  There are lots of little
changes, but the bigs ones are listed here.

When using the local apic timer:

- Run the timer in one-shot mode.
- lapic_delay() is gone.  We can't use it to delay(9) when running
  the timer in one-shot mode.
- Add a randomized statclock(); stathz = hz.
- Add support for switching to profhz when profiling is enabled;
  profhz = stathz * 10.

When using the i8254/mc146818:

- i8254's clockintr() no longer has a monopoly on hardclock().
- mc146818's rtcintr() no longer has a monopoly on statclock().
- In profiling mode, the statclock() will drift very slightly
  because (profhz = 1024) does not divide evenly into one billion.
  We could avoid this by setting (profhz = 512) instead and
  programming the RTC to run at that rate.

Early revisions reviewed by mlarkin@.  Extensively tested by mlarkin@
on a variety of physical and virtual hardware.  Additional testing
from dv@ and jmc@.

Link: https://marc.info/?l=openbsd-tech&m=166776339203279&w=2

ok kettenis@ mlarkin@

2 files changed, 7 insertions, 2 deletions

diff --git a/sys/arch/amd64/include/_types.h b/sys/arch/amd64/include/_types.h
index 67c67a1472f..a9445bb4d93 100644
--- a/sys/arch/amd64/include/_types.h
+++ b/sys/arch/amd64/include/_types.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: _types.h,v 1.17 2018/03/05 01:15:25 deraadt Exp $	*/
+/*	$OpenBSD: _types.h,v 1.18 2022/11/08 17:34:13 cheloha Exp $	*/
 
 /*-
  * Copyright (c) 1990, 1993
@@ -35,6 +35,8 @@
 #ifndef _MACHINE__TYPES_H_
 #define _MACHINE__TYPES_H_
 
+#define	__HAVE_CLOCKINTR
+
 /*
  * _ALIGN(p) rounds p (pointer or byte index) up to a correctly-aligned
  * value for all data types (int, long, ...).   The result is an
diff --git a/sys/arch/amd64/include/cpu.h b/sys/arch/amd64/include/cpu.h
index d5ce2f5d717..7dcbc82be11 100644
--- a/sys/arch/amd64/include/cpu.h
+++ b/sys/arch/amd64/include/cpu.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cpu.h,v 1.152 2022/11/08 14:46:51 cheloha Exp $	*/
+/*	$OpenBSD: cpu.h,v 1.153 2022/11/08 17:34:13 cheloha Exp $	*/
 /*	$NetBSD: cpu.h,v 1.1 2003/04/26 18:39:39 fvdl Exp $	*/
 
 /*-
@@ -47,6 +47,7 @@
 #include <machine/intrdefs.h>
 #endif /* _KERNEL */
 
+#include <sys/clockintr.h>
 #include <sys/device.h>
 #include <sys/rwlock.h>
 #include <sys/sched.h>
@@ -221,6 +222,8 @@ struct cpu_info {
 
 	paddr_t		ci_vmcs_pa;
 	struct rwlock	ci_vmcs_lock;
+
+	struct clockintr_queue ci_queue;
 };
 
 #define CPUF_BSP	0x0001		/* CPU is the original BSP */