[src/trunk]: src/sys/arch/x86/x86 lapic_delay() disable preemption since the ...

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

details:   https://anonhg.NetBSD.org/src/rev/217334a4c30d
branches:  trunk
changeset: 1010245:217334a4c30d
user:      ad <ad%NetBSD.org@localhost>
date:      Tue May 19 21:39:11 2020 +0000

description:
lapic_delay() disable preemption since the state is very CPU dependent.

diffstat:

 sys/arch/x86/x86/lapic.c |  18 ++++++++++++------
 1 files changed, 12 insertions(+), 6 deletions(-)

diffs (59 lines):

diff -r 4243539ef240 -r 217334a4c30d sys/arch/x86/x86/lapic.c
--- a/sys/arch/x86/x86/lapic.c  Tue May 19 21:14:20 2020 +0000
+++ b/sys/arch/x86/x86/lapic.c  Tue May 19 21:39:11 2020 +0000
@@ -1,7 +1,7 @@
-/*     $NetBSD: lapic.c,v 1.78 2020/05/02 16:44:36 bouyer Exp $        */
+/*     $NetBSD: lapic.c,v 1.79 2020/05/19 21:39:11 ad Exp $    */
 
 /*-
- * Copyright (c) 2000, 2008 The NetBSD Foundation, Inc.
+ * Copyright (c) 2000, 2008, 2020 The NetBSD Foundation, Inc.
  * All rights reserved.
  *
  * This code is derived from software contributed to The NetBSD Foundation
@@ -32,7 +32,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: lapic.c,v 1.78 2020/05/02 16:44:36 bouyer Exp $");
+__KERNEL_RCSID(0, "$NetBSD: lapic.c,v 1.79 2020/05/19 21:39:11 ad Exp $");
 
 #include "acpica.h"
 #include "ioapic.h"
@@ -727,12 +727,17 @@
 lapic_delay(unsigned int usec)
 {
        int32_t xtick, otick;
-       int64_t deltat;         /* XXX may want to be 64bit */
+       int64_t deltat;
 
+       /* XXX Bad to disable preemption, but it's tied to the cpu. */
+       kpreempt_disable();
        otick = lapic_gettick();
 
-       if (usec <= 0)
+       if (usec <= 0) {
+               kpreempt_enable();
                return;
+       }
+
        if (usec <= 25)
                deltat = lapic_delaytab[usec];
        else
@@ -741,7 +746,7 @@
        while (deltat > 0) {
                xtick = lapic_gettick();
                if (lapic_broken_periodic && xtick == 0 && otick == 0) {
-                       lapic_initclocks();
+                       lapic_reset();
                        xtick = lapic_gettick();
                        if (xtick == 0)
                                panic("lapic timer stopped ticking");
@@ -754,6 +759,7 @@
 
                x86_pause();
        }
+       kpreempt_enable();
 }
 
 /*