From 0b6a39f7ebcb1c82587ce35b401c513eed41ac5c Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Mon, 9 Jun 2008 13:29:43 +0200
Subject: [PATCH] Revert "x86: fix ioapic bug again"
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This reverts commit 6e908947b4995bc0e551a8257c586d5c3e428201.
Németh Márton reported:
| there is a problem in 2.6.26-rc3 which was not there in case of
| 2.6.25: the CPU wakes up ~90,000 times per sec instead of ~60 per sec.
|
| I also "git bisected" the problem, the result is:
|
| 6e908947b4995bc0e551a8257c586d5c3e428201 is first bad commit
| commit 6e908947b4995bc0e551a8257c586d5c3e428201
| Author: Ingo Molnar <mingo@elte.hu>
| Date: Fri Mar 21 14:32:36 2008 +0100
|
| x86: fix ioapic bug again
the original problem is fixed by Maciej W. Rozycki in the tip/x86/apic
branch (confirmed by Márton), but those changes are too intrusive for
v2.6.26 so we'll go for the less intrusive (repeated) revert now.
Reported-and-bisected-by: Németh Márton <nm127@freemail.hu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
arch/x86/kernel/io_apic_32.c | 12 ++----------
arch/x86/kernel/nmi_32.c | 9 ++-------
2 files changed, 4 insertions(+), 17 deletions(-)
diff --git a/arch/x86/kernel/io_apic_32.c b/arch/x86/kernel/io_apic_32.c
index a40d54fc1fdd8..4dc8600d9d207 100644
--- a/arch/x86/kernel/io_apic_32.c
+++ b/arch/x86/kernel/io_apic_32.c
@@ -2130,14 +2130,10 @@ static inline void __init check_timer(void)
{
int apic1, pin1, apic2, pin2;
int vector;
- unsigned int ver;
unsigned long flags;
local_irq_save(flags);
- ver = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(ver);
-
/*
* get/set the timer IRQ vector:
*/
@@ -2150,15 +2146,11 @@ static inline void __init check_timer(void)
* mode for the 8259A whenever interrupts are routed
* through I/O APICs. Also IRQ0 has to be enabled in
* the 8259A which implies the virtual wire has to be
- * disabled in the local APIC. Finally timer interrupts
- * need to be acknowledged manually in the 8259A for
- * timer_interrupt() and for the i82489DX when using
- * the NMI watchdog.
+ * disabled in the local APIC.
*/
apic_write_around(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);
init_8259A(1);
- timer_ack = !cpu_has_tsc;
- timer_ack |= (nmi_watchdog == NMI_IO_APIC && !APIC_INTEGRATED(ver));
+ timer_ack = 1;
if (timer_over_8254 > 0)
enable_8259A_irq(0);
diff --git a/arch/x86/kernel/nmi_32.c b/arch/x86/kernel/nmi_32.c
index 11b14bbaa61e6..84160f74eeb0a 100644
--- a/arch/x86/kernel/nmi_32.c
+++ b/arch/x86/kernel/nmi_32.c
@@ -26,7 +26,6 @@
#include <asm/smp.h>
#include <asm/nmi.h>
-#include <asm/timer.h>
#include "mach_traps.h"
@@ -82,7 +81,7 @@ int __init check_nmi_watchdog(void)
prev_nmi_count = kmalloc(NR_CPUS * sizeof(int), GFP_KERNEL);
if (!prev_nmi_count)
- goto error;
+ return -1;
printk(KERN_INFO "Testing NMI watchdog ... ");
@@ -119,7 +118,7 @@ int __init check_nmi_watchdog(void)
if (!atomic_read(&nmi_active)) {
kfree(prev_nmi_count);
atomic_set(&nmi_active, -1);
- goto error;
+ return -1;
}
printk("OK.\n");
@@ -130,10 +129,6 @@ int __init check_nmi_watchdog(void)
kfree(prev_nmi_count);
return 0;
-error:
- timer_ack = !cpu_has_tsc;
-
- return -1;
}
static int __init setup_nmi_watchdog(char *str)
--
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