Re: [PATCH 2/2] i386: Use the right wrapper to disable the NMI watchdog

From: Björn Steinbrink
Date: Fri Jun 08 2007 - 14:50:28 EST


When disabled through /proc/sys/kernel/nmi_watchdog, the NMI watchdog
uses the stop() method directly, which does not decrement the activity
counter, leading to a BUG(). Use the wrapper function instead to fix
that.

Signed-off-by: Björn Steinbrink <B.Steinbrink@xxxxxx>
---
diff --git a/arch/i386/kernel/cpu/perfctr-watchdog.c b/arch/i386/kernel/cpu/perfctr-watchdog.c
index 2b04c8f..f0b6763 100644
--- a/arch/i386/kernel/cpu/perfctr-watchdog.c
+++ b/arch/i386/kernel/cpu/perfctr-watchdog.c
@@ -28,7 +28,7 @@ struct wd_ops {
void (*unreserve)(void);
int (*setup)(unsigned nmi_hz);
void (*rearm)(struct nmi_watchdog_ctlblk *wd, unsigned nmi_hz);
- void (*stop)(void *);
+ void (*stop)(void);
unsigned perfctr;
unsigned evntsel;
u64 checkbit;
@@ -142,7 +142,7 @@ void disable_lapic_nmi_watchdog(void)
if (atomic_read(&nmi_active) <= 0)
return;

- on_each_cpu(wd_ops->stop, NULL, 0, 1);
+ on_each_cpu(stop_apic_nmi_watchdog, NULL, 0, 1);
wd_ops->unreserve();

BUG_ON(atomic_read(&nmi_active) != 0);
@@ -255,7 +255,7 @@ static int setup_k7_watchdog(unsigned nmi_hz)
return 1;
}

-static void single_msr_stop_watchdog(void *arg)
+static void single_msr_stop_watchdog(void)
{
struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);

@@ -442,7 +442,7 @@ static int setup_p4_watchdog(unsigned nmi_hz)
return 1;
}

-static void stop_p4_watchdog(void *arg)
+static void stop_p4_watchdog(void)
{
struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk);
wrmsr(wd->cccr_msr, 0, 0);
@@ -628,7 +634,7 @@ int lapic_watchdog_init(unsigned nmi_hz)
void lapic_watchdog_stop(void)
{
if (wd_ops)
- wd_ops->stop(NULL);
+ wd_ops->stop();
}

unsigned lapic_adjust_nmi_hz(unsigned hz)
-
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