On Wed, 14 Mar 2012 11:12:35 +0100, Jan Kiszka wrote:
On 2012-03-10 20:37, Eric B Munson wrote:
When a host stops or suspends a VM it will set a flag to show this.
The
watchdog will use these functions to determine if a softlockup is
real, or the
result of a suspended VM.
...
diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index f8492da..4ba090c 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -22,6 +22,7 @@
#include <asm/msr.h>
#include <asm/apic.h>
#include <linux/percpu.h>
+#include <linux/hardirq.h>
#include <asm/x86_init.h>
#include <asm/reboot.h>
@@ -114,6 +115,26 @@ static void kvm_get_preset_lpj(void)
preset_lpj = lpj;
}
+bool kvm_check_and_clear_guest_paused(void)
+{
+ bool ret = false;
+ struct pvclock_vcpu_time_info *src;
+
+ /*
+ * per_cpu() is safe here because this function is only called
from
+ * timer functions where preemption is already disabled.
+ */
+ WARN_ON(!in_atomic());
+ src = &__get_cpu_var(hv_clock);
+ if ((src->flags & PVCLOCK_GUEST_STOPPED) != 0) {
+ __this_cpu_and(hv_clock.flags, ~PVCLOCK_GUEST_STOPPED);
+ ret = true;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(kvm_check_and_clear_guest_paused);
Which module is going to use this? I failed to find it, but I may
have
missed something.
The actual reason for this reply: this patches causes a compiler
warning
here, likely due to lacking include for EXPORT_SYMBOL_GPL:
CC arch/x86/kernel/kvmclock.o
/data/linux-kvm/arch/x86/kernel/kvmclock.c:136:1: warning: data
definition has no type or storage class
/data/linux-kvm/arch/x86/kernel/kvmclock.c:136:1: warning: type
defaults
to ‘int’ in declaration of ‘EXPORT_SYMBOL_GPL’
/data/linux-kvm/arch/x86/kernel/kvmclock.c:136:1: warning: parameter
names (without types) in function declaration
Jan
There isn't a module that will use it, I was under the (mistaken)
understanding that
the EXPORT was necessary for use in kernel/watchdog.c. Give that it
isn't, I will
post a patch to remove it shortly.
Eric
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