On 12/05/2011 10:19 PM, 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.
>
> +bool kvm_check_and_clear_guest_paused(int cpu)
> +{
> + 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 = &per_cpu(hv_clock, cpu);
__get_cpu_var(); drop the cpu argument
> + if ((src->flags & PVCLOCK_GUEST_STOPPED) != 0) {
> + src->flags = src->flags & (~PVCLOCK_GUEST_STOPPED);
Isn't this racy? Between reading and writing src->flags, we can exit to
the hypervisor and add/remove new flags. The write then overrides those
new flags.
> + ret = true;
> + }
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(kvm_check_and_clear_guest_paused);
> +
> static struct clocksource kvm_clock = {
> .name = "kvm-clock",
> .read = kvm_clock_get_cycles,
--
error compiling committee.c: too many arguments to function
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