> atomic_set(&kvm->online_vcpus, 0);
> mutex_unlock(&kvm->lock);
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index c8df733eed41..eb9fb5b493ac 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -386,12 +386,17 @@ struct kvm_memslots {
> int used_slots;
> };
>
> +struct kvm_vcpus {
> + u32 online;
> + struct kvm_vcpu *array[];
On option could be to simply chunk it:
+struct kvm_vcpus {
+ struct kvm_vcpu vcpus[32];
+};
+
/*
* Note:
* memslots are not sorted by id anymore, please use id_to_memslot()
@@ -391,7 +395,7 @@ struct kvm {
struct mutex slots_lock;
struct mm_struct *mm; /* userspace tied to this vm */
struct kvm_memslots __rcu *memslots[KVM_ADDRESS_SPACE_NUM];
- struct kvm_vcpu *vcpus[KVM_MAX_VCPUS];
+ struct kvm_vcpus vcpus[(KVM_MAX_VCPUS + 31) / 32];
/*
* created_vcpus is protected by kvm->lock, and is incremented
@@ -483,12 +487,14 @@ static inline struct kvm_io_bus
*kvm_get_bus(struct kvm *kvm, enum kvm_bus idx)
1. make nobody access kvm->vcpus directly (factor out)
2. allocate next chunk if necessary when creating a VCPU and store
pointer using WRITE_ONCE
3. use READ_ONCE to test for availability of the current chunk
kvm_for_each_vcpu just has to use READ_ONCE to access/test for the right
chunk. Pointers never get invalid. No RCU needed. Sleeping in the loop
is possible.
--
Thanks,
David
