[PATCH RFC v3 3/9] KVM: remember position in kvm->vcpus array
From: cohuck@redhat.com (Cornelia Huck)
Date: 2017-08-29 11:31:10
Also in:
kvm, linux-mips, linux-s390, lkml
On Mon, 21 Aug 2017 22:35:24 +0200 Radim Kr?m?? [off-list ref] wrote:
quoted hunk ↗ jump to hunk
Signed-off-by: Radim Kr?m?? <redacted> --- include/linux/kvm_host.h | 11 +++-------- virt/kvm/kvm_main.c | 5 ++++- 2 files changed, 7 insertions(+), 9 deletions(-)diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 6882538eda32..a8ff956616d2 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h@@ -220,7 +220,8 @@ struct kvm_vcpu { struct preempt_notifier preempt_notifier; #endif int cpu; - int vcpu_id; + int vcpu_id; /* id given by userspace at creation */ + int vcpus_idx; /* index in kvm->vcpus array */
I predict confusion in the future over which is which... maybe s/vcpus_idx/vcpus_array_pos/ or something like that?
quoted hunk ↗ jump to hunk
int srcu_idx; int mode; unsigned long requests;@@ -516,13 +517,7 @@ static inline struct kvm_vcpu *kvm_get_vcpu_by_id(struct kvm *kvm, int id) static inline int kvm_vcpu_get_idx(struct kvm_vcpu *vcpu) { - struct kvm_vcpu *tmp; - int idx; - - kvm_for_each_vcpu(idx, tmp, vcpu->kvm) - if (tmp == vcpu) - return idx; - BUG(); + return vcpu->vcpus_idx; } #define kvm_for_each_memslot(memslot, slots) \diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index e17c40d986f3..caf8323f7df7 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c@@ -2498,7 +2498,10 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id) goto unlock_vcpu_destroy; } - BUG_ON(kvm->vcpus[atomic_read(&kvm->online_vcpus)]); + vcpu->vcpus_idx = atomic_read(&kvm->online_vcpus); + + BUG_ON(kvm->vcpus[vcpu->vcpus_idx]); + /* Now it's all set up, let userspace reach it */ kvm_get_kvm(kvm);
I like the concept.