KVM: x86: hyperv: optimize 'all cpus' case in kvm_hv_flush_tlb()

We can use 'NULL' to represent 'all cpus' case in
kvm_make_vcpus_request_mask() and avoid building vCPU mask with
all vCPUs.

Suggested-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Vitaly Kuznetsov
2018-08-22 12:18:29 +02:00
committed by Paolo Bonzini
parent 9170200ec0
commit a812297c4f
2 changed files with 25 additions and 23 deletions

View File

@@ -1325,35 +1325,39 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *current_vcpu, u64 ingpa,
cpumask_clear(&hv_current->tlb_lush);
if (all_cpus) {
kvm_make_vcpus_request_mask(kvm,
KVM_REQ_TLB_FLUSH | KVM_REQUEST_NO_WAKEUP,
NULL, &hv_current->tlb_lush);
goto ret_success;
}
kvm_for_each_vcpu(i, vcpu, kvm) {
struct kvm_vcpu_hv *hv = &vcpu->arch.hyperv;
int bank = hv->vp_index / 64, sbank = 0;
if (!all_cpus) {
/* Banks >64 can't be represented */
if (bank >= 64)
continue;
/* Banks >64 can't be represented */
if (bank >= 64)
continue;
/* Non-ex hypercalls can only address first 64 vCPUs */
if (!ex && bank)
continue;
/* Non-ex hypercalls can only address first 64 vCPUs */
if (!ex && bank)
continue;
if (ex) {
/*
* Check is the bank of this vCPU is in sparse
* set and get the sparse bank number.
*/
sbank = get_sparse_bank_no(valid_bank_mask,
bank);
if (ex) {
/*
* Check is the bank of this vCPU is in sparse
* set and get the sparse bank number.
*/
sbank = get_sparse_bank_no(valid_bank_mask, bank);
if (sbank < 0)
continue;
}
if (!(sparse_banks[sbank] & BIT_ULL(hv->vp_index % 64)))
if (sbank < 0)
continue;
}
if (!(sparse_banks[sbank] & BIT_ULL(hv->vp_index % 64)))
continue;
/*
* vcpu->arch.cr3 may not be up-to-date for running vCPUs so we
* can't analyze it here, flush TLB regardless of the specified