KVM: x86: hyperv: implement PV IPI send hypercalls

Using hypercall for sending IPIs is faster because this allows to specify
any number of vCPUs (even > 64 with sparse CPU set), the whole procedure
will take only one VMEXIT.

Current Hyper-V TLFS (v5.0b) claims that HvCallSendSyntheticClusterIpi
hypercall can't be 'fast' (passing parameters through registers) but
apparently this is not true, Windows always uses it as 'fast' so we need
to support that.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Vitaly Kuznetsov
2018-09-26 19:02:59 +02:00
committed by Paolo Bonzini
parent 2cefc5feb8
commit 214ff83d44
5 changed files with 166 additions and 0 deletions

View File

@@ -4791,3 +4791,10 @@ CPU when the exception is taken. If this virtual SError is taken to EL1 using
AArch64, this value will be reported in the ISS field of ESR_ELx.
See KVM_CAP_VCPU_EVENTS for more details.
8.20 KVM_CAP_HYPERV_SEND_IPI
Architectures: x86
This capability indicates that KVM supports paravirtualized Hyper-V IPI send
hypercalls:
HvCallSendSyntheticClusterIpi, HvCallSendSyntheticClusterIpiEx.