Commit 8df6a61c authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: Update halt-polling stats if and only if halt-polling was attempted 



Don't update halt-polling stats if halt-polling wasn't attempted.  This is
a nop as @poll_ns is guaranteed to be '0' (poll_end == start); in a future
patch (to move the histogram stats into the helper), it will avoid to
avoid a discrepancy in what is considered a "successful" halt-poll.

No functional change intended.

Reviewed-by: default avatarDavid Matlack <dmatlack@google.com>
Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Message-Id: <20211009021236.4122790-6-seanjc@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 510958e9

virt/kvm/kvm_main.c

+5 −3
Original line number Diff line number Diff line
@@ -3288,6 +3288,7 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu) 
{

	struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);

	bool halt_poll_allowed = !kvm_arch_no_poll(vcpu);

	bool do_halt_poll = halt_poll_allowed && vcpu->halt_poll_ns;

	ktime_t start, cur, poll_end;

	bool waited = false;

	u64 block_ns;
@@ -3295,7 +3296,7 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu) 
	kvm_arch_vcpu_blocking(vcpu);



	start = cur = poll_end = ktime_get();

	if (vcpu->halt_poll_ns && halt_poll_allowed) {

	if (do_halt_poll) {

		ktime_t stop = ktime_add_ns(ktime_get(), vcpu->halt_poll_ns);



		++vcpu->stat.generic.halt_attempted_poll;
@@ -3347,6 +3348,7 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu) 
	kvm_arch_vcpu_unblocking(vcpu);

	block_ns = ktime_to_ns(cur) - ktime_to_ns(start);



	if (do_halt_poll)

		update_halt_poll_stats(

			vcpu, ktime_to_ns(ktime_sub(poll_end, start)), waited);