Commit 2cbd7824 authored by Wanpeng Li's avatar Wanpeng Li Committed by Paolo Bonzini
Browse files

KVM: trace kvm_halt_poll_ns grow/shrink 



Tracepoint for dynamic halt_pool_ns, fired on every potential change.

Signed-off-by: default avatarWanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent aca6ff29

include/trace/events/kvm.h

+30 −0
Original line number Diff line number Diff line
@@ -356,6 +356,36 @@ TRACE_EVENT( 
		  __entry->address)

);



TRACE_EVENT(kvm_halt_poll_ns,

	TP_PROTO(bool grow, unsigned int vcpu_id, int new, int old),

	TP_ARGS(grow, vcpu_id, new, old),



	TP_STRUCT__entry(

		__field(bool, grow)

		__field(unsigned int, vcpu_id)

		__field(int, new)

		__field(int, old)

	),



	TP_fast_assign(

		__entry->grow           = grow;

		__entry->vcpu_id        = vcpu_id;

		__entry->new            = new;

		__entry->old            = old;

	),



	TP_printk("vcpu %u: halt_poll_ns %d (%s %d)",

			__entry->vcpu_id,

			__entry->new,

			__entry->grow ? "grow" : "shrink",

			__entry->old)

);



#define trace_kvm_halt_poll_ns_grow(vcpu_id, new, old) \

	trace_kvm_halt_poll_ns(true, vcpu_id, new, old)

#define trace_kvm_halt_poll_ns_shrink(vcpu_id, new, old) \

	trace_kvm_halt_poll_ns(false, vcpu_id, new, old)



#endif



#endif /* _TRACE_KVM_MAIN_H */

virt/kvm/kvm_main.c

+6 −2
Original line number Diff line number Diff line
@@ -1918,8 +1918,9 @@ EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty); 


static void grow_halt_poll_ns(struct kvm_vcpu *vcpu)

{

	int val = vcpu->halt_poll_ns;

	int old, val;



	old = val = vcpu->halt_poll_ns;

	/* 10us base */

	if (val == 0 && halt_poll_ns_grow)

		val = 10000;
@@ -1927,18 +1928,21 @@ static void grow_halt_poll_ns(struct kvm_vcpu *vcpu) 
		val *= halt_poll_ns_grow;



	vcpu->halt_poll_ns = val;

	trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old);

}



static void shrink_halt_poll_ns(struct kvm_vcpu *vcpu)

{

	int val = vcpu->halt_poll_ns;

	int old, val;



	old = val = vcpu->halt_poll_ns;

	if (halt_poll_ns_shrink == 0)

		val = 0;

	else

		val /= halt_poll_ns_shrink;



	vcpu->halt_poll_ns = val;

	trace_kvm_halt_poll_ns_shrink(vcpu->vcpu_id, val, old);

}



static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)