Commit a72faf25 authored by Xiao Guangrong's avatar Xiao Guangrong Committed by Avi Kivity
Browse files

KVM: MMU: trace fast page fault 



To see what happen on this path and help us to optimize it

Signed-off-by: default avatarXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent c7ba5b48

arch/x86/kvm/mmu.c

+2 −0
Original line number Diff line number Diff line
@@ -2776,6 +2776,8 @@ static bool fast_page_fault(struct kvm_vcpu *vcpu, gva_t gva, int level, 
	 */

	ret = fast_pf_fix_direct_spte(vcpu, iterator.sptep, spte);

exit:

	trace_fast_page_fault(vcpu, gva, error_code, iterator.sptep,

			      spte, ret);

	walk_shadow_page_lockless_end(vcpu);



	return ret;

arch/x86/kvm/mmutrace.h

+38 −0
Original line number Diff line number Diff line
@@ -243,6 +243,44 @@ TRACE_EVENT( 
	TP_printk("addr:%llx gfn %llx access %x", __entry->addr, __entry->gfn,

		  __entry->access)

);



#define __spte_satisfied(__spte)				\

	(__entry->retry && is_writable_pte(__entry->__spte))



TRACE_EVENT(

	fast_page_fault,

	TP_PROTO(struct kvm_vcpu *vcpu, gva_t gva, u32 error_code,

		 u64 *sptep, u64 old_spte, bool retry),

	TP_ARGS(vcpu, gva, error_code, sptep, old_spte, retry),



	TP_STRUCT__entry(

		__field(int, vcpu_id)

		__field(gva_t, gva)

		__field(u32, error_code)

		__field(u64 *, sptep)

		__field(u64, old_spte)

		__field(u64, new_spte)

		__field(bool, retry)

	),



	TP_fast_assign(

		__entry->vcpu_id = vcpu->vcpu_id;

		__entry->gva = gva;

		__entry->error_code = error_code;

		__entry->sptep = sptep;

		__entry->old_spte = old_spte;

		__entry->new_spte = *sptep;

		__entry->retry = retry;

	),



	TP_printk("vcpu %d gva %lx error_code %s sptep %p old %#llx"

		  " new %llx spurious %d fixed %d", __entry->vcpu_id,

		  __entry->gva, __print_flags(__entry->error_code, "|",

		  kvm_mmu_trace_pferr_flags), __entry->sptep,

		  __entry->old_spte, __entry->new_spte,

		  __spte_satisfied(old_spte), __spte_satisfied(new_spte)

	)

);

#endif /* _TRACE_KVMMMU_H */



#undef TRACE_INCLUDE_PATH