[PATCH 12/13] KVM: MMU: trace fast page fault

Xiao Guangrong
2012-03-29T09:27:45Z

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

Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
---
arch/x86/kvm/mmu.c | 2 ++
arch/x86/kvm/mmutrace.h | 43 +++++++++++++++++++++++++++++++++++++++++++
2 files changed, 45 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index 4a01be4..94cd31d 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -3011,6 +3011,8 @@ fast_page_fault(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn, int level,
expected_access, fn);

exit:
+ trace_fast_page_fault(vcpu, gva, gfn, error_code, iterator.sptep,
+ spte, ret);
walk_shadow_page_lockless_end(vcpu);

return ret;
diff --git a/arch/x86/kvm/mmutrace.h b/arch/x86/kvm/mmutrace.h
index 89fb0e8..a81c8a7 100644
--- a/arch/x86/kvm/mmutrace.h
+++ b/arch/x86/kvm/mmutrace.h
@@ -243,6 +243,49 @@ TRACE_EVENT(
TP_printk("addr:%llx gfn %llx access %x", __entry->addr, __entry->gfn,
__entry->access)
);
+
+static u32 page_fault_expected_access(u32 error_code);
+static bool spte_satisfied(u64 spte, u32 access);
+#define __spte_satisfied(__spte) \
+ (__entry->success && spte_satisfied(__entry->__spte, \
+ page_fault_expected_access(__entry->error_code)))
+TRACE_EVENT(
+ fast_page_fault,
+ TP_PROTO(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn, u32 error_code,
+ u64 *sptep, u64 old_spte, bool retry),
+ TP_ARGS(vcpu, gva, gfn, error_code, sptep, old_spte, retry),
+
+ TP_STRUCT__entry(
+ __field(int, vcpu_id)
+ __field(gva_t, gva)
+ __field(gfn_t, gfn)
+ __field(u32, error_code)
+ __field(u64 *, sptep)
+ __field(u64, old_spte)
+ __field(u64, new_spte)
+ __field(bool, success)
+ ),
+
+ TP_fast_assign(
+ __entry->vcpu_id = vcpu->vcpu_id;
+ __entry->gva = gva;
+ __entry->gfn = gfn;
+ __entry->error_code = error_code;
+ __entry->sptep = sptep;
+ __entry->old_spte = old_spte;
+ __entry->new_spte = *sptep;
+ __entry->success = retry;
+ ),
+
+ TP_printk("vcpu %d gva %lx gfn %llx error_code %s sptep %p "
+ "old %#llx new %llx spurious %d fixed %d", __entry->vcpu_id,
+ __entry->gva, __entry->gfn,
+ __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
--
1.7.7.6