[PATCH v1 3/4] KVM: selftests: convert vm_get_stat to macro

[Manali Shukla <manali.shukla@amd.com>]

Convert vm_get_stat() to macro to detect typos at compile time.

Add a concatenation trickery to trigger compiler error if vm stat
doesn't exist, so that it is not possible to pass a vcpu stat into
vm_get_stat().

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Manali Shukla <manali.shukla@amd.com>
---
 .../testing/selftests/kvm/include/kvm_util.h  | 33 +++++++++++++++----
 .../kvm/include/x86_64/kvm_util_arch.h        | 16 +++++++++
 2 files changed, 42 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 5dd3acf174f8..bd486a2899ca 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -539,16 +539,35 @@ static inline int check_##type##_##stat##_exists(void)	\
 
 #define STAT_EXISTS(type, stat) (check_##type##_##stat##_exists())
 
+#define DEFINE_GENERIC_VM_STAT					\
+	DEFINE_CHECK_STAT(vm, remote_tlb_flush)			\
+	DEFINE_CHECK_STAT(vm, remote_tlb_flush_requests)	\
+
+/*
+ * Define a default empty macro for architectures which do not specify
+ * arch specific vm stats.
+ */
+#ifndef DEFINE_ARCH_VM_STAT
+#define DEFINE_ARCH_VM_STAT
+#endif
+
+DEFINE_GENERIC_VM_STAT
+DEFINE_ARCH_VM_STAT
+
+#undef DEFINE_GENERIC_VM_STAT
+#undef DEFINE_ARCH_VM_STAT
+
 void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data,
 		   size_t max_elements);
 
-static inline uint64_t vm_get_stat(struct kvm_vm *vm, const char *stat_name)
-{
-	uint64_t data;
-
-	__vm_get_stat(vm, stat_name, &data, 1);
-	return data;
-}
+#define vm_get_stat(vm, stat_name)				\
+({								\
+	uint64_t data;						\
+								\
+	STAT_EXISTS(vm, stat_name);				\
+	__vm_get_stat(vm, #stat_name, &data, 1);		\
+	data;							\
+})
 
 #define DEFINE_GENERIC_VCPU_STAT				\
 	DEFINE_CHECK_STAT(vcpu, halt_successfull_poll)		\
diff --git a/tools/testing/selftests/kvm/include/x86_64/kvm_util_arch.h b/tools/testing/selftests/kvm/include/x86_64/kvm_util_arch.h
index 3cdc3c856ed2..6341c786dc9a 100644
--- a/tools/testing/selftests/kvm/include/x86_64/kvm_util_arch.h
+++ b/tools/testing/selftests/kvm/include/x86_64/kvm_util_arch.h
@@ -48,6 +48,22 @@ do {											\
 	}										\
 } while (0)
 
+#define DEFINE_ARCH_VM_STAT					\
+	DEFINE_CHECK_STAT(vm, mmu_shadow_zapped)		\
+	DEFINE_CHECK_STAT(vm, mmu_pte_write)			\
+	DEFINE_CHECK_STAT(vm, mmu_pde_zapped)			\
+	DEFINE_CHECK_STAT(vm, mmu_flooded)			\
+	DEFINE_CHECK_STAT(vm, mmu_recycled)			\
+	DEFINE_CHECK_STAT(vm, mmu_cache_miss)			\
+	DEFINE_CHECK_STAT(vm, mmu_unsync)			\
+	DEFINE_CHECK_STAT(vm, pages_4k)				\
+	DEFINE_CHECK_STAT(vm, pages_2m)				\
+	DEFINE_CHECK_STAT(vm, pages_1g)				\
+	DEFINE_CHECK_STAT(vm, pages)				\
+	DEFINE_CHECK_STAT(vm, nx_lpage_splits)			\
+	DEFINE_CHECK_STAT(vm, max_mmu_page_hash_collisions)	\
+	DEFINE_CHECK_STAT(vm, max_mmu_rmap_size)		\
+
 #define DEFINE_ARCH_VCPU_STAT					\
 	DEFINE_CHECK_STAT(vcpu, pf_taken)			\
 	DEFINE_CHECK_STAT(vcpu, pf_fixed)			\
-- 
2.34.1