[RFC PATCH 1/2] KVM: selftests: Add a macro to get string of vm_mem_backing_src_type

[Yanan Wang]

Add a macro to get string of the backing source memory type, so that
application can add choices for source types in the help() function,
and users can specify which type to use for testing.

Signed-off-by: Yanan Wang <wangyanan55@xxxxxxxxxx>
---
 tools/testing/selftests/kvm/include/kvm_util.h | 3 +++
 tools/testing/selftests/kvm/lib/kvm_util.c     | 8 ++++++++
 2 files changed, 11 insertions(+)

diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 5cbb861525ed..f5fc29dc9ee6 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -69,7 +69,9 @@ enum vm_guest_mode {
 #define PTES_PER_MIN_PAGE	ptes_per_page(MIN_PAGE_SIZE)
 
 #define vm_guest_mode_string(m) vm_guest_mode_string[m]
+#define vm_mem_backing_src_type_string(s) vm_mem_backing_src_type_string[s]
 extern const char * const vm_guest_mode_string[];
+extern const char * const vm_mem_backing_src_type_string[];
 
 struct vm_guest_mode_params {
 	unsigned int pa_bits;
@@ -83,6 +85,7 @@ enum vm_mem_backing_src_type {
 	VM_MEM_SRC_ANONYMOUS,
 	VM_MEM_SRC_ANONYMOUS_THP,
 	VM_MEM_SRC_ANONYMOUS_HUGETLB,
+	NUM_VM_BACKING_SRC_TYPES,
 };
 
 int kvm_check_cap(long cap);
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index fa5a90e6c6f0..a9b651c7f866 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -165,6 +165,14 @@ const struct vm_guest_mode_params vm_guest_mode_params[] = {
 _Static_assert(sizeof(vm_guest_mode_params)/sizeof(struct vm_guest_mode_params) == NUM_VM_MODES,
 	       "Missing new mode params?");
 
+const char * const vm_mem_backing_src_type_string[] = {
+	"VM_MEM_SRC_ANONYMOUS        ",
+	"VM_MEM_SRC_ANONYMOUS_THP    ",
+	"VM_MEM_SRC_ANONYMOUS_HUGETLB",
+};
+_Static_assert(sizeof(vm_mem_backing_src_type_string)/sizeof(char *) == NUM_VM_BACKING_SRC_TYPES,
+	       "Missing new source type strings?");
+
 /*
  * VM Create
  *
-- 
2.23.0