[PATCH 2/4] selftest/mm: Add helper for logging test start and results

[Mark Brown <broonie@kernel.org>]

Several of the MM tests have a pattern of printing a description of the
test to be run then reporting the actual TAP result using a generic string
not connected to the specific test, often in a shared function used by many
tests. The name reported typically varies depending on the specific result
rather than the test too. This causes problems for tooling that works with
test results, the names reported with the results are used to deduplicate
tests and track them between runs so both duplicated names and changing
names cause trouble for things like UIs and automated bisection.

As a first step towards matching these tests better with the expectations
of kselftest provide helpers which record the test name as part of the
initial print and then use that as part of reporting a result.

This is not added as a generic kselftest helper partly because the use of
a variable to store the test name doesn't fit well with the header only
implementation of kselftest.h and partly because it's not really an
intended pattern. Ideally at some point the mm tests that use it will be
updated to not need it.

Signed-off-by: Mark Brown <broonie@kernel.org>
---
 tools/testing/selftests/mm/vm_util.h | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
index 6effafdc4d8a..4944e4c79051 100644
--- a/tools/testing/selftests/mm/vm_util.h
+++ b/tools/testing/selftests/mm/vm_util.h
@@ -3,6 +3,7 @@
 #include <stdbool.h>
 #include <sys/mman.h>
 #include <err.h>
+#include <stdarg.h>
 #include <strings.h> /* ffsl() */
 #include <unistd.h> /* _SC_PAGESIZE */
 #include "../kselftest.h"
@@ -74,6 +75,25 @@ int uffd_register_with_ioctls(int uffd, void *addr, uint64_t len,
 unsigned long get_free_hugepages(void);
 bool check_vmflag_io(void *addr);
 
+/* These helpers need to be inline to match the kselftest.h idiom. */
+static char test_name[1024];
+
+static inline void log_test_start(const char *name, ...)
+{
+	va_list args;
+	va_start(args, name);
+
+	vsnprintf(test_name, sizeof(test_name), name, args);
+	ksft_print_msg("[RUN] %s\n", test_name);
+
+	va_end(args);
+}
+
+static inline void log_test_result(int result)
+{
+	ksft_test_result_report(result, "%s\n", test_name);
+}
+
 /*
  * On ppc64 this will only work with radix 2M hugepage size
  */

-- 
2.39.5