Re: [PATCH v2] kunit: Print test statistics on failure

On Tue, Aug 3, 2021 at 10:08 PM David Gow davidgow@google.com wrote:

When a number of tests fail, it can be useful to get higher-level statistics of how many tests are failing (or how many parameters are failing in parameterised tests), and in what cases or suites. This is already done by some non-KUnit tests, so add support for automatically generating these for KUnit tests.

This change adds a 'kunit.stats_enabled' switch which has three values:

• 0: No stats are printed (current behaviour)
• 1: Stats are printed only for tests/suites with more than one subtest (new default)
• 2: Always print test statistics

For parameterised tests, the summary line looks as follows: " # inode_test_xtimestamp_decoding: pass:16 fail:0 skip:0 total:16" For test suites, there are two lines looking like this: "# ext4_inode_test: pass:1 fail:0 skip:0 total:1" "# Totals: pass:16 fail:0 skip:0 total:16"

To clarify, this doesn't show up in `kunit.py run` unless you pass --raw_output. So this is more aimed at people running tests via modules.

In that case, it seems more acceptable to have a global knob (kunit.stats_enabled) for turning this on, and also that the default is changing.

The first line gives the number of direct subtests, the second "Totals" line is the accumulated sum of all tests and test parameters.

This format is based on the one used by kselftest[1].

Signed-off-by: David Gow davidgow@google.com

This is the long-awaited v2 of the test statistics patch: https://lore.kernel.org/linux-kselftest/20201211072319.533803-1-davidgow@goo...

It updates the patch to apply on current mainline kernels, takes skipped tests into account, changes the output format to better match what kselftest uses, and addresses some of the comments from v1.

Please let me know what you think, in particular:

• Is this sufficient to assuage any worries about porting tests to KUnit?
• Are we printing too many stats by default: for a lot of existing tests many of them are useless. I'm particuarly curious about the separate "Totals" line, versus the per-suite line -- is that useful? Should it only be printed when the totals differ?
• Is the output format sufficiently legible for people and/or tools which may want to parse it?

Cheers, -- David

Changelog:

Changes since v1: https://lore.kernel.org/linux-kselftest/20201211072319.533803-1-davidgow@goo...

• Rework to use a new struct kunit_result_stats, with helper functions for adding results, accumulating them over nested structures, etc.
• Support skipped tests, report them separately from failures and passes.
• New output format to better match kselftest:
  • "pass:n fail:n skip:n total:n"
• Changes to stats_enabled parameter:
  • Now a module parameter, with description
  • Default "1" option now prints even when no tests fail.
• Improved parser fix which doesn't break crashed test detection.

---

lib/kunit/test.c | 109 ++++++++++++++++++++++++++++ tools/testing/kunit/kunit_parser.py | 2 +- 2 files changed, 110 insertions(+), 1 deletion(-)

diff --git a/lib/kunit/test.c b/lib/kunit/test.c index d79ecb86ea57..f246b847024e 100644 --- a/lib/kunit/test.c +++ b/lib/kunit/test.c @@ -10,6 +10,7 @@ #include <kunit/test-bug.h> #include <linux/kernel.h> #include <linux/kref.h> +#include <linux/moduleparam.h> #include <linux/sched/debug.h> #include <linux/sched.h>

@@ -51,6 +52,51 @@ void __kunit_fail_current_test(const char *file, int line, const char *fmt, ...) EXPORT_SYMBOL_GPL(__kunit_fail_current_test); #endif

+/*

• • KUnit statistic mode:
• • 0 - disabled
• • 1 - only when there is more than one subtest
• • 2 - enabled
• */

+static int kunit_stats_enabled = 1; +module_param_named(stats_enabled, kunit_stats_enabled, int, 0644); +MODULE_PARM_DESC(stats_enabled,

•             "Print test stats: never (0), only for multiple subtests (1), or always (2)");
  

+struct kunit_result_stats {

•   unsigned long passed;
  

•   unsigned long skipped;
  

•   unsigned long failed;
  

•   unsigned long total;
  

+};

+static bool kunit_should_print_stats(struct kunit_result_stats stats) +{

•   if (kunit_stats_enabled == 0)
  

•           return false;
  

•   if (kunit_stats_enabled == 2)
  

•           return true;
  

•   return (stats.total > 1);
  

+}

+static void kunit_print_test_stats(struct kunit *test,

•                              struct kunit_result_stats stats)
  

+{

•   if (!kunit_should_print_stats(stats))
  

•           return;
  

•   kunit_log(KERN_INFO, test,
  

•             KUNIT_SUBTEST_INDENT
  

•             "# %s: pass:%lu fail:%lu skip:%lu total:%lu",
  

•             test->name,
  

•             stats.passed,
  

•             stats.failed,
  

•             stats.skipped,
  

•             stats.total);
  

+}

/*

• Append formatted message to log, size of which is limited to
• KUNIT_LOG_SIZE bytes (including null terminating byte).

@@ -393,15 +439,69 @@ static void kunit_run_case_catch_errors(struct kunit_suite *suite, test_case->status = KUNIT_SUCCESS; }

+static void kunit_print_suite_stats(struct kunit_suite *suite,

•                               struct kunit_result_stats suite_stats,
  

•                               struct kunit_result_stats param_stats)
  

+{

•   if (kunit_should_print_stats(suite_stats)) {
  

•           kunit_log(KERN_INFO, suite,
  

•                     "# %s: pass:%lu fail:%lu skip:%lu total:%lu",
  

•                     suite->name,
  

•                     suite_stats.passed,
  

•                     suite_stats.failed,
  

•                     suite_stats.skipped,
  

•                     suite_stats.total);
  

•   }
  

•   if (kunit_should_print_stats(param_stats)) {
  

•           kunit_log(KERN_INFO, suite,
  

•                     "# Totals: pass:%lu fail:%lu skip:%lu total:%lu",
  

•                     param_stats.passed,
  

•                     param_stats.failed,
  

•                     param_stats.skipped,
  

•                     param_stats.total);
  

•   }
  

+}

+static void kunit_update_stats(struct kunit_result_stats *stats,

•                          enum kunit_status status)
  

+{

•   switch (status) {
  

•   case KUNIT_SUCCESS:
  

•           stats->passed++;
  

•           break;
  

•   case KUNIT_SKIPPED:
  

•           stats->skipped++;
  

•           break;
  

•   case KUNIT_FAILURE:
  

•           stats->failed++;
  

•           break;
  

•   }
  

•   stats->total++;
  

+}

+static void kunit_accumulate_stats(struct kunit_result_stats *total,

•                              struct kunit_result_stats add)
  

+{

•   total->passed += add.passed;
  

•   total->skipped += add.skipped;
  

•   total->failed += add.failed;
  

•   total->total += add.total;
  

+}

int kunit_run_tests(struct kunit_suite *suite) { char param_desc[KUNIT_PARAM_DESC_SIZE]; struct kunit_case *test_case;

•   struct kunit_result_stats suite_stats = { 0 };
  

•   struct kunit_result_stats total_stats = { 0 };
  
    kunit_print_subtest_start(suite);
  
    kunit_suite_for_each_test_case(suite, test_case) {
            struct kunit test = { .param_value = NULL, .param_index = 0 };
  

•           struct kunit_result_stats param_stats = { 0 };
            test_case->status = KUNIT_SKIPPED;
  
            if (test_case->generate_params) {
  

@@ -431,14 +531,23 @@ int kunit_run_tests(struct kunit_suite *suite) test.param_value = test_case->generate_params(test.param_value, param_desc); test.param_index++; }

•                   kunit_update_stats(&param_stats, test.status);
  

•           } while (test.param_value);
  
  

•           kunit_print_test_stats(&test, param_stats);
  

•           kunit_print_ok_not_ok(&test, true, test_case->status,
                                  kunit_test_case_num(suite, test_case),
                                  test_case->name,
                                  test.status_comment);
  

•           kunit_update_stats(&suite_stats, test_case->status);
  

•           kunit_accumulate_stats(&total_stats, param_stats);
    }
  
  

•   kunit_print_suite_stats(suite, suite_stats, total_stats);
    kunit_print_subtest_end(suite);
  
    return 0;
  

diff --git a/tools/testing/kunit/kunit_parser.py b/tools/testing/kunit/kunit_parser.py index b88db3f51dc5..c699f778da06 100644 --- a/tools/testing/kunit/kunit_parser.py +++ b/tools/testing/kunit/kunit_parser.py @@ -137,7 +137,7 @@ def print_log(log) -> None: for m in log: print_with_timestamp(m)

-TAP_ENTRIES = re.compile(r'^(TAP|[\s]*ok|[\s]*not ok|[\s]*[0-9]+..[0-9]+|[\s]*#).*$') +TAP_ENTRIES = re.compile(r'^(TAP|[\s]*ok|[\s]*not ok|[\s]*[0-9]+..[0-9]+|[\s]*# (Subtest:|.*: kunit test case crashed!)).*$')

def consume_non_diagnostic(lines: LineStream) -> None: while lines and not TAP_ENTRIES.match(lines.peek()): -- 2.32.0.554.ge1b32706d8-goog