add debugfs support for displaying kunit test suite results; this is especially useful for module-loaded tests to allow disentangling of test result display from other dmesg events. debugfs support is provided if CONFIG_KUNIT_DEBUGFS=y.

As well as printk()ing messages, we append them to a per-test log.

Signed-off-by: Alan Maguire alan.maguire@oracle.com Reviewed-by: Brendan Higgins brendanhiggins@google.com Reviewed-by: Frank Rowand frank.rowand@sony.com --- include/kunit/test.h | 54 +++++++++++++++--- lib/kunit/Kconfig | 8 +++ lib/kunit/Makefile | 4 ++ lib/kunit/debugfs.c | 116 ++++++++++++++++++++++++++++++++++++++ lib/kunit/debugfs.h | 30 ++++++++++ lib/kunit/kunit-test.c | 4 +- lib/kunit/test.c | 147 ++++++++++++++++++++++++++++++++++++++----------- 7 files changed, 322 insertions(+), 41 deletions(-) create mode 100644 lib/kunit/debugfs.c create mode 100644 lib/kunit/debugfs.h

diff --git a/include/kunit/test.h b/include/kunit/test.h index 2dfb550..f7b2ed4c 100644 --- a/include/kunit/test.h +++ b/include/kunit/test.h @@ -81,6 +81,9 @@ struct kunit_resource {

struct kunit;

+/* Size of log associated with test. */ +#define KUNIT_LOG_SIZE 512 + /** * struct kunit_case - represents an individual test case. * @@ -123,8 +126,14 @@ struct kunit_case {

/* private: internal use only. */ bool success; + char *log; };

+static inline char *kunit_status_to_string(bool status) +{ + return status ? "ok" : "not ok"; +} + /** * KUNIT_CASE - A helper for creating a &struct kunit_case * @@ -157,6 +166,10 @@ struct kunit_suite { int (*init)(struct kunit *test); void (*exit)(struct kunit *test); struct kunit_case *test_cases; + + /* private - internal use only */ + struct dentry *debugfs; + char *log; };

/** @@ -175,6 +188,7 @@ struct kunit {

/* private: internal use only. */ const char *name; /* Read only after initialization! */ + char *log; /* Points at case log after initialization */ struct kunit_try_catch try_catch; /* * success starts as true, and may only be set to false during a @@ -193,10 +207,19 @@ struct kunit { struct list_head resources; /* Protected by lock. */ };

-void kunit_init_test(struct kunit *test, const char *name); +void kunit_init_test(struct kunit *test, const char *name, char *log);

int kunit_run_tests(struct kunit_suite *suite);

+size_t kunit_suite_num_test_cases(struct kunit_suite *suite); + +unsigned int kunit_test_case_num(struct kunit_suite *suite, + struct kunit_case *test_case); + +int __kunit_test_suites_init(struct kunit_suite **suites); + +void __kunit_test_suites_exit(struct kunit_suite **suites); + /** * kunit_test_suites() - used to register one or more &struct kunit_suite * with KUnit. @@ -226,20 +249,22 @@ struct kunit { static struct kunit_suite *suites[] = { __VA_ARGS__, NULL}; \ static int kunit_test_suites_init(void) \ { \ - unsigned int i; \ - for (i = 0; suites[i] != NULL; i++) \ - kunit_run_tests(suites[i]); \ - return 0; \ + return __kunit_test_suites_init(suites); \ } \ late_initcall(kunit_test_suites_init); \ static void __exit kunit_test_suites_exit(void) \ { \ - return; \ + return __kunit_test_suites_exit(suites); \ } \ module_exit(kunit_test_suites_exit)

#define kunit_test_suite(suite) kunit_test_suites(&suite)

+#define kunit_suite_for_each_test_case(suite, test_case) \ + for (test_case = suite->test_cases; test_case->run_case; test_case++) + +bool kunit_suite_has_succeeded(struct kunit_suite *suite); + /* * Like kunit_alloc_resource() below, but returns the struct kunit_resource * object that contains the allocation. This is mostly for testing purposes. @@ -356,8 +381,21 @@ static inline void *kunit_kzalloc(struct kunit *test, size_t size, gfp_t gfp)

void kunit_cleanup(struct kunit *test);

-#define kunit_printk(lvl, test, fmt, ...) \ - printk(lvl "\t# %s: " fmt, (test)->name, ##__VA_ARGS__) +void kunit_log_append(char *log, const char *fmt, ...); + +/* + * printk and log to per-test or per-suite log buffer. Logging only done + * if CONFIG_KUNIT_DEBUGFS is 'y'; if it is 'n', no log is allocated/used. + */ +#define kunit_log(lvl, test_or_suite, fmt, ...) \ + do { \ + printk(lvl fmt, ##__VA_ARGS__); \ + kunit_log_append((test_or_suite)->log, fmt "\n", \ + ##__VA_ARGS__); \ + } while (0) + +#define kunit_printk(lvl, test, fmt, ...) \ + kunit_log(lvl, test, "\t# %s: " fmt, (test)->name, ##__VA_ARGS__)

/** * kunit_info() - Prints an INFO level message associated with @test. diff --git a/lib/kunit/Kconfig b/lib/kunit/Kconfig index 065aa16..95d12e3 100644 --- a/lib/kunit/Kconfig +++ b/lib/kunit/Kconfig @@ -14,6 +14,14 @@ menuconfig KUNIT

if KUNIT

+config KUNIT_DEBUGFS + bool "KUnit - Enable /sys/kernel/debug/kunit debugfs representation" + help + Enable debugfs representation for kunit. Currently this consists + of /sys/kernel/debug/kunit/<test_suite>/results files for each + test suite, which allow users to see results of the last test suite + run that occurred. + config KUNIT_TEST tristate "KUnit test for KUnit" help diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile index fab5564..724b943 100644 --- a/lib/kunit/Makefile +++ b/lib/kunit/Makefile @@ -5,6 +5,10 @@ kunit-objs += test.o \ assert.o \ try-catch.o

+ifeq ($(CONFIG_KUNIT_DEBUGFS),y) +kunit-objs += debugfs.o +endif + obj-$(CONFIG_KUNIT_TEST) += kunit-test.o

# string-stream-test compiles built-in only. diff --git a/lib/kunit/debugfs.c b/lib/kunit/debugfs.c new file mode 100644 index 0000000..9214c49 --- /dev/null +++ b/lib/kunit/debugfs.c @@ -0,0 +1,116 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2020, Oracle and/or its affiliates. + * Author: Alan Maguire alan.maguire@oracle.com + */ + +#include <linux/debugfs.h> +#include <linux/module.h> + +#include <kunit/test.h> + +#include "string-stream.h" + +#define KUNIT_DEBUGFS_ROOT "kunit" +#define KUNIT_DEBUGFS_RESULTS "results" + +/* + * Create a debugfs representation of test suites: + * + * Path Semantics + * /sys/kernel/debug/kunit/<testsuite>/results Show results of last run for + * testsuite + * + */ + +static struct dentry *debugfs_rootdir; + +void kunit_debugfs_cleanup(void) +{ + debugfs_remove_recursive(debugfs_rootdir); +} + +void kunit_debugfs_init(void) +{ + if (!debugfs_rootdir) + debugfs_rootdir = debugfs_create_dir(KUNIT_DEBUGFS_ROOT, NULL); +} + +static void debugfs_print_result(struct seq_file *seq, + struct kunit_suite *suite, + struct kunit_case *test_case) +{ + if (!test_case || !test_case->log) + return; + + seq_printf(seq, "%s", test_case->log); +} + +/* + * /sys/kernel/debug/kunit/<testsuite>/results shows all results for testsuite. + */ +static int debugfs_print_results(struct seq_file *seq, void *v) +{ + struct kunit_suite *suite = (struct kunit_suite *)seq->private; + bool success = kunit_suite_has_succeeded(suite); + struct kunit_case *test_case; + + if (!suite || !suite->log) + return 0; + + seq_printf(seq, "%s", suite->log); + + kunit_suite_for_each_test_case(suite, test_case) + debugfs_print_result(seq, suite, test_case); + + seq_printf(seq, "%s %d - %s\n", + kunit_status_to_string(success), 1, suite->name); + return 0; +} + +static int debugfs_release(struct inode *inode, struct file *file) +{ + return single_release(inode, file); +} + +static int debugfs_results_open(struct inode *inode, struct file *file) +{ + struct kunit_suite *suite; + + suite = (struct kunit_suite *)inode->i_private; + + return single_open(file, debugfs_print_results, suite); +} + +static const struct file_operations debugfs_results_fops = { + .open = debugfs_results_open, + .read = seq_read, + .llseek = seq_lseek, + .release = debugfs_release, +}; + +void kunit_debugfs_create_suite(struct kunit_suite *suite) +{ + struct kunit_case *test_case; + + /* Allocate logs before creating debugfs representation. */ + suite->log = kzalloc(KUNIT_LOG_SIZE, GFP_KERNEL); + kunit_suite_for_each_test_case(suite, test_case) + test_case->log = kzalloc(KUNIT_LOG_SIZE, GFP_KERNEL); + + suite->debugfs = debugfs_create_dir(suite->name, debugfs_rootdir); + + debugfs_create_file(KUNIT_DEBUGFS_RESULTS, S_IFREG | 0444, + suite->debugfs, + suite, &debugfs_results_fops); +} + +void kunit_debugfs_destroy_suite(struct kunit_suite *suite) +{ + struct kunit_case *test_case; + + debugfs_remove_recursive(suite->debugfs); + kfree(suite->log); + kunit_suite_for_each_test_case(suite, test_case) + kfree(test_case->log); +} diff --git a/lib/kunit/debugfs.h b/lib/kunit/debugfs.h new file mode 100644 index 0000000..dcc7d75 --- /dev/null +++ b/lib/kunit/debugfs.h @@ -0,0 +1,30 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020, Oracle and/or its affiliates. + */ + +#ifndef _KUNIT_DEBUGFS_H +#define _KUNIT_DEBUGFS_H + +#include <kunit/test.h> + +#ifdef CONFIG_KUNIT_DEBUGFS + +void kunit_debugfs_create_suite(struct kunit_suite *suite); +void kunit_debugfs_destroy_suite(struct kunit_suite *suite); +void kunit_debugfs_init(void); +void kunit_debugfs_cleanup(void); + +#else + +static inline void kunit_debugfs_create_suite(struct kunit_suite *suite) { } + +static inline void kunit_debugfs_destroy_suite(struct kunit_suite *suite) { } + +static inline void kunit_debugfs_init(void) { } + +static inline void kunit_debugfs_cleanup(void) { } + +#endif /* CONFIG_KUNIT_DEBUGFS */ + +#endif /* _KUNIT_DEBUGFS_H */ diff --git a/lib/kunit/kunit-test.c b/lib/kunit/kunit-test.c index ccb8d2e..aceb5bf 100644 --- a/lib/kunit/kunit-test.c +++ b/lib/kunit/kunit-test.c @@ -134,7 +134,7 @@ static void kunit_resource_test_init_resources(struct kunit *test) { struct kunit_test_resource_context *ctx = test->priv;

- kunit_init_test(&ctx->test, "testing_test_init_test"); + kunit_init_test(&ctx->test, "testing_test_init_test", NULL);

KUNIT_EXPECT_TRUE(test, list_empty(&ctx->test.resources)); } @@ -301,7 +301,7 @@ static int kunit_resource_test_init(struct kunit *test)

test->priv = ctx;

- kunit_init_test(&ctx->test, "test_test_context"); + kunit_init_test(&ctx->test, "test_test_context", NULL);

return 0; } diff --git a/lib/kunit/test.c b/lib/kunit/test.c index 9242f93..a3fa21f 100644 --- a/lib/kunit/test.c +++ b/lib/kunit/test.c @@ -10,6 +10,7 @@ #include <linux/kernel.h> #include <linux/sched/debug.h>

+#include "debugfs.h" #include "string-stream.h" #include "try-catch-impl.h"

@@ -28,73 +29,116 @@ static void kunit_print_tap_version(void) } }

-static size_t kunit_test_cases_len(struct kunit_case *test_cases) +/* + * Append formatted message to log, size of which is limited to + * KUNIT_LOG_SIZE bytes (including null terminating byte). + */ +void kunit_log_append(char *log, const char *fmt, ...) +{ + char line[KUNIT_LOG_SIZE]; + va_list args; + int len_left; + + if (!log) + return; + + len_left = KUNIT_LOG_SIZE - strlen(log) - 1; + if (len_left <= 0) + return; + + va_start(args, fmt); + vsnprintf(line, sizeof(line), fmt, args); + va_end(args); + + strncat(log, line, len_left); +} +EXPORT_SYMBOL_GPL(kunit_log_append); + +size_t kunit_suite_num_test_cases(struct kunit_suite *suite) { struct kunit_case *test_case; size_t len = 0;

- for (test_case = test_cases; test_case->run_case; test_case++) + kunit_suite_for_each_test_case(suite, test_case) len++;

return len; } +EXPORT_SYMBOL_GPL(kunit_suite_num_test_cases);

static void kunit_print_subtest_start(struct kunit_suite *suite) { kunit_print_tap_version(); - pr_info("\t# Subtest: %s\n", suite->name); - pr_info("\t1..%zd\n", kunit_test_cases_len(suite->test_cases)); + kunit_log(KERN_INFO, suite, "\t# Subtest: %s", suite->name); + kunit_log(KERN_INFO, suite, "\t1..%zd", + kunit_suite_num_test_cases(suite)); }

-static void kunit_print_ok_not_ok(bool should_indent, +static void kunit_print_ok_not_ok(void *test_or_suite, + bool is_test, bool is_ok, size_t test_number, const char *description) { - const char *indent, *ok_not_ok; - - if (should_indent) - indent = "\t"; - else - indent = ""; + struct kunit_suite *suite = is_test ? NULL : test_or_suite; + struct kunit *test = is_test ? test_or_suite : NULL;

- if (is_ok) - ok_not_ok = "ok"; + /* + * We do not log the test suite results as doing so would + * mean debugfs display would consist of the test suite + * description and status prior to individual test results. + * Hence directly printk the suite status, and we will + * separately seq_printf() the suite status for the debugfs + * representation. + */ + if (suite) + pr_info("%s %zd - %s", + kunit_status_to_string(is_ok), + test_number, description); else - ok_not_ok = "not ok"; - - pr_info("%s%s %zd - %s\n", indent, ok_not_ok, test_number, description); + kunit_log(KERN_INFO, test, "\t%s %zd - %s", + kunit_status_to_string(is_ok), + test_number, description); }

-static bool kunit_suite_has_succeeded(struct kunit_suite *suite) +bool kunit_suite_has_succeeded(struct kunit_suite *suite) { const struct kunit_case *test_case;

- for (test_case = suite->test_cases; test_case->run_case; test_case++) + kunit_suite_for_each_test_case(suite, test_case) { if (!test_case->success) return false; + }

return true; } +EXPORT_SYMBOL_GPL(kunit_suite_has_succeeded);

static void kunit_print_subtest_end(struct kunit_suite *suite) { static size_t kunit_suite_counter = 1;

- kunit_print_ok_not_ok(false, + kunit_print_ok_not_ok((void *)suite, false, kunit_suite_has_succeeded(suite), kunit_suite_counter++, suite->name); }

-static void kunit_print_test_case_ok_not_ok(struct kunit_case *test_case, - size_t test_number) +unsigned int kunit_test_case_num(struct kunit_suite *suite, + struct kunit_case *test_case) { - kunit_print_ok_not_ok(true, - test_case->success, - test_number, - test_case->name); + struct kunit_case *tc; + unsigned int i = 1; + + kunit_suite_for_each_test_case(suite, tc) { + if (tc == test_case) + return i; + i++; + } + + return 0; } +EXPORT_SYMBOL_GPL(kunit_test_case_num);

static void kunit_print_string_stream(struct kunit *test, struct string_stream *stream) @@ -102,6 +146,9 @@ static void kunit_print_string_stream(struct kunit *test, struct string_stream_fragment *fragment; char *buf;

+ if (string_stream_is_empty(stream)) + return; + buf = string_stream_get_string(stream); if (!buf) { kunit_err(test, @@ -175,11 +222,14 @@ void kunit_do_assertion(struct kunit *test, } EXPORT_SYMBOL_GPL(kunit_do_assertion);

-void kunit_init_test(struct kunit *test, const char *name) +void kunit_init_test(struct kunit *test, const char *name, char *log) { spin_lock_init(&test->lock); INIT_LIST_HEAD(&test->resources); test->name = name; + test->log = log; + if (test->log) + test->log[0] = '\0'; test->success = true; } EXPORT_SYMBOL_GPL(kunit_init_test); @@ -290,7 +340,7 @@ static void kunit_run_case_catch_errors(struct kunit_suite *suite, struct kunit_try_catch *try_catch; struct kunit test;

- kunit_init_test(&test, test_case->name); + kunit_init_test(&test, test_case->name, test_case->log); try_catch = &test.try_catch;

kunit_try_catch_init(try_catch, @@ -303,19 +353,20 @@ static void kunit_run_case_catch_errors(struct kunit_suite *suite, kunit_try_catch_run(try_catch, &context);

test_case->success = test.success; + + kunit_print_ok_not_ok(&test, true, test_case->success, + kunit_test_case_num(suite, test_case), + test_case->name); }

int kunit_run_tests(struct kunit_suite *suite) { struct kunit_case *test_case; - size_t test_case_count = 1;

kunit_print_subtest_start(suite);

- for (test_case = suite->test_cases; test_case->run_case; test_case++) { + kunit_suite_for_each_test_case(suite, test_case) kunit_run_case_catch_errors(suite, test_case); - kunit_print_test_case_ok_not_ok(test_case, test_case_count++); - }

kunit_print_subtest_end(suite);

@@ -323,6 +374,37 @@ int kunit_run_tests(struct kunit_suite *suite) } EXPORT_SYMBOL_GPL(kunit_run_tests);

+static void kunit_init_suite(struct kunit_suite *suite) +{ + kunit_debugfs_create_suite(suite); +} + +int __kunit_test_suites_init(struct kunit_suite **suites) +{ + unsigned int i; + + for (i = 0; suites[i] != NULL; i++) { + kunit_init_suite(suites[i]); + kunit_run_tests(suites[i]); + } + return 0; +} +EXPORT_SYMBOL_GPL(__kunit_test_suites_init); + +static void kunit_exit_suite(struct kunit_suite *suite) +{ + kunit_debugfs_destroy_suite(suite); +} + +void __kunit_test_suites_exit(struct kunit_suite **suites) +{ + unsigned int i; + + for (i = 0; suites[i] != NULL; i++) + kunit_exit_suite(suites[i]); +} +EXPORT_SYMBOL_GPL(__kunit_test_suites_exit); + struct kunit_resource *kunit_alloc_and_get_resource(struct kunit *test, kunit_resource_init_t init, kunit_resource_free_t free, @@ -489,12 +571,15 @@ void kunit_cleanup(struct kunit *test)

static int __init kunit_init(void) { + kunit_debugfs_init(); + return 0; } late_initcall(kunit_init);

static void __exit kunit_exit(void) { + kunit_debugfs_cleanup(); } module_exit(kunit_exit);

the logging test ensures multiple strings logged appear in the log string associated with the test when CONFIG_KUNIT_DEBUGFS is enabled.

Signed-off-by: Alan Maguire alan.maguire@oracle.com Reviewed-by: Brendan Higgins brendanhiggins@google.com Reviewed-by: Frank Rowand frank.rowand@sony.com --- lib/kunit/kunit-test.c | 40 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 39 insertions(+), 1 deletion(-)

diff --git a/lib/kunit/kunit-test.c b/lib/kunit/kunit-test.c index aceb5bf..4f3d36a 100644 --- a/lib/kunit/kunit-test.c +++ b/lib/kunit/kunit-test.c @@ -329,6 +329,44 @@ static void kunit_resource_test_exit(struct kunit *test) .exit = kunit_resource_test_exit, .test_cases = kunit_resource_test_cases, }; -kunit_test_suites(&kunit_try_catch_test_suite, &kunit_resource_test_suite); + +static void kunit_log_test(struct kunit *test); + +static struct kunit_case kunit_log_test_cases[] = { + KUNIT_CASE(kunit_log_test), + {} +}; + +static struct kunit_suite kunit_log_test_suite = { + .name = "kunit-log-test", + .test_cases = kunit_log_test_cases, +}; + +static void kunit_log_test(struct kunit *test) +{ + struct kunit_suite *suite = &kunit_log_test_suite; + + kunit_log(KERN_INFO, test, "put this in log."); + kunit_log(KERN_INFO, test, "this too."); + kunit_log(KERN_INFO, suite, "add to suite log."); + kunit_log(KERN_INFO, suite, "along with this."); + +#ifdef CONFIG_KUNIT_DEBUGFS + KUNIT_EXPECT_NOT_ERR_OR_NULL(test, + strstr(test->log, "put this in log.")); + KUNIT_EXPECT_NOT_ERR_OR_NULL(test, + strstr(test->log, "this too.")); + KUNIT_EXPECT_NOT_ERR_OR_NULL(test, + strstr(suite->log, "add to suite log.")); + KUNIT_EXPECT_NOT_ERR_OR_NULL(test, + strstr(suite->log, "along with this.")); +#else + KUNIT_EXPECT_PTR_EQ(test, test->log, (char *)NULL); + KUNIT_EXPECT_PTR_EQ(test, suite->log, (char *)NULL); +#endif +} + +kunit_test_suites(&kunit_try_catch_test_suite, &kunit_resource_test_suite, + &kunit_log_test_suite);

MODULE_LICENSE("GPL v2");

Documentation should describe debugfs layout and semantics.

Signed-off-by: Alan Maguire alan.maguire@oracle.com Reviewed-by: Brendan Higgins brendanhiggins@google.com Reviewed-by: Frank Rowand frank.rowand@sony.com --- Documentation/dev-tools/kunit/usage.rst | 14 ++++++++++++++ 1 file changed, 14 insertions(+)

diff --git a/Documentation/dev-tools/kunit/usage.rst b/Documentation/dev-tools/kunit/usage.rst index 607758a..473a236 100644 --- a/Documentation/dev-tools/kunit/usage.rst +++ b/Documentation/dev-tools/kunit/usage.rst @@ -591,3 +591,17 @@ able to run one test case per invocation.

.. TODO(brendanhiggins@google.com): Add an actual example of an architecture dependent KUnit test. + +KUnit debugfs representation +============================ +When kunit test suites are initialized, they create an associated directory +in /sys/kernel/debug/kunit/<test-suite>. The directory contains one file + +- results: "cat results" displays results of each test case and the results + of the entire suite for the last test run. + +The debugfs representation is primarily of use when kunit test suites are +run in a native environment, either as modules or builtin. Having a way +to display results like this is valuable as otherwise results can be +intermixed with other events in dmesg output. The maximum size of each +results file is KUNIT_LOG_SIZE bytes (defined in include/kunit/test.h).