On Tue, Feb 11, 2025 at 6:37 AM Petr Mladek pmladek@suse.com wrote:
On Mon 2025-02-10 13:13:48, Tamir Duberstein wrote:
Convert the scanf() self-test to a KUnit test.
In the interest of keeping the patch reasonably-sized this doesn't refactor the tests into proper parameterized tests - it's all one big test case.
Acked-by: Petr Mladek pmladek@suse.com
Please, remove this. The patchset has changed a lot and it is not longer true.
Will do.
--- a/lib/test_scanf.c +++ b/lib/scanf_kunit.c @@ -15,67 +13,49 @@
[...]
#define _check_numbers_template(arg_fmt, expect, str, fmt, n_args, ap) \ do { \
pr_debug("\"%s\", \"%s\" ->\n", str, fmt); \
kunit_printk(KERN_DEBUG, test, "\"%s\", \"%s\" ->", str, fmt); \The switch from pr_debug() to kunit_printk() causes printing huge amount of messages even when the test passes.
I'm not able to reproduce this. pr_debug expands to printk(KERN_DEBUG, ...) which is also what kunit_printk(KERN_DEBUG, ...) expands to. Can you help me understand how you're testing?
[ 5780.664377] KTAP version 1 [ 5780.664891] 1..1 [ 5780.665376] KTAP version 1 [ 5780.665765] # Subtest: scanf [ 5780.666104] # module: scanf_kunit [ 5780.666112] 1..10 [ 5780.667354] # numbers_simple: "0", "%llu" -> [ 5780.667371] # numbers_simple: 0 [ 5780.667923] # numbers_simple: "0", "%llu" -> [ 5780.668321] # numbers_simple: 0 [ 5780.668803] # numbers_simple: "1", "%llu" -> [ 5780.669175] # numbers_simple: 1 [ 5780.669624] # numbers_simple: "18446744073709551615", "%llu" ->
[... skipping 7500+ lines ...]
[ 5783.157777] # test_simple_strtol: simple_strtol("0x7fffffffffffffff", 0) -> 0x7fffffffffffffff [ 5783.158229] # test_simple_strtol: simple_strtol("0x8000000000000001", 0) -> 0x8000000000000001 [ 5783.158683] # test_simple_strtol: simple_strtol("0x8000000000000000", 0) -> 0x8000000000000000 [ 5783.159131] # test_simple_strtol: simple_strtol("0x8000000000000000", 0) -> 0x8000000000000000 [ 5783.159586] # test_simple_strtol: simple_strtol("0x8000000000000001", 0) -> 0x8000000000000001 [ 5783.160048] # test_simple_strtol: simple_strtol("0x7fffffffffffffff", 0) -> 0x7fffffffffffffff [ 5783.160506] # test_simple_strtol: simple_strtol("0xfffffffffffffffe", 0) -> 0xfffffffffffffffe [ 5783.160957] # test_simple_strtol: simple_strtol("0x2", 0) -> 0x2 [ 5783.161467] # test_simple_strtol: simple_strtol("0xffffffffffffffff", 0) -> 0xffffffffffffffff [ 5783.161806] # test_simple_strtol: simple_strtol("0x1", 0) -> 0x1 [ 5783.162564] ok 10 test_simple_strtol [ 5783.163145] # scanf: pass:10 fail:0 skip:0 total:10 [ 5783.163537] # Totals: pass:22 fail:0 skip:0 total:22 [ 5783.164052] ok 1 scanf
Yes, it would help with debugging. But we should print these details only when the test fails!
Partial solution might be to use pr_debug(). The messages will be disabled by default and can be enabled via /sys/kernel/debug/dynamic_debug/control
Here is some POC:
From 7ea79fd67c4a7d8dff9d9fa986bb8dc037087c47 Mon Sep 17 00:00:00 2001 From: Petr Mladek pmladek@suse.com Date: Tue, 11 Feb 2025 12:24:40 +0100 Subject: [POC] kunit/scanf_knunit: Add kunit_debug() to allow using the dynamic debug facility
Do not fill the kernel logbuffer with debug messages by default. Allow to enable them via /sys/kernel/debug/dynamic_debug/control
The question is whether we want to print them into the kunit log.
FIXME: This use just a POC. The right solution should reduce cut&paste.
include/kunit/test.h | 30 ++++++++++++++++++++++++++++++ lib/scanf_kunit.c | 6 +++--- 2 files changed, 33 insertions(+), 3 deletions(-)
diff --git a/include/kunit/test.h b/include/kunit/test.h index 58dbab60f853..23fa3d6b3735 100644 --- a/include/kunit/test.h +++ b/include/kunit/test.h @@ -637,6 +637,36 @@ void __printf(2, 3) kunit_log_append(struct string_stream *log, const char *fmt, #define kunit_err(test, fmt, ...) \ kunit_printk(KERN_ERR, test, fmt, ##__VA_ARGS__)
+/*
- pr_debug 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.
- The special variant is needed to allow using the printk dynamic debug
- infrastructure, see CONFIG_DYNAMIC_DEBUG.
- */
+#define kunit_log_debug(test_or_suite, fmt, ...) \
do { \pr_debug(fmt, ##__VA_ARGS__); \kunit_log_append((test_or_suite)->log, fmt, \##__VA_ARGS__); \} while (0)+#define kunit_printk_debug(test, fmt, ...) \
kunit_log_debug(test, KUNIT_SUBTEST_INDENT "# %s: " fmt, \(test)->name, ##__VA_ARGS__)+/**
- kunit_debug() - Prints an DEBUG level message associated with @test.
- @test: The test context object.
- @fmt: A printk() style format string.
- Prints an error level message.
- */
+#define kunit_debug(test, fmt, ...) \
kunit_printk_debug(test, fmt, ##__VA_ARGS__)/*
- Must be called at the beginning of each KUNIT_*_ASSERTION().
- Cf. KUNIT_CURRENT_LOC.
diff --git a/lib/scanf_kunit.c b/lib/scanf_kunit.c index 7e2e7d891e41..e45f3c4f0437 100644 --- a/lib/scanf_kunit.c +++ b/lib/scanf_kunit.c @@ -42,10 +42,10 @@ _test(struct kunit *test, check_fn fn, const void *check_data, const char *strin
#define _check_numbers_template(arg_fmt, expect, str, fmt, n_args, ap) \ do { \
kunit_printk(KERN_DEBUG, test, "\"%s\", \"%s\" ->", str, fmt); \
kunit_debug(test, "\"%s\", \"%s\" ->", str, fmt); \ for (; n_args > 0; n_args--, expect++) { \ typeof(*expect) got = *va_arg(ap, typeof(expect)); \
kunit_printk(KERN_DEBUG, test, "\t" arg_fmt, got); \
kunit_debug(test, "\t" arg_fmt, got); \ KUNIT_EXPECT_EQ_MSG(test, got, *expect, \ "vsscanf(\"%s\", \"%s\", ...)", str, fmt); \ } \@@ -677,7 +677,7 @@ do { \ \ len = snprintf(test_buffer, BUF_SIZE, gen_fmt, expect); \ got = (fn)(test_buffer, &endp, base); \
kunit_printk(KERN_DEBUG, test, #fn "(\"%s\", %d) -> " gen_fmt, test_buffer, base, got); \
kunit_debug(test, #fn "(\"%s\", %d) -> " gen_fmt, test_buffer, base, got); \ if (got != (expect)) { \ KUNIT_FAIL(test, #fn "(\"%s\", %d): got " gen_fmt " expected " gen_fmt, \ test_buffer, base, got, expect); \-- 2.48.1
But when thinking more about it. I think that even pr_debug() is not the right solution.
IMHO, we really want to print these details only when the test fails.
Best Regards, Petr
If you use one of the kunit userspace helpers, you will only see the output when the test fails. Having said that, in my local testing I don't see the KERN_DEBUG prints locally. I had to run with ignore_loglevel to see them at all.