xref: /linux/include/kunit/test-bug.h (revision 056e065a6b6e01ab54bb9770c0d5a15350e571e2)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * KUnit API providing hooks for non-test code to interact with tests.
4  *
5  * Copyright (C) 2020, Google LLC.
6  * Author: Uriel Guajardo <urielguajardo@google.com>
7  */
8 
9 #ifndef _KUNIT_TEST_BUG_H
10 #define _KUNIT_TEST_BUG_H
11 
12 #include <linux/stddef.h> /* for NULL */
13 #include <linux/types.h>  /* for bool */
14 
15 #if IS_ENABLED(CONFIG_KUNIT)
16 
17 #include <linux/jump_label.h> /* For static branch */
18 #include <linux/sched.h>
19 
20 /* Static key if KUnit is running any tests. */
21 DECLARE_STATIC_KEY_FALSE(kunit_running);
22 
23 /* Hooks table: a table of function pointers filled in when kunit loads */
24 extern struct kunit_hooks_table {
25 	__printf(3, 4) void (*fail_current_test)(const char*, int, const char*, ...);
26 	void *(*get_static_stub_address)(struct kunit *test, void *real_fn_addr);
27 	bool (*is_suppressed_warning)(bool count);
28 } kunit_hooks;
29 
30 /**
31  * kunit_get_current_test() - Return a pointer to the currently running
32  *			      KUnit test.
33  *
34  * If a KUnit test is running in the current task, returns a pointer to its
35  * associated struct kunit. This pointer can then be passed to any KUnit
36  * function or assertion. If no test is running (or a test is running in a
37  * different task), returns NULL.
38  *
39  * This function is safe to call even when KUnit is disabled. If CONFIG_KUNIT
40  * is not enabled, it will compile down to nothing and will return quickly no
41  * test is running.
42  */
43 static inline struct kunit *kunit_get_current_test(void)
44 {
45 	if (!static_branch_unlikely(&kunit_running))
46 		return NULL;
47 
48 	return current->kunit_test;
49 }
50 
51 
52 /**
53  * kunit_fail_current_test() - If a KUnit test is running, fail it.
54  *
55  * If a KUnit test is running in the current task, mark that test as failed.
56  */
57 #define kunit_fail_current_test(fmt, ...) do {					\
58 		if (static_branch_unlikely(&kunit_running)) {			\
59 			/* Guaranteed to be non-NULL when kunit_running true*/	\
60 			kunit_hooks.fail_current_test(__FILE__, __LINE__,	\
61 						  fmt, ##__VA_ARGS__);		\
62 		}								\
63 	} while (0)
64 
65 /**
66  * kunit_is_suppressed_warning() - Check if warnings are being suppressed
67  *                                 by the current KUnit test.
68  * @count: if true, increment the suppression counter on match.
69  *
70  * Returns true if the current task has active warning suppression.
71  * Uses the kunit_running static branch for zero overhead when no tests run.
72  *
73  * A single WARN*() may traverse multiple call sites in the warning path
74  * (e.g., __warn_printk() and __report_bug()). Pass @count = true at the
75  * primary suppression point to count each warning exactly once, and
76  * @count = false at secondary points to suppress output without
77  * inflating the count.
78  */
79 static inline bool kunit_is_suppressed_warning(bool count)
80 {
81 	if (!static_branch_unlikely(&kunit_running))
82 		return false;
83 
84 	return kunit_hooks.is_suppressed_warning &&
85 	       kunit_hooks.is_suppressed_warning(count);
86 }
87 
88 #else
89 
90 static inline struct kunit *kunit_get_current_test(void) { return NULL; }
91 static inline bool kunit_is_suppressed_warning(bool count) { return false; }
92 
93 #define kunit_fail_current_test(fmt, ...) do {} while (0)
94 
95 #endif
96 
97 #endif /* _KUNIT_TEST_BUG_H */
98