xref: /linux/lib/kunit/debugfs.c (revision 906fd46a65383cd639e5eec72a047efc33045d86)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2020, Oracle and/or its affiliates.
4  *    Author: Alan Maguire <alan.maguire@oracle.com>
5  */
6 
7 #include <linux/debugfs.h>
8 #include <linux/module.h>
9 
10 #include <kunit/test.h>
11 #include <kunit/test-bug.h>
12 
13 #include "string-stream.h"
14 #include "debugfs.h"
15 
16 #define KUNIT_DEBUGFS_ROOT             "kunit"
17 #define KUNIT_DEBUGFS_RESULTS          "results"
18 #define KUNIT_DEBUGFS_RUN              "run"
19 
20 /*
21  * Create a debugfs representation of test suites:
22  *
23  * Path						Semantics
24  * /sys/kernel/debug/kunit/<testsuite>/results	Show results of last run for
25  *						testsuite
26  * /sys/kernel/debug/kunit/<testsuite>/run	Write to this file to trigger
27  *						testsuite to run
28  *
29  */
30 
31 static struct dentry *debugfs_rootdir;
32 
33 void kunit_debugfs_cleanup(void)
34 {
35 	debugfs_remove_recursive(debugfs_rootdir);
36 }
37 
38 void kunit_debugfs_init(void)
39 {
40 	if (!debugfs_rootdir)
41 		debugfs_rootdir = debugfs_create_dir(KUNIT_DEBUGFS_ROOT, NULL);
42 }
43 
44 static void debugfs_print_result(struct seq_file *seq, struct string_stream *log)
45 {
46 	struct string_stream_fragment *frag_container;
47 
48 	if (!log)
49 		return;
50 
51 	/*
52 	 * Walk the fragments so we don't need to allocate a temporary
53 	 * buffer to hold the entire string.
54 	 */
55 	spin_lock(&log->lock);
56 	list_for_each_entry(frag_container, &log->fragments, node)
57 		seq_printf(seq, "%s", frag_container->fragment);
58 	spin_unlock(&log->lock);
59 }
60 
61 /*
62  * /sys/kernel/debug/kunit/<testsuite>/results shows all results for testsuite.
63  */
64 static int debugfs_print_results(struct seq_file *seq, void *v)
65 {
66 	struct kunit_suite *suite = (struct kunit_suite *)seq->private;
67 	enum kunit_status success;
68 	struct kunit_case *test_case;
69 
70 	if (!suite)
71 		return 0;
72 
73 	success = kunit_suite_has_succeeded(suite);
74 
75 	/* Print KTAP header so the debugfs log can be parsed as valid KTAP. */
76 	seq_puts(seq, "KTAP version 1\n");
77 	seq_puts(seq, "1..1\n");
78 
79 	/* Print suite header because it is not stored in the test logs. */
80 	seq_puts(seq, KUNIT_SUBTEST_INDENT "KTAP version 1\n");
81 	seq_printf(seq, KUNIT_SUBTEST_INDENT "# Subtest: %s\n", suite->name);
82 	seq_printf(seq, KUNIT_SUBTEST_INDENT "1..%zd\n", kunit_suite_num_test_cases(suite));
83 
84 	kunit_suite_for_each_test_case(suite, test_case)
85 		debugfs_print_result(seq, test_case->log);
86 
87 	debugfs_print_result(seq, suite->log);
88 
89 	seq_printf(seq, "%s %d %s\n",
90 		   kunit_status_to_ok_not_ok(success), 1, suite->name);
91 	return 0;
92 }
93 
94 static int debugfs_release(struct inode *inode, struct file *file)
95 {
96 	return single_release(inode, file);
97 }
98 
99 static int debugfs_results_open(struct inode *inode, struct file *file)
100 {
101 	struct kunit_suite *suite;
102 
103 	suite = (struct kunit_suite *)inode->i_private;
104 
105 	return single_open(file, debugfs_print_results, suite);
106 }
107 
108 /*
109  * Print a usage message to the debugfs "run" file
110  * (/sys/kernel/debug/kunit/<testsuite>/run) if opened.
111  */
112 static int debugfs_print_run(struct seq_file *seq, void *v)
113 {
114 	struct kunit_suite *suite = (struct kunit_suite *)seq->private;
115 
116 	seq_puts(seq, "Write to this file to trigger the test suite to run.\n");
117 	seq_printf(seq, "usage: echo \"any string\" > /sys/kernel/debugfs/kunit/%s/run\n",
118 			suite->name);
119 	return 0;
120 }
121 
122 /*
123  * The debugfs "run" file (/sys/kernel/debug/kunit/<testsuite>/run)
124  * contains no information. Write to the file to trigger the test suite
125  * to run.
126  */
127 static int debugfs_run_open(struct inode *inode, struct file *file)
128 {
129 	struct kunit_suite *suite;
130 
131 	suite = (struct kunit_suite *)inode->i_private;
132 
133 	return single_open(file, debugfs_print_run, suite);
134 }
135 
136 /*
137  * Trigger a test suite to run by writing to the suite's "run" debugfs
138  * file found at: /sys/kernel/debug/kunit/<testsuite>/run
139  *
140  * Note: what is written to this file will not be saved.
141  */
142 static ssize_t debugfs_run(struct file *file,
143 		const char __user *buf, size_t count, loff_t *ppos)
144 {
145 	struct inode *f_inode = file->f_inode;
146 	struct kunit_suite *suite = (struct kunit_suite *) f_inode->i_private;
147 
148 	__kunit_test_suites_init(&suite, 1);
149 
150 	return count;
151 }
152 
153 static const struct file_operations debugfs_results_fops = {
154 	.open = debugfs_results_open,
155 	.read = seq_read,
156 	.llseek = seq_lseek,
157 	.release = debugfs_release,
158 };
159 
160 static const struct file_operations debugfs_run_fops = {
161 	.open = debugfs_run_open,
162 	.read = seq_read,
163 	.write = debugfs_run,
164 	.llseek = seq_lseek,
165 	.release = debugfs_release,
166 };
167 
168 void kunit_debugfs_create_suite(struct kunit_suite *suite)
169 {
170 	struct kunit_case *test_case;
171 	struct string_stream *stream;
172 
173 	/* If suite log already allocated, do not create new debugfs files. */
174 	if (suite->log)
175 		return;
176 
177 	/*
178 	 * Allocate logs before creating debugfs representation.
179 	 * The suite->log and test_case->log pointer are expected to be NULL
180 	 * if there isn't a log, so only set it if the log stream was created
181 	 * successfully.
182 	 */
183 	stream = alloc_string_stream(GFP_KERNEL);
184 	if (IS_ERR_OR_NULL(stream))
185 		return;
186 
187 	string_stream_set_append_newlines(stream, true);
188 	suite->log = stream;
189 
190 	kunit_suite_for_each_test_case(suite, test_case) {
191 		stream = alloc_string_stream(GFP_KERNEL);
192 		if (IS_ERR_OR_NULL(stream))
193 			goto err;
194 
195 		string_stream_set_append_newlines(stream, true);
196 		test_case->log = stream;
197 	}
198 
199 	suite->debugfs = debugfs_create_dir(suite->name, debugfs_rootdir);
200 
201 	debugfs_create_file(KUNIT_DEBUGFS_RESULTS, S_IFREG | 0444,
202 			    suite->debugfs,
203 			    suite, &debugfs_results_fops);
204 
205 	/* Do not create file to re-run test if test runs on init */
206 	if (!suite->is_init) {
207 		debugfs_create_file(KUNIT_DEBUGFS_RUN, S_IFREG | 0644,
208 				    suite->debugfs,
209 				    suite, &debugfs_run_fops);
210 	}
211 	return;
212 
213 err:
214 	string_stream_destroy(suite->log);
215 	kunit_suite_for_each_test_case(suite, test_case)
216 		string_stream_destroy(test_case->log);
217 }
218 
219 void kunit_debugfs_destroy_suite(struct kunit_suite *suite)
220 {
221 	struct kunit_case *test_case;
222 
223 	debugfs_remove_recursive(suite->debugfs);
224 	string_stream_destroy(suite->log);
225 	kunit_suite_for_each_test_case(suite, test_case)
226 		string_stream_destroy(test_case->log);
227 }
228