lib/kunit/debugfs.c

   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(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(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         suite->log = NULL;
 216         kunit_suite_for_each_test_case(suite, test_case) {
 217                 string_stream_destroy(test_case->log);
 218                 test_case->log = NULL;
 219         }
 220 }
 221
 222 void kunit_debugfs_destroy_suite(struct kunit_suite *suite)
 223 {
 224         struct kunit_case *test_case;
 225
 226         debugfs_remove_recursive(suite->debugfs);
 227         string_stream_destroy(suite->log);
 228         kunit_suite_for_each_test_case(suite, test_case)
 229                 string_stream_destroy(test_case->log);
 230 }