Add functionality to run built-in tests after boot by writing to a debugfs file.
Add a new debugfs file labeled "run" for each test suite to use for this purpose.
As an example, write to the file using the following:
echo "any string" > /sys/kernel/debugfs/kunit/<testsuite>/run
This will trigger the test suite to run and will print results to the kernel log.
To guard against running tests concurrently with this feature, add a mutex lock around running kunit. This supports the current practice of not allowing tests to be run concurrently on the same kernel.
This new functionality could be used to design a parameter injection feature in the future.
Signed-off-by: Rae Moar rmoar@google.com --- Changes since v4: - Rebased series causing a few small changes in debugfs.c in this patch
lib/kunit/debugfs.c | 68 +++++++++++++++++++++++++++++++++++++++++++++ lib/kunit/test.c | 10 +++++++ 2 files changed, 78 insertions(+)
diff --git a/lib/kunit/debugfs.c b/lib/kunit/debugfs.c index 382706dfb47d..d548750a325a 100644 --- a/lib/kunit/debugfs.c +++ b/lib/kunit/debugfs.c @@ -8,12 +8,14 @@ #include <linux/module.h>
#include <kunit/test.h> +#include <kunit/test-bug.h>
#include "string-stream.h" #include "debugfs.h"
#define KUNIT_DEBUGFS_ROOT "kunit" #define KUNIT_DEBUGFS_RESULTS "results" +#define KUNIT_DEBUGFS_RUN "run"
/* * Create a debugfs representation of test suites: @@ -21,6 +23,8 @@ * Path Semantics * /sys/kernel/debug/kunit/<testsuite>/results Show results of last run for * testsuite + * /sys/kernel/debug/kunit/<testsuite>/run Write to this file to trigger + * testsuite to run * */
@@ -101,6 +105,51 @@ static int debugfs_results_open(struct inode *inode, struct file *file) return single_open(file, debugfs_print_results, suite); }
+/* + * Print a usage message to the debugfs "run" file + * (/sys/kernel/debug/kunit/<testsuite>/run) if opened. + */ +static int debugfs_print_run(struct seq_file *seq, void *v) +{ + struct kunit_suite *suite = (struct kunit_suite *)seq->private; + + seq_puts(seq, "Write to this file to trigger the test suite to run.\n"); + seq_printf(seq, "usage: echo "any string" > /sys/kernel/debugfs/kunit/%s/run\n", + suite->name); + return 0; +} + +/* + * The debugfs "run" file (/sys/kernel/debug/kunit/<testsuite>/run) + * contains no information. Write to the file to trigger the test suite + * to run. + */ +static int debugfs_run_open(struct inode *inode, struct file *file) +{ + struct kunit_suite *suite; + + suite = (struct kunit_suite *)inode->i_private; + + return single_open(file, debugfs_print_run, suite); +} + +/* + * Trigger a test suite to run by writing to the suite's "run" debugfs + * file found at: /sys/kernel/debug/kunit/<testsuite>/run + * + * Note: what is written to this file will not be saved. + */ +static ssize_t debugfs_run(struct file *file, + const char __user *buf, size_t count, loff_t *ppos) +{ + struct inode *f_inode = file->f_inode; + struct kunit_suite *suite = (struct kunit_suite *) f_inode->i_private; + + __kunit_test_suites_init(&suite, 1); + + return count; +} + static const struct file_operations debugfs_results_fops = { .open = debugfs_results_open, .read = seq_read, @@ -108,11 +157,23 @@ static const struct file_operations debugfs_results_fops = { .release = debugfs_release, };
+static const struct file_operations debugfs_run_fops = { + .open = debugfs_run_open, + .read = seq_read, + .write = debugfs_run, + .llseek = seq_lseek, + .release = debugfs_release, +}; + void kunit_debugfs_create_suite(struct kunit_suite *suite) { struct kunit_case *test_case; struct string_stream *stream;
+ /* If suite log already allocated, do not create new debugfs files. */ + if (suite->log) + return; + /* * Allocate logs before creating debugfs representation. * The suite->log and test_case->log pointer are expected to be NULL @@ -140,6 +201,13 @@ void kunit_debugfs_create_suite(struct kunit_suite *suite) debugfs_create_file(KUNIT_DEBUGFS_RESULTS, S_IFREG | 0444, suite->debugfs, suite, &debugfs_results_fops); + + /* Do not create file to re-run test if test runs on init */ + if (!suite->is_init) { + debugfs_create_file(KUNIT_DEBUGFS_RUN, S_IFREG | 0644, + suite->debugfs, + suite, &debugfs_run_fops); + } return;
err: diff --git a/lib/kunit/test.c b/lib/kunit/test.c index 6c082911a85f..a52fcb9a4457 100644 --- a/lib/kunit/test.c +++ b/lib/kunit/test.c @@ -13,6 +13,7 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/moduleparam.h> +#include <linux/mutex.h> #include <linux/panic.h> #include <linux/sched/debug.h> #include <linux/sched.h> @@ -22,6 +23,8 @@ #include "string-stream.h" #include "try-catch-impl.h"
+static DEFINE_MUTEX(kunit_run_lock); + /* * Hook to fail the current test and print an error message to the log. */ @@ -654,6 +657,7 @@ static void kunit_init_suite(struct kunit_suite *suite) kunit_debugfs_create_suite(suite); suite->status_comment[0] = '\0'; suite->suite_init_err = 0; + string_stream_clear(suite->log); }
bool kunit_enabled(void) @@ -670,6 +674,11 @@ int __kunit_test_suites_init(struct kunit_suite * const * const suites, int num_ return 0; }
+ /* Use mutex lock to guard against running tests concurrently. */ + if (mutex_lock_interruptible(&kunit_run_lock)) { + pr_err("kunit: test interrupted\n"); + return -EINTR; + } static_branch_inc(&kunit_running);
for (i = 0; i < num_suites; i++) { @@ -678,6 +687,7 @@ int __kunit_test_suites_init(struct kunit_suite * const * const suites, int num_ }
static_branch_dec(&kunit_running); + mutex_unlock(&kunit_run_lock); return 0; } EXPORT_SYMBOL_GPL(__kunit_test_suites_init);