Commit c72a8709 authored by Rae Moar's avatar Rae Moar Committed by Shuah Khan
Browse files

kunit: add ability to run tests after boot using debugfs 



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.

Fixed up merge conflict duing rebase to Linux 6.7-rc6
Signed-off-by: default avatarShuah Khan <skhan@linuxfoundation.org>

Reviewed-by: default avatarDavid Gow <davidgow@google.com>
Signed-off-by: default avatarRae Moar <rmoar@google.com>
Signed-off-by: default avatarShuah Khan <skhan@linuxfoundation.org>
parent 6c4ea2f4

lib/kunit/debugfs.c

+68 −0
Original line number Diff line number Diff line
@@ -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:

lib/kunit/test.c

+10 −0
Original line number Diff line number Diff line
@@ -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.

 */
@@ -692,6 +695,7 @@ 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)
@@ -710,6 +714,11 @@ int __kunit_test_suites_init(struct kunit_suite * const * const suites, int num_ 


	kunit_suite_counter = 1;



	/* 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++) {
@@ -718,6 +727,7 @@ 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);