linux-stable/lib/kunit/try-catch.c
Alan Maguire 1c024d4515 kunit: remove timeout dependence on sysctl_hung_task_timeout_seconds
In discussion of how to handle timeouts, it was noted that if
sysctl_hung_task_timeout_seconds is exceeded for a kunit test,
the test task will be killed and an oops generated.  This should
suffice as a means of debugging such timeout issues for now.

Hence remove use of sysctl_hung_task_timeout_secs, which has the
added benefit of avoiding the need to export that symbol from
the core kernel.

Co-developed-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2020-01-09 16:42:55 -07:00

97 lines
2.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* An API to allow a function, that may fail, to be executed, and recover in a
* controlled manner.
*
* Copyright (C) 2019, Google LLC.
* Author: Brendan Higgins <brendanhiggins@google.com>
*/
#include <kunit/test.h>
#include <linux/completion.h>
#include <linux/kernel.h>
#include <linux/kthread.h>
#include "try-catch-impl.h"
void __noreturn kunit_try_catch_throw(struct kunit_try_catch *try_catch)
{
try_catch->try_result = -EFAULT;
complete_and_exit(try_catch->try_completion, -EFAULT);
}
EXPORT_SYMBOL_GPL(kunit_try_catch_throw);
static int kunit_generic_run_threadfn_adapter(void *data)
{
struct kunit_try_catch *try_catch = data;
try_catch->try(try_catch->context);
complete_and_exit(try_catch->try_completion, 0);
}
static unsigned long kunit_test_timeout(void)
{
/*
* TODO(brendanhiggins@google.com): We should probably have some type of
* variable timeout here. The only question is what that timeout value
* should be.
*
* The intention has always been, at some point, to be able to label
* tests with some type of size bucket (unit/small, integration/medium,
* large/system/end-to-end, etc), where each size bucket would get a
* default timeout value kind of like what Bazel does:
* https://docs.bazel.build/versions/master/be/common-definitions.html#test.size
* There is still some debate to be had on exactly how we do this. (For
* one, we probably want to have some sort of test runner level
* timeout.)
*
* For more background on this topic, see:
* https://mike-bland.com/2011/11/01/small-medium-large.html
*
* If tests timeout due to exceeding sysctl_hung_task_timeout_secs,
* the task will be killed and an oops generated.
*/
return 300 * MSEC_PER_SEC; /* 5 min */
}
void kunit_try_catch_run(struct kunit_try_catch *try_catch, void *context)
{
DECLARE_COMPLETION_ONSTACK(try_completion);
struct kunit *test = try_catch->test;
struct task_struct *task_struct;
int exit_code, time_remaining;
try_catch->context = context;
try_catch->try_completion = &try_completion;
try_catch->try_result = 0;
task_struct = kthread_run(kunit_generic_run_threadfn_adapter,
try_catch,
"kunit_try_catch_thread");
if (IS_ERR(task_struct)) {
try_catch->catch(try_catch->context);
return;
}
time_remaining = wait_for_completion_timeout(&try_completion,
kunit_test_timeout());
if (time_remaining == 0) {
kunit_err(test, "try timed out\n");
try_catch->try_result = -ETIMEDOUT;
}
exit_code = try_catch->try_result;
if (!exit_code)
return;
if (exit_code == -EFAULT)
try_catch->try_result = 0;
else if (exit_code == -EINTR)
kunit_err(test, "wake_up_process() was never called\n");
else if (exit_code)
kunit_err(test, "Unknown error: %d\n", exit_code);
try_catch->catch(try_catch->context);
}
EXPORT_SYMBOL_GPL(kunit_try_catch_run);