1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * An API to allow a function, that may fail, to be executed, and recover in a |
4 | * controlled manner. |
5 | * |
6 | * Copyright (C) 2019, Google LLC. |
7 | * Author: Brendan Higgins <brendanhiggins@google.com> |
8 | */ |
9 | |
10 | #include <kunit/test.h> |
11 | #include <linux/completion.h> |
12 | #include <linux/kernel.h> |
13 | #include <linux/kthread.h> |
14 | |
15 | #include "try-catch-impl.h" |
16 | |
17 | void __noreturn kunit_try_catch_throw(struct kunit_try_catch *try_catch) |
18 | { |
19 | try_catch->try_result = -EFAULT; |
20 | kthread_complete_and_exit(try_catch->try_completion, -EFAULT); |
21 | } |
22 | EXPORT_SYMBOL_GPL(kunit_try_catch_throw); |
23 | |
24 | static int kunit_generic_run_threadfn_adapter(void *data) |
25 | { |
26 | struct kunit_try_catch *try_catch = data; |
27 | |
28 | try_catch->try(try_catch->context); |
29 | |
30 | kthread_complete_and_exit(try_catch->try_completion, 0); |
31 | } |
32 | |
33 | static unsigned long kunit_test_timeout(void) |
34 | { |
35 | /* |
36 | * TODO(brendanhiggins@google.com): We should probably have some type of |
37 | * variable timeout here. The only question is what that timeout value |
38 | * should be. |
39 | * |
40 | * The intention has always been, at some point, to be able to label |
41 | * tests with some type of size bucket (unit/small, integration/medium, |
42 | * large/system/end-to-end, etc), where each size bucket would get a |
43 | * default timeout value kind of like what Bazel does: |
44 | * https://docs.bazel.build/versions/master/be/common-definitions.html#test.size |
45 | * There is still some debate to be had on exactly how we do this. (For |
46 | * one, we probably want to have some sort of test runner level |
47 | * timeout.) |
48 | * |
49 | * For more background on this topic, see: |
50 | * https://mike-bland.com/2011/11/01/small-medium-large.html |
51 | * |
52 | * If tests timeout due to exceeding sysctl_hung_task_timeout_secs, |
53 | * the task will be killed and an oops generated. |
54 | */ |
55 | return 300 * msecs_to_jiffies(MSEC_PER_SEC); /* 5 min */ |
56 | } |
57 | |
58 | void kunit_try_catch_run(struct kunit_try_catch *try_catch, void *context) |
59 | { |
60 | DECLARE_COMPLETION_ONSTACK(try_completion); |
61 | struct kunit *test = try_catch->test; |
62 | struct task_struct *task_struct; |
63 | int exit_code, time_remaining; |
64 | |
65 | try_catch->context = context; |
66 | try_catch->try_completion = &try_completion; |
67 | try_catch->try_result = 0; |
68 | task_struct = kthread_run(kunit_generic_run_threadfn_adapter, |
69 | try_catch, |
70 | "kunit_try_catch_thread" ); |
71 | if (IS_ERR(ptr: task_struct)) { |
72 | try_catch->catch(try_catch->context); |
73 | return; |
74 | } |
75 | |
76 | time_remaining = wait_for_completion_timeout(x: &try_completion, |
77 | timeout: kunit_test_timeout()); |
78 | if (time_remaining == 0) { |
79 | kunit_err(test, "try timed out\n" ); |
80 | try_catch->try_result = -ETIMEDOUT; |
81 | kthread_stop(k: task_struct); |
82 | } |
83 | |
84 | exit_code = try_catch->try_result; |
85 | |
86 | if (!exit_code) |
87 | return; |
88 | |
89 | if (exit_code == -EFAULT) |
90 | try_catch->try_result = 0; |
91 | else if (exit_code == -EINTR) |
92 | kunit_err(test, "wake_up_process() was never called\n" ); |
93 | else if (exit_code) |
94 | kunit_err(test, "Unknown error: %d\n" , exit_code); |
95 | |
96 | try_catch->catch(try_catch->context); |
97 | } |
98 | EXPORT_SYMBOL_GPL(kunit_try_catch_run); |
99 | |