The following commit has been merged into the core/rcu branch of tip:
Commit-ID: bfba7ed084f8ab0269a5a1d2f51b07865456c334
Gitweb:
https://git.kernel.org/tip/bfba7ed084f8ab0269a5a1d2f51b07865456c334
Author: Uladzislau Rezki (Sony) <ure...@gmail.com>
AuthorDate: Wed, 09 Dec 2020 21:27:32 +01:00
Committer: Paul E. McKenney <paul...@kernel.org>
CommitterDate: Mon, 04 Jan 2021 15:54:49 -08:00
rcu-tasks: Add RCU-tasks self tests
This commit adds self tests for early-boot use of RCU-tasks grace periods.
It tests all three variants (Rude, Tasks, and Tasks Trace) and covers
both synchronous (e.g., synchronize_rcu_tasks()) and asynchronous (e.g.,
call_rcu_tasks()) grace-period APIs.
Self-tests are run only in kernels built with CONFIG_PROVE_RCU=y.
Signed-off-by: Uladzislau Rezki (Sony) <ure...@gmail.com>
[ paulmck: Handle CONFIG_PROVE_RCU=n and identify test cases' callbacks. ]
Signed-off-by: Paul E. McKenney <paul...@kernel.org>
---
kernel/rcu/tasks.h | 79 +++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 79 insertions(+)
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index 73bbe79..74767d3 100644
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -1231,6 +1231,82 @@ void show_rcu_tasks_gp_kthreads(void)
}
#endif /* #ifndef CONFIG_TINY_RCU */
+#ifdef CONFIG_PROVE_RCU
+struct rcu_tasks_test_desc {
+ struct rcu_head rh;
+ const char *name;
+ bool notrun;
+};
+
+static struct rcu_tasks_test_desc tests[] = {
+ {
+ .name = "call_rcu_tasks()",
+ /* If not defined, the test is skipped. */
+ .notrun = !IS_ENABLED(CONFIG_TASKS_RCU),
+ },
+ {
+ .name = "call_rcu_tasks_rude()",
+ /* If not defined, the test is skipped. */
+ .notrun = !IS_ENABLED(CONFIG_TASKS_RUDE_RCU),
+ },
+ {
+ .name = "call_rcu_tasks_trace()",
+ /* If not defined, the test is skipped. */
+ .notrun = !IS_ENABLED(CONFIG_TASKS_TRACE_RCU)
+ }
+};
+
+static void test_rcu_tasks_callback(struct rcu_head *rhp)
+{
+ struct rcu_tasks_test_desc *rttd =
+ container_of(rhp, struct rcu_tasks_test_desc, rh);
+
+ pr_info("Callback from %s invoked.\n", rttd->name);
+
+ rttd->notrun = true;
+}
+
+static void rcu_tasks_initiate_self_tests(void)
+{
+ pr_info("Running RCU-tasks wait API self tests\n");
+#ifdef CONFIG_TASKS_RCU
+ synchronize_rcu_tasks();
+ call_rcu_tasks(&tests[0].rh, test_rcu_tasks_callback);
+#endif
+
+#ifdef CONFIG_TASKS_RUDE_RCU
+ synchronize_rcu_tasks_rude();
+ call_rcu_tasks_rude(&tests[1].rh, test_rcu_tasks_callback);
+#endif
+
+#ifdef CONFIG_TASKS_TRACE_RCU
+ synchronize_rcu_tasks_trace();
+ call_rcu_tasks_trace(&tests[2].rh, test_rcu_tasks_callback);
+#endif
+}
+
+static int rcu_tasks_verify_self_tests(void)
+{
+ int ret = 0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(tests); i++) {
+ if (!tests[i].notrun) { // still hanging.
+ pr_err("%s has been failed.\n", tests[i].name);
+ ret = -1;
+ }
+ }
+
+ if (ret)
+ WARN_ON(1);
+
+ return ret;
+}
+late_initcall(rcu_tasks_verify_self_tests);
+#else /* #ifdef CONFIG_PROVE_RCU */
+static void rcu_tasks_initiate_self_tests(void) { }
+#endif /* #else #ifdef CONFIG_PROVE_RCU */
+
void __init rcu_init_tasks_generic(void)
{
#ifdef CONFIG_TASKS_RCU
@@ -1244,6 +1320,9 @@ void __init rcu_init_tasks_generic(void)
#ifdef CONFIG_TASKS_TRACE_RCU
rcu_spawn_tasks_trace_kthread();
#endif
+
+ // Run the self-tests.
+ rcu_tasks_initiate_self_tests();
}
#else /* #ifdef CONFIG_TASKS_RCU_GENERIC */
