From aa23c6fbc50c4f9d8b43682f37fc4580a7851413 Mon Sep 17 00:00:00 2001 From: Pranith Kumar Date: Fri, 19 Sep 2014 11:32:29 -0400 Subject: rcutorture: Add early boot self tests Add early boot self tests for RCU under CONFIG_PROVE_RCU. Currently the only test is adding a dummy callback which increments a counter which we then later verify after calling rcu_barrier*(). Signed-off-by: Pranith Kumar Signed-off-by: Paul E. McKenney --- kernel/rcu/rcu.h | 2 ++ kernel/rcu/tiny.c | 4 ++- kernel/rcu/tree.c | 2 ++ kernel/rcu/update.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 91 insertions(+), 1 deletion(-) (limited to 'kernel/rcu') diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h index ff1a6de62f17..07bb02eda844 100644 --- a/kernel/rcu/rcu.h +++ b/kernel/rcu/rcu.h @@ -135,4 +135,6 @@ int rcu_jiffies_till_stall_check(void); */ #define TPS(x) tracepoint_string(x) +void rcu_early_boot_tests(void); + #endif /* __LINUX_RCU_H */ diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c index c0623fc47125..d3d44c589122 100644 --- a/kernel/rcu/tiny.c +++ b/kernel/rcu/tiny.c @@ -380,7 +380,9 @@ void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) } EXPORT_SYMBOL_GPL(call_rcu_bh); -void rcu_init(void) +void __init rcu_init(void) { open_softirq(RCU_SOFTIRQ, rcu_process_callbacks); + + rcu_early_boot_tests(); } diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 9815447d22e0..77b48f03c077 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -3766,6 +3766,8 @@ void __init rcu_init(void) pm_notifier(rcu_pm_notify, 0); for_each_online_cpu(cpu) rcu_cpu_notify(NULL, CPU_UP_PREPARE, (void *)(long)cpu); + + rcu_early_boot_tests(); } #include "tree_plugin.h" diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index 3ef8ba58694e..99d47e6a280f 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -690,3 +690,87 @@ static void rcu_spawn_tasks_kthread(void) } #endif /* #ifdef CONFIG_TASKS_RCU */ + +#ifdef CONFIG_PROVE_RCU + +/* + * Early boot self test parameters, one for each flavor + */ +static bool rcu_self_test; +static bool rcu_self_test_bh; +static bool rcu_self_test_sched; + +module_param(rcu_self_test, bool, 0444); +module_param(rcu_self_test_bh, bool, 0444); +module_param(rcu_self_test_sched, bool, 0444); + +static int rcu_self_test_counter; + +static void test_callback(struct rcu_head *r) +{ + rcu_self_test_counter++; + pr_info("RCU test callback executed %d\n", rcu_self_test_counter); +} + +static void early_boot_test_call_rcu(void) +{ + static struct rcu_head head; + + call_rcu(&head, test_callback); +} + +static void early_boot_test_call_rcu_bh(void) +{ + static struct rcu_head head; + + call_rcu_bh(&head, test_callback); +} + +static void early_boot_test_call_rcu_sched(void) +{ + static struct rcu_head head; + + call_rcu_sched(&head, test_callback); +} + +void rcu_early_boot_tests(void) +{ + pr_info("Running RCU self tests\n"); + + if (rcu_self_test) + early_boot_test_call_rcu(); + if (rcu_self_test_bh) + early_boot_test_call_rcu_bh(); + if (rcu_self_test_sched) + early_boot_test_call_rcu_sched(); +} + +static int rcu_verify_early_boot_tests(void) +{ + int ret = 0; + int early_boot_test_counter = 0; + + if (rcu_self_test) { + early_boot_test_counter++; + rcu_barrier(); + } + if (rcu_self_test_bh) { + early_boot_test_counter++; + rcu_barrier_bh(); + } + if (rcu_self_test_sched) { + early_boot_test_counter++; + rcu_barrier_sched(); + } + + if (rcu_self_test_counter != early_boot_test_counter) { + WARN_ON(1); + ret = -1; + } + + return ret; +} +late_initcall(rcu_verify_early_boot_tests); +#else +void rcu_early_boot_tests(void) {} +#endif /* CONFIG_PROVE_RCU */ -- cgit v1.2.3