From efeff6b39b9de4480572c7b0c5eb77204795cb57 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Thu, 5 Aug 2021 13:28:24 -0700 Subject: rcutorture: Warn on individual rcu_torture_init() error conditions When running rcutorture as a module, any rcu_torture_init() issues will be reflected in the error code from modprobe or insmod, as the case may be. However, these error codes are not available when running rcutorture built-in, for example, when using the kvm.sh script. This commit therefore adds WARN_ON_ONCE() to allow distinguishing rcu_torture_init() errors when running rcutorture built-in. Signed-off-by: Paul E. McKenney --- include/linux/torture.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/linux') diff --git a/include/linux/torture.h b/include/linux/torture.h index 0910c5803f35..24f58e50a94b 100644 --- a/include/linux/torture.h +++ b/include/linux/torture.h @@ -47,6 +47,14 @@ do { \ } while (0) void verbose_torout_sleep(void); +#define torture_init_error(firsterr) \ +({ \ + int ___firsterr = (firsterr); \ + \ + WARN_ONCE(!IS_MODULE(CONFIG_RCU_TORTURE_TEST) && ___firsterr < 0, "Torture-test initialization failed with error code %d\n", ___firsterr); \ + ___firsterr < 0; \ +}) + /* Definitions for online/offline exerciser. */ #ifdef CONFIG_HOTPLUG_CPU int torture_num_online_cpus(void); -- cgit v1.2.3 From a5c071ccfa1728508f31e61213ee795e4529d0d4 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Wed, 28 Jul 2021 12:28:27 -0700 Subject: rcu-tasks: Remove second argument of rcu_read_unlock_trace_special() The second argument of rcu_read_unlock_trace_special() is always zero. When called from exit_tasks_rcu_finish_trace(), it is the constant zero, and rcu_read_unlock_trace_special() doesn't get called from rcu_read_unlock_trace() unless the value of local variable "nesting" is zero because in that case the early return is taken instead. This commit therefore removes the "nesting" argument from the rcu_read_unlock_trace_special() function, substituting the constant zero within that function. This commit also adds a WARN_ON_ONCE() to rcu_read_lock_trace_held() in case non-zeroness some day appears. Signed-off-by: Paul E. McKenney --- include/linux/rcupdate_trace.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/rcupdate_trace.h b/include/linux/rcupdate_trace.h index 86c8f6c98412..6f9c35817398 100644 --- a/include/linux/rcupdate_trace.h +++ b/include/linux/rcupdate_trace.h @@ -31,7 +31,7 @@ static inline int rcu_read_lock_trace_held(void) #ifdef CONFIG_TASKS_TRACE_RCU -void rcu_read_unlock_trace_special(struct task_struct *t, int nesting); +void rcu_read_unlock_trace_special(struct task_struct *t); /** * rcu_read_lock_trace - mark beginning of RCU-trace read-side critical section @@ -80,7 +80,8 @@ static inline void rcu_read_unlock_trace(void) WRITE_ONCE(t->trc_reader_nesting, nesting); return; // We assume shallow reader nesting. } - rcu_read_unlock_trace_special(t, nesting); + WARN_ON_ONCE(nesting != 0); + rcu_read_unlock_trace_special(t); } void call_rcu_tasks_trace(struct rcu_head *rhp, rcu_callback_t func); -- cgit v1.2.3