diff options
| -rw-r--r-- | lib/percpu-refcount.c | 22 |
1 files changed, 4 insertions, 18 deletions
diff --git a/lib/percpu-refcount.c b/lib/percpu-refcount.c index 27fe74948882..8ade009ca2c9 100644 --- a/lib/percpu-refcount.c +++ b/lib/percpu-refcount.c @@ -177,17 +177,11 @@ static void __percpu_ref_switch_to_atomic(struct percpu_ref *ref, call_rcu_sched(&ref->rcu, percpu_ref_switch_to_atomic_rcu); } else if (confirm_switch) { /* - * Somebody already set ATOMIC. Switching may still be in - * progress. @confirm_switch must be invoked after the - * switching is complete and a full sched RCU grace period - * has passed. Wait synchronously for the previous - * switching and schedule @confirm_switch invocation. + * Somebody else already set ATOMIC. Wait for its + * completion and invoke @confirm_switch() directly. */ wait_event(percpu_ref_switch_waitq, !ref->confirm_switch); - ref->confirm_switch = confirm_switch; - - percpu_ref_get(ref); /* put after confirmation */ - call_rcu_sched(&ref->rcu, percpu_ref_call_confirm_rcu); + confirm_switch(ref); } } @@ -211,10 +205,6 @@ static void __percpu_ref_switch_to_atomic(struct percpu_ref *ref, * but it may block if @confirm_kill is specified and @ref is already in * the process of switching to atomic mode. In such cases, @confirm_switch * will be invoked after the switching is complete. - * - * Due to the way percpu_ref is implemented, @confirm_switch will be called - * after at least one full sched RCU grace period has passed but this is an - * implementation detail and must not be depended upon. */ void percpu_ref_switch_to_atomic(struct percpu_ref *ref, percpu_ref_func_t *confirm_switch) @@ -290,11 +280,7 @@ void percpu_ref_switch_to_percpu(struct percpu_ref *ref) * * This function normally doesn't block and can be called from any context * but it may block if @confirm_kill is specified and @ref is in the - * process of switching to atomic mode by percpu_ref_switch_atomic(). - * - * Due to the way percpu_ref is implemented, @confirm_switch will be called - * after at least one full sched RCU grace period has passed but this is an - * implementation detail and must not be depended upon. + * process of switching to atomic mode by percpu_ref_switch_to_atomic(). */ void percpu_ref_kill_and_confirm(struct percpu_ref *ref, percpu_ref_func_t *confirm_kill) |