Unconfuse a bit the name of this function which suggests returning true when the state is updated. It actually returns true when the rdp is in the process of deoffloading and we must ignore it.
Reported-by: Paul E. McKenney paulmck@kernel.org Cc: Josh Triplett josh@joshtriplett.org Cc: Lai Jiangshan jiangshanlai@gmail.com Cc: Joel Fernandes joel@joelfernandes.org Cc: Neeraj Upadhyay neeraju@codeaurora.org Cc: Boqun Feng boqun.feng@gmail.com Signed-off-by: Frederic Weisbecker frederic@kernel.org --- kernel/rcu/tree_plugin.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 53ff99a18ab1..86c3bcceede6 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -2026,7 +2026,8 @@ static inline bool nocb_gp_enabled_cb(struct rcu_data *rdp) return rcu_segcblist_test_flags(&rdp->cblist, flags); }
-static inline bool nocb_gp_update_state(struct rcu_data *rdp, bool *needwake_state) +static inline bool nocb_gp_update_state_deoffloading(struct rcu_data *rdp, + bool *needwake_state) { struct rcu_segcblist *cblist = &rdp->cblist;
@@ -2036,7 +2037,7 @@ static inline bool nocb_gp_update_state(struct rcu_data *rdp, bool *needwake_sta if (rcu_segcblist_test_flags(cblist, SEGCBLIST_KTHREAD_CB)) *needwake_state = true; } - return true; + return false; }
/* @@ -2047,7 +2048,7 @@ static inline bool nocb_gp_update_state(struct rcu_data *rdp, bool *needwake_sta rcu_segcblist_clear_flags(cblist, SEGCBLIST_KTHREAD_GP); if (!rcu_segcblist_test_flags(cblist, SEGCBLIST_KTHREAD_CB)) *needwake_state = true; - return false; + return true; }
@@ -2085,7 +2086,7 @@ static void nocb_gp_wait(struct rcu_data *my_rdp) continue; trace_rcu_nocb_wake(rcu_state.name, rdp->cpu, TPS("Check")); rcu_nocb_lock_irqsave(rdp, flags); - if (!nocb_gp_update_state(rdp, &needwake_state)) { + if (nocb_gp_update_state_deoffloading(rdp, &needwake_state)) { rcu_nocb_unlock_irqrestore(rdp, flags); if (needwake_state) swake_up_one(&rdp->nocb_state_wq);