From 4137d69124a29506a09756af0aaf0c7acd2a60f6 Mon Sep 17 00:00:00 2001 From: Joel Fernandes Date: Sat, 18 Jul 2026 13:15:32 -0400 Subject: [PATCH] rcu: Remove unused expedited_need_qs field from rcu_state The ->expedited_need_qs counter was part of the old expedited grace-period machinery that spun waiting for each CPU to check in. The current implementation instead tracks holdout CPUs via the rcu_node structures' ->expmask fields and waits on the ->exp_wq[] wait queues, so nothing reads or writes ->expedited_need_qs any longer. Remove the field to avoid wasting space in rcu_state and to keep readers of the expedited code from searching for nonexistent users. Signed-off-by: Joel Fernandes Signed-off-by: Paul E. McKenney --- kernel/rcu/tree.h | 1 - 1 file changed, 1 deletion(-) diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 4069132f9d44..587bd71396ea 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -391,7 +391,6 @@ struct rcu_state { struct mutex exp_mutex; /* Serialize expedited GP. */ struct mutex exp_wake_mutex; /* Serialize wakeup. */ unsigned long expedited_sequence; /* Take a ticket. */ - atomic_t expedited_need_qs; /* # CPUs left to check in. */ struct swait_queue_head expedited_wq; /* Wait for check-ins. */ int ncpus_snap; /* # CPUs seen last time. */ u8 cbovld; /* Callback overload now? */