The following commit has been merged into the core/rcu branch of tip: Commit-ID: 66777e5821f6e672003fde697b8489402bb5aa98 Gitweb: https://git.kernel.org/tip/66777e5821f6e672003fde697b8489402bb5aa98 Author: Paul E. McKenney <paulmck@xxxxxxxxxx> AuthorDate: Mon, 16 Mar 2020 15:22:44 -07:00 Committer: Paul E. McKenney <paulmck@xxxxxxxxxx> CommitterDate: Mon, 27 Apr 2020 11:03:50 -07:00 rcu-tasks: Use context-switch hook for PREEMPT=y kernels Currently, the PREEMPT=y version of rcu_note_context_switch() does not invoke rcu_tasks_qs(), and we need it to in order to keep RCU Tasks Trace's IPIs down to a dull roar. This commit therefore enables this hook. Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx> --- kernel/rcu/tree_plugin.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 088e84e..4f34c32 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -331,6 +331,8 @@ void rcu_note_context_switch(bool preempt) rcu_qs(); if (rdp->exp_deferred_qs) rcu_report_exp_rdp(rdp); + if (!preempt) + rcu_tasks_qs(current); trace_rcu_utilization(TPS("End context switch")); } EXPORT_SYMBOL_GPL(rcu_note_context_switch);