From 462df2f543ae360e79fcaa1b498d2a1a0c2a5b63 Mon Sep 17 00:00:00 2001 From: "Uladzislau Rezki (Sony)" Date: Fri, 8 Mar 2024 18:34:07 +0100 Subject: rcu: Support direct wake-up of synchronize_rcu() users This patch introduces a small enhancement which allows to do a direct wake-up of synchronize_rcu() callers. It occurs after a completion of grace period, thus by the gp-kthread. Number of clients is limited by the hard-coded maximum allowed threshold. The remaining part, if still exists is deferred to a main worker. Link: https://lore.kernel.org/lkml/Zd0ZtNu+Rt0qXkfS@lothringen/ Reviewed-by: Paul E. McKenney Signed-off-by: Uladzislau Rezki (Sony) --- kernel/rcu/tree.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'kernel/rcu/tree.h') diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index b942b9437438..2832787cee1d 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -315,6 +315,12 @@ do { \ __set_current_state(TASK_RUNNING); \ } while (0) +/* + * A max threshold for synchronize_rcu() users which are + * awaken directly by the rcu_gp_kthread(). Left part is + * deferred to the main worker. + */ +#define SR_MAX_USERS_WAKE_FROM_GP 5 #define SR_NORMAL_GP_WAIT_HEAD_MAX 5 struct sr_wait_node { -- cgit v1.2.3