From 84c8157d0602f10388a99854c88d5d5b41829230 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 16 May 2023 03:41:37 -0700 Subject: [PATCH] UPSTREAM: rcu: Update synchronize_rcu_mult() comment for call_rcu_hurry() Those who have worked with RCU for some time will naturally think in terms of the long-standing call_rcu() API rather than the much newer call_rcu_hurry() API. But it is call_rcu_hurry() that you should normally pass to synchronize_rcu_mult(). This commit therefore updates the header comment to point this out. Signed-off-by: Paul E. McKenney Reviewed-by: Joel Fernandes (Google) (cherry picked from commit 6716f4d39c17febf7aa4fa5f5923da67a8d10e85) Bug: 258241771 Signed-off-by: Joel Fernandes Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/4909037 Reviewed-by: Ross Zwisler Reviewed-by: Sean Paul Reviewed-by: Vineeth Pillai Signed-off-by: Qais Yousef Change-Id: I0d701825ddd7e15cebd92190388fbf78c04d26fb --- include/linux/rcupdate_wait.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/include/linux/rcupdate_wait.h b/include/linux/rcupdate_wait.h index 699b938358bf..5e0f74f2f8ca 100644 --- a/include/linux/rcupdate_wait.h +++ b/include/linux/rcupdate_wait.h @@ -42,6 +42,11 @@ do { \ * call_srcu() function, with this wrapper supplying the pointer to the * corresponding srcu_struct. * + * Note that call_rcu_hurry() should be used instead of call_rcu() + * because in kernels built with CONFIG_RCU_LAZY=y the delay between the + * invocation of call_rcu() and that of the corresponding RCU callback + * can be multiple seconds. + * * The first argument tells Tiny RCU's _wait_rcu_gp() not to * bother waiting for RCU. The reason for this is because anywhere * synchronize_rcu_mult() can be called is automatically already a full