[PATCH tip/core/rcu 2/8] doc: Remove obsolete RCU-bh and RCU-sched update-side API members

From: paulmck
Date: Tue Jan 05 2021 - 19:55:20 EST


From: "Paul E. McKenney" <paulmck@xxxxxxxxxx>

synchronize_rcu_bh(), synchronize_rcu_bh_expedited(), call_rcu_bh(),
rcu_barrier_bh(), synchronize_sched(), synchronize_rcu_sched_expedited(),
call_rcu_sched(), and rcu_barrier_sched() no longer exist, so this
commit removes mention of them.

Reported-by: Joel Fernandes <joel@xxxxxxxxxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
.../RCU/Design/Requirements/Requirements.rst | 28 +++++++++++-----------
1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/Documentation/RCU/Design/Requirements/Requirements.rst b/Documentation/RCU/Design/Requirements/Requirements.rst
index 9b23be6..1e3df77 100644
--- a/Documentation/RCU/Design/Requirements/Requirements.rst
+++ b/Documentation/RCU/Design/Requirements/Requirements.rst
@@ -2438,13 +2438,13 @@ glance as if rcu_read_unlock_bh() was executing very slowly.

The `RCU-bh
API <https://lwn.net/Articles/609973/#RCU%20Per-Flavor%20API%20Table>`__
-includes rcu_read_lock_bh(), rcu_read_unlock_bh(),
-rcu_dereference_bh(), rcu_dereference_bh_check(),
-synchronize_rcu_bh(), synchronize_rcu_bh_expedited(),
-call_rcu_bh(), rcu_barrier_bh(), and
-rcu_read_lock_bh_held(). However, the update-side APIs are now
-simple wrappers for other RCU flavors, namely RCU-sched in
-CONFIG_PREEMPT=n kernels and RCU-preempt otherwise.
+includes rcu_read_lock_bh(), rcu_read_unlock_bh(), rcu_dereference_bh(),
+rcu_dereference_bh_check(), and rcu_read_lock_bh_held(). However, the
+old RCU-bh update-side APIs are now gone, replaced by synchronize_rcu(),
+synchronize_rcu_expedited(), call_rcu(), and rcu_barrier(). In addition,
+anything that disables bottom halves also marks an RCU-bh read-side
+critical section, including local_bh_disable() and local_bh_enable(),
+local_irq_save() and local_irq_restore(), and so on.

Sched Flavor (Historical)
~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -2481,13 +2481,13 @@ The `RCU-sched
API <https://lwn.net/Articles/609973/#RCU%20Per-Flavor%20API%20Table>`__
includes rcu_read_lock_sched(), rcu_read_unlock_sched(),
rcu_read_lock_sched_notrace(), rcu_read_unlock_sched_notrace(),
-rcu_dereference_sched(), rcu_dereference_sched_check(),
-synchronize_sched(), synchronize_rcu_sched_expedited(),
-call_rcu_sched(), rcu_barrier_sched(), and
-rcu_read_lock_sched_held(). However, anything that disables
-preemption also marks an RCU-sched read-side critical section, including
-preempt_disable() and preempt_enable(), local_irq_save() and
-local_irq_restore(), and so on.
+rcu_dereference_sched(), rcu_dereference_sched_check(), and
+rcu_read_lock_sched_held(). However, the old RCU-sched update-side APIs
+are now gone, replaced by synchronize_rcu(), synchronize_rcu_expedited(),
+call_rcu(), and rcu_barrier(). In addition, anything that disables
+preemption also marks an RCU-sched read-side critical section,
+including preempt_disable() and preempt_enable(), local_irq_save()
+and local_irq_restore(), and so on.

Sleepable RCU
~~~~~~~~~~~~~
--
2.9.5