[PATCH 00/11] rcu: Make rcu_core() safe in PREEMPT_RT with NOCB + a few other fixes v2

Frederic Weisbecker
2021-10-11T14:51:55Z

Hi,

No code change in this v2, only changelogs:

* Add tags from Valentin and Sebastian

* Remove last reference to SEGCBLIST_SOFTIRQ_ONLY (thanks Valentin)

* Rewrite changelog for "rcu/nocb: Check a stable offloaded state to manipulate qlen_last_fqs_check"
after off-list debates with Paul.

* Remove the scenario with softirq interrupting rcuc on
"rcu/nocb: Limit number of softirq callbacks only on softirq" as it's
probably not possible (thanks Valentin).

* Remove the scenario with task spent scheduling out accounted on tlimit
as it's not possible (thanks Valentin)
(see "rcu: Apply callbacks processing time limit only on softirq")

* Fixed changelog of
"rcu/nocb: Don't invoke local rcu core on callback overload from nocb kthread"
(thanks Sebastian).

git://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
rcu/rt-v2

HEAD: 2c9349986d5f70a555195139665841cd98e9aba4

Thanks,
Frederic
---

Frederic Weisbecker (10):
rcu/nocb: Make local rcu_nocb_lock_irqsave() safe against concurrent deoffloading
rcu/nocb: Prepare state machine for a new step
rcu/nocb: Invoke rcu_core() at the start of deoffloading
rcu/nocb: Make rcu_core() callbacks acceleration (de-)offloading safe
rcu/nocb: Check a stable offloaded state to manipulate qlen_last_fqs_check
rcu/nocb: Use appropriate rcu_nocb_lock_irqsave()
rcu/nocb: Limit number of softirq callbacks only on softirq
rcu: Fix callbacks processing time limit retaining cond_resched()
rcu: Apply callbacks processing time limit only on softirq
rcu/nocb: Don't invoke local rcu core on callback overload from nocb kthread

Thomas Gleixner (1):
rcu/nocb: Make rcu_core() callbacks acceleration preempt-safe

include/linux/rcu_segcblist.h | 51 ++++++++++++++++++-------
kernel/rcu/rcu_segcblist.c | 10 ++---
kernel/rcu/rcu_segcblist.h | 12 +++---
kernel/rcu/tree.c | 87 +++++++++++++++++++++++++++++--------------
kernel/rcu/tree.h | 16 +++++---
kernel/rcu/tree_nocb.h | 29 ++++++++++++---
6 files changed, 141 insertions(+), 64 deletions(-)