TREE04 can trigger a writer stall if run with memory pressure. This
is due to a circular dependency between waiting for expedited grace
period and polling on expedited grace period when workqueues go back
to mayday serialization.
Here is a proposal fix.
Changes since v1:
* Add __maybe_unused to __call_rcu_nocb_wake() declaration (reported by Paul)
* Add reviewed-by tags
* Fix nocb changelog (reported by Neeraj)
* Fixed comment (reported by Hillf)
Frederic Weisbecker (8):
rcu/nocb: Make IRQs disablement symmetric
rcu/nocb: Re-arrange call_rcu() NOCB specific code
rcu/exp: Fix RCU expedited parallel grace period kworker allocation
failure recovery
rcu/exp: Handle RCU expedited grace period kworker allocation failure
rcu: s/boost_kthread_mutex/kthread_mutex
rcu/exp: Make parallel exp gp kworker per rcu node
rcu/exp: Handle parallel exp gp kworkers affinity
rcu/exp: Remove rcu_par_gp_wq
kernel/rcu/rcu.h | 5 -
kernel/rcu/tree.c | 222 +++++++++++++++++++++++++--------------
kernel/rcu/tree.h | 18 ++--
kernel/rcu/tree_exp.h | 81 +++-----------
kernel/rcu/tree_nocb.h | 38 ++++---
kernel/rcu/tree_plugin.h | 52 ++-------
6 files changed, 194 insertions(+), 222 deletions(-)
--
2.34.1
