[PATCH 0/8] rcu: Fix expedited GP deadlock (and cleanup some nocb stuff)

Frederic Weisbecker
2023-12-08T22:05:52Z

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.

Frederic Weisbecker (8):
rcu/nocb: Make IRQs disablement symetric
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 | 12 +--
kernel/rcu/tree_exp.h | 81 +++-----------
kernel/rcu/tree_nocb.h | 38 ++++---
kernel/rcu/tree_plugin.h | 52 ++-------
6 files changed, 191 insertions(+), 219 deletions(-)

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2.42.1