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 v2 (no functional changes, just renames and reorganization):
_ Move nocb cleanups to their own series
_ Rename can_queue parameter to use_worker [2/7]
_ Better explain the rename of the mutex [3/7]
_ New commit with just code move to ease review [4/7]
_ Comment declaration of the new rnp->exp_worker field [5/7]
Thanks.
Frederic Weisbecker (7):
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: Move expedited kthread worker creation functions above
rcutree_prepare_cpu()
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 | 175 +++++++++++++++++++++++++++------------
kernel/rcu/tree.h | 11 ++-
kernel/rcu/tree_exp.h | 78 +++--------------
kernel/rcu/tree_plugin.h | 52 ++----------
5 files changed, 142 insertions(+), 179 deletions(-)
--
2.34.1
