[PATCH tip/core/rcu 0/4] Fix RCU priority boosting

From: Paul E. McKenney
Date: Tue Jan 19 2021 - 23:32:45 EST


This series fixes a bug in which an RCU-priority-boosted task can stay
boosted for some time after it has exited its RCU read-side critical
section. This bug arose during the RCU flavor consolidation effort.
The patches are as follows:

1. Expedite deboost in case of deferred quiescent state.

2. Make TREE03 use real-time tree.use_softirq setting.

3. Run rcuo kthreads at elevated priority in CONFIG_RCU_BOOST

4. Fix testing of RCU priority boosting.

Thanx, Paul


kernel/rcu/rcutorture.c | 36 +++++++------
kernel/rcu/tree_plugin.h | 28 +++++-----
tools/testing/selftests/rcutorture/configs/rcu/TREE03.boot | 1
3 files changed, 39 insertions(+), 26 deletions(-)