[0/12] Polled grace-period updates for v5.20

Message

Paul E. McKenney June 20, 2022, 10:49 p.m. UTC

Hello!

This series adds support for polled expedited RCU grace periods:

1.	Make normal polling GP be more precise about sequence numbers.

2.	Provide a get_completed_synchronize_rcu() function.

3.	Validate get_completed_synchronize_rcu().

4.	Switch polled grace-period APIs to ->gp_seq_polled.

5.	Make polled grace-period API account for expedited grace periods.

6.	Make Tiny RCU grace periods visible to polled APIs.

7.	Verify that polled GP API sees synchronous grace periods.

8.	Add polled expedited grace-period primitives.

9.	Test polled expedited grace-period primitives.

10.	Put panic_on_rcu_stall() after expedited RCU CPU stall warnings,
	courtesy of Zqiang.

11.	Diagnose extended sync_rcu_do_polled_gp() loops.

12.	Add irqs-disabled indicator to expedited RCU CPU stall warnings,
	courtesy of Zqiang.

						Thanx, Paul

------------------------------------------------------------------------

 b/include/linux/rcupdate.h |    1 
 b/include/linux/rcutiny.h  |   10 +++
 b/include/linux/rcutree.h  |    2 
 b/kernel/rcu/rcu.h         |   12 ++++
 b/kernel/rcu/rcutorture.c  |    6 ++
 b/kernel/rcu/tiny.c        |    4 -
 b/kernel/rcu/tree.c        |    4 -
 b/kernel/rcu/tree.h        |    2 
 b/kernel/rcu/tree_exp.h    |   16 +++++-
 b/kernel/rcu/update.c      |   13 ++++
 kernel/rcu/rcu.h           |    3 +
 kernel/rcu/rcutorture.c    |   97 +++++++++++++++++++++++++++++++-----
 kernel/rcu/tiny.c          |    7 +-
 kernel/rcu/tree.c          |  119 ++++++++++++++++++++++++++++++++++++++++-----
 kernel/rcu/tree.h          |    8 +++
 kernel/rcu/tree_exp.h      |   99 +++++++++++++++++++++++++++++++++++--
 16 files changed, 365 insertions(+), 38 deletions(-)