linux/kernel/rcu
Paul E. McKenney 5fe0a56298 rcu: Make rcu_gp_kthread() check for early-boot activity
The rcu_gp_kthread() function immediately sleeps waiting to be notified
of the need for a new grace period, which currently works because there
are a number of code sequences that will provide the needed wakeup later.
However, some of these code sequences need to acquire the root rcu_node
structure's ->lock, and contention on that lock has started manifesting.
This commit therefore makes rcu_gp_kthread() check for early-boot activity
when it starts up, omitting the initial sleep in that case.

Reported-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:29:24 -07:00
..
Kconfig rcu: Drive TASKS_RCU directly off of PREEMPT 2017-08-17 07:26:04 -07:00
Kconfig.debug rcu: Move RCU debug Kconfig options to kernel/rcu 2017-06-08 18:52:44 -07:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rcu_segcblist.c rcu/segcblist: Include rcupdate.h 2017-10-19 12:13:36 -07:00
rcu_segcblist.h rcu: Remove unused RCU list functions 2017-07-25 13:04:49 -07:00
rcu.h rcu: Create RCU-specific workqueues with rescuers 2018-02-23 15:14:40 -08:00
rcuperf.c torture: Provide more sensible nreader/nwriter defaults for rcuperf 2018-02-20 16:22:01 -08:00
rcutorture.c rcutorture: Record which grace-period primitives are tested 2018-02-20 16:21:58 -08:00
srcutiny.c srcu: Move rcu_scheduler_starting() from Tiny RCU to Tiny SRCU 2017-07-24 16:03:22 -07:00
srcutree.c Merge branches 'fixes.2018.02.23a', 'srcu.2018.02.20a' and 'torture.2018.02.20a' into HEAD 2018-02-23 15:15:41 -08:00
sync.c doc: Fix various RCU docbook comment-header problems 2017-10-19 22:26:11 -04:00
tiny.c srcu: Move rcu_scheduler_starting() from Tiny RCU to Tiny SRCU 2017-07-24 16:03:22 -07:00
tree_exp.h rcu: Create RCU-specific workqueues with rescuers 2018-02-23 15:14:40 -08:00
tree_plugin.h rcu: Add accessor macros for the ->need_future_gp[] array 2018-05-15 10:29:18 -07:00
tree.c rcu: Make rcu_gp_kthread() check for early-boot activity 2018-05-15 10:29:24 -07:00
tree.h rcu: Add accessor macros for the ->need_future_gp[] array 2018-05-15 10:29:18 -07:00
update.c rcu: Export init_rcu_head() and destroy_rcu_head() to GPL modules 2017-12-07 19:51:49 -05:00