Repository files (latest commit first)

Filename	Latest commit message	Latest commit date
Frederic Weisbecker 337bba09d8 rcu/nocb: Perform deferred wake up before last idle's need_resched() check ... commit 43789ef3f7d61aa7bed0cb2764e588fc990c30ef upstream. Entering RCU idle mode may cause a deferred wake up of an RCU NOCB_GP kthread (rcuog) to be serviced. Usually a local wake up happening while running the idle task is handled in one of the need_resched() checks carefully placed within the idle loop that can break to the scheduler. Unfortunately the call to rcu_idle_enter() is already beyond the last generic need_resched() check and we may halt the CPU with a resched request unhandled, leaving the task hanging. Fix this with splitting the rcuog wakeup handling from rcu_idle_enter() and place it before the last generic need_resched() check in the idle loop. It is then assumed that no call to call_rcu() will be performed after that in the idle loop until the CPU is put in low power mode. Fixes: 96d3fd0d31 (rcu: Break call_rcu() deadlock involving scheduler and perf) Reported-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20210131230548.32970-3-frederic@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-03-04 10:26:47 +01:00
..
Kconfig
Kconfig.debug
Makefile
rcu.h
rcu_segcblist.c
rcu_segcblist.h
rcuperf.c
rcutorture.c
srcutiny.c
srcutree.c	srcu: Apply *_ONCE() to ->srcu_last_gp_end	2020-02-11 04:35:08 -08:00
sync.c
tiny.c
tree.c	rcu/nocb: Perform deferred wake up before last idle's need_resched() check	2021-03-04 10:26:47 +01:00
tree.h
tree_exp.h	rcu: Allow only one expedited GP to run concurrently with wakeups	2020-03-05 16:43:50 +01:00
tree_plugin.h	rcu/nocb: Perform deferred wake up before last idle's need_resched() check	2021-03-04 10:26:47 +01:00
tree_stall.h
update.c