Commit ed336c6f authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

doc: Call out queue_rcu_work() for blocking RCU callbacks 



The current checklist.rst file correctly notes that RCU callbacks execute
in BH context, and cannot block.  This commit adds words advising people
needing callbacks to block to use workqueues, for example, by replacing
call_rcu() with queue_rcu_work().

Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent 4d2f862b

Documentation/RCU/checklist.rst

+3 −0
Original line number Diff line number Diff line
@@ -190,6 +190,9 @@ over a rather long period of time, but improvements are always welcome! 


5.	If call_rcu() or call_srcu() is used, the callback function will

	be called from softirq context.  In particular, it cannot block.

	If you need the callback to block, run that code in a workqueue

	handler scheduled from the callback.  The queue_rcu_work()

	function does this for you in the case of call_rcu().



6.	Since synchronize_rcu() can block, it cannot be called

	from any sort of irq context.  The same rule applies