Paul E. McKenney ab21f6081f rcutorture: Give the scheduler a chance on PREEMPT && NO_HZ_FULL kernels ... In !PREEMPT kernels, cond_resched() is a no-op. In NO_HZ_FULL kernels, in-kernel execution (such as that of rcutorture's kthreads) might extend indefinitely without the scheduler gaining the aid of a scheduling-clock interrupt. This combination can make the interaction of an rcutorture forward-progress test and a CPU-hotplug stop_machine operation make less forward progress than one might like. Additionally, Sebastian Siewior notes that NO_HZ_FULL kernels have a scheduler check upon return to userspace execution, which suggests that in-kernel emulation of tight userspace loops containing system calls doing call_rcu() might also need explicit checks in the PREEMPT && NO_HZ_FULL case. This commit therefore introduces a rcu_torture_fwd_prog_cond_resched() function that explicitly invokes schedule() in such kernels whenever need_resched() returns true, while retaining use of cond_resched() for kernels that are either !PREEMPT or !NO_HZ_FULL. Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>		2019-05-28 09:06:09 -07:00
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Kconfig
Kconfig.debug
Makefile
rcu_segcblist.c
rcu_segcblist.h
rcu.h
rcuperf.c
rcutorture.c	rcutorture: Give the scheduler a chance on PREEMPT && NO_HZ_FULL kernels	2019-05-28 09:06:09 -07:00
srcutiny.c
srcutree.c
sync.c
tiny.c
tree_exp.h
tree_plugin.h
tree_stall.h
tree.c
tree.h
update.c