linux-yocto/kernel/rcu
Paul E. McKenney 1dd01c0650 rcu: Summarize RCU CPU stall warnings during CSD-lock stalls
During CSD-lock stalls, the additional information output by RCU CPU
stall warnings is usually redundant, flooding the console for not good
reason.  However, this has been the way things work for a few years.
This commit therefore adds an rcutree.csd_lock_suppress_rcu_stall kernel
boot parameter that causes RCU CPU stall warnings to be abbreviated to
a single line when there is at least one CPU that has been stuck waiting
for CSD lock for more than five seconds.

To make this abbreviated message happen with decent probability:

tools/testing/selftests/rcutorture/bin/kvm.sh --allcpus --duration 8 \
	--configs "2*TREE01" --kconfig "CONFIG_CSD_LOCK_WAIT_DEBUG=y" \
	--bootargs "csdlock_debug=1 rcutorture.stall_cpu=200 \
	rcutorture.stall_cpu_holdoff=120 rcutorture.stall_cpu_irqsoff=1 \
	rcutree.csd_lock_suppress_rcu_stall=1 \
	rcupdate.rcu_exp_cpu_stall_timeout=5000" --trust-make

[ paulmck: Apply kernel test robot feedback. ]

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay <neeraj.upadhyay@kernel.org>
2024-08-15 00:10:50 +05:30
..
Kconfig rcu: Create NEED_TASKS_RCU to factor out enablement logic 2024-04-15 11:29:48 +02:00
Kconfig.debug rcu: Restrict access to RCU CPU stall notifiers 2023-12-12 02:31:22 +05:30
Makefile rcuperf: Change rcuperf to rcuscale 2020-08-24 18:39:24 -07:00
rcu_segcblist.c rcu: Use rcu_segcblist_segempty() instead of open coding it 2023-10-04 17:33:18 +02:00
rcu_segcblist.h rcu: Throttle callback invocation based on number of ready callbacks 2023-01-03 17:28:34 -08:00
rcu.h rcutorture: Make rcutorture support print rcu-tasks gp state 2024-04-16 11:16:35 +02:00
rcuscale.c rcutorture: Add missing MODULE_DESCRIPTION() macros 2024-06-06 11:44:42 -07:00
rcutorture.c rcutorture: Add missing MODULE_DESCRIPTION() macros 2024-06-06 11:44:42 -07:00
refscale.c rcutorture: Add missing MODULE_DESCRIPTION() macros 2024-06-06 11:44:42 -07:00
srcutiny.c srcu: Fill out polled grace-period APIs 2024-06-18 10:13:37 -07:00
srcutree.c Merge branches 'doc.2024.06.06a', 'fixes.2024.07.04a', 'mb.2024.06.28a', 'nocb.2024.06.03a', 'rcu-tasks.2024.06.06a', 'rcutorture.2024.06.06a' and 'srcu.2024.06.18a' into HEAD 2024-07-04 13:54:17 -07:00
sync.c rcu: Eliminate lockless accesses to rcu_sync->gp_count 2024-07-04 13:48:57 -07:00
tasks.h rcu/tasks: Fix stale task snaphot for Tasks Trace 2024-06-06 11:50:04 -07:00
tiny.c rcu: Make Tiny RCU explicitly disable preemption 2024-04-15 11:29:48 +02:00
tree_exp.h rcu/exp: Remove redundant full memory barrier at the end of GP 2024-06-28 06:44:12 -07:00
tree_nocb.h rcu/nocb: Remove buggy bypass lock contention mitigation 2024-06-03 17:29:15 -07:00
tree_plugin.h Merge branches 'doc.2024.06.06a', 'fixes.2024.07.04a', 'mb.2024.06.28a', 'nocb.2024.06.03a', 'rcu-tasks.2024.06.06a', 'rcutorture.2024.06.06a' and 'srcu.2024.06.18a' into HEAD 2024-07-04 13:54:17 -07:00
tree_stall.h rcu: Summarize RCU CPU stall warnings during CSD-lock stalls 2024-08-15 00:10:50 +05:30
tree.c Merge branches 'doc.2024.06.06a', 'fixes.2024.07.04a', 'mb.2024.06.28a', 'nocb.2024.06.03a', 'rcu-tasks.2024.06.06a', 'rcutorture.2024.06.06a' and 'srcu.2024.06.18a' into HEAD 2024-07-04 13:54:17 -07:00
tree.h Merge branches 'doc.2024.06.06a', 'fixes.2024.07.04a', 'mb.2024.06.28a', 'nocb.2024.06.03a', 'rcu-tasks.2024.06.06a', 'rcutorture.2024.06.06a' and 'srcu.2024.06.18a' into HEAD 2024-07-04 13:54:17 -07:00
update.c rcu-tasks: Make Tasks RCU wait idly for grace-period delays 2024-04-09 15:11:49 +02:00