Frederic Weisbecker 20377f32dc rcu: Stop chasing QS if another CPU did it for us ... When a CPU is idle and others CPUs handled its extended quiescent state to complete grace periods on its behalf, it will catch up with completed grace periods numbers when it wakes up. But at this point there might be no more grace period to complete, but still the woken CPU always keeps its stale qs_pending value and will then continue to chase quiescent states even if its not needed anymore. This results in clusters of spurious softirqs until a new real grace period is started. Because if we continue to chase quiescent states but we have completed every grace periods, rcu_report_qs_rdp() is puzzled and makes that state run into infinite loops. As suggested by Lai Jiangshan, just reset qs_pending if someone completed every grace periods on our behalf. Suggested-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>		2010-12-17 12:34:18 -08:00
..
debug	Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-09-08 11:13:42 -07:00
gcov	gcov: fix null-pointer dereference for certain module types	2010-09-09 18:57:23 -07:00
irq
power	Merge branch 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6	2010-09-11 15:50:53 -07:00
time	time: Workaround gcc loop optimization that causes 64bit div errors	2010-08-13 12:03:24 -07:00
trace	Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-09-10 07:31:24 -07:00
.gitignore
acct.c	pass a struct path to vfs_statfs	2010-08-09 16:48:42 -04:00
async.c
audit_tree.c
audit_watch.c	Revert "fsnotify: store struct file not struct path"	2010-08-12 14:23:04 -07:00
audit.c	Merge branch 'for-linus' of git://git.infradead.org/users/eparis/notify	2010-08-10 11:39:13 -07:00
audit.h
auditfilter.c
auditsc.c	vfs: add helpers to get root and pwd	2010-08-11 00:28:20 -04:00
backtracetest.c
bounds.c
capability.c
cgroup_freezer.c
cgroup.c	Merge branch 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu into core/rcu	2010-10-07 09:43:11 +02:00
compat.c	compat: Make compat_alloc_user_space() incorporate the access_ok()	2010-09-14 16:08:45 -07:00
configs.c
cpu.c
cpuset.c	Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2010-08-06 09:39:22 -07:00
cred.c	Add a dummy printk function for the maintenance of unused printks	2010-08-12 09:51:35 -07:00
delayacct.c
dma.c
early_res.c
elfcore.c
exec_domain.c	sys_personality: remove the bogus checks in sys_personality()->__set_personality() path	2010-08-09 20:45:05 -07:00
exit.c	Fix unprotected access to task credentials in waitid()	2010-08-17 18:07:43 -07:00
extable.c
fork.c	rmap: fix walk during fork	2010-09-22 17:22:39 -07:00
freezer.c
futex_compat.c
futex.c
groups.c	kernel/groups.c: fix integer overflow in groups_search	2010-09-09 18:57:24 -07:00
hrtimer.c	gcc-4.6: kernel/*: Fix unused but set warnings	2010-09-05 14:36:58 +02:00
hung_task.c
hw_breakpoint.c	hw breakpoints: Fix pid namespace bug	2010-09-17 04:42:59 +02:00
itimer.c
kallsyms.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c	kexec: return -EFAULT on copy_to_user() failures	2010-08-11 08:59:22 -07:00
kfifo.c	kfifo: fix scatterlist usage	2010-10-01 10:50:58 -07:00
kmod.c	Make do_execve() take a const filename pointer	2010-08-17 18:07:43 -07:00
kprobes.c
ksysfs.c
kthread.c
latencytop.c
lockdep_internals.h
lockdep_proc.c
lockdep_states.h
lockdep.c
Makefile	rcu: Add a TINY_PREEMPT_RCU	2010-08-20 08:55:00 -07:00
module.c	modules: Fix module_bug_list list corruption race	2010-10-05 11:29:27 -07:00
mutex-debug.c
mutex-debug.h
mutex.c	mutex: Fix annotations to include it in kernel-locking docbook	2010-09-03 08:19:51 +02:00
mutex.h
notifier.c
ns_cgroup.c
nsproxy.c
padata.c
panic.c	lib/bug.c: add oops end marker to WARN implementation	2010-08-11 08:59:22 -07:00
params.c	param: locking for kernel parameters	2010-08-11 23:04:20 +09:30
perf_event.c	perf: Fix CPU hotplug	2010-09-09 20:38:52 +02:00
pid_namespace.c
pid.c	Add RCU check for find_task_by_vpid().	2010-08-19 17:18:02 -07:00
pm_qos_params.c	PM QoS: Correct pr_debug() misuse and improve parameter checks	2010-09-11 00:53:05 +02:00
posix-cpu-timers.c	Merge branch 'writable_limits' of git://decibel.fi.muni.cz/~xslaby/linux	2010-08-10 12:07:51 -07:00
posix-timers.c
printk.c	gcc-4.6: printk: use stable variable to dump kmsg buffer	2010-08-09 20:45:06 -07:00
profile.c
ptrace.c	ptrace: optimize exit_ptrace() for the likely case	2010-08-11 08:59:19 -07:00
range.c	kernel/range: remove unused definition of ARRAY_SIZE()	2010-08-09 20:45:06 -07:00
rcupdate.c	Merge branch 'rcu/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu into core/rcu	2010-10-07 09:43:11 +02:00
rcutiny_plugin.h	rcu: Distinguish between boosting and boosted	2010-11-29 22:01:56 -08:00
rcutiny.c	rcu: add tracing for TINY_RCU and TINY_PREEMPT_RCU	2010-11-29 22:01:55 -08:00
rcutorture.c	rcu: add priority-inversion testing to rcutorture	2010-10-07 10:41:08 -07:00
rcutree_plugin.h	rcu: increase synchronize_sched_expedited() batching	2010-12-17 12:34:08 -08:00
rcutree_trace.c	rcu,cleanup: simplify the code when cpu is dying	2010-11-29 22:01:58 -08:00
rcutree.c	rcu: Stop chasing QS if another CPU did it for us	2010-12-17 12:34:18 -08:00
rcutree.h	rcu,cleanup: simplify the code when cpu is dying	2010-11-29 22:01:58 -08:00
relay.c
res_counter.c
resource.c
rtmutex_common.h
rtmutex-debug.c
rtmutex-debug.h
rtmutex-tester.c
rtmutex.c
rtmutex.h
rwsem.c
sched_clock.c
sched_cpupri.c
sched_cpupri.h
sched_debug.c
sched_fair.c	sched: suppress RCU lockdep splat in task_fork_fair	2010-10-07 10:40:50 -07:00
sched_features.h
sched_idletask.c
sched_rt.c
sched_stats.h
sched.c	rcu,cleanup: move synchronize_sched_expedited() out of sched.c	2010-11-29 22:01:58 -08:00
seccomp.c
semaphore.c
signal.c
smp.c	generic-ipi: Fix deadlock in __smp_call_function_single	2010-09-10 16:48:40 +02:00
softirq.c
spinlock.c
srcu.c	rcu: Make synchronize_srcu_expedited() fast if running readers	2010-11-29 22:02:40 -08:00
stacktrace.c
stop_machine.c	stop_machine: struct cpu_stopper, remove alignment padding on 64 bits	2010-08-09 20:45:06 -07:00
sys_ni.c
sys.c	pid: make setpgid() system call use RCU read-side critical section	2010-08-31 17:00:18 -07:00
sysctl_binary.c
sysctl_check.c
sysctl.c	gcc-4.6: kernel/*: Fix unused but set warnings	2010-09-05 14:36:58 +02:00
taskstats.c
test_kprobes.c
time.c
timeconst.pl
timer.c	kernel/timer.c: fix kernel-doc function parameter warning	2010-08-10 15:33:09 -07:00
tracepoint.c
tsacct.c
uid16.c
up.c
user_namespace.c
user-return-notifier.c
user.c
utsname_sysctl.c
utsname.c
wait.c
watchdog.c	lockup_detector: Sync touch_*_watchdog back to old semantics	2010-09-01 10:02:28 +02:00
workqueue_sched.h
workqueue.c	workqueue: add documentation	2010-09-13 10:26:52 +02:00