OpenCloudOS-Kernel/kernel
Paul E. McKenney d09b62dfa3 rcu: Fix synchronization for rcu_process_gp_end() uses of ->completed counter
Impose a clear locking design on the rcu_process_gp_end()
function's use of the ->completed counter.  This is done by
creating a ->completed field in the rcu_node structure, which
can safely be accessed under the protection of that structure's
lock.  Performance and scalability are maintained by using a
form of double-checked locking, so that rcu_process_gp_end()
only acquires the leaf rcu_node structure's ->lock if a grace
period has recently ended.

This fix reduces rcutorture failure rate by at least two orders
of magnitude under heavy stress with force_quiescent_state()
being invoked artificially often.  Without this fix,
unsynchronized access to the ->completed field can cause
rcu_process_gp_end() to advance callbacks whose grace period has
not yet expired.  (Bad idea!)

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: mathieu.desnoyers@polymtl.ca
Cc: josh@joshtriplett.org
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
Cc: Valdis.Kletnieks@vt.edu
Cc: dhowells@redhat.com
Cc: <stable@kernel.org> # .32.x
LKML-Reference: <12571987494069-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-11-10 04:11:54 +01:00
..
gcov microblaze: Enable GCOV_PROFILE_ALL 2009-09-21 14:29:21 +02:00
irq Merge branch 'irq-threaded-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-09-11 13:21:31 -07:00
power headers: utsname.h redux 2009-09-23 18:13:10 -07:00
time NOHZ: update idle state also when NOHZ is inactive 2009-10-07 13:05:05 +02:00
trace Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-10-08 12:06:09 -07:00
.gitignore
Kconfig.freezer
Kconfig.hz
Kconfig.preempt
Makefile rcu: "Tiny RCU", The Bloatwatch Edition 2009-10-26 09:40:29 +01:00
acct.c bsdacct: switch credentials for writing to the accounting file 2009-08-24 11:33:40 +10:00
async.c async: Fix lack of boot-time console due to insufficient synchronization 2009-06-08 12:31:53 -07:00
audit.c Audit: send signal info if selinux is disabled 2009-09-24 03:50:26 -04:00
audit.h Fix rule eviction order for AUDIT_DIR 2009-06-24 00:02:38 -04:00
audit_tree.c Fix rule eviction order for AUDIT_DIR 2009-06-24 00:02:38 -04:00
audit_watch.c Audit: reorganize struct audit_watch to save 8 bytes 2009-09-24 03:50:25 -04:00
auditfilter.c Audit: clean up all op= output to include string quoting 2009-06-24 00:00:52 -04:00
auditsc.c Audit: rearrange audit_context to save 16 bytes per struct 2009-09-24 03:50:26 -04:00
backtracetest.c
bounds.c
capability.c
cgroup.c cgroup: catch bad css refcnt at css_put 2009-10-01 16:11:12 -07:00
cgroup_freezer.c cgroups: let ss->can_attach and ss->attach do whole threadgroups at a time 2009-09-24 07:20:58 -07:00
compat.c signals: implement sys_rt_tgsigqueueinfo 2009-04-30 19:24:24 +02:00
configs.c
cpu.c Merge branch 'x86-pat-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-09-15 09:19:38 -07:00
cpuset.c cgroups: let ss->can_attach and ss->attach do whole threadgroups at a time 2009-09-24 07:20:58 -07:00
cred-internals.h
cred.c creds_are_invalid() needs to be exported for use by modules: 2009-09-23 11:02:26 -07:00
delayacct.c headers: taskstats_kern.h trim 2009-09-18 09:48:52 -07:00
dma.c
exec_domain.c Get rid of indirect include of fs_struct.h 2009-03-31 23:00:27 -04:00
exit.c Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-10-08 12:16:35 -07:00
extable.c Merge branch 'tracing-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-04-05 11:04:19 -07:00
fork.c Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-10-08 12:16:35 -07:00
freezer.c sched: fix nr_uninterruptible accounting of frozen tasks really 2009-07-18 14:19:53 +02:00
futex.c futex: Fix spurious wakeup for requeue_pi really 2009-10-28 20:34:34 +01:00
futex_compat.c futex: Fix compat_futex to be same as futex for REQUEUE_PI 2009-08-10 15:41:12 +02:00
groups.c groups: move code to kernel/groups.c 2009-06-16 19:47:48 -07:00
hrtimer.c Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-10-05 12:04:16 -07:00
hung_task.c sysctl: remove "struct file *" argument of ->proc_handler 2009-09-24 07:21:04 -07:00
itimer.c itimers: Add tracepoints for itimer 2009-08-29 14:10:07 +02:00
kallsyms.c kallsyms: use new arch_is_kernel_text() 2009-09-23 07:39:30 -07:00
kexec.c kexec: fix omitting offset in extended crashkernel syntax 2009-07-29 19:10:34 -07:00
kfifo.c kfifo: Use "const" definitions 2009-09-19 13:13:17 -07:00
kgdb.c sysrq, intel_fb: fix sysrq g collision 2009-05-15 07:56:24 -05:00
kmod.c Revert "kmod: fix race in usermodehelper code" 2009-09-23 18:12:10 -07:00
kprobes.c const: constify remaining file_operations 2009-10-01 16:11:11 -07:00
ksysfs.c
kthread.c sched: Keep kthreads at default priority 2009-09-09 17:30:06 +02:00
latencytop.c sched, latencytop: incorporate review feedback from Andrew Morton 2009-02-11 10:18:04 +01:00
lockdep.c lockdep: Use cpu_clock() for lockstat 2009-10-09 15:56:44 +02:00
lockdep_internals.h lockdep: BFS cleanup 2009-07-24 10:53:29 +02:00
lockdep_proc.c seq_file: constify seq_operations 2009-09-23 07:39:29 -07:00
lockdep_states.h lockdep: move state bit definitions around 2009-02-14 23:27:59 +01:00
module.c module: fix up CONFIG_KALLSYMS=n build. 2009-10-01 16:11:11 -07:00
mutex-debug.c
mutex-debug.h
mutex.c Merge branch 'linus' into perfcounters/core 2009-06-11 17:55:42 +02:00
mutex.h
notifier.c
ns_cgroup.c cgroups: let ss->can_attach and ss->attach do whole threadgroups at a time 2009-09-24 07:20:58 -07:00
nsproxy.c nsproxy: extract create_nsproxy() 2009-06-18 13:03:56 -07:00
panic.c Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-10-08 12:16:35 -07:00
params.c param: allow whitespace as kernel parameter separator 2009-09-25 00:32:58 +09:30
perf_event.c perf_event: Provide vmalloc() based mmap() backing 2009-10-06 14:21:50 +02:00
pid.c mm: also use alloc_large_system_hash() for the PID hash table 2009-09-22 07:17:38 -07:00
pid_namespace.c pidns: deny CLONE_PARENT|CLONE_NEWPID combination 2009-09-24 07:21:04 -07:00
pm_qos_params.c
posix-cpu-timers.c itimers: Add tracepoints for itimer 2009-08-29 14:10:07 +02:00
posix-timers.c time: Introduce CLOCK_REALTIME_COARSE 2009-08-21 21:43:46 +02:00
printk.c printk: add printk_delay to make messages readable for some scenarios 2009-09-23 07:39:28 -07:00
profile.c kernel/profile.c: Switch /proc/irq/prof_cpu_mask to seq_file 2009-09-20 20:15:40 +02:00
ptrace.c ptrace: __ptrace_detach: do __wake_up_parent() if we reap the tracee 2009-09-24 07:20:59 -07:00
rcupdate.c rcu: "Tiny RCU", The Bloatwatch Edition 2009-10-26 09:40:29 +01:00
rcutiny.c rcu: Do tiny cleanups in rcutiny 2009-10-26 09:40:40 +01:00
rcutorture.c rcu: Improve rcutorture diagnostics when bad torture_type specified 2009-10-26 09:40:31 +01:00
rcutree.c rcu: Fix synchronization for rcu_process_gp_end() uses of ->completed counter 2009-11-10 04:11:54 +01:00
rcutree.h rcu: Fix synchronization for rcu_process_gp_end() uses of ->completed counter 2009-11-10 04:11:54 +01:00
rcutree_plugin.h rcu: Fix TREE_PREEMPT_RCU CPU_HOTPLUG bad-luck hang 2009-10-15 20:33:01 +02:00
rcutree_trace.c rcu: Add rnp->blocked_tasks to tracing 2009-10-15 11:20:22 +02:00
relay.c const: mark struct vm_struct_operations 2009-09-27 11:39:25 -07:00
res_counter.c memcg: some modification to softlimit under hierarchical memory reclaim. 2009-10-01 16:11:13 -07:00
resource.c walk system ram range 2009-09-23 07:39:41 -07:00
rtmutex-debug.c
rtmutex-debug.h
rtmutex-tester.c
rtmutex.c rtmutex: Avoid deadlock in rt_mutex_start_proxy_lock() 2009-08-06 05:50:21 +02:00
rtmutex.h
rtmutex_common.h rt_mutex: add proxy lock routines 2009-04-06 11:14:02 +02:00
rwsem.c
sched.c sched: Set correct normal_prio and prio values in sched_fork() 2009-10-05 13:42:20 +02:00
sched_clock.c sched_clock: Fix atomicity/continuity bug by using cmpxchg64() 2009-09-30 22:56:10 +02:00
sched_cpupri.c sched: Add new prio to cpupri before removing old prio 2009-08-02 14:26:09 +02:00
sched_cpupri.h cpumask: remove cpumask_t from core 2009-03-30 22:05:17 +10:30
sched_debug.c sched: Add new wakeup preemption mode: WAKEUP_RUNNING 2009-09-17 10:17:25 +02:00
sched_fair.c sysctl: remove "struct file *" argument of ->proc_handler 2009-09-24 07:21:04 -07:00
sched_features.h sched: Add new wakeup preemption mode: WAKEUP_RUNNING 2009-09-17 10:17:25 +02:00
sched_idletask.c sched: Simplify sys_sched_rr_get_interval() system call 2009-09-21 09:53:55 +02:00
sched_rt.c sched: Simplify sys_sched_rr_get_interval() system call 2009-09-21 09:53:55 +02:00
sched_stats.h sched: remove unused fields from struct rq 2009-03-24 23:16:51 +01:00
seccomp.c x86-64: seccomp: fix 32/64 syscall hole 2009-03-02 15:41:30 -08:00
semaphore.c
signal.c signals: inline __fatal_signal_pending 2009-09-24 07:21:01 -07:00
slow-work.c sysctl: remove "struct file *" argument of ->proc_handler 2009-09-24 07:21:04 -07:00
smp.c cpumask: remove arch_send_call_function_ipi 2009-09-24 09:34:47 +09:30
softirq.c rcu: Cleanup: balance rcu_irq_enter()/rcu_irq_exit() calls 2009-11-02 16:06:37 +01:00
softlockup.c sysctl: remove "struct file *" argument of ->proc_handler 2009-09-24 07:21:04 -07:00
spinlock.c locking: Allow arch-inlined spinlocks 2009-08-31 18:08:50 +02:00
srcu.c rcu: Add synchronize_srcu_expedited() 2009-10-26 09:40:30 +01:00
stacktrace.c
stop_machine.c cpumask: remove cpumask_t from core 2009-03-30 22:05:17 +10:30
sys.c Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 2009-09-24 07:53:22 -07:00
sys_ni.c Merge branch 'master' of /home/davem/src/GIT/linux-2.6/ 2009-09-24 15:13:11 -07:00
sysctl.c Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 2009-09-24 07:53:22 -07:00
sysctl_check.c
taskstats.c genetlink: make netns aware 2009-07-12 14:03:27 -07:00
test_kprobes.c
time.c time: Prevent 32 bit overflow with set_normalized_timespec() 2009-09-15 10:17:30 +02:00
timeconst.pl
timer.c Merge branch 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-09-23 09:46:15 -07:00
tracepoint.c trivial: fix typo "to to" in multiple files 2009-09-21 15:14:55 +02:00
tsacct.c Fix fixpoint divide exception in acct_update_integrals 2009-03-09 08:13:35 -07:00
uid16.c headers: utsname.h redux 2009-09-23 18:13:10 -07:00
up.c
user.c uids: Prevent tear down race 2009-11-02 16:02:39 +01:00
user_namespace.c Fix recursive lock in free_uid()/free_user_ns() 2009-02-27 16:26:21 -08:00
utsname.c utsns: extract creeate_uts_ns() 2009-06-18 13:03:55 -07:00
utsname_sysctl.c sysctl: remove "struct file *" argument of ->proc_handler 2009-09-24 07:21:04 -07:00
wait.c locking, sched: Give waitqueue spinlocks their own lockdep classes 2009-08-10 14:43:09 +02:00
workqueue.c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2009-09-11 13:23:18 -07:00