Huang Ying fb842b00c5 printk: use RCU to prevent potential lock contention in kmsg_dump ... dump_list_lock is used to protect dump_list in kmsg_dumper implementation, kmsg_dump() uses it to traverse dump_list too. But if there is contention on the lock, kmsg_dump() will fail, and the valuable kernel message may be lost. This patch solves this issue with RCU. Because kmsg_dump() only read the list, no lock is needed in kmsg_dump(). So that kmsg_dump() will never fail because of lock contention. Signed-off-by: Huang Ying <ying.huang@intel.com> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2011-01-13 08:03:09 -08:00
..
debug	kdb: fix crash when KDB_BASE_CMD_MAX is exceeded	2010-11-17 13:54:57 -06:00
gcov	llseek: automatically add .llseek fop	2010-10-15 15:53:27 +02:00
irq	sched: Constify function scope static struct sched_param usage	2011-01-07 15:55:45 +01:00
power	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6	2011-01-10 08:14:53 -08:00
time	Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2011-01-07 17:02:58 -08:00
trace	Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2011-01-11 11:02:13 -08:00
.gitignore
acct.c	pass a struct path to vfs_statfs	2010-08-09 16:48:42 -04:00
async.c	async: use workqueue for worker pool	2010-07-14 11:29:46 +02:00
audit_tree.c	in untag_chunk() we need to do alloc_chunk() a bit earlier	2010-10-30 02:18:32 -04:00
audit_watch.c	audit: make functions static	2010-10-30 01:42:19 -04:00
audit.c	audit: Use rcu for task lookup protection	2010-10-30 08:45:42 -04:00
audit.h	audit: make functions static	2010-10-30 01:42:19 -04:00
auditfilter.c	Audit: add support to match lsm labels on user audit messages	2010-10-30 01:41:57 -04:00
auditsc.c	audit mmap	2010-10-30 08:45:43 -04:00
backtracetest.c
bounds.c
capability.c	sched: Remove remaining USER_SCHED code	2010-04-02 20:12:00 +02:00
cgroup_freezer.c	cgroup_freezer: update_freezer_state() does incorrect state transitions	2010-10-27 18:03:08 -07:00
cgroup.c	fs: dcache reduce branches in lookup path	2011-01-07 17:50:28 +11:00
compat.c	compat: Make compat_alloc_user_space() incorporate the access_ok()	2010-09-14 16:08:45 -07:00
configs.c	llseek: automatically add .llseek fop	2010-10-15 15:53:27 +02:00
cpu.c	Merge branches 'x86-alternatives-for-linus', 'x86-fpu-for-linus', 'x86-hwmon-for-linus', 'x86-paravirt-for-linus', 'core-locking-for-linus' and 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2011-01-06 11:11:50 -08:00
cpuset.c	convert cgroup and cpuset	2010-10-29 04:17:06 -04:00
cred.c	signals: move cred_guard_mutex from task_struct to signal_struct	2010-10-27 18:03:12 -07:00
delayacct.c
dma.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	Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2011-01-11 11:02:13 -08:00
extable.c
fork.c	Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2011-01-07 17:02:58 -08:00
freezer.c	Freezer: Fix a race during freezing of TASK_STOPPED tasks	2010-12-24 15:02:40 +01:00
futex_compat.c	futex: Address compiler warnings in exit_robust_list	2010-11-10 13:27:50 +01:00
futex.c	futex: Add futex_q static initializer	2010-11-10 15:01:34 +01:00
groups.c	kernel/groups.c: fix integer overflow in groups_search	2010-09-09 18:57:24 -07:00
hrtimer.c	Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2011-01-07 17:02:58 -08:00
hung_task.c	lockup detector: Fix grammar by adding a missing "to" in the comments	2010-08-17 09:11:52 +02:00
hw_breakpoint.c	perf: Dynamic pmu types	2010-12-16 11:36:43 +01:00
irq_work.c	irq_work: Use per cpu atomics instead of regular atomics	2010-12-18 15:54:48 +01:00
itimer.c
jump_label.c	jump label: Make arch_jump_label_text_poke_early() optional	2010-10-29 12:56:13 -04:00
kallsyms.c	Revert "kernel: make /proc/kallsyms mode 400 to reduce ease of attacking"	2010-11-19 11:54:40 -08:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec.c	use clear_page()/copy_page() in favor of memset()/memcpy() on whole pages	2010-10-26 16:52:13 -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	Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2011-01-07 17:02:58 -08:00
ksysfs.c	sysfs: add struct file* to bin_attr callbacks	2010-05-21 09:37:31 -07:00
kthread.c	sched: Constify function scope static struct sched_param usage	2011-01-07 15:55:45 +01:00
latencytop.c	latencytop: fix per task accumulator	2010-11-12 07:55:31 -08:00
lockdep_internals.h	lockdep: No need to disable preemption in debug atomic ops	2010-05-04 05:38:16 +02:00
lockdep_proc.c	locking, lockdep: Convert sprintf_symbol to %pS	2010-11-10 10:23:58 +01:00
lockdep_states.h
lockdep.c	lockdep: Check the depth of subclass	2010-10-18 18:44:26 +02:00
Makefile	kernel: clean up USE_GENERIC_SMP_HELPERS	2011-01-13 08:03:08 -08:00
module.c	module: Move RO/NX module protection to after ftrace module update	2010-12-23 09:56:00 -05:00
mutex-debug.c
mutex-debug.h
mutex.c	mutexes, sched: Introduce arch_mutex_cpu_relax()	2010-11-26 15:05:34 +01:00
mutex.h
notifier.c
ns_cgroup.c	cgroup: notify ns_cgroup deprecated	2010-10-27 18:03:09 -07:00
nsproxy.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
padata.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6	2010-08-04 15:23:14 -07:00
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_events: Add perf_event_time()	2011-01-07 15:08:51 +01:00
pid_namespace.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
pid.c	Add RCU check for find_task_by_vpid().	2010-08-19 17:18:02 -07:00
pm_qos_params.c	PM / PM QoS: Fix reversed min and max	2010-11-15 22:45:22 +01:00
posix-cpu-timers.c	posix-cpu-timers: Rcu_read_lock/unlock protect find_task_by_vpid call	2010-11-10 13:07:06 +01:00
posix-timers.c	posix-timers: Annotate lock_timer()	2010-10-21 17:30:06 +02:00
printk.c	printk: use RCU to prevent potential lock contention in kmsg_dump	2011-01-13 08:03:09 -08:00
profile.c	llseek: automatically add .llseek fop	2010-10-15 15:53:27 +02:00
ptrace.c	signals: move cred_guard_mutex from task_struct to signal_struct	2010-10-27 18:03:12 -07:00
range.c	kernel/range.c: fix clean_sort_range() for the case of full array	2010-11-12 07:55:31 -08:00
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	Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2011-01-07 17:02:58 -08:00
rcutree.h	rcu: limit rcu_node leaf-level fanout	2010-12-17 12:34:20 -08:00
relay.c	Clean up relay_alloc_page_array() slightly by using vzalloc rather than vmalloc and memset	2010-11-05 08:21:34 -07:00
res_counter.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
resource.c	resources: add arch hook for preventing allocation in reserved areas	2010-12-17 10:01:09 -08:00
rtmutex_common.h
rtmutex-debug.c
rtmutex-debug.h
rtmutex-tester.c	rtmutex-tester: make it build without BKL	2010-10-19 11:29:56 +02:00
rtmutex.c
rtmutex.h
rwsem.c
sched_autogroup.c	sched: Mark autogroup_init() __init	2011-01-07 15:54:36 +01:00
sched_autogroup.h	sched: Add 'autogroup' scheduling feature: automated per session task groups	2010-11-30 16:03:35 +01:00
sched_clock.c	sched: Add some clock info to sched_debug	2010-11-23 10:29:08 +01:00
sched_cpupri.c	sched: No need for bootmem special cases	2010-07-17 12:06:22 +02:00
sched_cpupri.h	sched: No need for bootmem special cases	2010-07-17 12:06:22 +02:00
sched_debug.c	sched: Add 'autogroup' scheduling feature: automated per session task groups	2010-11-30 16:03:35 +01:00
sched_fair.c	sched: Fix interactivity bug by charging unaccounted run-time on entity re-weight	2010-12-19 16:36:30 +01:00
sched_features.h	sched: Rewrite tg_shares_up)	2010-11-18 13:27:46 +01:00
sched_idletask.c	sched: Cure load average vs NO_HZ woes	2010-04-23 11:02:02 +02:00
sched_rt.c	sched: Implement on-demand (active) cfs_rq list	2010-11-18 13:27:47 +01:00
sched_stats.h	sched_stat: Update sched_info_queue/dequeue() code comments	2010-10-24 13:29:01 +02:00
sched_stoptask.c	sched: Fix cross-sched-class wakeup preemption	2010-11-11 14:37:23 +01:00
sched.c	sched: Fix strncmp operation	2011-01-07 15:55:10 +01:00
seccomp.c
semaphore.c
signal.c	signals: annotate lock context change on ptrace_stop()	2010-10-27 18:03:12 -07:00
smp.c	kernel: clean up USE_GENERIC_SMP_HELPERS	2011-01-13 08:03:08 -08:00
softirq.c	kernel: clean up USE_GENERIC_SMP_HELPERS	2011-01-13 08:03:08 -08:00
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: convert cpu notifier to return encapsulate errno value	2010-10-26 16:52:15 -07:00
sys_ni.c	powerpc: define a compat_sys_recv cond_syscall	2010-09-23 17:03:55 +10:00
sys.c	kmsg_dump: add kmsg_dump() calls to the reboot, halt, poweroff and emergency_restart paths	2011-01-13 08:03:07 -08:00
sysctl_binary.c	x86, NMI: Add back unknown_nmi_panic and nmi_watchdog sysctls	2010-12-10 00:01:06 +01:00
sysctl_check.c	sysctl: min/max bounds are optional	2010-10-15 14:42:24 -07:00
sysctl.c	kptr_restrict for hiding kernel pointers from unprivileged users	2011-01-13 08:03:08 -08:00
taskstats.c	Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2011-01-07 17:02:58 -08:00
test_kprobes.c	kprobes: Fix selftest to clear flags field for reusing probes	2010-10-14 08:55:27 +02:00
time.c	time: Kill off CONFIG_GENERIC_TIME	2010-07-27 12:40:54 +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	2011-01-06 10:42:43 -08:00
tracepoint.c	jump_label: Use more consistent naming	2010-10-18 19:58:56 +02:00
tsacct.c	taskstats: use real microsecond granularity for CPU times	2010-10-27 18:03:17 -07:00
uid16.c
up.c
user_namespace.c	user_ns: Introduce user_nsmap_uid and user_ns_map_gid.	2010-06-16 14:55:34 -07:00
user-return-notifier.c
user.c	fix freeing user_struct in user cache	2010-12-29 11:31:38 -08:00
utsname_sysctl.c
utsname.c
wait.c	docbook: add more wait/wake/completion to device-drivers docbook	2010-10-26 17:32:41 -07:00
watchdog.c	Merge branch 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2011-01-07 17:02:58 -08:00
workqueue_sched.h	workqueue: implement concurrency managed dynamic worker pool	2010-06-29 10:07:14 +02:00
workqueue.c	workqueue: allow chained queueing during destruction	2010-12-20 19:32:04 +01:00