linux/kernel
Paul E. McKenney 632ee20013 rcu: Introduce lockdep-based checking to RCU read-side primitives
Inspection is proving insufficient to catch all RCU misuses,
which is understandable given that rcu_dereference() might be
protected by any of four different flavors of RCU (RCU, RCU-bh,
RCU-sched, and SRCU), and might also/instead be protected by any
of a number of locking primitives. It is therefore time to
enlist the aid of lockdep.

This set of patches is inspired by earlier work by Peter
Zijlstra and Thomas Gleixner, and takes the following approach:

o	Set up separate lockdep classes for RCU, RCU-bh, and RCU-sched.

o	Set up separate lockdep classes for each instance of SRCU.

o	Create primitives that check for being in an RCU read-side
	critical section.  These return exact answers if lockdep is
	fully enabled, but if unsure, report being in an RCU read-side
	critical section.  (We want to avoid false positives!)
	The primitives are:

	For RCU: rcu_read_lock_held(void)

	For RCU-bh: rcu_read_lock_bh_held(void)

	For RCU-sched: rcu_read_lock_sched_held(void)

	For SRCU: srcu_read_lock_held(struct srcu_struct *sp)

o	Add rcu_dereference_check(), which takes a second argument
	in which one places a boolean expression based on the above
	primitives and/or lockdep_is_held().

o	A new kernel configuration parameter, CONFIG_PROVE_RCU, enables
	rcu_dereference_check().  This depends on CONFIG_PROVE_LOCKING,
	and should be quite helpful during the transition period while
	CONFIG_PROVE_RCU-unaware patches are in flight.

The existing rcu_dereference() primitive does no checking, but
upcoming patches will change that.

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
LKML-Reference: <1266887105-1528-1-git-send-email-paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-25 09:40:59 +01:00
..
gcov microblaze: Enable GCOV_PROFILE_ALL 2009-09-21 14:29:21 +02:00
irq genirq: Convert irq_desc.lock to raw_spinlock 2009-12-14 23:55:33 +01:00
power vt: introduce and use vt_kmsg_redirect() function 2009-12-15 08:53:28 -08:00
time Export the symbol of getboottime and mmonotonic_to_bootbased 2010-02-09 19:20:15 +02:00
trace tracing/kprobes: Fix probe parsing 2010-02-14 09:43:58 +01:00
.gitignore
Kconfig.freezer
Kconfig.hz
Kconfig.locks mutex: Better control mutex adaptive spinning config 2009-12-03 11:50:11 +01:00
Kconfig.preempt
Makefile Merge branch 'kvm-updates/2.6.33' of git://git.kernel.org/pub/scm/virt/kvm/kvm 2009-12-08 08:02:38 -08:00
acct.c bsdacct: fix uid/gid misreporting 2009-12-15 08:53:10 -08:00
async.c
audit.c Audit: send signal info if selinux is disabled 2009-09-24 03:50:26 -04:00
audit.h
audit_tree.c fix more leaks in audit_tree.c tag_chunk() 2009-12-19 09:27:43 -08:00
audit_watch.c Audit: reorganize struct audit_watch to save 8 bytes 2009-09-24 03:50:25 -04:00
auditfilter.c
auditsc.c Sanitize f_flags helpers 2009-12-22 12:27:34 -05:00
backtracetest.c
bounds.c kbuild: move bounds.h to include/generated 2009-12-12 13:08:14 +01:00
capability.c remove CONFIG_SECURITY_FILE_CAPABILITIES compile option 2009-11-24 15:06:47 +11:00
cgroup.c cgroups: fix to return errno in a failure path 2010-02-02 18:11:22 -08:00
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
configs.c
cpu.c sched: Correct printk whitespace in warning from cpu down task check 2010-01-28 06:59:55 +01:00
cpuset.c sched: Fix balance vs hotplug race 2009-12-06 21:10:56 +01:00
cred-internals.h
cred.c kernel/cred.c: use kmem_cache_free 2010-02-03 10:21:57 +11:00
delayacct.c headers: taskstats_kern.h trim 2009-09-18 09:48:52 -07:00
dma.c
exec_domain.c
exit.c do_wait() optimization: do not place sub-threads on task_struct->children list 2009-12-17 15:45:31 -08:00
extable.c
fork.c sched: Fix fork vs hotplug vs cpuset namespaces 2010-01-21 23:25:31 +01:00
freezer.c
futex.c futex: Handle futex value corruption gracefully 2010-02-03 15:13:22 +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
hrtimer.c hrtimers: Convert to raw_spinlocks 2009-12-14 23:55:34 +01:00
hung_task.c softlockup: Fix hung_task_check_count sysctl 2009-11-27 06:21:57 +01:00
hw_breakpoint.c perf: Make bp_len type to u64 generic across the arch 2010-02-04 01:07:12 +01:00
itimer.c itimers: Fix racy writes to cpu_itimer fields 2009-11-18 16:32:12 +01:00
kallsyms.c hw-breakpoints: Fix broken hw-breakpoint sample module 2009-11-10 11:23:29 +01:00
kexec.c Merge git://git.infradead.org/~dwmw2/mtd-2.6.33 2010-01-24 10:31:34 -08:00
kfifo.c kfifo: Don't use integer as NULL pointer 2010-02-16 15:11:08 -08:00
kgdb.c Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-02-04 16:07:41 -08:00
kmod.c kmod: fix resource leak in call_usermodehelper_pipe() 2010-01-11 09:34:04 -08:00
kprobes.c kprobes: Fix distinct type warning 2009-12-28 10:25:31 +01:00
ksysfs.c kexec: premit reduction of the reserved memory size 2009-12-16 07:20:13 -08:00
kthread.c sched: Move kthread_bind() back to kthread.c 2009-12-16 19:01:57 +01:00
latencytop.c
lockdep.c lockdep: Fix check_usage_backwards() error message 2010-01-27 08:34:02 +01:00
lockdep_internals.h
lockdep_proc.c seq_file: constify seq_operations 2009-09-23 07:39:29 -07:00
lockdep_states.h
module.c modules: Skip empty sections when exporting section notes 2010-01-06 01:11:29 -08:00
mutex-debug.c headers: remove sched.h from interrupt.h 2009-10-11 11:20:58 -07:00
mutex-debug.h locking: Implement new raw_spinlock 2009-12-14 23:55:32 +01:00
mutex.c mutex: Better control mutex adaptive spinning config 2009-12-03 11:50:11 +01:00
mutex.h
notifier.c kprobes: Fix to add __kprobes to notify_die 2009-08-30 03:08:26 +02:00
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
panic.c kmsg_dump: Dump on crash_kexec as well 2009-12-31 19:45:04 +00:00
params.c tree-wide: convert open calls to remove spaces to skip_spaces() lib function 2009-12-15 08:53:32 -08:00
perf_event.c perf_events: Fix FORK events 2010-02-14 18:10:39 +01:00
pid.c pid: reduce code size by using a pointer to iterate over array 2009-12-16 07:20:12 -08:00
pid_namespace.c pidns: deny CLONE_PARENT|CLONE_NEWPID combination 2009-09-24 07:21:04 -07:00
pm_qos_params.c pm_qos: clean up racy global "name" variable 2009-10-14 15:31:10 +02:00
posix-cpu-timers.c posix-cpu-timers: optimize and document timer_create callback 2009-11-18 12:36:05 +01:00
posix-timers.c time: Introduce CLOCK_REALTIME_COARSE 2009-08-21 21:43:46 +02:00
printk.c Merge git://git.infradead.org/~dwmw2/mtd-2.6.33 2010-01-24 10:31:34 -08:00
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: Introduce lockdep-based checking to RCU read-side primitives 2010-02-25 09:40:59 +01:00
rcutiny.c rcu: Eliminate unneeded function wrapping 2009-11-22 18:58:16 +01:00
rcutorture.c rcu: Introduce lockdep-based checking to RCU read-side primitives 2010-02-25 09:40:59 +01:00
rcutree.c rcu: Fix sparse warnings 2010-01-16 10:25:22 +01:00
rcutree.h rcu: Fix sparse warnings 2010-01-16 10:25:22 +01:00
rcutree_plugin.h rcu: Add debug check for too many rcu_read_unlock() 2010-01-13 09:06:06 +01:00
rcutree_trace.c rcu: Add expedited grace-period support for preemptible RCU 2009-12-03 11:35:25 +01:00
relay.c const: constify remaining pipe_buf_operations 2009-12-16 07:20:05 -08:00
res_counter.c memcg: some modification to softlimit under hierarchical memory reclaim. 2009-10-01 16:11:13 -07:00
resource.c resources: fix call to alignf() in allocate_resource() 2009-12-21 10:42:29 -08:00
rtmutex-debug.c sched: Convert pi_lock to raw_spinlock 2009-12-14 23:55:33 +01:00
rtmutex-debug.h
rtmutex-tester.c
rtmutex.c rtmutes: Convert rtmutex.lock to raw_spinlock 2009-12-14 23:55:33 +01:00
rtmutex.h
rtmutex_common.h
rwsem.c
sched.c sched: Fix fork vs hotplug vs cpuset namespaces 2010-01-21 23:25:31 +01:00
sched_clock.c sched: Fix cpu_clock() in NMIs, on !CONFIG_HAVE_UNSTABLE_SCHED_CLOCK 2009-12-15 09:04:36 +01:00
sched_cpupri.c sched: Convert cpupri lock to raw_spinlock 2009-12-14 23:55:33 +01:00
sched_cpupri.h sched: Convert cpupri lock to raw_spinlock 2009-12-14 23:55:33 +01:00
sched_debug.c sched: Convert rq->lock to raw_spinlock 2009-12-14 23:55:33 +01:00
sched_fair.c sched: Fix vmark regression on big machines 2010-01-21 13:39:03 +01:00
sched_features.h sched: Discard some old bits 2009-12-09 10:03:07 +01:00
sched_idletask.c sched: Restore printk sanity 2009-12-20 19:05:02 +01:00
sched_rt.c sched: Add pre and post wakeup hooks 2009-12-16 19:01:58 +01:00
sched_stats.h
seccomp.c
semaphore.c
signal.c kernel/signal.c: fix kernel information leak with print-fatal-signals=1 2010-01-11 09:34:05 -08:00
slow-work-debugfs.c SLOW_WORK: Move slow_work's proc file to debugfs 2009-12-01 08:20:31 -08:00
slow-work.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl-2.6 2009-12-08 07:38:50 -08:00
slow-work.h SLOW_WORK: Move slow_work's proc file to debugfs 2009-12-01 08:20:31 -08:00
smp.c smp_call_function_any(): pass the node value to cpumask_of_node() 2010-01-16 12:15:39 -08:00
softirq.c hrtimer, softirq: Fix hrtimer->softirq trampoline 2010-02-03 18:17:40 +01:00
softlockup.c softlockup: Add sched_clock_tick() to avoid kernel warning on kgdb resume 2010-02-01 08:22:32 +01:00
spinlock.c locking: Cleanup the name space completely 2009-12-14 23:55:33 +01:00
srcu.c rcu: Introduce lockdep-based checking to RCU read-side primitives 2010-02-25 09:40:59 +01:00
stacktrace.c
stop_machine.c
sys.c kernel/sys.c: fix missing rcu protection for sys_getpriority() 2010-02-22 19:50:34 -08:00
sys_ni.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2009-12-08 07:55:01 -08:00
sysctl.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6 2009-12-17 16:58:26 -08:00
sysctl_binary.c SYSCTL: Print binary sysctl warnings (nearly) only once 2009-12-23 21:00:20 +01:00
sysctl_check.c ipv4 05/05: add sysctl to accept packets with local source addresses 2009-12-03 12:14:38 -08:00
taskstats.c
test_kprobes.c
time.c Revert "time: Remove xtime_cache" 2009-12-22 14:10:37 -08:00
timeconst.pl
timer.c perf: Fix perf_event_do_pending() fallback callsite 2010-01-21 13:40:39 +01:00
tracepoint.c trivial: fix typo "to to" in multiple files 2009-09-21 15:14:55 +02:00
tsacct.c
uid16.c headers: utsname.h redux 2009-09-23 18:13:10 -07:00
up.c
user-return-notifier.c core: Clean up user return notifers use of per_cpu 2009-12-02 10:22:59 +01:00
user.c uids: Prevent tear down race 2009-11-02 16:02:39 +01:00
user_namespace.c
utsname.c
utsname_sysctl.c sysctl kernel: Remove binary sysctl logic 2009-11-12 02:04:55 -08:00
wait.c locking, sched: Give waitqueue spinlocks their own lockdep classes 2009-08-10 14:43:09 +02:00
workqueue.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 2009-12-10 09:35:44 -08:00