linux/kernel/locking
Waiman Long f0bab73cb5 locking/lockdep: Restrict the use of recursive read_lock() with qrwlock
Unlike the original unfair rwlock implementation, queued rwlock
will grant lock according to the chronological sequence of the lock
requests except when the lock requester is in the interrupt context.
Consequently, recursive read_lock calls will now hang the process if
there is a write_lock call somewhere in between the read_lock calls.

This patch updates the lockdep implementation to look for recursive
read_lock calls. A new read state (3) is used to mark those read_lock
call that cannot be recursively called except in the interrupt
context. The new read state does exhaust the 2 bits available in
held_lock:read bit field. The addition of any new read state in the
future may require a redesign of how all those bits are squeezed
together in the held_lock structure.

Signed-off-by: Waiman Long <Waiman.Long@hp.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1407345722-61615-2-git-send-email-Waiman.Long@hp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-08-13 10:33:34 +02:00
..
lglock.c locking: Move the lglocks code to kernel/locking/ 2013-11-06 09:24:20 +01:00
lockdep_internals.h lockdep: Increase static allocations 2014-04-18 14:20:50 +02:00
lockdep_proc.c lockdep/proc: Fix lock-time avg computation 2013-11-11 12:41:34 +01:00
lockdep_states.h
lockdep.c locking/lockdep: Restrict the use of recursive read_lock() with qrwlock 2014-08-13 10:33:34 +02:00
locktorture.c Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next 2014-06-03 14:00:15 -07:00
Makefile locking/rwlocks: Introduce 'qrwlocks' - fair, queued rwlocks 2014-06-06 07:58:28 +02:00
mcs_spinlock.c arch, locking: Ciao arch_mutex_cpu_relax() 2014-07-17 12:32:47 +02:00
mcs_spinlock.h locking/mcs: Remove obsolete comment 2014-08-13 10:32:00 +02:00
mutex-debug.c locking/mutex: Fix debug_mutexes 2014-04-11 10:40:35 +02:00
mutex-debug.h
mutex.c locking/Documentation: Move locking related docs into Documentation/locking/ 2014-08-13 10:32:03 +02:00
mutex.h locking/mutexes: Use MUTEX_SPIN_ON_OWNER when appropriate 2014-08-13 10:32:02 +02:00
percpu-rwsem.c locking: Move the percpu-rwsem code to kernel/locking/ 2013-11-06 09:24:22 +01:00
qrwlock.c arch, locking: Ciao arch_mutex_cpu_relax() 2014-07-17 12:32:47 +02:00
rtmutex_common.h rtmutex: Cleanup deadlock detector debug logic 2014-06-21 22:05:30 +02:00
rtmutex-debug.c rtmutex: Cleanup deadlock detector debug logic 2014-06-21 22:05:30 +02:00
rtmutex-debug.h rtmutex: Cleanup deadlock detector debug logic 2014-06-21 22:05:30 +02:00
rtmutex-tester.c locking: Move the rtmutex code to kernel/locking/ 2013-11-06 09:23:59 +01:00
rtmutex.c locking/Documentation: Move locking related docs into Documentation/locking/ 2014-08-13 10:32:03 +02:00
rtmutex.h rtmutex: Cleanup deadlock detector debug logic 2014-06-21 22:05:30 +02:00
rwsem-spinlock.c locking/rwsem: Rename 'activity' to 'count' 2014-07-16 14:56:55 +02:00
rwsem-xadd.c arch, locking: Ciao arch_mutex_cpu_relax() 2014-07-17 12:32:47 +02:00
rwsem.c locking/rwsem: Add CONFIG_RWSEM_SPIN_ON_OWNER 2014-07-16 14:57:13 +02:00
semaphore.c locking: Move the semaphore core to kernel/locking/ 2013-11-06 07:55:22 +01:00
spinlock_debug.c locking: Move the spinlock code to kernel/locking/ 2013-11-06 07:55:21 +01:00
spinlock.c locking: Move the spinlock code to kernel/locking/ 2013-11-06 07:55:21 +01:00