diff options
Diffstat (limited to 'Documentation/spinlocks.txt')
| -rw-r--r-- | Documentation/spinlocks.txt | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/Documentation/spinlocks.txt b/Documentation/spinlocks.txt index a661d684768e..471e75389778 100644 --- a/Documentation/spinlocks.txt +++ b/Documentation/spinlocks.txt @@ -1,7 +1,12 @@ -UPDATE March 21 2005 Amit Gud <gud@eth.net> +SPIN_LOCK_UNLOCKED and RW_LOCK_UNLOCKED defeat lockdep state tracking and +are hence deprecated. -Macros SPIN_LOCK_UNLOCKED and RW_LOCK_UNLOCKED are deprecated and will be -removed soon. So for any new code dynamic initialization should be used: +Please use DEFINE_SPINLOCK()/DEFINE_RWLOCK() or +__SPIN_LOCK_UNLOCKED()/__RW_LOCK_UNLOCKED() as appropriate for static +initialization. + +Dynamic initialization, when necessary, may be performed as +demonstrated below. spinlock_t xxx_lock; rwlock_t xxx_rw_lock; @@ -15,12 +20,9 @@ removed soon. So for any new code dynamic initialization should be used: module_init(xxx_init); -Reasons for deprecation - - it hurts automatic lock validators - - it becomes intrusive for the realtime preemption patches - -Following discussion is still valid, however, with the dynamic initialization -of spinlocks instead of static. +The following discussion is still valid, however, with the dynamic +initialization of spinlocks or with DEFINE_SPINLOCK, etc., used +instead of SPIN_LOCK_UNLOCKED. ----------------------- |