diff options
Diffstat (limited to 'kernel/locking')
| -rw-r--r-- | kernel/locking/lock_events_list.h | 17 | ||||
| -rw-r--r-- | kernel/locking/rwsem-xadd.c | 11 | ||||
| -rw-r--r-- | kernel/locking/rwsem.h | 4 |
3 files changed, 32 insertions, 0 deletions
diff --git a/kernel/locking/lock_events_list.h b/kernel/locking/lock_events_list.h index 8b4d2e180475..ad7668cfc9da 100644 --- a/kernel/locking/lock_events_list.h +++ b/kernel/locking/lock_events_list.h @@ -48,3 +48,20 @@ LOCK_EVENT(lock_use_node3) /* # of locking ops that use 3rd percpu node */ LOCK_EVENT(lock_use_node4) /* # of locking ops that use 4th percpu node */ LOCK_EVENT(lock_no_node) /* # of locking ops w/o using percpu node */ #endif /* CONFIG_QUEUED_SPINLOCKS */ + +/* + * Locking events for rwsem + */ +LOCK_EVENT(rwsem_sleep_reader) /* # of reader sleeps */ +LOCK_EVENT(rwsem_sleep_writer) /* # of writer sleeps */ +LOCK_EVENT(rwsem_wake_reader) /* # of reader wakeups */ +LOCK_EVENT(rwsem_wake_writer) /* # of writer wakeups */ +LOCK_EVENT(rwsem_opt_wlock) /* # of write locks opt-spin acquired */ +LOCK_EVENT(rwsem_opt_fail) /* # of failed opt-spinnings */ +LOCK_EVENT(rwsem_rlock) /* # of read locks acquired */ +LOCK_EVENT(rwsem_rlock_fast) /* # of fast read locks acquired */ +LOCK_EVENT(rwsem_rlock_fail) /* # of failed read lock acquisitions */ +LOCK_EVENT(rwsem_rtrylock) /* # of read trylock calls */ +LOCK_EVENT(rwsem_wlock) /* # of write locks acquired */ +LOCK_EVENT(rwsem_wlock_fail) /* # of failed write lock acquisitions */ +LOCK_EVENT(rwsem_wtrylock) /* # of write trylock calls */ diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c index f6198e1a58f6..6b3ee9948bf1 100644 --- a/kernel/locking/rwsem-xadd.c +++ b/kernel/locking/rwsem-xadd.c @@ -147,6 +147,7 @@ static void __rwsem_mark_wake(struct rw_semaphore *sem, * will notice the queued writer. */ wake_q_add(wake_q, waiter->task); + lockevent_inc(rwsem_wake_writer); } return; @@ -214,6 +215,7 @@ static void __rwsem_mark_wake(struct rw_semaphore *sem, } adjustment = woken * RWSEM_ACTIVE_READ_BIAS - adjustment; + lockevent_cond_inc(rwsem_wake_reader, woken); if (list_empty(&sem->wait_list)) { /* hit end of list above */ adjustment -= RWSEM_WAITING_BIAS; @@ -265,6 +267,7 @@ static inline bool rwsem_try_write_lock_unqueued(struct rw_semaphore *sem) if (atomic_long_try_cmpxchg_acquire(&sem->count, &count, count + RWSEM_ACTIVE_WRITE_BIAS)) { rwsem_set_owner(sem); + lockevent_inc(rwsem_opt_wlock); return true; } } @@ -389,6 +392,7 @@ static bool rwsem_optimistic_spin(struct rw_semaphore *sem) osq_unlock(&sem->osq); done: preempt_enable(); + lockevent_cond_inc(rwsem_opt_fail, !taken); return taken; } @@ -436,6 +440,7 @@ __rwsem_down_read_failed_common(struct rw_semaphore *sem, int state) if (atomic_long_read(&sem->count) >= 0) { raw_spin_unlock_irq(&sem->wait_lock); rwsem_set_reader_owned(sem); + lockevent_inc(rwsem_rlock_fast); return sem; } adjustment += RWSEM_WAITING_BIAS; @@ -472,9 +477,11 @@ __rwsem_down_read_failed_common(struct rw_semaphore *sem, int state) break; } schedule(); + lockevent_inc(rwsem_sleep_reader); } __set_current_state(TASK_RUNNING); + lockevent_inc(rwsem_rlock); return sem; out_nolock: list_del(&waiter.list); @@ -482,6 +489,7 @@ out_nolock: atomic_long_add(-RWSEM_WAITING_BIAS, &sem->count); raw_spin_unlock_irq(&sem->wait_lock); __set_current_state(TASK_RUNNING); + lockevent_inc(rwsem_rlock_fail); return ERR_PTR(-EINTR); } @@ -575,6 +583,7 @@ __rwsem_down_write_failed_common(struct rw_semaphore *sem, int state) goto out_nolock; schedule(); + lockevent_inc(rwsem_sleep_writer); set_current_state(state); } while ((count = atomic_long_read(&sem->count)) & RWSEM_ACTIVE_MASK); @@ -583,6 +592,7 @@ __rwsem_down_write_failed_common(struct rw_semaphore *sem, int state) __set_current_state(TASK_RUNNING); list_del(&waiter.list); raw_spin_unlock_irq(&sem->wait_lock); + lockevent_inc(rwsem_wlock); return ret; @@ -596,6 +606,7 @@ out_nolock: __rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q); raw_spin_unlock_irq(&sem->wait_lock); wake_up_q(&wake_q); + lockevent_inc(rwsem_wlock_fail); return ERR_PTR(-EINTR); } diff --git a/kernel/locking/rwsem.h b/kernel/locking/rwsem.h index 3059a2dc39f8..37db17890e36 100644 --- a/kernel/locking/rwsem.h +++ b/kernel/locking/rwsem.h @@ -23,6 +23,8 @@ * is involved. Ideally we would like to track all the readers that own * a rwsem, but the overhead is simply too big. */ +#include "lock_events.h" + #define RWSEM_READER_OWNED (1UL << 0) #define RWSEM_ANONYMOUSLY_OWNED (1UL << 1) @@ -200,6 +202,7 @@ static inline int __down_read_trylock(struct rw_semaphore *sem) */ long tmp = RWSEM_UNLOCKED_VALUE; + lockevent_inc(rwsem_rtrylock); do { if (atomic_long_try_cmpxchg_acquire(&sem->count, &tmp, tmp + RWSEM_ACTIVE_READ_BIAS)) { @@ -241,6 +244,7 @@ static inline int __down_write_trylock(struct rw_semaphore *sem) { long tmp; + lockevent_inc(rwsem_wtrylock); tmp = atomic_long_cmpxchg_acquire(&sem->count, RWSEM_UNLOCKED_VALUE, RWSEM_ACTIVE_WRITE_BIAS); if (tmp == RWSEM_UNLOCKED_VALUE) { |