linux-2.6.33/__mutex_lock_common()
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開始行:
*参照元 [#f0cf6b42]
#backlinks
*説明 [#ofe93605]
-パス: [[linux-2.6.33/kernel/mutex.c]]
-FIXME: これは何？
--説明
**引数 [#d2325e80]
-struct mutex *lock
--
--[[linux-2.6.33/mutex]]
-long state
--
-unsigned int subclass
--
-unsigned long ip
--
**返り値 [#m775187e]
-int
--
**参考 [#o2e836ab]
*実装 [#z99d90a8]
/*
* Lock a mutex (possibly interruptible), slowpath:
*/
static inline int __sched
-
--[[linux-2.6.33/__sched]]
__mutex_lock_common(struct mutex *lock, long state, unsi...
unsigned long ip)
{
struct task_struct *task = current;
struct mutex_waiter waiter;
unsigned long flags;
-
--[[linux-2.6.33/current(global)]]
-
--[[linux-2.6.33/task_struct]]
-
--[[linux-2.6.33/mutex_waiter]]
preempt_disable();
mutex_acquire(&lock->dep_map, subclass, 0, ip);
-
--[[linux-2.6.33/preempt_disable()]]
-
--[[linux-2.6.33/mutex_acquire()]]
#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
-
--[[linux-2.6.33/CONFIG_MUTEX_SPIN_ON_OWNER]]
/*
* Optimistic spinning.
*
* We try to spin for acquisition when we find that the...
* pending waiters and the lock owner is currently runn...
* (different) CPU.
*
* The rationale is that if the lock owner is running, ...
* release the lock soon.
*
* Since this needs the lock owner, and this mutex impl...
* doesn't track the owner atomically in the lock field...
* track it non-atomically.
*
* We can't do this for DEBUG_MUTEXES because that reli...
* to serialize everything.
*/
for (;;) {
struct thread_info *owner;
-
--[[linux-2.6.33/thread_info]]
/*
* If there's an owner, wait for it to either
* release the lock or go to sleep.
*/
owner = ACCESS_ONCE(lock->owner);
if (owner && !mutex_spin_on_owner(lock, owner))
break;
-
--[[linux-2.6.33/ACCESS_ONCE()]]
-
--[[linux-2.6.33/mutex_spin_on_owner()]]
if (atomic_cmpxchg(&lock->count, 1, 0) == 1) {
-
--[[linux-2.6.33/atomic_cmpxchg()]]
lock_acquired(&lock->dep_map, ip);
-
--[[linux-2.6.33/lock_acquired()]]
mutex_set_owner(lock);
-
--[[linux-2.6.33/mutex_set_owner()]]
preempt_enable();
-
--[[linux-2.6.33/preempt_enable()]]
return 0;
}
/*
* When there's no owner, we might have preempted betw...
* owner acquiring the lock and setting the owner fiel...
* we're an RT task that will live-lock because we won...
* the owner complete.
*/
if (!owner && (need_resched() || rt_task(task)))
break;
-
--[[linux-2.6.33/need_resched()]]
-
--[[linux-2.6.33/rt_task()]]
/*
* The cpu_relax() call is a compiler barrier which fo...
* everything in this loop to be re-loaded. We don't n...
* memory barriers as we'll eventually observe the right
* values at the cost of a few extra spins.
*/
cpu_relax();
-
--[[linux-2.6.33/cpu_relax()]]
}
#endif
spin_lock_mutex(&lock->wait_lock, flags);
-
--[[linux-2.6.33/spin_lock_mutex()]]
debug_mutex_lock_common(lock, &waiter);
debug_mutex_add_waiter(lock, &waiter, task_thread_info(...
-
--[[linux-2.6.33/debug_mutex_lock_common()]]
-
--[[linux-2.6.33/debug_mutex_add_waiter()]]
-
--[[linux-2.6.33/task_thread_info()]]
/* add waiting tasks to the end of the waitqueue (FIFO)...
list_add_tail(&waiter.list, &lock->wait_list);
waiter.task = task;
-
--[[linux-2.6.33/list_add_tail()]]
if (atomic_xchg(&lock->count, -1) == 1)
goto done;
-
--[[linux-2.6.33/atomic_xchg()]]
lock_contended(&lock->dep_map, ip);
-
--[[linux-2.6.33/lock_contended()]]
for (;;) {
/*
* Lets try to take the lock again - this is needed ev...
* we get here for the first time (shortly after faili...
* acquire the lock), to make sure that we get a wakeu...
* it's unlocked. Later on, if we sleep, this is the
* operation that gives us the lock. We xchg it to -1,...
* that when we release the lock, we properly wake up ...
* other waiters:
*/
if (atomic_xchg(&lock->count, -1) == 1)
break;
/*
* got a signal? (This code gets eliminated in the
* TASK_UNINTERRUPTIBLE case.)
*/
if (unlikely(signal_pending_state(state, task))) {
-
--[[linux-2.6.33/unlikely()]]
-
--[[linux-2.6.33/signal_pending_state()]]
mutex_remove_waiter(lock, &waiter,
task_thread_info(task));
-
--[[linux-2.6.33/mutex_remove_waiter()]]
-
--[[linux-2.6.33/task_thread_info()]]
mutex_release(&lock->dep_map, 1, ip);
spin_unlock_mutex(&lock->wait_lock, flags);
-
--[[linux-2.6.33/mutex_release()]]
-
--[[linux-2.6.33/spin_unlock_mutex()]]
debug_mutex_free_waiter(&waiter);
preempt_enable();
-
--[[linux-2.6.33/debug_mutex_free_waiter()]]
-
--[[linux-2.6.33/preempt_enable()]]
return -EINTR;
}
__set_task_state(task, state);
-
--[[linux-2.6.33/__set_task_state()]]
/* didnt get the lock, go to sleep: */
spin_unlock_mutex(&lock->wait_lock, flags);
preempt_enable_no_resched();
-
--[[linux-2.6.33/spin_unlock_mutex()]]
-
--[[linux-2.6.33/preempt_enable_no_resched()]]
schedule();
-
--[[linux-2.6.33/schedule()]]
preempt_disable();
spin_lock_mutex(&lock->wait_lock, flags);
-
--[[linux-2.6.33/preempt_disable()]]
-
--[[linux-2.6.33/spin_lock_mutex()]]
}
done:
lock_acquired(&lock->dep_map, ip);
-
--[[linux-2.6.33/lock_acquired()]]
/* got the lock - rejoice! */
mutex_remove_waiter(lock, &waiter, current_thread_info(...
mutex_set_owner(lock);
-
--[[linux-2.6.33/mutex_remove_waiter()]]
-
--[[linux-2.6.33/current_thread_info()]]
-
--[[linux-2.6.33/mutex_set_owner()]]
/* set it to 0 if there are no waiters left: */
if (likely(list_empty(&lock->wait_list)))
atomic_set(&lock->count, 0);
-
--[[linux-2.6.33/likely()]]
-
--[[linux-2.6.33/list_empty()]]
-
--[[linux-2.6.33/atomic_set()]]
spin_unlock_mutex(&lock->wait_lock, flags);
-
--[[linux-2.6.33/spin_unlock_mutex()]]
debug_mutex_free_waiter(&waiter);
preempt_enable();
-
--[[linux-2.6.33/debug_mutex_free_waiter()]]
-
--[[linux-2.6.33/preempt_enable()]]
return 0;
}
*コメント [#qed6f128]
終了行:
*参照元 [#f0cf6b42]
#backlinks
*説明 [#ofe93605]
-パス: [[linux-2.6.33/kernel/mutex.c]]
-FIXME: これは何？
--説明
**引数 [#d2325e80]
-struct mutex *lock
--
--[[linux-2.6.33/mutex]]
-long state
--
-unsigned int subclass
--
-unsigned long ip
--
**返り値 [#m775187e]
-int
--
**参考 [#o2e836ab]
*実装 [#z99d90a8]
/*
* Lock a mutex (possibly interruptible), slowpath:
*/
static inline int __sched
-
--[[linux-2.6.33/__sched]]
__mutex_lock_common(struct mutex *lock, long state, unsi...
unsigned long ip)
{
struct task_struct *task = current;
struct mutex_waiter waiter;
unsigned long flags;
-
--[[linux-2.6.33/current(global)]]
-
--[[linux-2.6.33/task_struct]]
-
--[[linux-2.6.33/mutex_waiter]]
preempt_disable();
mutex_acquire(&lock->dep_map, subclass, 0, ip);
-
--[[linux-2.6.33/preempt_disable()]]
-
--[[linux-2.6.33/mutex_acquire()]]
#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
-
--[[linux-2.6.33/CONFIG_MUTEX_SPIN_ON_OWNER]]
/*
* Optimistic spinning.
*
* We try to spin for acquisition when we find that the...
* pending waiters and the lock owner is currently runn...
* (different) CPU.
*
* The rationale is that if the lock owner is running, ...
* release the lock soon.
*
* Since this needs the lock owner, and this mutex impl...
* doesn't track the owner atomically in the lock field...
* track it non-atomically.
*
* We can't do this for DEBUG_MUTEXES because that reli...
* to serialize everything.
*/
for (;;) {
struct thread_info *owner;
-
--[[linux-2.6.33/thread_info]]
/*
* If there's an owner, wait for it to either
* release the lock or go to sleep.
*/
owner = ACCESS_ONCE(lock->owner);
if (owner && !mutex_spin_on_owner(lock, owner))
break;
-
--[[linux-2.6.33/ACCESS_ONCE()]]
-
--[[linux-2.6.33/mutex_spin_on_owner()]]
if (atomic_cmpxchg(&lock->count, 1, 0) == 1) {
-
--[[linux-2.6.33/atomic_cmpxchg()]]
lock_acquired(&lock->dep_map, ip);
-
--[[linux-2.6.33/lock_acquired()]]
mutex_set_owner(lock);
-
--[[linux-2.6.33/mutex_set_owner()]]
preempt_enable();
-
--[[linux-2.6.33/preempt_enable()]]
return 0;
}
/*
* When there's no owner, we might have preempted betw...
* owner acquiring the lock and setting the owner fiel...
* we're an RT task that will live-lock because we won...
* the owner complete.
*/
if (!owner && (need_resched() || rt_task(task)))
break;
-
--[[linux-2.6.33/need_resched()]]
-
--[[linux-2.6.33/rt_task()]]
/*
* The cpu_relax() call is a compiler barrier which fo...
* everything in this loop to be re-loaded. We don't n...
* memory barriers as we'll eventually observe the right
* values at the cost of a few extra spins.
*/
cpu_relax();
-
--[[linux-2.6.33/cpu_relax()]]
}
#endif
spin_lock_mutex(&lock->wait_lock, flags);
-
--[[linux-2.6.33/spin_lock_mutex()]]
debug_mutex_lock_common(lock, &waiter);
debug_mutex_add_waiter(lock, &waiter, task_thread_info(...
-
--[[linux-2.6.33/debug_mutex_lock_common()]]
-
--[[linux-2.6.33/debug_mutex_add_waiter()]]
-
--[[linux-2.6.33/task_thread_info()]]
/* add waiting tasks to the end of the waitqueue (FIFO)...
list_add_tail(&waiter.list, &lock->wait_list);
waiter.task = task;
-
--[[linux-2.6.33/list_add_tail()]]
if (atomic_xchg(&lock->count, -1) == 1)
goto done;
-
--[[linux-2.6.33/atomic_xchg()]]
lock_contended(&lock->dep_map, ip);
-
--[[linux-2.6.33/lock_contended()]]
for (;;) {
/*
* Lets try to take the lock again - this is needed ev...
* we get here for the first time (shortly after faili...
* acquire the lock), to make sure that we get a wakeu...
* it's unlocked. Later on, if we sleep, this is the
* operation that gives us the lock. We xchg it to -1,...
* that when we release the lock, we properly wake up ...
* other waiters:
*/
if (atomic_xchg(&lock->count, -1) == 1)
break;
/*
* got a signal? (This code gets eliminated in the
* TASK_UNINTERRUPTIBLE case.)
*/
if (unlikely(signal_pending_state(state, task))) {
-
--[[linux-2.6.33/unlikely()]]
-
--[[linux-2.6.33/signal_pending_state()]]
mutex_remove_waiter(lock, &waiter,
task_thread_info(task));
-
--[[linux-2.6.33/mutex_remove_waiter()]]
-
--[[linux-2.6.33/task_thread_info()]]
mutex_release(&lock->dep_map, 1, ip);
spin_unlock_mutex(&lock->wait_lock, flags);
-
--[[linux-2.6.33/mutex_release()]]
-
--[[linux-2.6.33/spin_unlock_mutex()]]
debug_mutex_free_waiter(&waiter);
preempt_enable();
-
--[[linux-2.6.33/debug_mutex_free_waiter()]]
-
--[[linux-2.6.33/preempt_enable()]]
return -EINTR;
}
__set_task_state(task, state);
-
--[[linux-2.6.33/__set_task_state()]]
/* didnt get the lock, go to sleep: */
spin_unlock_mutex(&lock->wait_lock, flags);
preempt_enable_no_resched();
-
--[[linux-2.6.33/spin_unlock_mutex()]]
-
--[[linux-2.6.33/preempt_enable_no_resched()]]
schedule();
-
--[[linux-2.6.33/schedule()]]
preempt_disable();
spin_lock_mutex(&lock->wait_lock, flags);
-
--[[linux-2.6.33/preempt_disable()]]
-
--[[linux-2.6.33/spin_lock_mutex()]]
}
done:
lock_acquired(&lock->dep_map, ip);
-
--[[linux-2.6.33/lock_acquired()]]
/* got the lock - rejoice! */
mutex_remove_waiter(lock, &waiter, current_thread_info(...
mutex_set_owner(lock);
-
--[[linux-2.6.33/mutex_remove_waiter()]]
-
--[[linux-2.6.33/current_thread_info()]]
-
--[[linux-2.6.33/mutex_set_owner()]]
/* set it to 0 if there are no waiters left: */
if (likely(list_empty(&lock->wait_list)))
atomic_set(&lock->count, 0);
-
--[[linux-2.6.33/likely()]]
-
--[[linux-2.6.33/list_empty()]]
-
--[[linux-2.6.33/atomic_set()]]
spin_unlock_mutex(&lock->wait_lock, flags);
-
--[[linux-2.6.33/spin_unlock_mutex()]]
debug_mutex_free_waiter(&waiter);
preempt_enable();
-
--[[linux-2.6.33/debug_mutex_free_waiter()]]
-
--[[linux-2.6.33/preempt_enable()]]
return 0;
}
*コメント [#qed6f128]
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