mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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Merge branch 'futexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'futexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: futex: fix restart in wait_requeue_pi futex: fix restart for early wakeup in futex_wait_requeue_pi() futex: cleanup error exit futex: remove the wait queue futex: add requeue-pi documentation futex: remove FUTEX_REQUEUE_PI (non CMP) futex: fix futex_wait_setup key handling sparc64: extend TI_RESTART_BLOCK space by 8 bytes futex: fixup unlocked requeue pi case futex: add requeue_pi functionality futex: split out futex value validation code futex: distangle futex_requeue() futex: add FUTEX_HAS_TIMEOUT flag to restart.futex.flags rt_mutex: add proxy lock routines futex: split out fixup owner logic from futex_lock_pi() futex: split out atomic logic from futex_lock_pi() futex: add helper to find the top prio waiter of a futex futex: separate futex_wait_queue_me() logic from futex_wait()
This commit is contained in:
commit
75063600fd
7 changed files with 1254 additions and 384 deletions
131
Documentation/futex-requeue-pi.txt
Normal file
131
Documentation/futex-requeue-pi.txt
Normal file
|
@ -0,0 +1,131 @@
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|||
Futex Requeue PI
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----------------
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Requeueing of tasks from a non-PI futex to a PI futex requires
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special handling in order to ensure the underlying rt_mutex is never
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left without an owner if it has waiters; doing so would break the PI
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boosting logic [see rt-mutex-desgin.txt] For the purposes of
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brevity, this action will be referred to as "requeue_pi" throughout
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this document. Priority inheritance is abbreviated throughout as
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"PI".
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Motivation
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----------
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Without requeue_pi, the glibc implementation of
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pthread_cond_broadcast() must resort to waking all the tasks waiting
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on a pthread_condvar and letting them try to sort out which task
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gets to run first in classic thundering-herd formation. An ideal
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implementation would wake the highest-priority waiter, and leave the
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rest to the natural wakeup inherent in unlocking the mutex
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associated with the condvar.
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Consider the simplified glibc calls:
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/* caller must lock mutex */
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pthread_cond_wait(cond, mutex)
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{
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lock(cond->__data.__lock);
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unlock(mutex);
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do {
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unlock(cond->__data.__lock);
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futex_wait(cond->__data.__futex);
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lock(cond->__data.__lock);
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} while(...)
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unlock(cond->__data.__lock);
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lock(mutex);
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}
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pthread_cond_broadcast(cond)
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{
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lock(cond->__data.__lock);
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unlock(cond->__data.__lock);
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futex_requeue(cond->data.__futex, cond->mutex);
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}
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Once pthread_cond_broadcast() requeues the tasks, the cond->mutex
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has waiters. Note that pthread_cond_wait() attempts to lock the
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mutex only after it has returned to user space. This will leave the
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underlying rt_mutex with waiters, and no owner, breaking the
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previously mentioned PI-boosting algorithms.
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In order to support PI-aware pthread_condvar's, the kernel needs to
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be able to requeue tasks to PI futexes. This support implies that
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upon a successful futex_wait system call, the caller would return to
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user space already holding the PI futex. The glibc implementation
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would be modified as follows:
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/* caller must lock mutex */
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pthread_cond_wait_pi(cond, mutex)
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{
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lock(cond->__data.__lock);
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unlock(mutex);
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do {
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unlock(cond->__data.__lock);
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futex_wait_requeue_pi(cond->__data.__futex);
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lock(cond->__data.__lock);
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} while(...)
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unlock(cond->__data.__lock);
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/* the kernel acquired the the mutex for us */
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}
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pthread_cond_broadcast_pi(cond)
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{
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lock(cond->__data.__lock);
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unlock(cond->__data.__lock);
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futex_requeue_pi(cond->data.__futex, cond->mutex);
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}
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The actual glibc implementation will likely test for PI and make the
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necessary changes inside the existing calls rather than creating new
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calls for the PI cases. Similar changes are needed for
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pthread_cond_timedwait() and pthread_cond_signal().
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Implementation
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--------------
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In order to ensure the rt_mutex has an owner if it has waiters, it
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is necessary for both the requeue code, as well as the waiting code,
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to be able to acquire the rt_mutex before returning to user space.
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The requeue code cannot simply wake the waiter and leave it to
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acquire the rt_mutex as it would open a race window between the
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requeue call returning to user space and the waiter waking and
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starting to run. This is especially true in the uncontended case.
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The solution involves two new rt_mutex helper routines,
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rt_mutex_start_proxy_lock() and rt_mutex_finish_proxy_lock(), which
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allow the requeue code to acquire an uncontended rt_mutex on behalf
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of the waiter and to enqueue the waiter on a contended rt_mutex.
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Two new system calls provide the kernel<->user interface to
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requeue_pi: FUTEX_WAIT_REQUEUE_PI and FUTEX_REQUEUE_CMP_PI.
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FUTEX_WAIT_REQUEUE_PI is called by the waiter (pthread_cond_wait()
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and pthread_cond_timedwait()) to block on the initial futex and wait
|
||||
to be requeued to a PI-aware futex. The implementation is the
|
||||
result of a high-speed collision between futex_wait() and
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futex_lock_pi(), with some extra logic to check for the additional
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wake-up scenarios.
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FUTEX_REQUEUE_CMP_PI is called by the waker
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(pthread_cond_broadcast() and pthread_cond_signal()) to requeue and
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possibly wake the waiting tasks. Internally, this system call is
|
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still handled by futex_requeue (by passing requeue_pi=1). Before
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requeueing, futex_requeue() attempts to acquire the requeue target
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PI futex on behalf of the top waiter. If it can, this waiter is
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woken. futex_requeue() then proceeds to requeue the remaining
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nr_wake+nr_requeue tasks to the PI futex, calling
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rt_mutex_start_proxy_lock() prior to each requeue to prepare the
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task as a waiter on the underlying rt_mutex. It is possible that
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the lock can be acquired at this stage as well, if so, the next
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waiter is woken to finish the acquisition of the lock.
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FUTEX_REQUEUE_PI accepts nr_wake and nr_requeue as arguments, but
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their sum is all that really matters. futex_requeue() will wake or
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requeue up to nr_wake + nr_requeue tasks. It will wake only as many
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tasks as it can acquire the lock for, which in the majority of cases
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should be 0 as good programming practice dictates that the caller of
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either pthread_cond_broadcast() or pthread_cond_signal() acquire the
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mutex prior to making the call. FUTEX_REQUEUE_PI requires that
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nr_wake=1. nr_requeue should be INT_MAX for broadcast and 0 for
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signal.
|
|
@ -102,8 +102,8 @@ struct thread_info {
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#define TI_KERN_CNTD1 0x00000488
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#define TI_PCR 0x00000490
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#define TI_RESTART_BLOCK 0x00000498
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#define TI_KUNA_REGS 0x000004c0
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#define TI_KUNA_INSN 0x000004c8
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#define TI_KUNA_REGS 0x000004c8
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#define TI_KUNA_INSN 0x000004d0
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#define TI_FPREGS 0x00000500
|
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|
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/* We embed this in the uppermost byte of thread_info->flags */
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|
|
|
@ -23,6 +23,8 @@ union ktime;
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#define FUTEX_TRYLOCK_PI 8
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#define FUTEX_WAIT_BITSET 9
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#define FUTEX_WAKE_BITSET 10
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#define FUTEX_WAIT_REQUEUE_PI 11
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#define FUTEX_CMP_REQUEUE_PI 12
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#define FUTEX_PRIVATE_FLAG 128
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#define FUTEX_CLOCK_REALTIME 256
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|
@ -38,6 +40,10 @@ union ktime;
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#define FUTEX_TRYLOCK_PI_PRIVATE (FUTEX_TRYLOCK_PI | FUTEX_PRIVATE_FLAG)
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#define FUTEX_WAIT_BITSET_PRIVATE (FUTEX_WAIT_BITS | FUTEX_PRIVATE_FLAG)
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#define FUTEX_WAKE_BITSET_PRIVATE (FUTEX_WAKE_BITS | FUTEX_PRIVATE_FLAG)
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#define FUTEX_WAIT_REQUEUE_PI_PRIVATE (FUTEX_WAIT_REQUEUE_PI | \
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FUTEX_PRIVATE_FLAG)
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#define FUTEX_CMP_REQUEUE_PI_PRIVATE (FUTEX_CMP_REQUEUE_PI | \
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FUTEX_PRIVATE_FLAG)
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/*
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* Support for robust futexes: the kernel cleans up held futexes at
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||||
|
|
|
@ -21,13 +21,14 @@ struct restart_block {
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|||
struct {
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unsigned long arg0, arg1, arg2, arg3;
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};
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/* For futex_wait */
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/* For futex_wait and futex_wait_requeue_pi */
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struct {
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u32 *uaddr;
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u32 val;
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u32 flags;
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u32 bitset;
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u64 time;
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u32 *uaddr2;
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} futex;
|
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/* For nanosleep */
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struct {
|
||||
|
|
1198
kernel/futex.c
1198
kernel/futex.c
File diff suppressed because it is too large
Load diff
288
kernel/rtmutex.c
288
kernel/rtmutex.c
|
@ -300,7 +300,8 @@ static int rt_mutex_adjust_prio_chain(struct task_struct *task,
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|||
* assigned pending owner [which might not have taken the
|
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* lock yet]:
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*/
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static inline int try_to_steal_lock(struct rt_mutex *lock)
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static inline int try_to_steal_lock(struct rt_mutex *lock,
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struct task_struct *task)
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{
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struct task_struct *pendowner = rt_mutex_owner(lock);
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struct rt_mutex_waiter *next;
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|
@ -309,11 +310,11 @@ static inline int try_to_steal_lock(struct rt_mutex *lock)
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if (!rt_mutex_owner_pending(lock))
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return 0;
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if (pendowner == current)
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if (pendowner == task)
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return 1;
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spin_lock_irqsave(&pendowner->pi_lock, flags);
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if (current->prio >= pendowner->prio) {
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if (task->prio >= pendowner->prio) {
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spin_unlock_irqrestore(&pendowner->pi_lock, flags);
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return 0;
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}
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|
@ -338,21 +339,21 @@ static inline int try_to_steal_lock(struct rt_mutex *lock)
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* We are going to steal the lock and a waiter was
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* enqueued on the pending owners pi_waiters queue. So
|
||||
* we have to enqueue this waiter into
|
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* current->pi_waiters list. This covers the case,
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* where current is boosted because it holds another
|
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* task->pi_waiters list. This covers the case,
|
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* where task is boosted because it holds another
|
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* lock and gets unboosted because the booster is
|
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* interrupted, so we would delay a waiter with higher
|
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* priority as current->normal_prio.
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* priority as task->normal_prio.
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*
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* Note: in the rare case of a SCHED_OTHER task changing
|
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* its priority and thus stealing the lock, next->task
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* might be current:
|
||||
* might be task:
|
||||
*/
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if (likely(next->task != current)) {
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spin_lock_irqsave(¤t->pi_lock, flags);
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plist_add(&next->pi_list_entry, ¤t->pi_waiters);
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__rt_mutex_adjust_prio(current);
|
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spin_unlock_irqrestore(¤t->pi_lock, flags);
|
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if (likely(next->task != task)) {
|
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spin_lock_irqsave(&task->pi_lock, flags);
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plist_add(&next->pi_list_entry, &task->pi_waiters);
|
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__rt_mutex_adjust_prio(task);
|
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spin_unlock_irqrestore(&task->pi_lock, flags);
|
||||
}
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return 1;
|
||||
}
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||||
|
@ -389,7 +390,7 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock)
|
|||
*/
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mark_rt_mutex_waiters(lock);
|
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|
||||
if (rt_mutex_owner(lock) && !try_to_steal_lock(lock))
|
||||
if (rt_mutex_owner(lock) && !try_to_steal_lock(lock, current))
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return 0;
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||||
|
||||
/* We got the lock. */
|
||||
|
@ -411,6 +412,7 @@ static int try_to_take_rt_mutex(struct rt_mutex *lock)
|
|||
*/
|
||||
static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
|
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struct rt_mutex_waiter *waiter,
|
||||
struct task_struct *task,
|
||||
int detect_deadlock)
|
||||
{
|
||||
struct task_struct *owner = rt_mutex_owner(lock);
|
||||
|
@ -418,21 +420,21 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
|
|||
unsigned long flags;
|
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int chain_walk = 0, res;
|
||||
|
||||
spin_lock_irqsave(¤t->pi_lock, flags);
|
||||
__rt_mutex_adjust_prio(current);
|
||||
waiter->task = current;
|
||||
spin_lock_irqsave(&task->pi_lock, flags);
|
||||
__rt_mutex_adjust_prio(task);
|
||||
waiter->task = task;
|
||||
waiter->lock = lock;
|
||||
plist_node_init(&waiter->list_entry, current->prio);
|
||||
plist_node_init(&waiter->pi_list_entry, current->prio);
|
||||
plist_node_init(&waiter->list_entry, task->prio);
|
||||
plist_node_init(&waiter->pi_list_entry, task->prio);
|
||||
|
||||
/* Get the top priority waiter on the lock */
|
||||
if (rt_mutex_has_waiters(lock))
|
||||
top_waiter = rt_mutex_top_waiter(lock);
|
||||
plist_add(&waiter->list_entry, &lock->wait_list);
|
||||
|
||||
current->pi_blocked_on = waiter;
|
||||
task->pi_blocked_on = waiter;
|
||||
|
||||
spin_unlock_irqrestore(¤t->pi_lock, flags);
|
||||
spin_unlock_irqrestore(&task->pi_lock, flags);
|
||||
|
||||
if (waiter == rt_mutex_top_waiter(lock)) {
|
||||
spin_lock_irqsave(&owner->pi_lock, flags);
|
||||
|
@ -460,7 +462,7 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock,
|
|||
spin_unlock(&lock->wait_lock);
|
||||
|
||||
res = rt_mutex_adjust_prio_chain(owner, detect_deadlock, lock, waiter,
|
||||
current);
|
||||
task);
|
||||
|
||||
spin_lock(&lock->wait_lock);
|
||||
|
||||
|
@ -605,6 +607,85 @@ void rt_mutex_adjust_pi(struct task_struct *task)
|
|||
rt_mutex_adjust_prio_chain(task, 0, NULL, NULL, task);
|
||||
}
|
||||
|
||||
/**
|
||||
* __rt_mutex_slowlock() - Perform the wait-wake-try-to-take loop
|
||||
* @lock: the rt_mutex to take
|
||||
* @state: the state the task should block in (TASK_INTERRUPTIBLE
|
||||
* or TASK_UNINTERRUPTIBLE)
|
||||
* @timeout: the pre-initialized and started timer, or NULL for none
|
||||
* @waiter: the pre-initialized rt_mutex_waiter
|
||||
* @detect_deadlock: passed to task_blocks_on_rt_mutex
|
||||
*
|
||||
* lock->wait_lock must be held by the caller.
|
||||
*/
|
||||
static int __sched
|
||||
__rt_mutex_slowlock(struct rt_mutex *lock, int state,
|
||||
struct hrtimer_sleeper *timeout,
|
||||
struct rt_mutex_waiter *waiter,
|
||||
int detect_deadlock)
|
||||
{
|
||||
int ret = 0;
|
||||
|
||||
for (;;) {
|
||||
/* Try to acquire the lock: */
|
||||
if (try_to_take_rt_mutex(lock))
|
||||
break;
|
||||
|
||||
/*
|
||||
* TASK_INTERRUPTIBLE checks for signals and
|
||||
* timeout. Ignored otherwise.
|
||||
*/
|
||||
if (unlikely(state == TASK_INTERRUPTIBLE)) {
|
||||
/* Signal pending? */
|
||||
if (signal_pending(current))
|
||||
ret = -EINTR;
|
||||
if (timeout && !timeout->task)
|
||||
ret = -ETIMEDOUT;
|
||||
if (ret)
|
||||
break;
|
||||
}
|
||||
|
||||
/*
|
||||
* waiter->task is NULL the first time we come here and
|
||||
* when we have been woken up by the previous owner
|
||||
* but the lock got stolen by a higher prio task.
|
||||
*/
|
||||
if (!waiter->task) {
|
||||
ret = task_blocks_on_rt_mutex(lock, waiter, current,
|
||||
detect_deadlock);
|
||||
/*
|
||||
* If we got woken up by the owner then start loop
|
||||
* all over without going into schedule to try
|
||||
* to get the lock now:
|
||||
*/
|
||||
if (unlikely(!waiter->task)) {
|
||||
/*
|
||||
* Reset the return value. We might
|
||||
* have returned with -EDEADLK and the
|
||||
* owner released the lock while we
|
||||
* were walking the pi chain.
|
||||
*/
|
||||
ret = 0;
|
||||
continue;
|
||||
}
|
||||
if (unlikely(ret))
|
||||
break;
|
||||
}
|
||||
|
||||
spin_unlock(&lock->wait_lock);
|
||||
|
||||
debug_rt_mutex_print_deadlock(waiter);
|
||||
|
||||
if (waiter->task)
|
||||
schedule_rt_mutex(lock);
|
||||
|
||||
spin_lock(&lock->wait_lock);
|
||||
set_current_state(state);
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Slow path lock function:
|
||||
*/
|
||||
|
@ -636,62 +717,8 @@ rt_mutex_slowlock(struct rt_mutex *lock, int state,
|
|||
timeout->task = NULL;
|
||||
}
|
||||
|
||||
for (;;) {
|
||||
/* Try to acquire the lock: */
|
||||
if (try_to_take_rt_mutex(lock))
|
||||
break;
|
||||
|
||||
/*
|
||||
* TASK_INTERRUPTIBLE checks for signals and
|
||||
* timeout. Ignored otherwise.
|
||||
*/
|
||||
if (unlikely(state == TASK_INTERRUPTIBLE)) {
|
||||
/* Signal pending? */
|
||||
if (signal_pending(current))
|
||||
ret = -EINTR;
|
||||
if (timeout && !timeout->task)
|
||||
ret = -ETIMEDOUT;
|
||||
if (ret)
|
||||
break;
|
||||
}
|
||||
|
||||
/*
|
||||
* waiter.task is NULL the first time we come here and
|
||||
* when we have been woken up by the previous owner
|
||||
* but the lock got stolen by a higher prio task.
|
||||
*/
|
||||
if (!waiter.task) {
|
||||
ret = task_blocks_on_rt_mutex(lock, &waiter,
|
||||
detect_deadlock);
|
||||
/*
|
||||
* If we got woken up by the owner then start loop
|
||||
* all over without going into schedule to try
|
||||
* to get the lock now:
|
||||
*/
|
||||
if (unlikely(!waiter.task)) {
|
||||
/*
|
||||
* Reset the return value. We might
|
||||
* have returned with -EDEADLK and the
|
||||
* owner released the lock while we
|
||||
* were walking the pi chain.
|
||||
*/
|
||||
ret = 0;
|
||||
continue;
|
||||
}
|
||||
if (unlikely(ret))
|
||||
break;
|
||||
}
|
||||
|
||||
spin_unlock(&lock->wait_lock);
|
||||
|
||||
debug_rt_mutex_print_deadlock(&waiter);
|
||||
|
||||
if (waiter.task)
|
||||
schedule_rt_mutex(lock);
|
||||
|
||||
spin_lock(&lock->wait_lock);
|
||||
set_current_state(state);
|
||||
}
|
||||
ret = __rt_mutex_slowlock(lock, state, timeout, &waiter,
|
||||
detect_deadlock);
|
||||
|
||||
set_current_state(TASK_RUNNING);
|
||||
|
||||
|
@ -985,6 +1012,59 @@ void rt_mutex_proxy_unlock(struct rt_mutex *lock,
|
|||
rt_mutex_deadlock_account_unlock(proxy_owner);
|
||||
}
|
||||
|
||||
/**
|
||||
* rt_mutex_start_proxy_lock() - Start lock acquisition for another task
|
||||
* @lock: the rt_mutex to take
|
||||
* @waiter: the pre-initialized rt_mutex_waiter
|
||||
* @task: the task to prepare
|
||||
* @detect_deadlock: perform deadlock detection (1) or not (0)
|
||||
*
|
||||
* Returns:
|
||||
* 0 - task blocked on lock
|
||||
* 1 - acquired the lock for task, caller should wake it up
|
||||
* <0 - error
|
||||
*
|
||||
* Special API call for FUTEX_REQUEUE_PI support.
|
||||
*/
|
||||
int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
|
||||
struct rt_mutex_waiter *waiter,
|
||||
struct task_struct *task, int detect_deadlock)
|
||||
{
|
||||
int ret;
|
||||
|
||||
spin_lock(&lock->wait_lock);
|
||||
|
||||
mark_rt_mutex_waiters(lock);
|
||||
|
||||
if (!rt_mutex_owner(lock) || try_to_steal_lock(lock, task)) {
|
||||
/* We got the lock for task. */
|
||||
debug_rt_mutex_lock(lock);
|
||||
|
||||
rt_mutex_set_owner(lock, task, 0);
|
||||
|
||||
rt_mutex_deadlock_account_lock(lock, task);
|
||||
return 1;
|
||||
}
|
||||
|
||||
ret = task_blocks_on_rt_mutex(lock, waiter, task, detect_deadlock);
|
||||
|
||||
|
||||
if (ret && !waiter->task) {
|
||||
/*
|
||||
* Reset the return value. We might have
|
||||
* returned with -EDEADLK and the owner
|
||||
* released the lock while we were walking the
|
||||
* pi chain. Let the waiter sort it out.
|
||||
*/
|
||||
ret = 0;
|
||||
}
|
||||
spin_unlock(&lock->wait_lock);
|
||||
|
||||
debug_rt_mutex_print_deadlock(waiter);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/**
|
||||
* rt_mutex_next_owner - return the next owner of the lock
|
||||
*
|
||||
|
@ -1004,3 +1084,57 @@ struct task_struct *rt_mutex_next_owner(struct rt_mutex *lock)
|
|||
|
||||
return rt_mutex_top_waiter(lock)->task;
|
||||
}
|
||||
|
||||
/**
|
||||
* rt_mutex_finish_proxy_lock() - Complete lock acquisition
|
||||
* @lock: the rt_mutex we were woken on
|
||||
* @to: the timeout, null if none. hrtimer should already have
|
||||
* been started.
|
||||
* @waiter: the pre-initialized rt_mutex_waiter
|
||||
* @detect_deadlock: perform deadlock detection (1) or not (0)
|
||||
*
|
||||
* Complete the lock acquisition started our behalf by another thread.
|
||||
*
|
||||
* Returns:
|
||||
* 0 - success
|
||||
* <0 - error, one of -EINTR, -ETIMEDOUT, or -EDEADLK
|
||||
*
|
||||
* Special API call for PI-futex requeue support
|
||||
*/
|
||||
int rt_mutex_finish_proxy_lock(struct rt_mutex *lock,
|
||||
struct hrtimer_sleeper *to,
|
||||
struct rt_mutex_waiter *waiter,
|
||||
int detect_deadlock)
|
||||
{
|
||||
int ret;
|
||||
|
||||
spin_lock(&lock->wait_lock);
|
||||
|
||||
set_current_state(TASK_INTERRUPTIBLE);
|
||||
|
||||
ret = __rt_mutex_slowlock(lock, TASK_INTERRUPTIBLE, to, waiter,
|
||||
detect_deadlock);
|
||||
|
||||
set_current_state(TASK_RUNNING);
|
||||
|
||||
if (unlikely(waiter->task))
|
||||
remove_waiter(lock, waiter);
|
||||
|
||||
/*
|
||||
* try_to_take_rt_mutex() sets the waiter bit unconditionally. We might
|
||||
* have to fix that up.
|
||||
*/
|
||||
fixup_rt_mutex_waiters(lock);
|
||||
|
||||
spin_unlock(&lock->wait_lock);
|
||||
|
||||
/*
|
||||
* Readjust priority, when we did not get the lock. We might have been
|
||||
* the pending owner and boosted. Since we did not take the lock, the
|
||||
* PI boost has to go.
|
||||
*/
|
||||
if (unlikely(ret))
|
||||
rt_mutex_adjust_prio(current);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
|
|
@ -120,6 +120,14 @@ extern void rt_mutex_init_proxy_locked(struct rt_mutex *lock,
|
|||
struct task_struct *proxy_owner);
|
||||
extern void rt_mutex_proxy_unlock(struct rt_mutex *lock,
|
||||
struct task_struct *proxy_owner);
|
||||
extern int rt_mutex_start_proxy_lock(struct rt_mutex *lock,
|
||||
struct rt_mutex_waiter *waiter,
|
||||
struct task_struct *task,
|
||||
int detect_deadlock);
|
||||
extern int rt_mutex_finish_proxy_lock(struct rt_mutex *lock,
|
||||
struct hrtimer_sleeper *to,
|
||||
struct rt_mutex_waiter *waiter,
|
||||
int detect_deadlock);
|
||||
|
||||
#ifdef CONFIG_DEBUG_RT_MUTEXES
|
||||
# include "rtmutex-debug.h"
|
||||
|
|
Loading…
Reference in a new issue