hurd: Add __pthread_spin_wait and use it

900778283ac3 ("htl: make pthread_spin_lock really spin") made
pthread_spin_lock really spin and not block, but the current users of
__pthread_spin_lock were assuming that it blocks, i.e. they use it as a
lightweight mutex fitting in just one int.

__pthread_spin_wait provides that support back.

2 files changed, 12 insertions, 3 deletions

diff --git a/sysdeps/mach/htl/bits/spin-lock-inline.h b/sysdeps/mach/htl/bits/spin-lock-inline.h
index 556bdd4..006b6fd 100644
--- a/sysdeps/mach/htl/bits/spin-lock-inline.h
+++ b/sysdeps/mach/htl/bits/spin-lock-inline.h
@@ -71,6 +71,15 @@ __pthread_spin_lock (__pthread_spinlock_t *__lock)
   return 0;
 }
 
+__PT_SPIN_INLINE int __pthread_spin_wait (__pthread_spinlock_t *__lock);
+
+__PT_SPIN_INLINE int
+__pthread_spin_wait (__pthread_spinlock_t *__lock)
+{
+  __spin_lock ((__spin_lock_t *) __lock);
+  return 0;
+}
+
 __PT_SPIN_INLINE int __pthread_spin_unlock (__pthread_spinlock_t *__lock);
 
 __PT_SPIN_INLINE int
diff --git a/sysdeps/mach/hurd/htl/pt-hurd-cond-timedwait.c b/sysdeps/mach/hurd/htl/pt-hurd-cond-timedwait.c
index 12dd863..939ed56 100644
--- a/sysdeps/mach/hurd/htl/pt-hurd-cond-timedwait.c
+++ b/sysdeps/mach/hurd/htl/pt-hurd-cond-timedwait.c
@@ -56,7 +56,7 @@ __pthread_hurd_cond_timedwait_internal (pthread_cond_t *cond,
   {
     int unblock;
 
-    __pthread_spin_lock (&cond->__lock);
+    __pthread_spin_wait (&cond->__lock);
     /* The thread only needs to be awaken if it's blocking or about to block.
        If it was already unblocked, it's not queued any more.  */
     unblock = self->prevp != NULL;
@@ -81,7 +81,7 @@ __pthread_hurd_cond_timedwait_internal (pthread_cond_t *cond,
      the condition variable's lock.  */
 
   __spin_lock (&ss->lock);
-  __pthread_spin_lock (&cond->__lock);
+  __pthread_spin_wait (&cond->__lock);
   cancel = ss->cancel;
   if (cancel)
     /* We were cancelled before doing anything.  Don't block at all.  */
@@ -123,7 +123,7 @@ __pthread_hurd_cond_timedwait_internal (pthread_cond_t *cond,
       /* As it was done when enqueueing, prevent hurd_thread_cancel from
          suspending us while the condition lock is held.  */
       __spin_lock (&ss->lock);
-      __pthread_spin_lock (&cond->__lock);
+      __pthread_spin_wait (&cond->__lock);
       if (self->prevp == NULL)
 	/* Another thread removed us from the list of waiters, which means
 	   a wakeup message has been sent.  It was either consumed while