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authorUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
committerUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
commita334319f6530564d22e775935d9c91663623a1b4 (patch)
treeb5877475619e4c938e98757d518bb1e9cbead751 /nptl/pthread_mutex_lock.c
parent0ecb606cb6cf65de1d9fc8a919bceb4be476c602 (diff)
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(CFLAGS-tst-align.c): Add -mpreferred-stack-boundary=4.
Diffstat (limited to 'nptl/pthread_mutex_lock.c')
-rw-r--r--nptl/pthread_mutex_lock.c333
1 files changed, 6 insertions, 327 deletions
diff --git a/nptl/pthread_mutex_lock.c b/nptl/pthread_mutex_lock.c
index 1c3ee4fe25..ee39f20820 100644
--- a/nptl/pthread_mutex_lock.c
+++ b/nptl/pthread_mutex_lock.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002,2003,2004,2005,2006,2007 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -19,9 +19,6 @@
 
 #include <assert.h>
 #include <errno.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <not-cancel.h>
 #include "pthreadP.h"
 #include <lowlevellock.h>
 
@@ -29,7 +26,6 @@
 #ifndef LLL_MUTEX_LOCK
 # define LLL_MUTEX_LOCK(mutex) lll_mutex_lock (mutex)
 # define LLL_MUTEX_TRYLOCK(mutex) lll_mutex_trylock (mutex)
-# define LLL_ROBUST_MUTEX_LOCK(mutex, id) lll_robust_mutex_lock (mutex, id)
 #endif
 
 
@@ -39,10 +35,8 @@ __pthread_mutex_lock (mutex)
 {
   assert (sizeof (mutex->__size) >= sizeof (mutex->__data));
 
-  int oldval;
   pid_t id = THREAD_GETMEM (THREAD_SELF, tid);
 
-  int retval = 0;
   switch (__builtin_expect (mutex->__data.__kind, PTHREAD_MUTEX_TIMED_NP))
     {
       /* Recursive mutex.  */
@@ -63,23 +57,23 @@ __pthread_mutex_lock (mutex)
       /* We have to get the mutex.  */
       LLL_MUTEX_LOCK (mutex->__data.__lock);
 
-      assert (mutex->__data.__owner == 0);
       mutex->__data.__count = 1;
       break;
 
       /* Error checking mutex.  */
     case PTHREAD_MUTEX_ERRORCHECK_NP:
       /* Check whether we already hold the mutex.  */
-      if (__builtin_expect (mutex->__data.__owner == id, 0))
+      if (mutex->__data.__owner == id)
 	return EDEADLK;
 
       /* FALLTHROUGH */
 
+    default:
+      /* Correct code cannot set any other type.  */
     case PTHREAD_MUTEX_TIMED_NP:
     simple:
       /* Normal mutex.  */
       LLL_MUTEX_LOCK (mutex->__data.__lock);
-      assert (mutex->__data.__owner == 0);
       break;
 
     case PTHREAD_MUTEX_ADAPTIVE_NP:
@@ -107,332 +101,17 @@ __pthread_mutex_lock (mutex)
 
 	  mutex->__data.__spins += (cnt - mutex->__data.__spins) / 8;
 	}
-      assert (mutex->__data.__owner == 0);
       break;
-
-    case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP:
-    case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP:
-    case PTHREAD_MUTEX_ROBUST_NORMAL_NP:
-    case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP:
-      THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending,
-		     &mutex->__data.__list.__next);
-
-      oldval = mutex->__data.__lock;
-      do
-	{
-	again:
-	  if ((oldval & FUTEX_OWNER_DIED) != 0)
-	    {
-	      /* The previous owner died.  Try locking the mutex.  */
-	      int newval = id;
-#ifdef NO_INCR
-	      newval |= FUTEX_WAITERS;
-#else
-	      newval |= (oldval & FUTEX_WAITERS);
-#endif
-
-	      newval
-		= atomic_compare_and_exchange_val_acq (&mutex->__data.__lock,
-						       newval, oldval);
-
-	      if (newval != oldval)
-		{
-		  oldval = newval;
-		  goto again;
-		}
-
-	      /* We got the mutex.  */
-	      mutex->__data.__count = 1;
-	      /* But it is inconsistent unless marked otherwise.  */
-	      mutex->__data.__owner = PTHREAD_MUTEX_INCONSISTENT;
-
-	      ENQUEUE_MUTEX (mutex);
-	      THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
-
-	      /* Note that we deliberately exit here.  If we fall
-		 through to the end of the function __nusers would be
-		 incremented which is not correct because the old
-		 owner has to be discounted.  If we are not supposed
-		 to increment __nusers we actually have to decrement
-		 it here.  */
-#ifdef NO_INCR
-	      --mutex->__data.__nusers;
-#endif
-
-	      return EOWNERDEAD;
-	    }
-
-	  /* Check whether we already hold the mutex.  */
-	  if (__builtin_expect ((oldval & FUTEX_TID_MASK) == id, 0))
-	    {
-	      if (mutex->__data.__kind
-		  == PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP)
-		{
-		  THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending,
-				 NULL);
-		  return EDEADLK;
-		}
-
-	      if (mutex->__data.__kind
-		  == PTHREAD_MUTEX_ROBUST_RECURSIVE_NP)
-		{
-		  THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending,
-				 NULL);
-
-		  /* Just bump the counter.  */
-		  if (__builtin_expect (mutex->__data.__count + 1 == 0, 0))
-		    /* Overflow of the counter.  */
-		    return EAGAIN;
-
-		  ++mutex->__data.__count;
-
-		  return 0;
-		}
-	    }
-
-	  oldval = LLL_ROBUST_MUTEX_LOCK (mutex->__data.__lock, id);
-
-	  if (__builtin_expect (mutex->__data.__owner
-				== PTHREAD_MUTEX_NOTRECOVERABLE, 0))
-	    {
-	      /* This mutex is now not recoverable.  */
-	      mutex->__data.__count = 0;
-	      lll_mutex_unlock (mutex->__data.__lock);
-	      THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
-	      return ENOTRECOVERABLE;
-	    }
-	}
-      while ((oldval & FUTEX_OWNER_DIED) != 0);
-
-      mutex->__data.__count = 1;
-      ENQUEUE_MUTEX (mutex);
-      THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
-      break;
-
-    case PTHREAD_MUTEX_PI_RECURSIVE_NP:
-    case PTHREAD_MUTEX_PI_ERRORCHECK_NP:
-    case PTHREAD_MUTEX_PI_NORMAL_NP:
-    case PTHREAD_MUTEX_PI_ADAPTIVE_NP:
-    case PTHREAD_MUTEX_PI_ROBUST_RECURSIVE_NP:
-    case PTHREAD_MUTEX_PI_ROBUST_ERRORCHECK_NP:
-    case PTHREAD_MUTEX_PI_ROBUST_NORMAL_NP:
-    case PTHREAD_MUTEX_PI_ROBUST_ADAPTIVE_NP:
-      {
-	int kind = mutex->__data.__kind & PTHREAD_MUTEX_KIND_MASK_NP;
-	int robust = mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP;
-
-	if (robust)
-	  /* Note: robust PI futexes are signaled by setting bit 0.  */
-	  THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending,
-			 (void *) (((uintptr_t) &mutex->__data.__list.__next)
-				   | 1));
-
-	oldval = mutex->__data.__lock;
-
-	/* Check whether we already hold the mutex.  */
-	if (__builtin_expect ((oldval & FUTEX_TID_MASK) == id, 0))
-	  {
-	    if (kind == PTHREAD_MUTEX_ERRORCHECK_NP)
-	      {
-		THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
-		return EDEADLK;
-	      }
-
-	    if (kind == PTHREAD_MUTEX_RECURSIVE_NP)
-	      {
-		THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
-
-		/* Just bump the counter.  */
-		if (__builtin_expect (mutex->__data.__count + 1 == 0, 0))
-		  /* Overflow of the counter.  */
-		  return EAGAIN;
-
-		++mutex->__data.__count;
-
-		return 0;
-	      }
-	  }
-
-	int newval = id;
-#ifdef NO_INCR
-	newval |= FUTEX_WAITERS;
-#endif
-	oldval = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock,
-						      newval, 0);
-
-	if (oldval != 0)
-	  {
-	    /* The mutex is locked.  The kernel will now take care of
-	       everything.  */
-	    INTERNAL_SYSCALL_DECL (__err);
-	    int e = INTERNAL_SYSCALL (futex, __err, 4, &mutex->__data.__lock,
-				      FUTEX_LOCK_PI, 1, 0);
-
-	    if (INTERNAL_SYSCALL_ERROR_P (e, __err)
-		&& (INTERNAL_SYSCALL_ERRNO (e, __err) == ESRCH
-		    || INTERNAL_SYSCALL_ERRNO (e, __err) == EDEADLK))
-	      {
-		assert (INTERNAL_SYSCALL_ERRNO (e, __err) != EDEADLK
-			|| (kind != PTHREAD_MUTEX_ERRORCHECK_NP
-			    && kind != PTHREAD_MUTEX_RECURSIVE_NP));
-		/* ESRCH can happen only for non-robust PI mutexes where
-		   the owner of the lock died.  */
-		assert (INTERNAL_SYSCALL_ERRNO (e, __err) != ESRCH || !robust);
-
-		/* Delay the thread indefinitely.  */
-		while (1)
-		  pause_not_cancel ();
-	      }
-
-	    oldval = mutex->__data.__lock;
-
-	    assert (robust || (oldval & FUTEX_OWNER_DIED) == 0);
-	  }
-
-	if (__builtin_expect (oldval & FUTEX_OWNER_DIED, 0))
-	  {
-	    atomic_and (&mutex->__data.__lock, ~FUTEX_OWNER_DIED);
-
-	    /* We got the mutex.  */
-	    mutex->__data.__count = 1;
-	    /* But it is inconsistent unless marked otherwise.  */
-	    mutex->__data.__owner = PTHREAD_MUTEX_INCONSISTENT;
-
-	    ENQUEUE_MUTEX_PI (mutex);
-	    THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
-
-	    /* Note that we deliberately exit here.  If we fall
-	       through to the end of the function __nusers would be
-	       incremented which is not correct because the old owner
-	       has to be discounted.  If we are not supposed to
-	       increment __nusers we actually have to decrement it here.  */
-#ifdef NO_INCR
-	    --mutex->__data.__nusers;
-#endif
-
-	    return EOWNERDEAD;
-	  }
-
-	if (robust
-	    && __builtin_expect (mutex->__data.__owner
-				 == PTHREAD_MUTEX_NOTRECOVERABLE, 0))
-	  {
-	    /* This mutex is now not recoverable.  */
-	    mutex->__data.__count = 0;
-
-	    INTERNAL_SYSCALL_DECL (__err);
-	    INTERNAL_SYSCALL (futex, __err, 4, &mutex->__data.__lock,
-			      FUTEX_UNLOCK_PI, 0, 0);
-
-	    THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
-	    return ENOTRECOVERABLE;
-	  }
-
-	mutex->__data.__count = 1;
-	if (robust)
-	  {
-	    ENQUEUE_MUTEX_PI (mutex);
-	    THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
-	  }
-      }
-      break;
-
-    case PTHREAD_MUTEX_PP_RECURSIVE_NP:
-    case PTHREAD_MUTEX_PP_ERRORCHECK_NP:
-    case PTHREAD_MUTEX_PP_NORMAL_NP:
-    case PTHREAD_MUTEX_PP_ADAPTIVE_NP:
-      {
-	int kind = mutex->__data.__kind & PTHREAD_MUTEX_KIND_MASK_NP;
-
-	oldval = mutex->__data.__lock;
-
-	/* Check whether we already hold the mutex.  */
-	if (mutex->__data.__owner == id)
-	  {
-	    if (kind == PTHREAD_MUTEX_ERRORCHECK_NP)
-	      return EDEADLK;
-
-	    if (kind == PTHREAD_MUTEX_RECURSIVE_NP)
-	      {
-		/* Just bump the counter.  */
-		if (__builtin_expect (mutex->__data.__count + 1 == 0, 0))
-		  /* Overflow of the counter.  */
-		  return EAGAIN;
-
-		++mutex->__data.__count;
-
-		return 0;
-	      }
-	  }
-
-	int oldprio = -1, ceilval;
-	do
-	  {
-	    int ceiling = (oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK)
-			  >> PTHREAD_MUTEX_PRIO_CEILING_SHIFT;
-
-	    if (__pthread_current_priority () > ceiling)
-	      {
-		if (oldprio != -1)
-		  __pthread_tpp_change_priority (oldprio, -1);
-		return EINVAL;
-	      }
-
-	    retval = __pthread_tpp_change_priority (oldprio, ceiling);
-	    if (retval)
-	      return retval;
-
-	    ceilval = ceiling << PTHREAD_MUTEX_PRIO_CEILING_SHIFT;
-	    oldprio = ceiling;
-
-	    oldval
-	      = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock,
-#ifdef NO_INCR
-						     ceilval | 2,
-#else
-						     ceilval | 1,
-#endif
-						     ceilval);
-
-	    if (oldval == ceilval)
-	      break;
-
-	    do
-	      {
-		oldval
-		  = atomic_compare_and_exchange_val_acq (&mutex->__data.__lock,
-							 ceilval | 2,
-							 ceilval | 1);
-
-		if ((oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) != ceilval)
-		  break;
-
-		if (oldval != ceilval)
-		  lll_futex_wait (&mutex->__data.__lock, ceilval | 2);
-	      }
-	    while (atomic_compare_and_exchange_val_acq (&mutex->__data.__lock,
-							ceilval | 2, ceilval)
-		   != ceilval);
-	  }
-	while ((oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK) != ceilval);
-
-	assert (mutex->__data.__owner == 0);
-	mutex->__data.__count = 1;
-      }
-      break;
-
-    default:
-      /* Correct code cannot set any other type.  */
-      return EINVAL;
     }
 
   /* Record the ownership.  */
+  assert (mutex->__data.__owner == 0);
   mutex->__data.__owner = id;
 #ifndef NO_INCR
   ++mutex->__data.__nusers;
 #endif
 
-  return retval;
+  return 0;
 }
 #ifndef __pthread_mutex_lock
 strong_alias (__pthread_mutex_lock, pthread_mutex_lock)