2.5-18.1

1 files changed, 200 insertions, 14 deletions

diff --git a/nptl/pthread_mutex_unlock.c b/nptl/pthread_mutex_unlock.c
index 32bc2a4bc1..33919d60af 100644
--- a/nptl/pthread_mutex_unlock.c
+++ b/nptl/pthread_mutex_unlock.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
+/* Copyright (C) 2002, 2003, 2005, 2006 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
 
@@ -18,6 +18,7 @@
    02111-1307 USA.  */
 
 #include <errno.h>
+#include <stdlib.h>
 #include "pthreadP.h"
 #include <lowlevellock.h>
 
@@ -28,6 +29,8 @@ __pthread_mutex_unlock_usercnt (mutex, decr)
      pthread_mutex_t *mutex;
      int decr;
 {
+  int newowner = 0;
+
   switch (__builtin_expect (mutex->__data.__kind, PTHREAD_MUTEX_TIMED_NP))
     {
     case PTHREAD_MUTEX_RECURSIVE_NP:
@@ -38,31 +41,214 @@ __pthread_mutex_unlock_usercnt (mutex, decr)
       if (--mutex->__data.__count != 0)
 	/* We still hold the mutex.  */
 	return 0;
-      break;
+      goto normal;
 
     case PTHREAD_MUTEX_ERRORCHECK_NP:
       /* Error checking mutex.  */
       if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid)
 	  || ! lll_mutex_islocked (mutex->__data.__lock))
 	return EPERM;
-      break;
+      /* FALLTHROUGH */
 
-    default:
-      /* Correct code cannot set any other type.  */
     case PTHREAD_MUTEX_TIMED_NP:
     case PTHREAD_MUTEX_ADAPTIVE_NP:
-      /* Normal mutex.  Nothing special to do.  */
+      /* Always reset the owner field.  */
+    normal:
+      mutex->__data.__owner = 0;
+      if (decr)
+	/* One less user.  */
+	--mutex->__data.__nusers;
+
+      /* Unlock.  */
+      lll_mutex_unlock (mutex->__data.__lock);
       break;
-    }
 
-  /* Always reset the owner field.  */
-  mutex->__data.__owner = 0;
-  if (decr)
-    /* One less user.  */
-    --mutex->__data.__nusers;
+    case PTHREAD_MUTEX_ROBUST_RECURSIVE_NP:
+      /* Recursive mutex.  */
+      if ((mutex->__data.__lock & FUTEX_TID_MASK)
+	  == THREAD_GETMEM (THREAD_SELF, tid)
+	  && __builtin_expect (mutex->__data.__owner
+			       == PTHREAD_MUTEX_INCONSISTENT, 0))
+	{
+	  if (--mutex->__data.__count != 0)
+	    /* We still hold the mutex.  */
+	    return ENOTRECOVERABLE;
+
+	  goto notrecoverable;
+	}
+
+      if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
+	return EPERM;
+
+      if (--mutex->__data.__count != 0)
+	/* We still hold the mutex.  */
+	return 0;
+
+      goto robust;
+
+    case PTHREAD_MUTEX_ROBUST_ERRORCHECK_NP:
+    case PTHREAD_MUTEX_ROBUST_NORMAL_NP:
+    case PTHREAD_MUTEX_ROBUST_ADAPTIVE_NP:
+      if ((mutex->__data.__lock & FUTEX_TID_MASK)
+	  != THREAD_GETMEM (THREAD_SELF, tid)
+	  || ! lll_mutex_islocked (mutex->__data.__lock))
+	return EPERM;
+
+      /* If the previous owner died and the caller did not succeed in
+	 making the state consistent, mark the mutex as unrecoverable
+	 and make all waiters.  */
+      if (__builtin_expect (mutex->__data.__owner
+			    == PTHREAD_MUTEX_INCONSISTENT, 0))
+      notrecoverable:
+	newowner = PTHREAD_MUTEX_NOTRECOVERABLE;
+
+    robust:
+      /* Remove mutex from the list.  */
+      THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending,
+		     &mutex->__data.__list.__next);
+      DEQUEUE_MUTEX (mutex);
+
+      mutex->__data.__owner = newowner;
+      if (decr)
+	/* One less user.  */
+	--mutex->__data.__nusers;
+
+      /* Unlock.  */
+      lll_robust_mutex_unlock (mutex->__data.__lock);
+
+      THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
+      break;
+
+    case PTHREAD_MUTEX_PI_RECURSIVE_NP:
+      /* Recursive mutex.  */
+      if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
+	return EPERM;
+
+      if (--mutex->__data.__count != 0)
+	/* We still hold the mutex.  */
+	return 0;
+      goto continue_pi;
+
+    case PTHREAD_MUTEX_PI_ROBUST_RECURSIVE_NP:
+      /* Recursive mutex.  */
+      if ((mutex->__data.__lock & FUTEX_TID_MASK)
+	  == THREAD_GETMEM (THREAD_SELF, tid)
+	  && __builtin_expect (mutex->__data.__owner
+			       == PTHREAD_MUTEX_INCONSISTENT, 0))
+	{
+	  if (--mutex->__data.__count != 0)
+	    /* We still hold the mutex.  */
+	    return ENOTRECOVERABLE;
+
+	  goto pi_notrecoverable;
+	}
 
-  /* Unlock.  */
-  lll_mutex_unlock (mutex->__data.__lock);
+      if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
+	return EPERM;
+
+      if (--mutex->__data.__count != 0)
+	/* We still hold the mutex.  */
+	return 0;
+
+      goto continue_pi;
+
+    case PTHREAD_MUTEX_PI_ERRORCHECK_NP:
+    case PTHREAD_MUTEX_PI_NORMAL_NP:
+    case PTHREAD_MUTEX_PI_ADAPTIVE_NP:
+    case PTHREAD_MUTEX_PI_ROBUST_ERRORCHECK_NP:
+    case PTHREAD_MUTEX_PI_ROBUST_NORMAL_NP:
+    case PTHREAD_MUTEX_PI_ROBUST_ADAPTIVE_NP:
+      if ((mutex->__data.__lock & FUTEX_TID_MASK)
+	  != THREAD_GETMEM (THREAD_SELF, tid)
+	  || ! lll_mutex_islocked (mutex->__data.__lock))
+	return EPERM;
+
+      /* If the previous owner died and the caller did not succeed in
+	 making the state consistent, mark the mutex as unrecoverable
+	 and make all waiters.  */
+      if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP) != 0
+	  && __builtin_expect (mutex->__data.__owner
+			       == PTHREAD_MUTEX_INCONSISTENT, 0))
+      pi_notrecoverable:
+       newowner = PTHREAD_MUTEX_NOTRECOVERABLE;
+
+    continue_pi:
+      if ((mutex->__data.__kind & PTHREAD_MUTEX_ROBUST_NORMAL_NP) != 0)
+	{
+	  /* Remove mutex from the list.
+	     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));
+	  DEQUEUE_MUTEX (mutex);
+	}
+
+      mutex->__data.__owner = newowner;
+      if (decr)
+	/* One less user.  */
+	--mutex->__data.__nusers;
+
+      /* Unlock.  */
+      if ((mutex->__data.__lock & FUTEX_WAITERS) != 0
+	  || atomic_compare_and_exchange_bool_acq (&mutex->__data.__lock, 0,
+						   THREAD_GETMEM (THREAD_SELF,
+								  tid)))
+	{
+	  INTERNAL_SYSCALL_DECL (__err);
+	  INTERNAL_SYSCALL (futex, __err, 2, &mutex->__data.__lock,
+			    FUTEX_UNLOCK_PI);
+	}
+
+      THREAD_SETMEM (THREAD_SELF, robust_head.list_op_pending, NULL);
+      break;
+
+    case PTHREAD_MUTEX_PP_RECURSIVE_NP:
+      /* Recursive mutex.  */
+      if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid))
+	return EPERM;
+
+      if (--mutex->__data.__count != 0)
+	/* We still hold the mutex.  */
+	return 0;
+      goto pp;
+
+    case PTHREAD_MUTEX_PP_ERRORCHECK_NP:
+      /* Error checking mutex.  */
+      if (mutex->__data.__owner != THREAD_GETMEM (THREAD_SELF, tid)
+	  || (mutex->__data.__lock & ~ PTHREAD_MUTEX_PRIO_CEILING_MASK) == 0)
+	return EPERM;
+      /* FALLTHROUGH */
+
+    case PTHREAD_MUTEX_PP_NORMAL_NP:
+    case PTHREAD_MUTEX_PP_ADAPTIVE_NP:
+      /* Always reset the owner field.  */
+    pp:
+      mutex->__data.__owner = 0;
+
+      if (decr)
+	/* One less user.  */
+	--mutex->__data.__nusers;
+
+      /* Unlock.  */
+      int newval, oldval;
+      do
+	{
+	  oldval = mutex->__data.__lock;
+	  newval = oldval & PTHREAD_MUTEX_PRIO_CEILING_MASK;
+	}
+      while (atomic_compare_and_exchange_bool_acq (&mutex->__data.__lock,
+						   newval, oldval));
+
+      if ((oldval & ~PTHREAD_MUTEX_PRIO_CEILING_MASK) > 1)
+	lll_futex_wake (&mutex->__data.__lock, 1);
+
+      int oldprio = newval >> PTHREAD_MUTEX_PRIO_CEILING_SHIFT;
+      return __pthread_tpp_change_priority (oldprio, -1);
+
+    default:
+      /* Correct code cannot set any other type.  */
+      return EINVAL;
+    }
 
   return 0;
 }