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authorJakub Jelinek <jakub@redhat.com>2007-07-12 18:26:36 +0000
committerJakub Jelinek <jakub@redhat.com>2007-07-12 18:26:36 +0000
commit0ecb606cb6cf65de1d9fc8a919bceb4be476c602 (patch)
tree2ea1f8305970753e4a657acb2ccc15ca3eec8e2c /nptl/sysdeps/generic/lowlevellock.h
parent7d58530341304d403a6626d7f7a1913165fe2f32 (diff)
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2.5-18.1
Diffstat (limited to 'nptl/sysdeps/generic/lowlevellock.h')
-rw-r--r--nptl/sysdeps/generic/lowlevellock.h89
1 files changed, 0 insertions, 89 deletions
diff --git a/nptl/sysdeps/generic/lowlevellock.h b/nptl/sysdeps/generic/lowlevellock.h
deleted file mode 100644
index 9cffca83e6..0000000000
--- a/nptl/sysdeps/generic/lowlevellock.h
+++ /dev/null
@@ -1,89 +0,0 @@
-/* Copyright (C) 2002 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   Lesser General Public License for more details.
-
-   You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, write to the Free
-   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
-   02111-1307 USA.  */
-
-#include <atomic.h>
-
-
-/* Implement generic mutex.  Basic futex syscall support is required:
-
-     lll_futex_wait(futex, value) - call sys_futex with FUTEX_WAIT
-				    and third parameter VALUE
-
-     lll_futex_wake(futex, value) - call sys_futex with FUTEX_WAKE
-				    and third parameter VALUE
-*/
-
-
-/* Mutex lock counter:
-   bit 31 clear means unlocked;
-   bit 31 set means locked.
-
-   All code that looks at bit 31 first increases the 'number of
-   interested threads' usage counter, which is in bits 0-30.
-
-   All negative mutex values indicate that the mutex is still locked.  */
-
-
-static inline void
-__generic_mutex_lock (int *mutex)
-{
-  unsigned int v;
-
-  /* Bit 31 was clear, we got the mutex.  (this is the fastpath).  */
-  if (atomic_bit_test_set (mutex, 31) == 0)
-    return;
-
-  atomic_increment (mutex);
-
-  while (1)
-    {
-      if (atomic_bit_test_set (mutex, 31) == 0)
-	{
-	  atomic_decrement (mutex);
-	  return;
-	}
-
-      /* We have to wait now. First make sure the futex value we are
-	 monitoring is truly negative (i.e. locked). */
-      v = *mutex;
-      if (v >= 0)
-	continue;
-
-      lll_futex_wait (mutex, v);
-    }
-}
-
-
-static inline void
-__generic_mutex_unlock (int *mutex)
-{
-  /* Adding 0x80000000 to the counter results in 0 if and only if
-     there are not other interested threads - we can return (this is
-     the fastpath).  */
-  if (atomic_add_zero (0x80000000, mutex))
-    return;
-
-  /* There are other threads waiting for this mutex, wake one of them
-     up.  */
-  lll_futex_wake (mutex, 1);
-}
-
-
-#define lll_mutex_lock(futex) __generic_mutex_lock (&(futex))
-#define lll_mutex_unlock(futex) __generic_mutex_unlock (&(futex))