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authorWaldemar Brodkorb <wbx@uclibc-ng.org>2018-01-01 13:39:41 +0100
committerWaldemar Brodkorb <wbx@uclibc-ng.org>2018-01-15 20:01:31 +0000
commit91daab6288ab3b2b0571c84ba94e029e7e7308dc (patch)
treed536f7dcc8844839a30d6aac0858f2d0bf42738e /libpthread/nptl/sysdeps/generic/lowlevellock.h
parentc47a0379237ddb9260c5a72d6a2318b766b3261d (diff)
nptl: use generic lowlevellock.h for most architectures
Only mips/x86/x86_64 needs a special version of lowlevellock.h. No regressions found.
Diffstat (limited to 'libpthread/nptl/sysdeps/generic/lowlevellock.h')
-rw-r--r--libpthread/nptl/sysdeps/generic/lowlevellock.h83
1 files changed, 0 insertions, 83 deletions
diff --git a/libpthread/nptl/sysdeps/generic/lowlevellock.h b/libpthread/nptl/sysdeps/generic/lowlevellock.h
deleted file mode 100644
index cced770d2..000000000
--- a/libpthread/nptl/sysdeps/generic/lowlevellock.h
+++ /dev/null
@@ -1,83 +0,0 @@
-/* Low level locking macros used in NPTL implementation. Stub version.
- Copyright (C) 2002, 2007 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, see
- <http://www.gnu.org/licenses/>. */
-
-#include <atomic.h>
-
-
-/* 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,
- // XYZ check mutex flag
- LLL_SHARED);
- }
-}
-
-
-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 (mutex, 0x80000000))
- return;
-
- /* There are other threads waiting for this mutex, wake one of them
- up. */
- lll_futex_wake (mutex, 1,
- // XYZ check mutex flag
- LLL_SHARED);
-}
-
-
-#define lll_mutex_lock(futex) __generic_mutex_lock (&(futex))
-#define lll_mutex_unlock(futex) __generic_mutex_unlock (&(futex))