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Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c')
-rw-r--r--nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c71
1 files changed, 0 insertions, 71 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c b/nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c
deleted file mode 100644
index a478ac18e3..0000000000
--- a/nptl/sysdeps/unix/sysv/linux/x86/elision-trylock.c
+++ /dev/null
@@ -1,71 +0,0 @@
-/* elision-trylock.c: Lock eliding trylock for pthreads.
- Copyright (C) 2013-2014 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
-
- 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 <pthread.h>
-#include <pthreadP.h>
-#include <lowlevellock.h>
-#include "hle.h"
-#include <elision-conf.h>
-
-#define aconf __elision_aconf
-
-/* Try to elide a futex trylock. FUTEX is the futex variable. ADAPT_COUNT is
- the adaptation counter in the mutex. */
-
-int
-__lll_trylock_elision (int *futex, short *adapt_count)
-{
- /* Implement POSIX semantics by forbiding nesting
- trylock. Sorry. After the abort the code is re-executed
- non transactional and if the lock was already locked
- return an error. */
- _xabort (_ABORT_NESTED_TRYLOCK);
-
- /* Only try a transaction if it's worth it. */
- if (*adapt_count <= 0)
- {
- unsigned status;
-
- if ((status = _xbegin()) == _XBEGIN_STARTED)
- {
- if (*futex == 0)
- return 0;
-
- /* Lock was busy. Fall back to normal locking.
- Could also _xend here but xabort with 0xff code
- is more visible in the profiler. */
- _xabort (_ABORT_LOCK_BUSY);
- }
-
- if (!(status & _XABORT_RETRY))
- {
- /* Internal abort. No chance for retry. For future
- locks don't try speculation for some time. */
- if (*adapt_count != aconf.skip_trylock_internal_abort)
- *adapt_count = aconf.skip_trylock_internal_abort;
- }
- /* Could do some retries here. */
- }
- else
- {
- /* Lost updates are possible, but harmless. */
- (*adapt_count)--;
- }
-
- return lll_trylock (*futex);
-}