diff options
Diffstat (limited to 'sysdeps/tile/nptl/pthread_spin_lock.c')
-rw-r--r-- | sysdeps/tile/nptl/pthread_spin_lock.c | 56 |
1 files changed, 0 insertions, 56 deletions
diff --git a/sysdeps/tile/nptl/pthread_spin_lock.c b/sysdeps/tile/nptl/pthread_spin_lock.c deleted file mode 100644 index a88a302f86..0000000000 --- a/sysdeps/tile/nptl/pthread_spin_lock.c +++ /dev/null @@ -1,56 +0,0 @@ -/* Copyright (C) 2011-2016 Free Software Foundation, Inc. - This file is part of the GNU C Library. - Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011. - - 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 "pthreadP.h" -#include <arch/spr_def.h> -#include <atomic.h> - -/* Bound point for bounded exponential backoff */ -#define BACKOFF_MAX 2048 - -/* Initial cycle delay for exponential backoff */ -#define BACKOFF_START 32 - -#ifdef __tilegx__ -/* Use cmpexch() after the initial fast-path exch to avoid - invalidating the cache line of the lock holder. */ -# define TNS(p) atomic_exchange_acq((p), 1) -# define CMPTNS(p) atomic_compare_and_exchange_val_acq((p), 1, 0) -#else -# define TNS(p) __insn_tns(p) -# define CMPTNS(p) __insn_tns(p) -# define SPR_CYCLE SPR_CYCLE_LOW /* The low 32 bits are sufficient. */ -#endif - -int -pthread_spin_lock (pthread_spinlock_t *lock) -{ - if (__builtin_expect (TNS (lock) != 0, 0)) - { - unsigned int backoff = BACKOFF_START; - while (CMPTNS (lock) != 0) - { - unsigned int start = __insn_mfspr (SPR_CYCLE); - while (__insn_mfspr (SPR_CYCLE) - start < backoff) - ; - if (backoff < BACKOFF_MAX) - backoff *= 2; - } - } - return 0; -} |