1 files changed, 256 insertions, 0 deletions
diff --git a/libgomp/config/linux/lock.c b/libgomp/config/linux/lock.c
new file mode 100644
index 000000000..405460780
--- /dev/null
+++ b/libgomp/config/linux/lock.c
@@ -0,0 +1,256 @@
+/* Copyright (C) 2005, 2008, 2009 Free Software Foundation, Inc.
+   Contributed by Richard Henderson <rth@redhat.com>.
+
+   This file is part of the GNU OpenMP Library (libgomp).
+
+   Libgomp is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3, or (at your option)
+   any later version.
+
+   Libgomp 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 General Public License for
+   more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* This is a Linux specific implementation of the public OpenMP locking
+   primitives.  This implementation uses atomic instructions and the futex
+   syscall.  */
+
+#include <string.h>
+#include <unistd.h>
+#include <sys/syscall.h>
+#include "wait.h"
+
+
+/* The internal gomp_mutex_t and the external non-recursive omp_lock_t
+   have the same form.  Re-use it.  */
+
+void
+gomp_init_lock_30 (omp_lock_t *lock)
+{
+  gomp_mutex_init (lock);
+}
+
+void
+gomp_destroy_lock_30 (omp_lock_t *lock)
+{
+  gomp_mutex_destroy (lock);
+}
+
+void
+gomp_set_lock_30 (omp_lock_t *lock)
+{
+  gomp_mutex_lock (lock);
+}
+
+void
+gomp_unset_lock_30 (omp_lock_t *lock)
+{
+  gomp_mutex_unlock (lock);
+}
+
+int
+gomp_test_lock_30 (omp_lock_t *lock)
+{
+  return __sync_bool_compare_and_swap (lock, 0, 1);
+}
+
+void
+gomp_init_nest_lock_30 (omp_nest_lock_t *lock)
+{
+  memset (lock, '\0', sizeof (*lock));
+}
+
+void
+gomp_destroy_nest_lock_30 (omp_nest_lock_t *lock)
+{
+}
+
+void
+gomp_set_nest_lock_30 (omp_nest_lock_t *lock)
+{
+  void *me = gomp_icv (true);
+
+  if (lock->owner != me)
+    {
+      gomp_mutex_lock (&lock->lock);
+      lock->owner = me;
+    }
+
+  lock->count++;
+}
+
+void
+gomp_unset_nest_lock_30 (omp_nest_lock_t *lock)
+{
+  if (--lock->count == 0)
+    {
+      lock->owner = NULL;
+      gomp_mutex_unlock (&lock->lock);
+    }
+}
+
+int
+gomp_test_nest_lock_30 (omp_nest_lock_t *lock)
+{
+  void *me = gomp_icv (true);
+
+  if (lock->owner == me)
+    return ++lock->count;
+
+  if (__sync_bool_compare_and_swap (&lock->lock, 0, 1))
+    {
+      lock->owner = me;
+      lock->count = 1;
+      return 1;
+    }
+
+  return 0;
+}
+
+#ifdef LIBGOMP_GNU_SYMBOL_VERSIONING
+/* gomp_mutex_* can be safely locked in one thread and
+   unlocked in another thread, so the OpenMP 2.5 and OpenMP 3.0
+   non-nested locks can be the same.  */
+strong_alias (gomp_init_lock_30, gomp_init_lock_25)
+strong_alias (gomp_destroy_lock_30, gomp_destroy_lock_25)
+strong_alias (gomp_set_lock_30, gomp_set_lock_25)
+strong_alias (gomp_unset_lock_30, gomp_unset_lock_25)
+strong_alias (gomp_test_lock_30, gomp_test_lock_25)
+
+/* The external recursive omp_nest_lock_25_t form requires additional work.  */
+
+/* We need an integer to uniquely identify this thread.  Most generally
+   this is the thread's TID, which ideally we'd get this straight from
+   the TLS block where glibc keeps it.  Unfortunately, we can't get at
+   that directly.
+
+   If we don't support (or have disabled) TLS, one function call is as
+   good (or bad) as any other.  Use the syscall all the time.
+
+   On an ILP32 system (defined here as not LP64), we can make do with
+   any thread-local pointer.  Ideally we'd use the TLS base address,
+   since that requires the least amount of arithmetic, but that's not
+   always available directly.  Make do with the gomp_thread pointer
+   since it's handy.  */
+
+# if !defined (HAVE_TLS)
+static inline int gomp_tid (void)
+{
+  return syscall (SYS_gettid);
+}
+# elif !defined(__LP64__)
+static inline int gomp_tid (void)
+{
+  return (int) gomp_thread ();
+}
+# else
+static __thread int tid_cache;
+static inline int gomp_tid (void)
+{
+  int tid = tid_cache;
+  if (__builtin_expect (tid == 0, 0))
+    tid_cache = tid = syscall (SYS_gettid);
+  return tid;
+}
+# endif
+
+
+void
+gomp_init_nest_lock_25 (omp_nest_lock_25_t *lock)
+{
+  memset (lock, 0, sizeof (lock));
+}
+
+void
+gomp_destroy_nest_lock_25 (omp_nest_lock_25_t *lock)
+{
+}
+
+void
+gomp_set_nest_lock_25 (omp_nest_lock_25_t *lock)
+{
+  int otid, tid = gomp_tid ();
+
+  while (1)
+    {
+      otid = __sync_val_compare_and_swap (&lock->owner, 0, tid);
+      if (otid == 0)
+	{
+	  lock->count = 1;
+	  return;
+	}
+      if (otid == tid)
+	{
+	  lock->count++;
+	  return;
+	}
+
+      do_wait (&lock->owner, otid);
+    }
+}
+
+void
+gomp_unset_nest_lock_25 (omp_nest_lock_25_t *lock)
+{
+  /* ??? Validate that we own the lock here.  */
+
+  if (--lock->count == 0)
+    {
+      __sync_lock_release (&lock->owner);
+      futex_wake (&lock->owner, 1);
+    }
+}
+
+int
+gomp_test_nest_lock_25 (omp_nest_lock_25_t *lock)
+{
+  int otid, tid = gomp_tid ();
+
+  otid = __sync_val_compare_and_swap (&lock->owner, 0, tid);
+  if (otid == 0)
+    {
+      lock->count = 1;
+      return 1;
+    }
+  if (otid == tid)
+    return ++lock->count;
+
+  return 0;
+}
+
+omp_lock_symver (omp_init_lock)
+omp_lock_symver (omp_destroy_lock)
+omp_lock_symver (omp_set_lock)
+omp_lock_symver (omp_unset_lock)
+omp_lock_symver (omp_test_lock)
+omp_lock_symver (omp_init_nest_lock)
+omp_lock_symver (omp_destroy_nest_lock)
+omp_lock_symver (omp_set_nest_lock)
+omp_lock_symver (omp_unset_nest_lock)
+omp_lock_symver (omp_test_nest_lock)
+
+#else
+
+ialias (omp_init_lock)
+ialias (omp_init_nest_lock)
+ialias (omp_destroy_lock)
+ialias (omp_destroy_nest_lock)
+ialias (omp_set_lock)
+ialias (omp_set_nest_lock)
+ialias (omp_unset_lock)
+ialias (omp_unset_nest_lock)
+ialias (omp_test_lock)
+ialias (omp_test_nest_lock)
+
+#endif