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-rw-r--r--lib/libpthread/arch/alpha/alpha/_atomic_lock.S45
-rw-r--r--lib/libpthread/arch/i386/i386/_atomic_lock.S42
2 files changed, 87 insertions, 0 deletions
diff --git a/lib/libpthread/arch/alpha/alpha/_atomic_lock.S b/lib/libpthread/arch/alpha/alpha/_atomic_lock.S
new file mode 100644
index 0000000..1cfb52f
--- /dev/null
+++ b/lib/libpthread/arch/alpha/alpha/_atomic_lock.S
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 1998 John Birrell <jb@cimlogic.com.au>.
+ * All rights reserved.
+ * copyright Douglas Santry 1996
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the above copyright is retained
+ * in the source form.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Douglas Santry AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL Douglas Santry OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ *
+ */
+
+#include "SYS.h"
+
+/*
+ * Atomicly lock a location with an identifier provided the location
+ * is not currently locked.
+ *
+ * long _atomic_lock(long *);
+ * v0 will contain the return value (zero if lock obtained).
+ */
+LEAF(_atomic_lock,0)
+ LDGP(pv)
+
+0: ldq_l v0, 0(a0) /* read existing lock value */
+ mov 1, t0 /* locked value to store */
+ stq_c t0, 0(a0) /* attempt to store, status in t0 */
+ beq t0, 1f /* branch foward to optimise prediction */
+ mb /* sync with other processors */
+ RET /* return with v0==0 if lock obtained */
+1: br 0b /* loop to try again */
+END(_atomic_lock)
diff --git a/lib/libpthread/arch/i386/i386/_atomic_lock.S b/lib/libpthread/arch/i386/i386/_atomic_lock.S
new file mode 100644
index 0000000..af49aff
--- /dev/null
+++ b/lib/libpthread/arch/i386/i386/_atomic_lock.S
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>.
+ * All rights reserved.
+ * copyright Douglas Santry 1996
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the above copyright is retained
+ * in the source form.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Douglas Santry AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL Douglas Santry OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if defined(LIBC_RCS) && !defined(lint)
+ .text
+ .asciz "$FreeBSD$"
+#endif /* LIBC_RCS and not lint */
+
+#include <machine/asm.h>
+
+/*
+ * Atomicly lock a location with an identifier provided the location
+ * is not currently locked.
+ *
+ * long _atomic_lock(long *);
+ * eax will contain the return value (zero if lock obtained).
+ */
+ENTRY(_atomic_lock)
+ movl 4(%esp), %ecx
+ movl $1, %eax
+ xchg %eax, (%ecx)
+ ret
+
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