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Diffstat (limited to 'libpthread/linuxthreads/sysdeps/powerpc/pt-machine.h')
-rw-r--r--libpthread/linuxthreads/sysdeps/powerpc/pt-machine.h82
1 files changed, 53 insertions, 29 deletions
diff --git a/libpthread/linuxthreads/sysdeps/powerpc/pt-machine.h b/libpthread/linuxthreads/sysdeps/powerpc/pt-machine.h
index 578369a7f..19b77b7e6 100644
--- a/libpthread/linuxthreads/sysdeps/powerpc/pt-machine.h
+++ b/libpthread/linuxthreads/sysdeps/powerpc/pt-machine.h
@@ -1,19 +1,19 @@
/* Machine-dependent pthreads configuration and inline functions.
powerpc version.
- Copyright (C) 1996, 1997, 1998 Free Software Foundation, Inc.
+ Copyright (C) 1996, 1997, 1998, 2000, 2001, 2002 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 Library General Public License as
- published by the Free Software Foundation; either version 2 of the
+ 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
- Library General Public License for more details.
+ Lesser General Public License for more details.
- You should have received a copy of the GNU Library General Public
+ You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc.,
59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
@@ -21,18 +21,20 @@
/* These routines are from Appendix G of the 'PowerPC 601 RISC Microprocessor
User's Manual', by IBM and Motorola. */
+#ifndef _PT_MACHINE_H
+#define _PT_MACHINE_H 1
+
#ifndef PT_EI
# define PT_EI extern inline
#endif
+extern long int testandset (int *spinlock);
+extern int __compare_and_swap (long int *p, long int oldval, long int newval);
+
/* For multiprocessor systems, we want to ensure all memory accesses
- are completed before we reset a lock. */
-#if 0
-/* on non multiprocessor systems, you can just: */
-#define sync() /* nothing */
-#else
-#define sync() __asm__ __volatile__ ("sync")
-#endif
+ are completed before we reset a lock. On other systems, we still
+ need to make sure that the compiler has flushed everything to memory. */
+#define MEMORY_BARRIER() __asm__ __volatile__ ("sync" : : : "memory")
/* Get some notion of the current stack. Need not be exactly the top
of the stack, just something somewhere in the current frame. */
@@ -40,30 +42,52 @@
register char * stack_pointer __asm__ ("r1");
/* Compare-and-swap for semaphores. */
-/* note that test-and-set(x) is the same as compare-and-swap(x, 0, 1) */
+/* note that test-and-set(x) is the same as !compare-and-swap(x, 0, 1) */
-#define HAS_COMPARE_AND_SWAP
-#if BROKEN_PPC_ASM_CR0
-static
-#else
-PT_EI
-#endif
-int
+#define HAS_COMPARE_AND_SWAP_WITH_RELEASE_SEMANTICS
+#define IMPLEMENT_TAS_WITH_CAS
+
+PT_EI int
__compare_and_swap (long int *p, long int oldval, long int newval)
{
int ret;
- sync();
- __asm__ __volatile__(
- "0: lwarx %0,0,%1 ;"
- " xor. %0,%3,%0;"
- " bne 1f;"
- " stwcx. %2,0,%1;"
- " bne- 0b;"
- "1: "
+ __asm__ __volatile__ (
+ "0: lwarx %0,0,%1 ;"
+ " xor. %0,%3,%0;"
+ " bne 1f;"
+ " stwcx. %2,0,%1;"
+ " bne- 0b;"
+ "1: "
: "=&r"(ret)
: "r"(p), "r"(newval), "r"(oldval)
: "cr0", "memory");
- sync();
+ /* This version of __compare_and_swap is to be used when acquiring
+ a lock, so we don't need to worry about whether other memory
+ operations have completed, but we do need to be sure that any loads
+ after this point really occur after we have acquired the lock. */
+ __asm__ __volatile__ ("isync" : : : "memory");
return ret == 0;
}
+
+PT_EI int
+__compare_and_swap_with_release_semantics (long int *p,
+ long int oldval, long int newval)
+{
+ int ret;
+
+ MEMORY_BARRIER ();
+ __asm__ __volatile__ (
+ "0: lwarx %0,0,%1 ;"
+ " xor. %0,%3,%0;"
+ " bne 1f;"
+ " stwcx. %2,0,%1;"
+ " bne- 0b;"
+ "1: "
+ : "=&r"(ret)
+ : "r"(p), "r"(newval), "r"(oldval)
+ : "cr0", "memory");
+ return ret == 0;
+}
+
+#endif /* pt-machine.h */