See LICENSE for details.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Mathieu Desnoyers
May 10, 2009
+
+* LGPLv2.1
+
The library part is distributed under LGPLv2.1 or later. See lgpl-2.1.txt for
details. This applies to :
defined. It permits relinking with newer versions of the library, which is
required by the LGPL license.
+
+* MIT-style license :
+
+xchg() privimitive has been rewritten from scratch starting from atomic_ops 1.2
+which has a MIT-style license that is intended to allow use in both free and
+proprietary software:
+ http://www.hpl.hp.com/research/linux/atomic_ops/LICENSING.txt
+ http://www.hpl.hp.com/personal/Hans_Boehm/gc/gc_source/
+
+This license applies to :
+
+arch_atomic_x86.h
+arch_atomic_ppc.h
+
+
+* GPLv2
+
Library test code is distributed under the GPLv2 license. See gpl-2.0.txt for
details. This applies to :
test_urcu_yield.c
test_rwlock_timing.c
urcu-asm.c
+
+
+Various details :
+
+ACCESS_ONCE(), likely(), unlikely() and barrier() are considered trivial enough
+that copyright does not apply to them. I (Mathieu Desnoyers) re-typed them from
+scratch in a mail client just to prove it.
pthreads-x86: clean
cp api_x86.h api.h
cp arch_x86.h arch.h
+ cp arch_atomic_x86.h arch_atomic.h
pthreads-ppc: clean
cp api_ppc.h api.h
cp arch_ppc.h arch.h
+ cp arch_atomic_ppc.h arch_atomic.h
test_urcu: urcu.o test_urcu.c urcu.h
$(CC) ${CFLAGS} $(LDFLAGS) -o $@ $(SRC_DEP)
install: liburcu.so
cp -f liburcu.so /usr/lib/
- cp -f arch.h compiler.h urcu.h urcu-static.h /usr/include/
+ cp -f arch.h arch_atomic.h compiler.h urcu.h urcu-static.h /usr/include/
clean:
rm -f *.o test_urcu test_urcu_timing test_rwlock_timing urcu-asm.S \
test_urcu_yield urcutorture urcutorture-yield liburcu.so \
- test_urcu_dynamic_link api.h arch.h
+ test_urcu_dynamic_link api.h arch.h arch_atomic.h
--- /dev/null
+#ifndef _ARCH_ATOMIC_PPC_H
+#define _ARCH_ATOMIC_PPC_H
+
+/*
+ * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
+ * Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved.
+ * Copyright (c) 1999-2004 Hewlett-Packard Development Company, L.P.
+ * Copyright (c) 2009 Mathieu Desnoyers
+ *
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program
+ * for any purpose, provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is granted,
+ * provided the above notices are retained, and a notice that the code was
+ * modified is included with the above copyright notice.
+ *
+ * Code inspired from libatomic_ops-1.2, inherited in part from the
+ * Boehm-Demers-Weiser conservative garbage collector.
+ */
+
+#ifndef BITS_PER_LONG
+#define BITS_PER_LONG (__SIZEOF_LONG__ * 8)
+#endif
+
+#define ILLEGAL_INSTR .long 0xd00d00
+
+#ifndef _INCLUDE_API_H
+
+/*
+ * Using a isync as second barrier for exchange to provide acquire semantic.
+ * According to atomic_ops/sysdeps/gcc/powerpc.h, the documentation is "fairly
+ * explicit that this also has acquire semantics."
+ * Derived from AO_compare_and_swap(), but removed the comparison.
+ */
+
+static __attribute__((always_inline))
+unsigned int atomic_exchange_32(volatile unsigned int *addr, unsigned int val)
+{
+ unsigned int result;
+
+ __asm__ __volatile__(
+ "lwsync\n"
+ "1:\t" "lwarx %0,0,%1\n" /* load and reserve */
+ "stwcx. %2,0,%1\n" /* else store conditional */
+ "bne- 1b\n" /* retry if lost reservation */
+ "isync\n"
+ : "=&r"(result),
+ : "r"(addr), "r"(val)
+ : "memory", "cc");
+
+ return result;
+}
+
+#if (BITS_PER_LONG == 64)
+
+static __attribute__((always_inline))
+unsigned long atomic_exchange_64(volatile unsigned long *addr,
+ unsigned long val)
+{
+ unsigned long result;
+
+ __asm__ __volatile__(
+ "lwsync\n"
+ "1:\t" "ldarx %0,0,%1\n" /* load and reserve */
+ "stdcx. %2,0,%1\n" /* else store conditional */
+ "bne- 1b\n" /* retry if lost reservation */
+ "isync\n"
+ : "=&r"(result),
+ : "r"(addr), "r"(val)
+ : "memory", "cc");
+
+ return result;
+}
+
+#endif
+
+static __attribute__((always_inline))
+unsigned long _atomic_exchange(volatile void *addr, unsigned long val, int len)
+{
+ switch (len) {
+ case 4: return atomic_exchange_32(addr, val);
+#if (BITS_PER_LONG == 64)
+ case 8: return atomic_exchange_64(addr, val);
+#endif
+ }
+ /* generate an illegal instruction. Cannot catch this with linker tricks
+ * when optimizations are disabled. */
+ __asm__ __volatile__(ILLEGAL_INSTR);
+ return 0;
+}
+
+#define xchg(addr, v) (__typeof__(*(addr)) _atomic_exchange((addr), (v), \
+ sizeof(*(addr))))
+
+#endif /* #ifndef _INCLUDE_API_H */
+
+#endif /* ARCH_ATOMIC_PPC_H */
--- /dev/null
+#ifndef _ARCH_ATOMIC_X86_H
+#define _ARCH_ATOMIC_X86_H
+
+/*
+ * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
+ * Copyright (c) 1996-1999 by Silicon Graphics. All rights reserved.
+ * Copyright (c) 1999-2004 Hewlett-Packard Development Company, L.P.
+ * Copyright (c) 2009 Mathieu Desnoyers
+ *
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program
+ * for any purpose, provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is granted,
+ * provided the above notices are retained, and a notice that the code was
+ * modified is included with the above copyright notice.
+ *
+ * Code inspired from libatomic_ops-1.2, inherited in part from the
+ * Boehm-Demers-Weiser conservative garbage collector.
+ */
+
+#ifndef BITS_PER_LONG
+#define BITS_PER_LONG (__SIZEOF_LONG__ * 8)
+#endif
+
+#ifndef _INCLUDE_API_H
+
+/*
+ * Using a isync as second barrier for exchange to provide acquire semantic.
+ * According to atomic_ops/sysdeps/gcc/powerpc.h, the documentation is "fairly
+ * explicit that this also has acquire semantics."
+ * Derived from AO_compare_and_swap() and AO_test_and_set_full().
+ */
+
+static __attribute__((always_inline))
+unsigned int atomic_exchange_32(volatile unsigned int *addr, unsigned int val)
+{
+ unsigned int result;
+
+ __asm__ __volatile__(
+ /* Note: the "xchg" instruction does not need a "lock" prefix */
+ "xchgl %0, %1"
+ : "=&r"(result), "=m"(*addr)
+ : "0" (val), "m"(*addr)
+ : "memory");
+
+ return result;
+}
+
+#if (BITS_PER_LONG == 64)
+
+static __attribute__((always_inline))
+unsigned long atomic_exchange_64(volatile unsigned long *addr,
+ unsigned long val)
+{
+ unsigned long result;
+
+ __asm__ __volatile__(
+ /* Note: the "xchg" instruction does not need a "lock" prefix */
+ "xchgq %0, %1"
+ : "=&r"(result), "=m"(*addr)
+ : "0" (val), "m"(*addr)
+ : "memory");
+
+ return result;
+}
+
+#endif
+
+static __attribute__((always_inline))
+unsigned long _atomic_exchange(volatile void *addr, unsigned long val, int len)
+{
+ switch (len) {
+ case 4: return atomic_exchange_32(addr, val);
+#if (BITS_PER_LONG == 64)
+ case 8: return atomic_exchange_64(addr, val);
+#endif
+ }
+ /* generate an illegal instruction. Cannot catch this with linker tricks
+ * when optimizations are disabled. */
+ __asm__ __volatile__("ud2");
+ return 0;
+}
+
+#define xchg(addr, v) \
+ ((__typeof__(*(addr))) _atomic_exchange((addr), (unsigned long)(v), \
+ sizeof(*(addr))))
+
+#endif /* #ifndef _INCLUDE_API_H */
+
+#endif /* ARCH_ATOMIC_X86_H */
*/
#include <compiler.h>
+#include <arch_atomic.h>
#define CONFIG_HAVE_FENCE 1
#define CONFIG_HAVE_MEM_COHERENCY
barrier();
}
-#define PPC405_ERR77(ra,rb)
-#define LWSYNC_ON_SMP "\n\tlwsync\n"
-#define ISYNC_ON_SMP "\n\tisync\n"
-
-struct __xchg_dummy {
- unsigned long a[100];
-};
-#define __xg(x) ((struct __xchg_dummy *)(x))
-
-#ifndef _INCLUDE_API_H
-
-/*
- * Exchange the 32-bits value pointed to by p, returns the old value.
- * Might not work with PPC405 (see err 77).
- */
-static __always_inline
-unsigned int __xchg_u32(volatile void *p, unsigned int val)
-{
- unsigned int prev;
-
- __asm__ __volatile__(LWSYNC_ON_SMP
- "1:\t" "lwarx %0,0,%2\n"
- "stwcx. %3,0,%2\n"
- "bne- 1b"
- ISYNC_ON_SMP
- : "=&r" (prev), "+m" (*(volatile unsigned int *)p)
- : "r" (p), "r" (val)
- : "cc", "memory");
- return prev;
-}
-
-#if (BITS_PER_LONG == 64)
-/*
- * Exchange the 64-bits value pointed to by p, returns the old value.
- * Might not work with PPC405 (see err 77).
- */
-static __always_inline
-unsigned long __xchg_u64(volatile void *p, unsigned long val)
-{
- unsigned long prev;
-
- __asm__ __volatile__(LWSYNC_ON_SMP
- "1:\t" "ldarx %0,0,%2\n"
- "stdcx. %3,0,%2\n"
- "bne- 1b"
- ISYNC_ON_SMP
- : "=&r" (prev), "+m" (*(volatile unsigned long *)p)
- : "r" (p), "r" (val)
- : "cc", "memory");
- return prev;
-}
-#endif
-
-static __always_inline
-unsigned long __xchg(volatile void *ptr, unsigned long x, int size)
-{
- switch (size) {
- case 4:
- return __xchg_u32(ptr, x);
-#if (BITS_PER_LONG == 64)
- case 8:
- return __xchg_u64(ptr, x);
-#endif
- }
- return x;
-}
-
-/*
- * note : xchg should only be used with pointers to 32 or 64-bits elements.
- * No build-time check is done on the element size because depending on
- * non-referenced unexisting symbol at link time to provide an error message
- * only work when compiling with optimizations.
- */
-#define xchg(ptr, v) \
- ((__typeof__(*(ptr)))__xchg((ptr), (unsigned long)(v), sizeof(*(ptr))))
-
-#endif /* #ifndef _INCLUDE_API_H */
-
#define mftbl() \
({ \
unsigned long rval; \
*/
#include <compiler.h>
+#include <arch_atomic.h>
/* Assume P4 or newer */
#define CONFIG_HAVE_FENCE 1
rep_nop();
}
-#define xchg(ptr, v) \
- ((__typeof__(*(ptr)))__xchg((ptr), (unsigned long)(v), sizeof(*(ptr))))
-
-struct __xchg_ptr_as_array {
- unsigned long a[100];
-};
-
-#define __xchg_ptr_as_array(x) ((struct __xchg_ptr_as_array *)(x))
-
-/*
- * xchg always implies a "lock" prefix, even on UP. See Intel documentation.
- * volatile attribute is neccessary due to xchg side effect.
- * *ptr is an output argument.
- * x is considered local, ptr is considered remote.
- */
-static inline unsigned long __xchg(volatile void *ptr, unsigned long x,
- int size)
-{
- switch (size) {
- case 1:
- asm volatile("xchgb %b0,%1"
- : "=q" (x)
- : "m" (*__xchg_ptr_as_array(ptr)), "0" (x)
- : "memory");
- break;
- case 2:
- asm volatile("xchgw %w0,%1"
- : "=r" (x)
- : "m" (*__xchg_ptr_as_array(ptr)), "0" (x)
- : "memory");
- break;
- case 4:
- asm volatile("xchgl %k0,%1"
- : "=r" (x)
- : "m" (*__xchg_ptr_as_array(ptr)), "0" (x)
- : "memory");
- break;
-#if (BITS_PER_LONG == 64)
- case 8:
- asm volatile("xchgq %0,%1"
- : "=r" (x)
- : "m" (*__xchg_ptr_as_array(ptr)), "0" (x)
- : "memory");
- break;
-#endif
- }
- smp_wmc();
- return x;
-}
-
#define rdtscll(val) \
do { \
unsigned int __a, __d; \
projects / userspace-rcu.git / commitdiff
