/*
- * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2015 Apple Computer, Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- *
+ *
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
- *
+ *
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
- *
+ *
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
- *
+ *
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
#include <libkern/OSAtomic.h>
+#include <kern/debug.h>
+#include <machine/atomic.h>
enum {
- false = 0,
- true = 1
+ false = 0,
+ true = 1
};
#ifndef NULL
#define NULL ((void *)0)
#endif
+#define ATOMIC_DEBUG DEBUG
+
+#if ATOMIC_DEBUG
+#define ALIGN_TEST(p, t) do{if((uintptr_t)p&(sizeof(t)-1)) panic("Unaligned atomic pointer %p\n",p);}while(0)
+#else
+#define ALIGN_TEST(p, t) do{}while(0)
+#endif
+
/*
* atomic operations
- * these are _the_ atomic operations, currently cast atop CompareAndSwap,
- * which is implemented in assembler. if we are worried about the cost of
- * this layering (we shouldn't be), then all this stuff could be
- * implemented in assembler, as it is in MacOS8/9
- * (derived from SuperMario/NativeLibs/IO/DriverServices/Synchronization.s,
- * which I wrote for NuKernel in a previous life with a different last name...)
- *
- * native Boolean CompareAndSwap(UInt32 oldValue, UInt32 newValue, UInt32 * oldValuePtr);
- *
- * We've since implemented a few more of these -- OSAddAtomic, OSDequeueAtomic,
- * OSEnqueueAtomic etc -- in assembler, either for speed or correctness. See also the
- * commpage atomic operations, and the platform specific versions.
- * Like standards, there are a lot of atomic ops to choose from!
+ * These are _the_ atomic operations, now implemented via compiler built-ins.
+ * It is expected that this C implementation is a candidate for Link-Time-
+ * Optimization inlining, whereas the assembler implementations they replace
+ * were not.
*/
-#ifndef __ppc__
-
-
-SInt32 OSIncrementAtomic(volatile SInt32 * value)
+#undef OSCompareAndSwap8
+Boolean
+OSCompareAndSwap8(UInt8 oldValue, UInt8 newValue, volatile UInt8 *address)
{
- return OSAddAtomic(1, value);
+ return (Boolean)os_atomic_cmpxchg(address, oldValue, newValue, acq_rel);
}
-SInt32 OSDecrementAtomic(volatile SInt32 * value)
+#undef OSCompareAndSwap16
+Boolean
+OSCompareAndSwap16(UInt16 oldValue, UInt16 newValue, volatile UInt16 *address)
{
- return OSAddAtomic(-1, value);
+ return (Boolean)os_atomic_cmpxchg(address, oldValue, newValue, acq_rel);
}
-#ifdef CMPXCHG8B
-void * OSDequeueAtomic(void * volatile * inList, SInt32 inOffset)
+#undef OSCompareAndSwap
+Boolean
+OSCompareAndSwap(UInt32 oldValue, UInt32 newValue, volatile UInt32 *address)
{
- /* The _pointer_ is volatile, not the listhead itself */
- void * volatile oldListHead;
- void * volatile newListHead;
-
- do {
- oldListHead = *inList;
- if (oldListHead == NULL) {
- break;
- }
-
- newListHead = *(void * volatile *) (((char *) oldListHead) + inOffset);
- } while (! OSCompareAndSwap((UInt32)oldListHead,
- (UInt32)newListHead, (volatile UInt32 *)inList));
- return oldListHead;
+ ALIGN_TEST(address, UInt32);
+ return (Boolean)os_atomic_cmpxchg(address, oldValue, newValue, acq_rel);
}
-void OSEnqueueAtomic(void * volatile * inList, void * inNewLink, SInt32 inOffset)
+#undef OSCompareAndSwap64
+Boolean
+OSCompareAndSwap64(UInt64 oldValue, UInt64 newValue, volatile UInt64 *address)
{
- /* The _pointer_ is volatile, not the listhead itself */
- void * volatile oldListHead;
- void * volatile newListHead = inNewLink;
- void * volatile * newLinkNextPtr = (void * volatile *) (((char *) inNewLink) + inOffset);
-
- do {
- oldListHead = *inList;
- *newLinkNextPtr = oldListHead;
- } while (! OSCompareAndSwap((UInt32)oldListHead, (UInt32)newListHead,
- (volatile UInt32 *)inList));
+ /*
+ * _Atomic uint64 requires 8-byte alignment on all architectures.
+ * This silences the compiler cast warning. ALIGN_TEST() verifies
+ * that the cast was legal, if defined.
+ */
+ _Atomic UInt64 *aligned_addr = (_Atomic UInt64 *)(uintptr_t)address;
+
+ ALIGN_TEST(address, UInt64);
+ return (Boolean)os_atomic_cmpxchg(aligned_addr, oldValue, newValue, acq_rel);
}
-#endif /* CMPXCHG8B */
-#endif /* !__ppc__ */
-static UInt32 OSBitwiseAtomic(UInt32 and_mask, UInt32 or_mask, UInt32 xor_mask, volatile UInt32 * value)
+#undef OSCompareAndSwapPtr
+Boolean
+OSCompareAndSwapPtr(void *oldValue, void *newValue, void * volatile *address)
{
- UInt32 oldValue;
- UInt32 newValue;
-
- do {
- oldValue = *value;
- newValue = ((oldValue & and_mask) | or_mask) ^ xor_mask;
- } while (! OSCompareAndSwap(oldValue, newValue, value));
-
- return oldValue;
+ return (Boolean)os_atomic_cmpxchg(address, oldValue, newValue, acq_rel);
}
-UInt32 OSBitAndAtomic(UInt32 mask, volatile UInt32 * value)
+SInt8
+OSAddAtomic8(SInt32 amount, volatile SInt8 *address)
{
- return OSBitwiseAtomic(mask, 0, 0, value);
+ return os_atomic_add_orig(address, (SInt8)amount, relaxed);
}
-UInt32 OSBitOrAtomic(UInt32 mask, volatile UInt32 * value)
+SInt16
+OSAddAtomic16(SInt32 amount, volatile SInt16 *address)
{
- return OSBitwiseAtomic((UInt32) -1, mask, 0, value);
+ return os_atomic_add_orig(address, (SInt16)amount, relaxed);
}
-UInt32 OSBitXorAtomic(UInt32 mask, volatile UInt32 * value)
+#undef OSAddAtomic
+SInt32
+OSAddAtomic(SInt32 amount, volatile SInt32 *address)
{
- return OSBitwiseAtomic((UInt32) -1, 0, mask, value);
+ ALIGN_TEST(address, UInt32);
+ return os_atomic_add_orig(address, amount, relaxed);
}
-static Boolean OSCompareAndSwap8(UInt8 oldValue8, UInt8 newValue8, volatile UInt8 * value8)
+#undef OSAddAtomic64
+SInt64
+OSAddAtomic64(SInt64 amount, volatile SInt64 *address)
{
- UInt32 mask = 0x000000ff;
- UInt32 alignment = ((UInt32) value8) & (sizeof(UInt32) - 1);
- UInt32 shiftValues = (24 << 24) | (16 << 16) | (8 << 8);
- int shift = (UInt32) *(((UInt8 *) &shiftValues) + alignment);
- volatile UInt32 * value32 = (volatile UInt32 *) (value8 - alignment);
- UInt32 oldValue;
- UInt32 newValue;
+ _Atomic SInt64* aligned_address = (_Atomic SInt64*)(uintptr_t)address;
- mask <<= shift;
-
- oldValue = *value32;
- oldValue = (oldValue & ~mask) | (oldValue8 << shift);
- newValue = (oldValue & ~mask) | (newValue8 << shift);
-
- return OSCompareAndSwap(oldValue, newValue, value32);
+ ALIGN_TEST(address, SInt64);
+ return os_atomic_add_orig(aligned_address, amount, relaxed);
}
-static Boolean OSTestAndSetClear(UInt32 bit, Boolean wantSet, volatile UInt8 * startAddress)
+#undef OSAddAtomicLong
+long
+OSAddAtomicLong(long theAmount, volatile long *address)
{
- UInt8 mask = 1;
- UInt8 oldValue;
- UInt8 wantValue;
-
- startAddress += (bit / 8);
- mask <<= (7 - (bit % 8));
- wantValue = wantSet ? mask : 0;
-
- do {
- oldValue = *startAddress;
- if ((oldValue & mask) == wantValue) {
- break;
- }
- } while (! OSCompareAndSwap8(oldValue, (oldValue & ~mask) | wantValue, startAddress));
-
- return (oldValue & mask) == wantValue;
+ return os_atomic_add_orig(address, theAmount, relaxed);
}
-Boolean OSTestAndSet(UInt32 bit, volatile UInt8 * startAddress)
+#undef OSIncrementAtomic
+SInt32
+OSIncrementAtomic(volatile SInt32 * value)
{
- return OSTestAndSetClear(bit, true, startAddress);
+ return os_atomic_inc_orig(value, relaxed);
}
-Boolean OSTestAndClear(UInt32 bit, volatile UInt8 * startAddress)
+#undef OSDecrementAtomic
+SInt32
+OSDecrementAtomic(volatile SInt32 * value)
{
- return OSTestAndSetClear(bit, false, startAddress);
+ return os_atomic_dec_orig(value, relaxed);
}
-/*
- * silly unaligned versions
- */
-
-SInt8 OSIncrementAtomic8(volatile SInt8 * value)
+#undef OSBitAndAtomic
+UInt32
+OSBitAndAtomic(UInt32 mask, volatile UInt32 * value)
{
- return OSAddAtomic8(1, value);
+ return os_atomic_and_orig(value, mask, relaxed);
}
-SInt8 OSDecrementAtomic8(volatile SInt8 * value)
+#undef OSBitOrAtomic
+UInt32
+OSBitOrAtomic(UInt32 mask, volatile UInt32 * value)
{
- return OSAddAtomic8(-1, value);
+ return os_atomic_or_orig(value, mask, relaxed);
}
-SInt8 OSAddAtomic8(SInt32 amount, volatile SInt8 * value)
+#undef OSBitXorAtomic
+UInt32
+OSBitXorAtomic(UInt32 mask, volatile UInt32 * value)
{
- SInt8 oldValue;
- SInt8 newValue;
-
- do {
- oldValue = *value;
- newValue = oldValue + amount;
- } while (! OSCompareAndSwap8((UInt8) oldValue, (UInt8) newValue, (volatile UInt8 *) value));
-
- return oldValue;
+ return os_atomic_xor_orig(value, mask, relaxed);
}
-static UInt8 OSBitwiseAtomic8(UInt32 and_mask, UInt32 or_mask, UInt32 xor_mask, volatile UInt8 * value)
+static Boolean
+OSTestAndSetClear(UInt32 bit, Boolean wantSet, volatile UInt8 * startAddress)
{
- UInt8 oldValue;
- UInt8 newValue;
-
- do {
- oldValue = *value;
- newValue = ((oldValue & and_mask) | or_mask) ^ xor_mask;
- } while (! OSCompareAndSwap8(oldValue, newValue, value));
-
- return oldValue;
+ UInt8 mask = 1;
+ UInt8 oldValue, newValue;
+ UInt8 wantValue;
+ UInt8 *address;
+
+ address = (UInt8 *)(uintptr_t)(startAddress + (bit / 8));
+ mask <<= (7 - (bit % 8));
+ wantValue = wantSet ? mask : 0;
+
+ return !os_atomic_rmw_loop(address, oldValue, newValue, relaxed, {
+ if ((oldValue & mask) == wantValue) {
+ os_atomic_rmw_loop_give_up(break);
+ }
+ newValue = (oldValue & ~mask) | wantValue;
+ });
}
-UInt8 OSBitAndAtomic8(UInt32 mask, volatile UInt8 * value)
+Boolean
+OSTestAndSet(UInt32 bit, volatile UInt8 * startAddress)
{
- return OSBitwiseAtomic8(mask, 0, 0, value);
+ return OSTestAndSetClear(bit, true, startAddress);
}
-UInt8 OSBitOrAtomic8(UInt32 mask, volatile UInt8 * value)
+Boolean
+OSTestAndClear(UInt32 bit, volatile UInt8 * startAddress)
{
- return OSBitwiseAtomic8((UInt32) -1, mask, 0, value);
+ return OSTestAndSetClear(bit, false, startAddress);
}
-UInt8 OSBitXorAtomic8(UInt32 mask, volatile UInt8 * value)
+/*
+ * silly unaligned versions
+ */
+
+SInt8
+OSIncrementAtomic8(volatile SInt8 * value)
{
- return OSBitwiseAtomic8((UInt32) -1, 0, mask, value);
+ return os_atomic_inc_orig(value, relaxed);
}
-static Boolean OSCompareAndSwap16(UInt16 oldValue16, UInt16 newValue16, volatile UInt16 * value16)
+SInt8
+OSDecrementAtomic8(volatile SInt8 * value)
{
- UInt32 mask = 0x0000ffff;
- UInt32 alignment = ((UInt32) value16) & (sizeof(UInt32) - 1);
- UInt32 shiftValues = (16 << 24) | (16 << 16);
- UInt32 shift = (UInt32) *(((UInt8 *) &shiftValues) + alignment);
- volatile UInt32 * value32 = (volatile UInt32 *) (((UInt32) value16) - alignment);
- UInt32 oldValue;
- UInt32 newValue;
-
- mask <<= shift;
-
- oldValue = *value32;
- oldValue = (oldValue & ~mask) | (oldValue16 << shift);
- newValue = (oldValue & ~mask) | (newValue16 << shift);
-
- return OSCompareAndSwap(oldValue, newValue, value32);
+ return os_atomic_dec_orig(value, relaxed);
}
-SInt16 OSIncrementAtomic16(volatile SInt16 * value)
+UInt8
+OSBitAndAtomic8(UInt32 mask, volatile UInt8 * value)
{
- return OSAddAtomic16(1, value);
+ return os_atomic_and_orig(value, (UInt8)mask, relaxed);
}
-SInt16 OSDecrementAtomic16(volatile SInt16 * value)
+UInt8
+OSBitOrAtomic8(UInt32 mask, volatile UInt8 * value)
{
- return OSAddAtomic16(-1, value);
+ return os_atomic_or_orig(value, (UInt8)mask, relaxed);
}
-SInt16 OSAddAtomic16(SInt32 amount, volatile SInt16 * value)
+UInt8
+OSBitXorAtomic8(UInt32 mask, volatile UInt8 * value)
{
- SInt16 oldValue;
- SInt16 newValue;
-
- do {
- oldValue = *value;
- newValue = oldValue + amount;
- } while (! OSCompareAndSwap16((UInt16) oldValue, (UInt16) newValue, (volatile UInt16 *) value));
-
- return oldValue;
+ return os_atomic_xor_orig(value, (UInt8)mask, relaxed);
}
-static UInt16 OSBitwiseAtomic16(UInt32 and_mask, UInt32 or_mask, UInt32 xor_mask, volatile UInt16 * value)
+SInt16
+OSIncrementAtomic16(volatile SInt16 * value)
{
- UInt16 oldValue;
- UInt16 newValue;
-
- do {
- oldValue = *value;
- newValue = ((oldValue & and_mask) | or_mask) ^ xor_mask;
- } while (! OSCompareAndSwap16(oldValue, newValue, value));
-
- return oldValue;
+ return OSAddAtomic16(1, value);
}
-UInt16 OSBitAndAtomic16(UInt32 mask, volatile UInt16 * value)
+SInt16
+OSDecrementAtomic16(volatile SInt16 * value)
{
- return OSBitwiseAtomic16(mask, 0, 0, value);
+ return OSAddAtomic16(-1, value);
}
-UInt16 OSBitOrAtomic16(UInt32 mask, volatile UInt16 * value)
+UInt16
+OSBitAndAtomic16(UInt32 mask, volatile UInt16 * value)
{
- return OSBitwiseAtomic16((UInt32) -1, mask, 0, value);
+ return os_atomic_and_orig(value, (UInt16)mask, relaxed);
}
-UInt16 OSBitXorAtomic16(UInt32 mask, volatile UInt16 * value)
+UInt16
+OSBitOrAtomic16(UInt32 mask, volatile UInt16 * value)
{
- return OSBitwiseAtomic16((UInt32) -1, 0, mask, value);
+ return os_atomic_or_orig(value, (UInt16)mask, relaxed);
}
+UInt16
+OSBitXorAtomic16(UInt32 mask, volatile UInt16 * value)
+{
+ return os_atomic_xor_orig(value, (UInt16)mask, relaxed);
+}
projects / apple / xnu.git / blobdiff