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-rwxr-xr-xpkg/atomicbitops/atomic_bitops_arm64.s139
-rwxr-xr-x[-rw-r--r--]pkg/atomicbitops/atomicbitops.go (renamed from pkg/atomicbitops/atomic_bitops.go)31
-rwxr-xr-x[-rw-r--r--]pkg/atomicbitops/atomicbitops_amd64.s (renamed from pkg/atomicbitops/atomic_bitops_amd64.s)38
-rwxr-xr-x[-rw-r--r--]pkg/atomicbitops/atomicbitops_noasm.go (renamed from pkg/atomicbitops/atomic_bitops_common.go)42
4 files changed, 9 insertions, 241 deletions
diff --git a/pkg/atomicbitops/atomic_bitops_arm64.s b/pkg/atomicbitops/atomic_bitops_arm64.s
deleted file mode 100755
index 97f8808c1..000000000
--- a/pkg/atomicbitops/atomic_bitops_arm64.s
+++ /dev/null
@@ -1,139 +0,0 @@
-// Copyright 2019 The gVisor Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build arm64
-
-#include "textflag.h"
-
-TEXT ·AndUint32(SB),$0-12
- MOVD ptr+0(FP), R0
- MOVW val+8(FP), R1
-again:
- LDAXRW (R0), R2
- ANDW R1, R2
- STLXRW R2, (R0), R3
- CBNZ R3, again
- RET
-
-TEXT ·OrUint32(SB),$0-12
- MOVD ptr+0(FP), R0
- MOVW val+8(FP), R1
-again:
- LDAXRW (R0), R2
- ORRW R1, R2
- STLXRW R2, (R0), R3
- CBNZ R3, again
- RET
-
-TEXT ·XorUint32(SB),$0-12
- MOVD ptr+0(FP), R0
- MOVW val+8(FP), R1
-again:
- LDAXRW (R0), R2
- EORW R1, R2
- STLXRW R2, (R0), R3
- CBNZ R3, again
- RET
-
-TEXT ·CompareAndSwapUint32(SB),$0-20
- MOVD addr+0(FP), R0
- MOVW old+8(FP), R1
- MOVW new+12(FP), R2
-
-again:
- LDAXRW (R0), R3
- CMPW R1, R3
- BNE done
- STLXRW R2, (R0), R4
- CBNZ R4, again
-done:
- MOVW R3, prev+16(FP)
- RET
-
-TEXT ·AndUint64(SB),$0-16
- MOVD ptr+0(FP), R0
- MOVD val+8(FP), R1
-again:
- LDAXR (R0), R2
- AND R1, R2
- STLXR R2, (R0), R3
- CBNZ R3, again
- RET
-
-TEXT ·OrUint64(SB),$0-16
- MOVD ptr+0(FP), R0
- MOVD val+8(FP), R1
-again:
- LDAXR (R0), R2
- ORR R1, R2
- STLXR R2, (R0), R3
- CBNZ R3, again
- RET
-
-TEXT ·XorUint64(SB),$0-16
- MOVD ptr+0(FP), R0
- MOVD val+8(FP), R1
-again:
- LDAXR (R0), R2
- EOR R1, R2
- STLXR R2, (R0), R3
- CBNZ R3, again
- RET
-
-TEXT ·CompareAndSwapUint64(SB),$0-32
- MOVD addr+0(FP), R0
- MOVD old+8(FP), R1
- MOVD new+16(FP), R2
-
-again:
- LDAXR (R0), R3
- CMP R1, R3
- BNE done
- STLXR R2, (R0), R4
- CBNZ R4, again
-done:
- MOVD R3, prev+24(FP)
- RET
-
-TEXT ·IncUnlessZeroInt32(SB),NOSPLIT,$0-9
- MOVD addr+0(FP), R0
-
-again:
- LDAXRW (R0), R1
- CBZ R1, fail
- ADDW $1, R1
- STLXRW R1, (R0), R2
- CBNZ R2, again
- MOVW $1, R2
- MOVB R2, ret+8(FP)
- RET
-fail:
- MOVB ZR, ret+8(FP)
- RET
-
-TEXT ·DecUnlessOneInt32(SB),NOSPLIT,$0-9
- MOVD addr+0(FP), R0
-
-again:
- LDAXRW (R0), R1
- SUBSW $1, R1, R1
- BEQ fail
- STLXRW R1, (R0), R2
- CBNZ R2, again
- MOVW $1, R2
- MOVB R2, ret+8(FP)
- RET
-fail:
- MOVB ZR, ret+8(FP)
- RET
diff --git a/pkg/atomicbitops/atomic_bitops.go b/pkg/atomicbitops/atomicbitops.go
index fcc41a9ea..1be081719 100644..100755
--- a/pkg/atomicbitops/atomic_bitops.go
+++ b/pkg/atomicbitops/atomicbitops.go
@@ -14,47 +14,34 @@
// +build amd64 arm64
-// Package atomicbitops provides basic bitwise operations in an atomic way.
-// The implementation on amd64 leverages the LOCK prefix directly instead of
-// relying on the generic cas primitives, and the arm64 leverages the LDAXR
-// and STLXR pair primitives.
+// Package atomicbitops provides extensions to the sync/atomic package.
//
-// WARNING: the bitwise ops provided in this package doesn't imply any memory
-// ordering. Using them to construct locks must employ proper memory barriers.
+// All read-modify-write operations implemented by this package have
+// acquire-release memory ordering (like sync/atomic).
package atomicbitops
-// AndUint32 atomically applies bitwise and operation to *addr with val.
+// AndUint32 atomically applies bitwise AND operation to *addr with val.
func AndUint32(addr *uint32, val uint32)
-// OrUint32 atomically applies bitwise or operation to *addr with val.
+// OrUint32 atomically applies bitwise OR operation to *addr with val.
func OrUint32(addr *uint32, val uint32)
-// XorUint32 atomically applies bitwise xor operation to *addr with val.
+// XorUint32 atomically applies bitwise XOR operation to *addr with val.
func XorUint32(addr *uint32, val uint32)
// CompareAndSwapUint32 is like sync/atomic.CompareAndSwapUint32, but returns
// the value previously stored at addr.
func CompareAndSwapUint32(addr *uint32, old, new uint32) uint32
-// AndUint64 atomically applies bitwise and operation to *addr with val.
+// AndUint64 atomically applies bitwise AND operation to *addr with val.
func AndUint64(addr *uint64, val uint64)
-// OrUint64 atomically applies bitwise or operation to *addr with val.
+// OrUint64 atomically applies bitwise OR operation to *addr with val.
func OrUint64(addr *uint64, val uint64)
-// XorUint64 atomically applies bitwise xor operation to *addr with val.
+// XorUint64 atomically applies bitwise XOR operation to *addr with val.
func XorUint64(addr *uint64, val uint64)
// CompareAndSwapUint64 is like sync/atomic.CompareAndSwapUint64, but returns
// the value previously stored at addr.
func CompareAndSwapUint64(addr *uint64, old, new uint64) uint64
-
-// IncUnlessZeroInt32 increments the value stored at the given address and
-// returns true; unless the value stored in the pointer is zero, in which case
-// it is left unmodified and false is returned.
-func IncUnlessZeroInt32(addr *int32) bool
-
-// DecUnlessOneInt32 decrements the value stored at the given address and
-// returns true; unless the value stored in the pointer is 1, in which case it
-// is left unmodified and false is returned.
-func DecUnlessOneInt32(addr *int32) bool
diff --git a/pkg/atomicbitops/atomic_bitops_amd64.s b/pkg/atomicbitops/atomicbitops_amd64.s
index db0972001..54c887ee5 100644..100755
--- a/pkg/atomicbitops/atomic_bitops_amd64.s
+++ b/pkg/atomicbitops/atomicbitops_amd64.s
@@ -75,41 +75,3 @@ TEXT ·CompareAndSwapUint64(SB),$0-32
CMPXCHGQ DX, 0(DI)
MOVQ AX, ret+24(FP)
RET
-
-TEXT ·IncUnlessZeroInt32(SB),NOSPLIT,$0-9
- MOVQ addr+0(FP), DI
- MOVL 0(DI), AX
-
-retry:
- TESTL AX, AX
- JZ fail
- LEAL 1(AX), DX
- LOCK
- CMPXCHGL DX, 0(DI)
- JNZ retry
-
- SETEQ ret+8(FP)
- RET
-
-fail:
- MOVB AX, ret+8(FP)
- RET
-
-TEXT ·DecUnlessOneInt32(SB),NOSPLIT,$0-9
- MOVQ addr+0(FP), DI
- MOVL 0(DI), AX
-
-retry:
- LEAL -1(AX), DX
- TESTL DX, DX
- JZ fail
- LOCK
- CMPXCHGL DX, 0(DI)
- JNZ retry
-
- SETEQ ret+8(FP)
- RET
-
-fail:
- MOVB DX, ret+8(FP)
- RET
diff --git a/pkg/atomicbitops/atomic_bitops_common.go b/pkg/atomicbitops/atomicbitops_noasm.go
index 85163ad62..3b2898256 100644..100755
--- a/pkg/atomicbitops/atomic_bitops_common.go
+++ b/pkg/atomicbitops/atomicbitops_noasm.go
@@ -20,7 +20,6 @@ import (
"sync/atomic"
)
-// AndUint32 atomically applies bitwise and operation to *addr with val.
func AndUint32(addr *uint32, val uint32) {
for {
o := atomic.LoadUint32(addr)
@@ -31,7 +30,6 @@ func AndUint32(addr *uint32, val uint32) {
}
}
-// OrUint32 atomically applies bitwise or operation to *addr with val.
func OrUint32(addr *uint32, val uint32) {
for {
o := atomic.LoadUint32(addr)
@@ -42,7 +40,6 @@ func OrUint32(addr *uint32, val uint32) {
}
}
-// XorUint32 atomically applies bitwise xor operation to *addr with val.
func XorUint32(addr *uint32, val uint32) {
for {
o := atomic.LoadUint32(addr)
@@ -53,8 +50,6 @@ func XorUint32(addr *uint32, val uint32) {
}
}
-// CompareAndSwapUint32 is like sync/atomic.CompareAndSwapUint32, but returns
-// the value previously stored at addr.
func CompareAndSwapUint32(addr *uint32, old, new uint32) (prev uint32) {
for {
prev = atomic.LoadUint32(addr)
@@ -67,7 +62,6 @@ func CompareAndSwapUint32(addr *uint32, old, new uint32) (prev uint32) {
}
}
-// AndUint64 atomically applies bitwise and operation to *addr with val.
func AndUint64(addr *uint64, val uint64) {
for {
o := atomic.LoadUint64(addr)
@@ -78,7 +72,6 @@ func AndUint64(addr *uint64, val uint64) {
}
}
-// OrUint64 atomically applies bitwise or operation to *addr with val.
func OrUint64(addr *uint64, val uint64) {
for {
o := atomic.LoadUint64(addr)
@@ -89,7 +82,6 @@ func OrUint64(addr *uint64, val uint64) {
}
}
-// XorUint64 atomically applies bitwise xor operation to *addr with val.
func XorUint64(addr *uint64, val uint64) {
for {
o := atomic.LoadUint64(addr)
@@ -100,8 +92,6 @@ func XorUint64(addr *uint64, val uint64) {
}
}
-// CompareAndSwapUint64 is like sync/atomic.CompareAndSwapUint64, but returns
-// the value previously stored at addr.
func CompareAndSwapUint64(addr *uint64, old, new uint64) (prev uint64) {
for {
prev = atomic.LoadUint64(addr)
@@ -113,35 +103,3 @@ func CompareAndSwapUint64(addr *uint64, old, new uint64) (prev uint64) {
}
}
}
-
-// IncUnlessZeroInt32 increments the value stored at the given address and
-// returns true; unless the value stored in the pointer is zero, in which case
-// it is left unmodified and false is returned.
-func IncUnlessZeroInt32(addr *int32) bool {
- for {
- v := atomic.LoadInt32(addr)
- if v == 0 {
- return false
- }
-
- if atomic.CompareAndSwapInt32(addr, v, v+1) {
- return true
- }
- }
-}
-
-// DecUnlessOneInt32 decrements the value stored at the given address and
-// returns true; unless the value stored in the pointer is 1, in which case it
-// is left unmodified and false is returned.
-func DecUnlessOneInt32(addr *int32) bool {
- for {
- v := atomic.LoadInt32(addr)
- if v == 1 {
- return false
- }
-
- if atomic.CompareAndSwapInt32(addr, v, v-1) {
- return true
- }
- }
-}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-13 02:50:16 +0000