diff options
Diffstat (limited to 'vendor/google.golang.org/protobuf/internal/impl/bitmap_race.go')
-rw-r--r-- | vendor/google.golang.org/protobuf/internal/impl/bitmap_race.go | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/vendor/google.golang.org/protobuf/internal/impl/bitmap_race.go b/vendor/google.golang.org/protobuf/internal/impl/bitmap_race.go new file mode 100644 index 000000000..e9a27583a --- /dev/null +++ b/vendor/google.golang.org/protobuf/internal/impl/bitmap_race.go @@ -0,0 +1,126 @@ +// Copyright 2024 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +//go:build race + +package impl + +// When running under race detector, we add a presence map of bytes, that we can access +// in the hook functions so that we trigger the race detection whenever we have concurrent +// Read-Writes or Write-Writes. The race detector does not otherwise detect invalid concurrent +// access to lazy fields as all updates of bitmaps and pointers are done using atomic operations. +type RaceDetectHookData struct { + shadowPresence *[]byte +} + +// Hooks for presence bitmap operations that allocate, read and write the shadowPresence +// using non-atomic operations. +func (data *RaceDetectHookData) raceDetectHookAlloc(size presenceSize) { + sp := make([]byte, size) + atomicStoreShadowPresence(&data.shadowPresence, &sp) +} + +func (p presence) raceDetectHookPresent(num uint32) { + data := p.toRaceDetectData() + if data == nil { + return + } + sp := atomicLoadShadowPresence(&data.shadowPresence) + if sp != nil { + _ = (*sp)[num] + } +} + +func (p presence) raceDetectHookSetPresent(num uint32, size presenceSize) { + data := p.toRaceDetectData() + if data == nil { + return + } + sp := atomicLoadShadowPresence(&data.shadowPresence) + if sp == nil { + data.raceDetectHookAlloc(size) + sp = atomicLoadShadowPresence(&data.shadowPresence) + } + (*sp)[num] = 1 +} + +func (p presence) raceDetectHookClearPresent(num uint32) { + data := p.toRaceDetectData() + if data == nil { + return + } + sp := atomicLoadShadowPresence(&data.shadowPresence) + if sp != nil { + (*sp)[num] = 0 + + } +} + +// raceDetectHookAllocAndCopy allocates a new shadowPresence slice at lazy and copies +// shadowPresence bytes from src to lazy. +func (p presence) raceDetectHookAllocAndCopy(q presence) { + sData := q.toRaceDetectData() + dData := p.toRaceDetectData() + if sData == nil { + return + } + srcSp := atomicLoadShadowPresence(&sData.shadowPresence) + if srcSp == nil { + atomicStoreShadowPresence(&dData.shadowPresence, nil) + return + } + n := len(*srcSp) + dSlice := make([]byte, n) + atomicStoreShadowPresence(&dData.shadowPresence, &dSlice) + for i := 0; i < n; i++ { + dSlice[i] = (*srcSp)[i] + } +} + +// raceDetectHookPresent is called by the generated file interface +// (*proto.internalFuncs) Present to optionally read an unprotected +// shadow bitmap when race detection is enabled. In regular code it is +// a noop. +func raceDetectHookPresent(field *uint32, num uint32) { + data := findPointerToRaceDetectData(field, num) + if data == nil { + return + } + sp := atomicLoadShadowPresence(&data.shadowPresence) + if sp != nil { + _ = (*sp)[num] + } +} + +// raceDetectHookSetPresent is called by the generated file interface +// (*proto.internalFuncs) SetPresent to optionally write an unprotected +// shadow bitmap when race detection is enabled. In regular code it is +// a noop. +func raceDetectHookSetPresent(field *uint32, num uint32, size presenceSize) { + data := findPointerToRaceDetectData(field, num) + if data == nil { + return + } + sp := atomicLoadShadowPresence(&data.shadowPresence) + if sp == nil { + data.raceDetectHookAlloc(size) + sp = atomicLoadShadowPresence(&data.shadowPresence) + } + (*sp)[num] = 1 +} + +// raceDetectHookClearPresent is called by the generated file interface +// (*proto.internalFuncs) ClearPresent to optionally write an unprotected +// shadow bitmap when race detection is enabled. In regular code it is +// a noop. +func raceDetectHookClearPresent(field *uint32, num uint32) { + data := findPointerToRaceDetectData(field, num) + if data == nil { + return + } + sp := atomicLoadShadowPresence(&data.shadowPresence) + if sp != nil { + (*sp)[num] = 0 + } +} |