mirror of
https://github.com/superseriousbusiness/gotosocial.git
synced 2024-12-03 22:06:31 +00:00
124 lines
3 KiB
Go
124 lines
3 KiB
Go
/*
|
|
* Copyright 2021 ByteDance Inc.
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
package rt
|
|
|
|
import (
|
|
`os`
|
|
`sync/atomic`
|
|
`unsafe`
|
|
|
|
`golang.org/x/arch/x86/x86asm`
|
|
)
|
|
|
|
const (
|
|
_MaxInstr = 15
|
|
)
|
|
|
|
func isvar(arg x86asm.Arg) bool {
|
|
v, ok := arg.(x86asm.Mem)
|
|
return ok && v.Base == x86asm.RIP
|
|
}
|
|
|
|
func iszero(arg x86asm.Arg) bool {
|
|
v, ok := arg.(x86asm.Imm)
|
|
return ok && v == 0
|
|
}
|
|
|
|
func GcwbAddr() uintptr {
|
|
var err error
|
|
var off uintptr
|
|
var ins x86asm.Inst
|
|
|
|
/* get the function address */
|
|
pc := uintptr(0)
|
|
fp := FuncAddr(atomic.StorePointer)
|
|
|
|
/* search within the first 16 instructions */
|
|
for i := 0; i < 16; i++ {
|
|
mem := unsafe.Pointer(uintptr(fp) + pc)
|
|
buf := BytesFrom(mem, _MaxInstr, _MaxInstr)
|
|
|
|
/* disassemble the instruction */
|
|
if ins, err = x86asm.Decode(buf, 64); err != nil {
|
|
panic("gcwbaddr: " + err.Error())
|
|
}
|
|
|
|
/* check for a byte comparison with zero */
|
|
if ins.Op == x86asm.CMP && ins.MemBytes == 1 && isvar(ins.Args[0]) && iszero(ins.Args[1]) {
|
|
off = pc + uintptr(ins.Len) + uintptr(ins.Args[0].(x86asm.Mem).Disp)
|
|
break
|
|
}
|
|
|
|
/* move to next instruction */
|
|
nb := ins.Len
|
|
pc += uintptr(nb)
|
|
}
|
|
|
|
/* check for address */
|
|
if off == 0 {
|
|
panic("gcwbaddr: could not locate the variable `writeBarrier`")
|
|
} else {
|
|
return uintptr(fp) + off
|
|
}
|
|
}
|
|
|
|
// StopProfiling is used to stop traceback introduced by SIGPROF while native code is running.
|
|
// WARN: this option is only a workaround for traceback issue (https://github.com/bytedance/sonic/issues/310),
|
|
// and will be dropped when the issue is fixed.
|
|
var StopProfiling = os.Getenv("SONIC_STOP_PROFILING") != ""
|
|
|
|
// WARN: must be aligned with runtime.Prof
|
|
// type Prof struct {
|
|
// signalLock uint32
|
|
// hz int32
|
|
// }
|
|
|
|
var (
|
|
// // go:linkname runtimeProf runtime.prof
|
|
// runtimeProf Prof
|
|
|
|
// count of native-C calls
|
|
yieldCount uint32
|
|
|
|
// previous value of runtimeProf.hz
|
|
oldHz int32
|
|
)
|
|
|
|
//go:nosplit
|
|
func MoreStack(size uintptr)
|
|
|
|
func StopProf()
|
|
|
|
// func StopProf() {
|
|
// atomic.AddUint32(&yieldCount, 1)
|
|
// if runtimeProf.hz != 0 {
|
|
// oldHz = runtimeProf.hz
|
|
// runtimeProf.hz = 0
|
|
// }
|
|
// }
|
|
|
|
func StartProf()
|
|
|
|
// func StartProf() {
|
|
// atomic.AddUint32(&yieldCount, ^uint32(0))
|
|
// if yieldCount == 0 && runtimeProf.hz == 0 {
|
|
// if oldHz == 0 {
|
|
// oldHz = 100
|
|
// }
|
|
// runtimeProf.hz = oldHz
|
|
// }
|
|
// }
|