}

// Implemented in the runtime package (runtime/sys_openbsd3.go)
func syscall(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
func syscallX(fn, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno)
func syscall6(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
func syscall6X(fn, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno)
func syscall10(fn, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10 uintptr) (r1, r2 uintptr, err Errno)

//  v5.1: pidfd_send_signal syscall;
//  v5.2: CLONE_PIDFD flag for clone syscall;
//  v5.3: pidfd_open syscall, clone3 syscall;
//  v5.4: P_PIDFD idtype support for waitid syscall;
//  v5.6: pidfd_getfd syscall.

package os

import (
	"errors"
	"internal/syscall/unix"
	"sync"
	"syscall"
	"unsafe"
)

func ensurePidfd(sysAttr *syscall.SysProcAttr) *syscall.SysProcAttr {
	if !pidfdWorks() {

// Copyright 2023 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.

// Tests syscall P stealing from a goroutine and thread
// that have been in a syscall the entire generation.

package main

import (
	"internal/trace"
	"internal/trace/event/go122"
	testgen "internal/trace/internal/testgen/go122"
)

func main() {
	testgen.Main(gen)
}

// Copyright 2023 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.

// Tests syscall P stealing.
//
// Specifically, it tests a scenario where a thread 'steals'
// a P from itself. It's just a ProcStop with extra steps when
// it happens on the same P.

package main

import (
	"internal/trace"
	"internal/trace/event/go122"

	EvGoSysCall         = 28 // syscall enter [timestamp, stack]
	EvGoSysExit         = 29 // syscall exit [timestamp, goroutine id, seq, real timestamp]
	EvGoSysBlock        = 30 // syscall blocks [timestamp]
	EvGoWaiting         = 31 // denotes that goroutine is blocked when tracing starts [timestamp, goroutine id]
	EvGoInSyscall       = 32 // denotes that goroutine is in syscall when tracing starts [timestamp, goroutine id]

// Copyright 2023 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.

// Tests syscall P stealing.
//
// Specifically, it tests a scenerio wherein, without a
// P sequence number of GoSyscallBegin, the syscall that
// a ProcSteal applies to is ambiguous. This only happens in
// practice when the events aren't already properly ordered

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Tests a G being created from within a syscall.
//
// Specifically, it tests a scenerio wherein a C
// thread is calling into Go, creating a goroutine in
// a syscall (in the tracer's model). Because the actual
// m can be reused, it's possible for that m to have never
// had its P (in _Psyscall) stolen if the runtime doesn't

// license that can be found in the LICENSE file.

// Tests syscall P stealing at a generation boundary.

package main

import (
	"internal/trace"
	"internal/trace/event/go122"
	testgen "internal/trace/internal/testgen/go122"
)

func main() {
	testgen.Main(gen)
}

func gen(t *testgen.Trace) {
	g := t.Generation(1)

	// One goroutine is exiting with a syscall. It already
	// acquired a new P.

// license that can be found in the LICENSE file.

// Tests syscall P stealing.

package main

import (
	"internal/trace"
	"internal/trace/event/go122"
	testgen "internal/trace/internal/testgen/go122"
)

func main() {
	testgen.Main(gen)
}

func gen(t *testgen.Trace) {
	g := t.Generation(1)

	// One goroutine enters a syscall, grabs a P, and starts running.
	b0 := g.Batch(trace.ThreadID(0), 0)

// license that can be found in the LICENSE file.

// Tests syscall P stealing.

package main

import (
	"internal/trace"
	"internal/trace/event/go122"
	testgen "internal/trace/internal/testgen/go122"
)

func main() {
	testgen.Main(gen)
}

func gen(t *testgen.Trace) {
	g := t.Generation(1)

	// One goroutine enters a syscall.
	b0 := g.Batch(trace.ThreadID(0), 0)