os: consolidate os{1,2}_*.go files

Change-Id: I463ca59f486b2842f67f151a55f530ee10663830
Reviewed-on: https://go-review.googlesource.com/21568
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/runtime/os1_dragonfly.go b/src/runtime/os1_dragonfly.go
deleted file mode 100644
index d7044ae..0000000
--- a/src/runtime/os1_dragonfly.go
+++ /dev/null
@@ -1,270 +0,0 @@
-// Copyright 2011 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.
-
-package runtime
-
-import "unsafe"
-
-// From DragonFly's <sys/sysctl.h>
-const (
-	_CTL_HW  = 6
-	_HW_NCPU = 3
-)
-
-var sigset_all = sigset{[4]uint32{^uint32(0), ^uint32(0), ^uint32(0), ^uint32(0)}}
-
-func getncpu() int32 {
-	mib := [2]uint32{_CTL_HW, _HW_NCPU}
-	out := uint32(0)
-	nout := unsafe.Sizeof(out)
-	ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
-	if ret >= 0 {
-		return int32(out)
-	}
-	return 1
-}
-
-//go:nosplit
-func futexsleep(addr *uint32, val uint32, ns int64) {
-	systemstack(func() {
-		futexsleep1(addr, val, ns)
-	})
-}
-
-func futexsleep1(addr *uint32, val uint32, ns int64) {
-	var timeout int32
-	if ns >= 0 {
-		// The timeout is specified in microseconds - ensure that we
-		// do not end up dividing to zero, which would put us to sleep
-		// indefinitely...
-		timeout = timediv(ns, 1000, nil)
-		if timeout == 0 {
-			timeout = 1
-		}
-	}
-
-	// sys_umtx_sleep will return EWOULDBLOCK (EAGAIN) when the timeout
-	// expires or EBUSY if the mutex value does not match.
-	ret := sys_umtx_sleep(addr, int32(val), timeout)
-	if ret >= 0 || ret == -_EINTR || ret == -_EAGAIN || ret == -_EBUSY {
-		return
-	}
-
-	print("umtx_sleep addr=", addr, " val=", val, " ret=", ret, "\n")
-	*(*int32)(unsafe.Pointer(uintptr(0x1005))) = 0x1005
-}
-
-//go:nosplit
-func futexwakeup(addr *uint32, cnt uint32) {
-	ret := sys_umtx_wakeup(addr, int32(cnt))
-	if ret >= 0 {
-		return
-	}
-
-	systemstack(func() {
-		print("umtx_wake_addr=", addr, " ret=", ret, "\n")
-		*(*int32)(unsafe.Pointer(uintptr(0x1006))) = 0x1006
-	})
-}
-
-func lwp_start(uintptr)
-
-// May run with m.p==nil, so write barriers are not allowed.
-//go:nowritebarrier
-func newosproc(mp *m, stk unsafe.Pointer) {
-	if false {
-		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " lwp_start=", funcPC(lwp_start), " id=", mp.id, " ostk=", &mp, "\n")
-	}
-
-	var oset sigset
-	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
-
-	params := lwpparams{
-		start_func: funcPC(lwp_start),
-		arg:        unsafe.Pointer(mp),
-		stack:      uintptr(stk),
-		tid1:       unsafe.Pointer(&mp.procid),
-		tid2:       nil,
-	}
-
-	lwp_create(&params)
-	sigprocmask(_SIG_SETMASK, &oset, nil)
-}
-
-func osinit() {
-	ncpu = getncpu()
-}
-
-var urandom_dev = []byte("/dev/urandom\x00")
-
-//go:nosplit
-func getRandomData(r []byte) {
-	fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0)
-	n := read(fd, unsafe.Pointer(&r[0]), int32(len(r)))
-	closefd(fd)
-	extendRandom(r, int(n))
-}
-
-func goenvs() {
-	goenvs_unix()
-}
-
-// Called to initialize a new m (including the bootstrap m).
-// Called on the parent thread (main thread in case of bootstrap), can allocate memory.
-func mpreinit(mp *m) {
-	mp.gsignal = malg(32 * 1024)
-	mp.gsignal.m = mp
-}
-
-//go:nosplit
-func msigsave(mp *m) {
-	sigprocmask(_SIG_SETMASK, nil, &mp.sigmask)
-}
-
-//go:nosplit
-func msigrestore(sigmask sigset) {
-	sigprocmask(_SIG_SETMASK, &sigmask, nil)
-}
-
-//go:nosplit
-func sigblock() {
-	sigprocmask(_SIG_SETMASK, &sigset_all, nil)
-}
-
-// Called to initialize a new m (including the bootstrap m).
-// Called on the new thread, cannot allocate memory.
-func minit() {
-	_g_ := getg()
-
-	// m.procid is a uint64, but lwp_start writes an int32. Fix it up.
-	_g_.m.procid = uint64(*(*int32)(unsafe.Pointer(&_g_.m.procid)))
-
-	// Initialize signal handling.
-
-	// On DragonFly a thread created by pthread_create inherits
-	// the signal stack of the creating thread. We always create
-	// a new signal stack here, to avoid having two Go threads
-	// using the same signal stack. This breaks the case of a
-	// thread created in C that calls sigaltstack and then calls a
-	// Go function, because we will lose track of the C code's
-	// sigaltstack, but it's the best we can do.
-	signalstack(&_g_.m.gsignal.stack)
-	_g_.m.newSigstack = true
-
-	// restore signal mask from m.sigmask and unblock essential signals
-	nmask := _g_.m.sigmask
-	for i := range sigtable {
-		if sigtable[i].flags&_SigUnblock != 0 {
-			nmask.__bits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
-		}
-	}
-	sigprocmask(_SIG_SETMASK, &nmask, nil)
-}
-
-// Called from dropm to undo the effect of an minit.
-//go:nosplit
-func unminit() {
-	if getg().m.newSigstack {
-		signalstack(nil)
-	}
-}
-
-func memlimit() uintptr {
-	/*
-		                TODO: Convert to Go when something actually uses the result.
-
-				Rlimit rl;
-				extern byte runtime·text[], runtime·end[];
-				uintptr used;
-
-				if(runtime·getrlimit(RLIMIT_AS, &rl) != 0)
-					return 0;
-				if(rl.rlim_cur >= 0x7fffffff)
-					return 0;
-
-				// Estimate our VM footprint excluding the heap.
-				// Not an exact science: use size of binary plus
-				// some room for thread stacks.
-				used = runtime·end - runtime·text + (64<<20);
-				if(used >= rl.rlim_cur)
-					return 0;
-
-				// If there's not at least 16 MB left, we're probably
-				// not going to be able to do much. Treat as no limit.
-				rl.rlim_cur -= used;
-				if(rl.rlim_cur < (16<<20))
-					return 0;
-
-				return rl.rlim_cur - used;
-	*/
-	return 0
-}
-
-func sigtramp()
-
-type sigactiont struct {
-	sa_sigaction uintptr
-	sa_flags     int32
-	sa_mask      sigset
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func setsig(i int32, fn uintptr, restart bool) {
-	var sa sigactiont
-	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK
-	if restart {
-		sa.sa_flags |= _SA_RESTART
-	}
-	sa.sa_mask = sigset_all
-	if fn == funcPC(sighandler) {
-		fn = funcPC(sigtramp)
-	}
-	sa.sa_sigaction = fn
-	sigaction(i, &sa, nil)
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func setsigstack(i int32) {
-	throw("setsigstack")
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func getsig(i int32) uintptr {
-	var sa sigactiont
-	sigaction(i, nil, &sa)
-	if sa.sa_sigaction == funcPC(sigtramp) {
-		return funcPC(sighandler)
-	}
-	return sa.sa_sigaction
-}
-
-//go:nosplit
-func signalstack(s *stack) {
-	var st sigaltstackt
-	if s == nil {
-		st.ss_flags = _SS_DISABLE
-	} else {
-		st.ss_sp = s.lo
-		st.ss_size = s.hi - s.lo
-		st.ss_flags = 0
-	}
-	sigaltstack(&st, nil)
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func updatesigmask(m sigmask) {
-	var mask sigset
-	copy(mask.__bits[:], m[:])
-	sigprocmask(_SIG_SETMASK, &mask, nil)
-}
-
-func unblocksig(sig int32) {
-	var mask sigset
-	mask.__bits[(sig-1)/32] |= 1 << ((uint32(sig) - 1) & 31)
-	sigprocmask(_SIG_UNBLOCK, &mask, nil)
-}
diff --git a/src/runtime/os1_linux_generic.go b/src/runtime/os1_linux_generic.go
deleted file mode 100644
index 50d6d6a..0000000
--- a/src/runtime/os1_linux_generic.go
+++ /dev/null
@@ -1,28 +0,0 @@
-// Copyright 2009 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.
-
-// +build !mips64
-// +build !mips64le
-// +build !s390x
-// +build linux
-
-package runtime
-
-var sigset_all = sigset{^uint32(0), ^uint32(0)}
-
-func sigaddset(mask *sigset, i int) {
-	(*mask)[(i-1)/32] |= 1 << ((uint32(i) - 1) & 31)
-}
-
-func sigdelset(mask *sigset, i int) {
-	(*mask)[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
-}
-
-func sigfillset(mask *uint64) {
-	*mask = ^uint64(0)
-}
-
-func sigcopyset(mask *sigset, m sigmask) {
-	copy((*mask)[:], m[:])
-}
diff --git a/src/runtime/os1_linux_mips64x.go b/src/runtime/os1_linux_mips64x.go
deleted file mode 100644
index 701e979..0000000
--- a/src/runtime/os1_linux_mips64x.go
+++ /dev/null
@@ -1,26 +0,0 @@
-// Copyright 2015 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.
-
-// +build mips64 mips64le
-// +build linux
-
-package runtime
-
-var sigset_all = sigset{^uint64(0), ^uint64(0)}
-
-func sigaddset(mask *sigset, i int) {
-	(*mask)[(i-1)/64] |= 1 << ((uint32(i) - 1) & 63)
-}
-
-func sigdelset(mask *sigset, i int) {
-	(*mask)[(i-1)/64] &^= 1 << ((uint32(i) - 1) & 63)
-}
-
-func sigfillset(mask *[2]uint64) {
-	(*mask)[0], (*mask)[1] = ^uint64(0), ^uint64(0)
-}
-
-func sigcopyset(mask *sigset, m sigmask) {
-	(*mask)[0] = uint64(m[0]) | uint64(m[1])<<32
-}
diff --git a/src/runtime/os1_netbsd.go b/src/runtime/os1_netbsd.go
deleted file mode 100644
index 3c3b641..0000000
--- a/src/runtime/os1_netbsd.go
+++ /dev/null
@@ -1,275 +0,0 @@
-// Copyright 2011 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.
-
-package runtime
-
-import (
-	"runtime/internal/atomic"
-	"unsafe"
-)
-
-const (
-	_ESRCH     = 3
-	_ETIMEDOUT = 60
-
-	// From NetBSD's <sys/time.h>
-	_CLOCK_REALTIME  = 0
-	_CLOCK_VIRTUAL   = 1
-	_CLOCK_PROF      = 2
-	_CLOCK_MONOTONIC = 3
-)
-
-var sigset_all = sigset{[4]uint32{^uint32(0), ^uint32(0), ^uint32(0), ^uint32(0)}}
-
-// From NetBSD's <sys/sysctl.h>
-const (
-	_CTL_HW  = 6
-	_HW_NCPU = 3
-)
-
-func getncpu() int32 {
-	mib := [2]uint32{_CTL_HW, _HW_NCPU}
-	out := uint32(0)
-	nout := unsafe.Sizeof(out)
-	ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
-	if ret >= 0 {
-		return int32(out)
-	}
-	return 1
-}
-
-//go:nosplit
-func semacreate(mp *m) {
-}
-
-//go:nosplit
-func semasleep(ns int64) int32 {
-	_g_ := getg()
-
-	// Compute sleep deadline.
-	var tsp *timespec
-	if ns >= 0 {
-		var ts timespec
-		var nsec int32
-		ns += nanotime()
-		ts.set_sec(timediv(ns, 1000000000, &nsec))
-		ts.set_nsec(nsec)
-		tsp = &ts
-	}
-
-	for {
-		v := atomic.Load(&_g_.m.waitsemacount)
-		if v > 0 {
-			if atomic.Cas(&_g_.m.waitsemacount, v, v-1) {
-				return 0 // semaphore acquired
-			}
-			continue
-		}
-
-		// Sleep until unparked by semawakeup or timeout.
-		ret := lwp_park(tsp, 0, unsafe.Pointer(&_g_.m.waitsemacount), nil)
-		if ret == _ETIMEDOUT {
-			return -1
-		}
-	}
-}
-
-//go:nosplit
-func semawakeup(mp *m) {
-	atomic.Xadd(&mp.waitsemacount, 1)
-	// From NetBSD's _lwp_unpark(2) manual:
-	// "If the target LWP is not currently waiting, it will return
-	// immediately upon the next call to _lwp_park()."
-	ret := lwp_unpark(int32(mp.procid), unsafe.Pointer(&mp.waitsemacount))
-	if ret != 0 && ret != _ESRCH {
-		// semawakeup can be called on signal stack.
-		systemstack(func() {
-			print("thrwakeup addr=", &mp.waitsemacount, " sem=", mp.waitsemacount, " ret=", ret, "\n")
-		})
-	}
-}
-
-// May run with m.p==nil, so write barriers are not allowed.
-//go:nowritebarrier
-func newosproc(mp *m, stk unsafe.Pointer) {
-	if false {
-		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " id=", mp.id, " ostk=", &mp, "\n")
-	}
-
-	var uc ucontextt
-	getcontext(unsafe.Pointer(&uc))
-
-	uc.uc_flags = _UC_SIGMASK | _UC_CPU
-	uc.uc_link = nil
-	uc.uc_sigmask = sigset_all
-
-	lwp_mcontext_init(&uc.uc_mcontext, stk, mp, mp.g0, funcPC(netbsdMstart))
-
-	ret := lwp_create(unsafe.Pointer(&uc), 0, unsafe.Pointer(&mp.procid))
-	if ret < 0 {
-		print("runtime: failed to create new OS thread (have ", mcount()-1, " already; errno=", -ret, ")\n")
-		throw("runtime.newosproc")
-	}
-}
-
-// netbsdMStart is the function call that starts executing a newly
-// created thread. On NetBSD, a new thread inherits the signal stack
-// of the creating thread. That confuses minit, so we remove that
-// signal stack here before calling the regular mstart. It's a bit
-// baroque to remove a signal stack here only to add one in minit, but
-// it's a simple change that keeps NetBSD working like other OS's.
-// At this point all signals are blocked, so there is no race.
-//go:nosplit
-func netbsdMstart() {
-	signalstack(nil)
-	mstart()
-}
-
-func osinit() {
-	ncpu = getncpu()
-}
-
-var urandom_dev = []byte("/dev/urandom\x00")
-
-//go:nosplit
-func getRandomData(r []byte) {
-	fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0)
-	n := read(fd, unsafe.Pointer(&r[0]), int32(len(r)))
-	closefd(fd)
-	extendRandom(r, int(n))
-}
-
-func goenvs() {
-	goenvs_unix()
-}
-
-// Called to initialize a new m (including the bootstrap m).
-// Called on the parent thread (main thread in case of bootstrap), can allocate memory.
-func mpreinit(mp *m) {
-	mp.gsignal = malg(32 * 1024)
-	mp.gsignal.m = mp
-}
-
-//go:nosplit
-func msigsave(mp *m) {
-	sigprocmask(_SIG_SETMASK, nil, &mp.sigmask)
-}
-
-//go:nosplit
-func msigrestore(sigmask sigset) {
-	sigprocmask(_SIG_SETMASK, &sigmask, nil)
-}
-
-//go:nosplit
-func sigblock() {
-	sigprocmask(_SIG_SETMASK, &sigset_all, nil)
-}
-
-// Called to initialize a new m (including the bootstrap m).
-// Called on the new thread, cannot allocate memory.
-func minit() {
-	_g_ := getg()
-	_g_.m.procid = uint64(lwp_self())
-
-	// Initialize signal handling.
-
-	// On NetBSD a thread created by pthread_create inherits the
-	// signal stack of the creating thread. We always create a
-	// new signal stack here, to avoid having two Go threads using
-	// the same signal stack. This breaks the case of a thread
-	// created in C that calls sigaltstack and then calls a Go
-	// function, because we will lose track of the C code's
-	// sigaltstack, but it's the best we can do.
-	signalstack(&_g_.m.gsignal.stack)
-	_g_.m.newSigstack = true
-
-	// restore signal mask from m.sigmask and unblock essential signals
-	nmask := _g_.m.sigmask
-	for i := range sigtable {
-		if sigtable[i].flags&_SigUnblock != 0 {
-			nmask.__bits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
-		}
-	}
-	sigprocmask(_SIG_SETMASK, &nmask, nil)
-}
-
-// Called from dropm to undo the effect of an minit.
-//go:nosplit
-func unminit() {
-	if getg().m.newSigstack {
-		signalstack(nil)
-	}
-}
-
-func memlimit() uintptr {
-	return 0
-}
-
-func sigtramp()
-
-type sigactiont struct {
-	sa_sigaction uintptr
-	sa_mask      sigset
-	sa_flags     int32
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func setsig(i int32, fn uintptr, restart bool) {
-	var sa sigactiont
-	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK
-	if restart {
-		sa.sa_flags |= _SA_RESTART
-	}
-	sa.sa_mask = sigset_all
-	if fn == funcPC(sighandler) {
-		fn = funcPC(sigtramp)
-	}
-	sa.sa_sigaction = fn
-	sigaction(i, &sa, nil)
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func setsigstack(i int32) {
-	throw("setsigstack")
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func getsig(i int32) uintptr {
-	var sa sigactiont
-	sigaction(i, nil, &sa)
-	if sa.sa_sigaction == funcPC(sigtramp) {
-		return funcPC(sighandler)
-	}
-	return sa.sa_sigaction
-}
-
-//go:nosplit
-func signalstack(s *stack) {
-	var st sigaltstackt
-	if s == nil {
-		st.ss_flags = _SS_DISABLE
-	} else {
-		st.ss_sp = s.lo
-		st.ss_size = s.hi - s.lo
-		st.ss_flags = 0
-	}
-	sigaltstack(&st, nil)
-}
-
-//go:nosplit
-//go:nowritebarrierrec
-func updatesigmask(m sigmask) {
-	var mask sigset
-	copy(mask.__bits[:], m[:])
-	sigprocmask(_SIG_SETMASK, &mask, nil)
-}
-
-func unblocksig(sig int32) {
-	var mask sigset
-	mask.__bits[(sig-1)/32] |= 1 << ((uint32(sig) - 1) & 31)
-	sigprocmask(_SIG_UNBLOCK, &mask, nil)
-}
diff --git a/src/runtime/os2_dragonfly.go b/src/runtime/os2_dragonfly.go
deleted file mode 100644
index 6ea2da0..0000000
--- a/src/runtime/os2_dragonfly.go
+++ /dev/null
@@ -1,15 +0,0 @@
-// Copyright 2011 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.
-
-package runtime
-
-const (
-	_NSIG        = 33
-	_SI_USER     = 0
-	_SS_DISABLE  = 4
-	_RLIMIT_AS   = 10
-	_SIG_BLOCK   = 1
-	_SIG_UNBLOCK = 2
-	_SIG_SETMASK = 3
-)
diff --git a/src/runtime/os2_linux_mips64x.go b/src/runtime/os2_linux_mips64x.go
deleted file mode 100644
index 9a6a92a..0000000
--- a/src/runtime/os2_linux_mips64x.go
+++ /dev/null
@@ -1,25 +0,0 @@
-// Copyright 2015 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.
-
-// +build linux
-// +build mips64 mips64le
-
-package runtime
-
-const (
-	_SS_DISABLE  = 2
-	_NSIG        = 65
-	_SI_USER     = 0
-	_SIG_BLOCK   = 1
-	_SIG_UNBLOCK = 2
-	_SIG_SETMASK = 3
-	_RLIMIT_AS   = 6
-)
-
-type sigset [2]uint64
-
-type rlimit struct {
-	rlim_cur uintptr
-	rlim_max uintptr
-}
diff --git a/src/runtime/os2_netbsd.go b/src/runtime/os2_netbsd.go
deleted file mode 100644
index 405dd5e..0000000
--- a/src/runtime/os2_netbsd.go
+++ /dev/null
@@ -1,18 +0,0 @@
-// Copyright 2010 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.
-
-package runtime
-
-const (
-	_SS_DISABLE  = 4
-	_SIG_BLOCK   = 1
-	_SIG_UNBLOCK = 2
-	_SIG_SETMASK = 3
-	_NSIG        = 33
-	_SI_USER     = 0
-
-	// From NetBSD's <sys/ucontext.h>
-	_UC_SIGMASK = 0x01
-	_UC_CPU     = 0x04
-)
diff --git a/src/runtime/os_dragonfly.go b/src/runtime/os_dragonfly.go
index c3833a3..78a150e 100644
--- a/src/runtime/os_dragonfly.go
+++ b/src/runtime/os_dragonfly.go
@@ -6,6 +6,16 @@
 
 import "unsafe"
 
+const (
+	_NSIG        = 33
+	_SI_USER     = 0
+	_SS_DISABLE  = 4
+	_RLIMIT_AS   = 10
+	_SIG_BLOCK   = 1
+	_SIG_UNBLOCK = 2
+	_SIG_SETMASK = 3
+)
+
 type mOS struct{}
 
 //go:noescape
@@ -41,3 +51,266 @@
 func osyield()
 
 const stackSystem = 0
+
+// From DragonFly's <sys/sysctl.h>
+const (
+	_CTL_HW  = 6
+	_HW_NCPU = 3
+)
+
+var sigset_all = sigset{[4]uint32{^uint32(0), ^uint32(0), ^uint32(0), ^uint32(0)}}
+
+func getncpu() int32 {
+	mib := [2]uint32{_CTL_HW, _HW_NCPU}
+	out := uint32(0)
+	nout := unsafe.Sizeof(out)
+	ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
+	if ret >= 0 {
+		return int32(out)
+	}
+	return 1
+}
+
+//go:nosplit
+func futexsleep(addr *uint32, val uint32, ns int64) {
+	systemstack(func() {
+		futexsleep1(addr, val, ns)
+	})
+}
+
+func futexsleep1(addr *uint32, val uint32, ns int64) {
+	var timeout int32
+	if ns >= 0 {
+		// The timeout is specified in microseconds - ensure that we
+		// do not end up dividing to zero, which would put us to sleep
+		// indefinitely...
+		timeout = timediv(ns, 1000, nil)
+		if timeout == 0 {
+			timeout = 1
+		}
+	}
+
+	// sys_umtx_sleep will return EWOULDBLOCK (EAGAIN) when the timeout
+	// expires or EBUSY if the mutex value does not match.
+	ret := sys_umtx_sleep(addr, int32(val), timeout)
+	if ret >= 0 || ret == -_EINTR || ret == -_EAGAIN || ret == -_EBUSY {
+		return
+	}
+
+	print("umtx_sleep addr=", addr, " val=", val, " ret=", ret, "\n")
+	*(*int32)(unsafe.Pointer(uintptr(0x1005))) = 0x1005
+}
+
+//go:nosplit
+func futexwakeup(addr *uint32, cnt uint32) {
+	ret := sys_umtx_wakeup(addr, int32(cnt))
+	if ret >= 0 {
+		return
+	}
+
+	systemstack(func() {
+		print("umtx_wake_addr=", addr, " ret=", ret, "\n")
+		*(*int32)(unsafe.Pointer(uintptr(0x1006))) = 0x1006
+	})
+}
+
+func lwp_start(uintptr)
+
+// May run with m.p==nil, so write barriers are not allowed.
+//go:nowritebarrier
+func newosproc(mp *m, stk unsafe.Pointer) {
+	if false {
+		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " lwp_start=", funcPC(lwp_start), " id=", mp.id, " ostk=", &mp, "\n")
+	}
+
+	var oset sigset
+	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
+
+	params := lwpparams{
+		start_func: funcPC(lwp_start),
+		arg:        unsafe.Pointer(mp),
+		stack:      uintptr(stk),
+		tid1:       unsafe.Pointer(&mp.procid),
+		tid2:       nil,
+	}
+
+	lwp_create(&params)
+	sigprocmask(_SIG_SETMASK, &oset, nil)
+}
+
+func osinit() {
+	ncpu = getncpu()
+}
+
+var urandom_dev = []byte("/dev/urandom\x00")
+
+//go:nosplit
+func getRandomData(r []byte) {
+	fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0)
+	n := read(fd, unsafe.Pointer(&r[0]), int32(len(r)))
+	closefd(fd)
+	extendRandom(r, int(n))
+}
+
+func goenvs() {
+	goenvs_unix()
+}
+
+// Called to initialize a new m (including the bootstrap m).
+// Called on the parent thread (main thread in case of bootstrap), can allocate memory.
+func mpreinit(mp *m) {
+	mp.gsignal = malg(32 * 1024)
+	mp.gsignal.m = mp
+}
+
+//go:nosplit
+func msigsave(mp *m) {
+	sigprocmask(_SIG_SETMASK, nil, &mp.sigmask)
+}
+
+//go:nosplit
+func msigrestore(sigmask sigset) {
+	sigprocmask(_SIG_SETMASK, &sigmask, nil)
+}
+
+//go:nosplit
+func sigblock() {
+	sigprocmask(_SIG_SETMASK, &sigset_all, nil)
+}
+
+// Called to initialize a new m (including the bootstrap m).
+// Called on the new thread, cannot allocate memory.
+func minit() {
+	_g_ := getg()
+
+	// m.procid is a uint64, but lwp_start writes an int32. Fix it up.
+	_g_.m.procid = uint64(*(*int32)(unsafe.Pointer(&_g_.m.procid)))
+
+	// Initialize signal handling.
+
+	// On DragonFly a thread created by pthread_create inherits
+	// the signal stack of the creating thread. We always create
+	// a new signal stack here, to avoid having two Go threads
+	// using the same signal stack. This breaks the case of a
+	// thread created in C that calls sigaltstack and then calls a
+	// Go function, because we will lose track of the C code's
+	// sigaltstack, but it's the best we can do.
+	signalstack(&_g_.m.gsignal.stack)
+	_g_.m.newSigstack = true
+
+	// restore signal mask from m.sigmask and unblock essential signals
+	nmask := _g_.m.sigmask
+	for i := range sigtable {
+		if sigtable[i].flags&_SigUnblock != 0 {
+			nmask.__bits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
+		}
+	}
+	sigprocmask(_SIG_SETMASK, &nmask, nil)
+}
+
+// Called from dropm to undo the effect of an minit.
+//go:nosplit
+func unminit() {
+	if getg().m.newSigstack {
+		signalstack(nil)
+	}
+}
+
+func memlimit() uintptr {
+	/*
+		                TODO: Convert to Go when something actually uses the result.
+
+				Rlimit rl;
+				extern byte runtime·text[], runtime·end[];
+				uintptr used;
+
+				if(runtime·getrlimit(RLIMIT_AS, &rl) != 0)
+					return 0;
+				if(rl.rlim_cur >= 0x7fffffff)
+					return 0;
+
+				// Estimate our VM footprint excluding the heap.
+				// Not an exact science: use size of binary plus
+				// some room for thread stacks.
+				used = runtime·end - runtime·text + (64<<20);
+				if(used >= rl.rlim_cur)
+					return 0;
+
+				// If there's not at least 16 MB left, we're probably
+				// not going to be able to do much. Treat as no limit.
+				rl.rlim_cur -= used;
+				if(rl.rlim_cur < (16<<20))
+					return 0;
+
+				return rl.rlim_cur - used;
+	*/
+	return 0
+}
+
+func sigtramp()
+
+type sigactiont struct {
+	sa_sigaction uintptr
+	sa_flags     int32
+	sa_mask      sigset
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func setsig(i int32, fn uintptr, restart bool) {
+	var sa sigactiont
+	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK
+	if restart {
+		sa.sa_flags |= _SA_RESTART
+	}
+	sa.sa_mask = sigset_all
+	if fn == funcPC(sighandler) {
+		fn = funcPC(sigtramp)
+	}
+	sa.sa_sigaction = fn
+	sigaction(i, &sa, nil)
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func setsigstack(i int32) {
+	throw("setsigstack")
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func getsig(i int32) uintptr {
+	var sa sigactiont
+	sigaction(i, nil, &sa)
+	if sa.sa_sigaction == funcPC(sigtramp) {
+		return funcPC(sighandler)
+	}
+	return sa.sa_sigaction
+}
+
+//go:nosplit
+func signalstack(s *stack) {
+	var st sigaltstackt
+	if s == nil {
+		st.ss_flags = _SS_DISABLE
+	} else {
+		st.ss_sp = s.lo
+		st.ss_size = s.hi - s.lo
+		st.ss_flags = 0
+	}
+	sigaltstack(&st, nil)
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func updatesigmask(m sigmask) {
+	var mask sigset
+	copy(mask.__bits[:], m[:])
+	sigprocmask(_SIG_SETMASK, &mask, nil)
+}
+
+func unblocksig(sig int32) {
+	var mask sigset
+	mask.__bits[(sig-1)/32] |= 1 << ((uint32(sig) - 1) & 31)
+	sigprocmask(_SIG_UNBLOCK, &mask, nil)
+}
diff --git a/src/runtime/os2_linux_generic.go b/src/runtime/os_linux_generic.go
similarity index 63%
rename from src/runtime/os2_linux_generic.go
rename to src/runtime/os_linux_generic.go
index f1a2dd5..a16d140 100644
--- a/src/runtime/os2_linux_generic.go
+++ b/src/runtime/os_linux_generic.go
@@ -28,3 +28,21 @@
 	rlim_cur uintptr
 	rlim_max uintptr
 }
+
+var sigset_all = sigset{^uint32(0), ^uint32(0)}
+
+func sigaddset(mask *sigset, i int) {
+	(*mask)[(i-1)/32] |= 1 << ((uint32(i) - 1) & 31)
+}
+
+func sigdelset(mask *sigset, i int) {
+	(*mask)[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
+}
+
+func sigfillset(mask *uint64) {
+	*mask = ^uint64(0)
+}
+
+func sigcopyset(mask *sigset, m sigmask) {
+	copy((*mask)[:], m[:])
+}
diff --git a/src/runtime/os_linux_mips64x.go b/src/runtime/os_linux_mips64x.go
index 4d2e9e8..92b5c82 100644
--- a/src/runtime/os_linux_mips64x.go
+++ b/src/runtime/os_linux_mips64x.go
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build mips64 mips64le
 // +build linux
+// +build mips64 mips64le
 
 package runtime
 
@@ -16,3 +16,38 @@
 	// randomNumber provides better seeding of fastrand1.
 	return nanotime() + int64(randomNumber)
 }
+
+const (
+	_SS_DISABLE  = 2
+	_NSIG        = 65
+	_SI_USER     = 0
+	_SIG_BLOCK   = 1
+	_SIG_UNBLOCK = 2
+	_SIG_SETMASK = 3
+	_RLIMIT_AS   = 6
+)
+
+type sigset [2]uint64
+
+type rlimit struct {
+	rlim_cur uintptr
+	rlim_max uintptr
+}
+
+var sigset_all = sigset{^uint64(0), ^uint64(0)}
+
+func sigaddset(mask *sigset, i int) {
+	(*mask)[(i-1)/64] |= 1 << ((uint32(i) - 1) & 63)
+}
+
+func sigdelset(mask *sigset, i int) {
+	(*mask)[(i-1)/64] &^= 1 << ((uint32(i) - 1) & 63)
+}
+
+func sigfillset(mask *[2]uint64) {
+	(*mask)[0], (*mask)[1] = ^uint64(0), ^uint64(0)
+}
+
+func sigcopyset(mask *sigset, m sigmask) {
+	(*mask)[0] = uint64(m[0]) | uint64(m[1])<<32
+}
diff --git a/src/runtime/os_netbsd.go b/src/runtime/os_netbsd.go
index 0fba16d..41f34f7 100644
--- a/src/runtime/os_netbsd.go
+++ b/src/runtime/os_netbsd.go
@@ -4,7 +4,23 @@
 
 package runtime
 
-import "unsafe"
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+const (
+	_SS_DISABLE  = 4
+	_SIG_BLOCK   = 1
+	_SIG_UNBLOCK = 2
+	_SIG_SETMASK = 3
+	_NSIG        = 33
+	_SI_USER     = 0
+
+	// From NetBSD's <sys/ucontext.h>
+	_UC_SIGMASK = 0x01
+	_UC_CPU     = 0x04
+)
 
 type mOS struct {
 	waitsemacount uint32
@@ -45,3 +61,268 @@
 func lwp_self() int32
 
 func osyield()
+
+const (
+	_ESRCH     = 3
+	_ETIMEDOUT = 60
+
+	// From NetBSD's <sys/time.h>
+	_CLOCK_REALTIME  = 0
+	_CLOCK_VIRTUAL   = 1
+	_CLOCK_PROF      = 2
+	_CLOCK_MONOTONIC = 3
+)
+
+var sigset_all = sigset{[4]uint32{^uint32(0), ^uint32(0), ^uint32(0), ^uint32(0)}}
+
+// From NetBSD's <sys/sysctl.h>
+const (
+	_CTL_HW  = 6
+	_HW_NCPU = 3
+)
+
+func getncpu() int32 {
+	mib := [2]uint32{_CTL_HW, _HW_NCPU}
+	out := uint32(0)
+	nout := unsafe.Sizeof(out)
+	ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0)
+	if ret >= 0 {
+		return int32(out)
+	}
+	return 1
+}
+
+//go:nosplit
+func semacreate(mp *m) {
+}
+
+//go:nosplit
+func semasleep(ns int64) int32 {
+	_g_ := getg()
+
+	// Compute sleep deadline.
+	var tsp *timespec
+	if ns >= 0 {
+		var ts timespec
+		var nsec int32
+		ns += nanotime()
+		ts.set_sec(timediv(ns, 1000000000, &nsec))
+		ts.set_nsec(nsec)
+		tsp = &ts
+	}
+
+	for {
+		v := atomic.Load(&_g_.m.waitsemacount)
+		if v > 0 {
+			if atomic.Cas(&_g_.m.waitsemacount, v, v-1) {
+				return 0 // semaphore acquired
+			}
+			continue
+		}
+
+		// Sleep until unparked by semawakeup or timeout.
+		ret := lwp_park(tsp, 0, unsafe.Pointer(&_g_.m.waitsemacount), nil)
+		if ret == _ETIMEDOUT {
+			return -1
+		}
+	}
+}
+
+//go:nosplit
+func semawakeup(mp *m) {
+	atomic.Xadd(&mp.waitsemacount, 1)
+	// From NetBSD's _lwp_unpark(2) manual:
+	// "If the target LWP is not currently waiting, it will return
+	// immediately upon the next call to _lwp_park()."
+	ret := lwp_unpark(int32(mp.procid), unsafe.Pointer(&mp.waitsemacount))
+	if ret != 0 && ret != _ESRCH {
+		// semawakeup can be called on signal stack.
+		systemstack(func() {
+			print("thrwakeup addr=", &mp.waitsemacount, " sem=", mp.waitsemacount, " ret=", ret, "\n")
+		})
+	}
+}
+
+// May run with m.p==nil, so write barriers are not allowed.
+//go:nowritebarrier
+func newosproc(mp *m, stk unsafe.Pointer) {
+	if false {
+		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " id=", mp.id, " ostk=", &mp, "\n")
+	}
+
+	var uc ucontextt
+	getcontext(unsafe.Pointer(&uc))
+
+	uc.uc_flags = _UC_SIGMASK | _UC_CPU
+	uc.uc_link = nil
+	uc.uc_sigmask = sigset_all
+
+	lwp_mcontext_init(&uc.uc_mcontext, stk, mp, mp.g0, funcPC(netbsdMstart))
+
+	ret := lwp_create(unsafe.Pointer(&uc), 0, unsafe.Pointer(&mp.procid))
+	if ret < 0 {
+		print("runtime: failed to create new OS thread (have ", mcount()-1, " already; errno=", -ret, ")\n")
+		throw("runtime.newosproc")
+	}
+}
+
+// netbsdMStart is the function call that starts executing a newly
+// created thread. On NetBSD, a new thread inherits the signal stack
+// of the creating thread. That confuses minit, so we remove that
+// signal stack here before calling the regular mstart. It's a bit
+// baroque to remove a signal stack here only to add one in minit, but
+// it's a simple change that keeps NetBSD working like other OS's.
+// At this point all signals are blocked, so there is no race.
+//go:nosplit
+func netbsdMstart() {
+	signalstack(nil)
+	mstart()
+}
+
+func osinit() {
+	ncpu = getncpu()
+}
+
+var urandom_dev = []byte("/dev/urandom\x00")
+
+//go:nosplit
+func getRandomData(r []byte) {
+	fd := open(&urandom_dev[0], 0 /* O_RDONLY */, 0)
+	n := read(fd, unsafe.Pointer(&r[0]), int32(len(r)))
+	closefd(fd)
+	extendRandom(r, int(n))
+}
+
+func goenvs() {
+	goenvs_unix()
+}
+
+// Called to initialize a new m (including the bootstrap m).
+// Called on the parent thread (main thread in case of bootstrap), can allocate memory.
+func mpreinit(mp *m) {
+	mp.gsignal = malg(32 * 1024)
+	mp.gsignal.m = mp
+}
+
+//go:nosplit
+func msigsave(mp *m) {
+	sigprocmask(_SIG_SETMASK, nil, &mp.sigmask)
+}
+
+//go:nosplit
+func msigrestore(sigmask sigset) {
+	sigprocmask(_SIG_SETMASK, &sigmask, nil)
+}
+
+//go:nosplit
+func sigblock() {
+	sigprocmask(_SIG_SETMASK, &sigset_all, nil)
+}
+
+// Called to initialize a new m (including the bootstrap m).
+// Called on the new thread, cannot allocate memory.
+func minit() {
+	_g_ := getg()
+	_g_.m.procid = uint64(lwp_self())
+
+	// Initialize signal handling.
+
+	// On NetBSD a thread created by pthread_create inherits the
+	// signal stack of the creating thread. We always create a
+	// new signal stack here, to avoid having two Go threads using
+	// the same signal stack. This breaks the case of a thread
+	// created in C that calls sigaltstack and then calls a Go
+	// function, because we will lose track of the C code's
+	// sigaltstack, but it's the best we can do.
+	signalstack(&_g_.m.gsignal.stack)
+	_g_.m.newSigstack = true
+
+	// restore signal mask from m.sigmask and unblock essential signals
+	nmask := _g_.m.sigmask
+	for i := range sigtable {
+		if sigtable[i].flags&_SigUnblock != 0 {
+			nmask.__bits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
+		}
+	}
+	sigprocmask(_SIG_SETMASK, &nmask, nil)
+}
+
+// Called from dropm to undo the effect of an minit.
+//go:nosplit
+func unminit() {
+	if getg().m.newSigstack {
+		signalstack(nil)
+	}
+}
+
+func memlimit() uintptr {
+	return 0
+}
+
+func sigtramp()
+
+type sigactiont struct {
+	sa_sigaction uintptr
+	sa_mask      sigset
+	sa_flags     int32
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func setsig(i int32, fn uintptr, restart bool) {
+	var sa sigactiont
+	sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK
+	if restart {
+		sa.sa_flags |= _SA_RESTART
+	}
+	sa.sa_mask = sigset_all
+	if fn == funcPC(sighandler) {
+		fn = funcPC(sigtramp)
+	}
+	sa.sa_sigaction = fn
+	sigaction(i, &sa, nil)
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func setsigstack(i int32) {
+	throw("setsigstack")
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func getsig(i int32) uintptr {
+	var sa sigactiont
+	sigaction(i, nil, &sa)
+	if sa.sa_sigaction == funcPC(sigtramp) {
+		return funcPC(sighandler)
+	}
+	return sa.sa_sigaction
+}
+
+//go:nosplit
+func signalstack(s *stack) {
+	var st sigaltstackt
+	if s == nil {
+		st.ss_flags = _SS_DISABLE
+	} else {
+		st.ss_sp = s.lo
+		st.ss_size = s.hi - s.lo
+		st.ss_flags = 0
+	}
+	sigaltstack(&st, nil)
+}
+
+//go:nosplit
+//go:nowritebarrierrec
+func updatesigmask(m sigmask) {
+	var mask sigset
+	copy(mask.__bits[:], m[:])
+	sigprocmask(_SIG_SETMASK, &mask, nil)
+}
+
+func unblocksig(sig int32) {
+	var mask sigset
+	mask.__bits[(sig-1)/32] |= 1 << ((uint32(sig) - 1) & 31)
+	sigprocmask(_SIG_UNBLOCK, &mask, nil)
+}
diff --git a/src/runtime/os1_netbsd_386.go b/src/runtime/os_netbsd_386.go
similarity index 100%
rename from src/runtime/os1_netbsd_386.go
rename to src/runtime/os_netbsd_386.go
diff --git a/src/runtime/os1_netbsd_amd64.go b/src/runtime/os_netbsd_amd64.go
similarity index 100%
rename from src/runtime/os1_netbsd_amd64.go
rename to src/runtime/os_netbsd_amd64.go