1 files changed, 51 insertions, 0 deletions
diff --git a/src/runtime/os_openbsd_syscall.go b/src/runtime/os_openbsd_syscall.go
new file mode 100644
index 0000000..d784f76
--- /dev/null
+++ b/src/runtime/os_openbsd_syscall.go
@@ -0,0 +1,51 @@
+// 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.
+
+//go:build openbsd && mips64
+
+package runtime
+
+import (
+	"internal/abi"
+	"internal/goarch"
+	"unsafe"
+)
+
+//go:noescape
+func tfork(param *tforkt, psize uintptr, mm *m, gg *g, fn uintptr) int32
+
+// May run with m.p==nil, so write barriers are not allowed.
+//
+//go:nowritebarrier
+func newosproc(mp *m) {
+	stk := unsafe.Pointer(mp.g0.stack.hi)
+	if false {
+		print("newosproc stk=", stk, " m=", mp, " g=", mp.g0, " id=", mp.id, " ostk=", &mp, "\n")
+	}
+
+	// Stack pointer must point inside stack area (as marked with MAP_STACK),
+	// rather than at the top of it.
+	param := tforkt{
+		tf_tcb:   unsafe.Pointer(&mp.tls[0]),
+		tf_tid:   nil, // minit will record tid
+		tf_stack: uintptr(stk) - goarch.PtrSize,
+	}
+
+	var oset sigset
+	sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
+	ret := retryOnEAGAIN(func() int32 {
+		errno := tfork(&param, unsafe.Sizeof(param), mp, mp.g0, abi.FuncPCABI0(mstart))
+		// tfork returns negative errno
+		return -errno
+	})
+	sigprocmask(_SIG_SETMASK, &oset, nil)
+
+	if ret != 0 {
+		print("runtime: failed to create new OS thread (have ", mcount()-1, " already; errno=", ret, ")\n")
+		if ret == _EAGAIN {
+			println("runtime: may need to increase max user processes (ulimit -p)")
+		}
+		throw("runtime.newosproc")
+	}
+}