libgo/go/runtime/os_freebsd.go

   1 // Copyright 2011 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package runtime
   6
   7 import (
   8         "unsafe"
   9 )
  10
  11 type mOS struct {
  12         unused byte
  13 }
  14
  15 //go:noescape
  16 //extern _umtx_op
  17 func sys_umtx_op(addr *uint32, mode int32, val uint32, uaddr1 uinptr, ts *umtx_time) int32
  18
  19 // FreeBSD's umtx_op syscall is effectively the same as Linux's futex, and
  20 // thus the code is largely similar. See Linux implementation
  21 // and lock_futex.go for comments.
  22
  23 //go:nosplit
  24 func futexsleep(addr *uint32, val uint32, ns int64) {
  25         systemstack(func() {
  26                 futexsleep1(addr, val, ns)
  27         })
  28 }
  29
  30 func futexsleep1(addr *uint32, val uint32, ns int64) {
  31         var utp *umtx_time
  32         if ns >= 0 {
  33                 var ut umtx_time
  34                 ut._clockid = _CLOCK_MONOTONIC
  35                 ut._timeout.set_sec(int64(timediv(ns, 1000000000, (*int32)(unsafe.Pointer(&ut._timeout.tv_nsec)))))
  36                 utp = &ut
  37         }
  38         ret := sys_umtx_op(addr, _UMTX_OP_WAIT_UINT_PRIVATE, val, unsafe.Sizeof(*utp), utp)
  39         if ret >= 0 || ret == -_EINTR {
  40                 return
  41         }
  42         print("umtx_wait addr=", addr, " val=", val, " ret=", ret, "\n")
  43         *(*int32)(unsafe.Pointer(uintptr(0x1005))) = 0x1005
  44 }
  45
  46 //go:nosplit
  47 func futexwakeup(addr *uint32, cnt uint32) {
  48         ret := sys_umtx_op(addr, _UMTX_OP_WAKE_PRIVATE, cnt, 0, nil)
  49         if ret >= 0 {
  50                 return
  51         }
  52
  53         systemstack(func() {
  54                 print("umtx_wake_addr=", addr, " ret=", ret, "\n")
  55         })
  56 }