| // Copyright 2014 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" |
| "runtime/internal/sys" |
| "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 |
| |
| // From <sys/lwp.h> |
| _LWP_DETACHED = 0x00000040 |
| |
| _EAGAIN = 35 |
| ) |
| |
| type mOS struct { |
| waitsemacount uint32 |
| } |
| |
| //go:noescape |
| func setitimer(mode int32, new, old *itimerval) |
| |
| //go:noescape |
| func sigaction(sig uint32, new, old *sigactiont) |
| |
| //go:noescape |
| func sigaltstack(new, old *stackt) |
| |
| //go:noescape |
| func sigprocmask(how int32, new, old *sigset) |
| |
| //go:noescape |
| func sysctl(mib *uint32, miblen uint32, out *byte, size *uintptr, dst *byte, ndst uintptr) int32 |
| |
| func lwp_tramp() |
| |
| func raise(sig uint32) |
| func raiseproc(sig uint32) |
| |
| //go:noescape |
| func getcontext(ctxt unsafe.Pointer) |
| |
| //go:noescape |
| func lwp_create(ctxt unsafe.Pointer, flags uintptr, lwpid unsafe.Pointer) int32 |
| |
| //go:noescape |
| func lwp_park(clockid, flags int32, ts *timespec, unpark int32, hint, unparkhint unsafe.Pointer) int32 |
| |
| //go:noescape |
| func lwp_unpark(lwp int32, hint unsafe.Pointer) int32 |
| |
| 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 |
| |
| _TIMER_RELTIME = 0 |
| _TIMER_ABSTIME = 1 |
| ) |
| |
| 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 |
| _HW_PAGESIZE = 7 |
| ) |
| |
| 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 |
| } |
| |
| func getPageSize() uintptr { |
| mib := [2]uint32{_CTL_HW, _HW_PAGESIZE} |
| out := uint32(0) |
| nout := unsafe.Sizeof(out) |
| ret := sysctl(&mib[0], 2, (*byte)(unsafe.Pointer(&out)), &nout, nil, 0) |
| if ret >= 0 { |
| return uintptr(out) |
| } |
| return 0 |
| } |
| |
| //go:nosplit |
| func semacreate(mp *m) { |
| } |
| |
| //go:nosplit |
| func semasleep(ns int64) int32 { |
| _g_ := getg() |
| |
| // Compute sleep deadline. |
| var tsp *timespec |
| var ts timespec |
| if ns >= 0 { |
| var nsec int32 |
| 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(_CLOCK_MONOTONIC, _TIMER_RELTIME, tsp, 0, unsafe.Pointer(&_g_.m.waitsemacount), nil) |
| if ret == _ETIMEDOUT { |
| return -1 |
| } else if ret == _EINTR && ns >= 0 { |
| // Avoid sleeping forever if we keep getting |
| // interrupted (for example by the profiling |
| // timer). It would be if tsp upon return had the |
| // remaining time to sleep, but this is good enough. |
| var nsec int32 |
| ns /= 2 |
| ts.set_sec(timediv(ns, 1000000000, &nsec)) |
| ts.set_nsec(nsec) |
| } |
| } |
| } |
| |
| //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_SIGMASK does not seem to work here. |
| // It would be nice if _UC_SIGMASK and _UC_STACK |
| // worked so that we could do all the work setting |
| // the sigmask and the stack here, instead of setting |
| // the mask here and the stack in netbsdMstart. |
| // For now do the blocking manually. |
| uc.uc_flags = _UC_SIGMASK | _UC_CPU |
| uc.uc_link = nil |
| uc.uc_sigmask = sigset_all |
| |
| var oset sigset |
| sigprocmask(_SIG_SETMASK, &sigset_all, &oset) |
| |
| lwp_mcontext_init(&uc.uc_mcontext, stk, mp, mp.g0, funcPC(netbsdMstart)) |
| |
| ret := lwp_create(unsafe.Pointer(&uc), _LWP_DETACHED, unsafe.Pointer(&mp.procid)) |
| 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") |
| } |
| } |
| |
| // 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() { |
| st := stackt{ss_flags: _SS_DISABLE} |
| sigaltstack(&st, nil) |
| mstart() |
| } |
| |
| func osinit() { |
| ncpu = getncpu() |
| if physPageSize == 0 { |
| physPageSize = getPageSize() |
| } |
| } |
| |
| 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 |
| } |
| |
| // 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()) |
| |
| // 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 |
| |
| minitSignalMask() |
| } |
| |
| // Called from dropm to undo the effect of an minit. |
| //go:nosplit |
| func unminit() { |
| unminitSignals() |
| } |
| |
| func sigtramp() |
| |
| type sigactiont struct { |
| sa_sigaction uintptr |
| sa_mask sigset |
| sa_flags int32 |
| } |
| |
| //go:nosplit |
| //go:nowritebarrierrec |
| func setsig(i uint32, fn uintptr) { |
| var sa sigactiont |
| sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK | _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 uint32) { |
| throw("setsigstack") |
| } |
| |
| //go:nosplit |
| //go:nowritebarrierrec |
| func getsig(i uint32) uintptr { |
| var sa sigactiont |
| sigaction(i, nil, &sa) |
| return sa.sa_sigaction |
| } |
| |
| // setSignaltstackSP sets the ss_sp field of a stackt. |
| //go:nosplit |
| func setSignalstackSP(s *stackt, sp uintptr) { |
| s.ss_sp = sp |
| } |
| |
| //go:nosplit |
| //go:nowritebarrierrec |
| func sigaddset(mask *sigset, i int) { |
| mask.__bits[(i-1)/32] |= 1 << ((uint32(i) - 1) & 31) |
| } |
| |
| func sigdelset(mask *sigset, i int) { |
| mask.__bits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31) |
| } |
| |
| func (c *sigctxt) fixsigcode(sig uint32) { |
| } |
| |
| func sysargs(argc int32, argv **byte) { |
| n := argc + 1 |
| |
| // skip over argv, envp to get to auxv |
| for argv_index(argv, n) != nil { |
| n++ |
| } |
| |
| // skip NULL separator |
| n++ |
| |
| // now argv+n is auxv |
| auxv := (*[1 << 28]uintptr)(add(unsafe.Pointer(argv), uintptr(n)*sys.PtrSize)) |
| sysauxv(auxv[:]) |
| } |
| |
| const ( |
| _AT_NULL = 0 // Terminates the vector |
| _AT_PAGESZ = 6 // Page size in bytes |
| ) |
| |
| func sysauxv(auxv []uintptr) { |
| for i := 0; auxv[i] != _AT_NULL; i += 2 { |
| tag, val := auxv[i], auxv[i+1] |
| switch tag { |
| case _AT_PAGESZ: |
| physPageSize = val |
| } |
| } |
| } |