| // 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 ( |
| "internal/abi" |
| "internal/goarch" |
| "unsafe" |
| ) |
| |
| type mOS struct{} |
| |
| //go:noescape |
| func thr_new(param *thrparam, size int32) int32 |
| |
| //go:noescape |
| func sigaltstack(new, old *stackt) |
| |
| //go:noescape |
| func sigprocmask(how int32, new, old *sigset) |
| |
| //go:noescape |
| func setitimer(mode int32, new, old *itimerval) |
| |
| //go:noescape |
| func sysctl(mib *uint32, miblen uint32, out *byte, size *uintptr, dst *byte, ndst uintptr) int32 |
| |
| func raiseproc(sig uint32) |
| |
| func thr_self() thread |
| func thr_kill(tid thread, sig int) |
| |
| //go:noescape |
| func sys_umtx_op(addr *uint32, mode int32, val uint32, uaddr1 uintptr, ut *umtx_time) int32 |
| |
| func osyield() |
| |
| //go:nosplit |
| func osyield_no_g() { |
| osyield() |
| } |
| |
| func kqueue() int32 |
| |
| //go:noescape |
| func kevent(kq int32, ch *keventt, nch int32, ev *keventt, nev int32, ts *timespec) int32 |
| |
| func pipe() (r, w int32, errno int32) |
| func pipe2(flags int32) (r, w int32, errno int32) |
| func closeonexec(fd int32) |
| func setNonblock(fd int32) |
| |
| // From FreeBSD's <sys/sysctl.h> |
| const ( |
| _CTL_HW = 6 |
| _HW_PAGESIZE = 7 |
| ) |
| |
| var sigset_all = sigset{[4]uint32{^uint32(0), ^uint32(0), ^uint32(0), ^uint32(0)}} |
| |
| // Undocumented numbers from FreeBSD's lib/libc/gen/sysctlnametomib.c. |
| const ( |
| _CTL_QUERY = 0 |
| _CTL_QUERY_MIB = 3 |
| ) |
| |
| // sysctlnametomib fill mib with dynamically assigned sysctl entries of name, |
| // return count of effected mib slots, return 0 on error. |
| func sysctlnametomib(name []byte, mib *[_CTL_MAXNAME]uint32) uint32 { |
| oid := [2]uint32{_CTL_QUERY, _CTL_QUERY_MIB} |
| miblen := uintptr(_CTL_MAXNAME) |
| if sysctl(&oid[0], 2, (*byte)(unsafe.Pointer(mib)), &miblen, (*byte)(unsafe.Pointer(&name[0])), (uintptr)(len(name))) < 0 { |
| return 0 |
| } |
| miblen /= unsafe.Sizeof(uint32(0)) |
| if miblen <= 0 { |
| return 0 |
| } |
| return uint32(miblen) |
| } |
| |
| const ( |
| _CPU_CURRENT_PID = -1 // Current process ID. |
| ) |
| |
| //go:noescape |
| func cpuset_getaffinity(level int, which int, id int64, size int, mask *byte) int32 |
| |
| //go:systemstack |
| func getncpu() int32 { |
| // Use a large buffer for the CPU mask. We're on the system |
| // stack, so this is fine, and we can't allocate memory for a |
| // dynamically-sized buffer at this point. |
| const maxCPUs = 64 * 1024 |
| var mask [maxCPUs / 8]byte |
| var mib [_CTL_MAXNAME]uint32 |
| |
| // According to FreeBSD's /usr/src/sys/kern/kern_cpuset.c, |
| // cpuset_getaffinity return ERANGE when provided buffer size exceed the limits in kernel. |
| // Querying kern.smp.maxcpus to calculate maximum buffer size. |
| // See https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=200802 |
| |
| // Variable kern.smp.maxcpus introduced at Dec 23 2003, revision 123766, |
| // with dynamically assigned sysctl entries. |
| miblen := sysctlnametomib([]byte("kern.smp.maxcpus"), &mib) |
| if miblen == 0 { |
| return 1 |
| } |
| |
| // Query kern.smp.maxcpus. |
| dstsize := uintptr(4) |
| maxcpus := uint32(0) |
| if sysctl(&mib[0], miblen, (*byte)(unsafe.Pointer(&maxcpus)), &dstsize, nil, 0) != 0 { |
| return 1 |
| } |
| |
| maskSize := int(maxcpus+7) / 8 |
| if maskSize < goarch.PtrSize { |
| maskSize = goarch.PtrSize |
| } |
| if maskSize > len(mask) { |
| maskSize = len(mask) |
| } |
| |
| if cpuset_getaffinity(_CPU_LEVEL_WHICH, _CPU_WHICH_PID, _CPU_CURRENT_PID, |
| maskSize, (*byte)(unsafe.Pointer(&mask[0]))) != 0 { |
| return 1 |
| } |
| n := int32(0) |
| for _, v := range mask[:maskSize] { |
| for v != 0 { |
| n += int32(v & 1) |
| v >>= 1 |
| } |
| } |
| if n == 0 { |
| return 1 |
| } |
| return n |
| } |
| |
| 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 |
| } |
| |
| // FreeBSD's umtx_op syscall is effectively the same as Linux's futex, and |
| // thus the code is largely similar. See Linux implementation |
| // and lock_futex.go for comments. |
| |
| //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 utp *umtx_time |
| if ns >= 0 { |
| var ut umtx_time |
| ut._clockid = _CLOCK_MONOTONIC |
| ut._timeout.setNsec(ns) |
| utp = &ut |
| } |
| ret := sys_umtx_op(addr, _UMTX_OP_WAIT_UINT_PRIVATE, val, unsafe.Sizeof(*utp), utp) |
| if ret >= 0 || ret == -_EINTR || ret == -_ETIMEDOUT { |
| return |
| } |
| print("umtx_wait addr=", addr, " val=", val, " ret=", ret, "\n") |
| *(*int32)(unsafe.Pointer(uintptr(0x1005))) = 0x1005 |
| } |
| |
| //go:nosplit |
| func futexwakeup(addr *uint32, cnt uint32) { |
| ret := sys_umtx_op(addr, _UMTX_OP_WAKE_PRIVATE, cnt, 0, nil) |
| if ret >= 0 { |
| return |
| } |
| |
| systemstack(func() { |
| print("umtx_wake_addr=", addr, " ret=", ret, "\n") |
| }) |
| } |
| |
| func thr_start() |
| |
| // 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, " thr_start=", abi.FuncPCABI0(thr_start), " id=", mp.id, " ostk=", &mp, "\n") |
| } |
| |
| param := thrparam{ |
| start_func: abi.FuncPCABI0(thr_start), |
| arg: unsafe.Pointer(mp), |
| stack_base: mp.g0.stack.lo, |
| stack_size: uintptr(stk) - mp.g0.stack.lo, |
| child_tid: nil, // minit will record tid |
| parent_tid: nil, |
| tls_base: unsafe.Pointer(&mp.tls[0]), |
| tls_size: unsafe.Sizeof(mp.tls), |
| } |
| |
| var oset sigset |
| sigprocmask(_SIG_SETMASK, &sigset_all, &oset) |
| ret := thr_new(¶m, int32(unsafe.Sizeof(param))) |
| sigprocmask(_SIG_SETMASK, &oset, nil) |
| if ret < 0 { |
| print("runtime: failed to create new OS thread (have ", mcount(), " already; errno=", -ret, ")\n") |
| throw("newosproc") |
| } |
| } |
| |
| // Version of newosproc that doesn't require a valid G. |
| //go:nosplit |
| func newosproc0(stacksize uintptr, fn unsafe.Pointer) { |
| stack := sysAlloc(stacksize, &memstats.stacks_sys) |
| if stack == nil { |
| write(2, unsafe.Pointer(&failallocatestack[0]), int32(len(failallocatestack))) |
| exit(1) |
| } |
| // This code "knows" it's being called once from the library |
| // initialization code, and so it's using the static m0 for the |
| // tls and procid (thread) pointers. thr_new() requires the tls |
| // pointers, though the tid pointers can be nil. |
| // However, newosproc0 is currently unreachable because builds |
| // utilizing c-shared/c-archive force external linking. |
| param := thrparam{ |
| start_func: uintptr(fn), |
| arg: nil, |
| stack_base: uintptr(stack), //+stacksize? |
| stack_size: stacksize, |
| child_tid: nil, // minit will record tid |
| parent_tid: nil, |
| tls_base: unsafe.Pointer(&m0.tls[0]), |
| tls_size: unsafe.Sizeof(m0.tls), |
| } |
| |
| var oset sigset |
| sigprocmask(_SIG_SETMASK, &sigset_all, &oset) |
| ret := thr_new(¶m, int32(unsafe.Sizeof(param))) |
| sigprocmask(_SIG_SETMASK, &oset, nil) |
| if ret < 0 { |
| write(2, unsafe.Pointer(&failthreadcreate[0]), int32(len(failthreadcreate))) |
| exit(1) |
| } |
| } |
| |
| var failallocatestack = []byte("runtime: failed to allocate stack for the new OS thread\n") |
| var failthreadcreate = []byte("runtime: failed to create new OS thread\n") |
| |
| // Called to do synchronous initialization of Go code built with |
| // -buildmode=c-archive or -buildmode=c-shared. |
| // None of the Go runtime is initialized. |
| //go:nosplit |
| //go:nowritebarrierrec |
| func libpreinit() { |
| initsig(true) |
| } |
| |
| 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() { |
| getg().m.procid = uint64(thr_self()) |
| |
| // On FreeBSD before about April 2017 there was a bug such |
| // that calling execve from a thread other than the main |
| // thread did not reset the signal stack. That would confuse |
| // minitSignals, which calls minitSignalStack, which checks |
| // whether there is currently a signal stack and uses it if |
| // present. To avoid this confusion, explicitly disable the |
| // signal stack on the main thread when not running in a |
| // library. This can be removed when we are confident that all |
| // FreeBSD users are running a patched kernel. See issue #15658. |
| if gp := getg(); !isarchive && !islibrary && gp.m == &m0 && gp == gp.m.g0 { |
| st := stackt{ss_flags: _SS_DISABLE} |
| sigaltstack(&st, nil) |
| } |
| |
| minitSignals() |
| } |
| |
| // Called from dropm to undo the effect of an minit. |
| //go:nosplit |
| func unminit() { |
| unminitSignals() |
| } |
| |
| // Called from exitm, but not from drop, to undo the effect of thread-owned |
| // resources in minit, semacreate, or elsewhere. Do not take locks after calling this. |
| func mdestroy(mp *m) { |
| } |
| |
| func sigtramp() |
| |
| type sigactiont struct { |
| sa_handler uintptr |
| sa_flags int32 |
| sa_mask sigset |
| } |
| |
| // See os_freebsd2.go, os_freebsd_amd64.go for setsig function |
| |
| //go:nosplit |
| //go:nowritebarrierrec |
| func setsigstack(i uint32) { |
| var sa sigactiont |
| sigaction(i, nil, &sa) |
| if sa.sa_flags&_SA_ONSTACK != 0 { |
| return |
| } |
| sa.sa_flags |= _SA_ONSTACK |
| sigaction(i, &sa, nil) |
| } |
| |
| //go:nosplit |
| //go:nowritebarrierrec |
| func getsig(i uint32) uintptr { |
| var sa sigactiont |
| sigaction(i, nil, &sa) |
| return sa.sa_handler |
| } |
| |
| // 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) |
| } |
| |
| //go:nosplit |
| func (c *sigctxt) fixsigcode(sig uint32) { |
| } |
| |
| func setProcessCPUProfiler(hz int32) { |
| setProcessCPUProfilerTimer(hz) |
| } |
| |
| func setThreadCPUProfiler(hz int32) { |
| setThreadCPUProfilerHz(hz) |
| } |
| |
| //go:nosplit |
| func validSIGPROF(mp *m, c *sigctxt) bool { |
| return true |
| } |
| |
| 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)*goarch.PtrSize)) |
| sysauxv(auxv[:]) |
| } |
| |
| const ( |
| _AT_NULL = 0 // Terminates the vector |
| _AT_PAGESZ = 6 // Page size in bytes |
| _AT_TIMEKEEP = 22 // Pointer to timehands. |
| _AT_HWCAP = 25 // CPU feature flags |
| _AT_HWCAP2 = 26 // CPU feature flags 2 |
| ) |
| |
| func sysauxv(auxv []uintptr) { |
| for i := 0; auxv[i] != _AT_NULL; i += 2 { |
| tag, val := auxv[i], auxv[i+1] |
| switch tag { |
| // _AT_NCPUS from auxv shouldn't be used due to golang.org/issue/15206 |
| case _AT_PAGESZ: |
| physPageSize = val |
| case _AT_TIMEKEEP: |
| timekeepSharedPage = (*vdsoTimekeep)(unsafe.Pointer(val)) |
| } |
| |
| archauxv(tag, val) |
| } |
| } |
| |
| // sysSigaction calls the sigaction system call. |
| //go:nosplit |
| func sysSigaction(sig uint32, new, old *sigactiont) { |
| // Use system stack to avoid split stack overflow on amd64 |
| if asmSigaction(uintptr(sig), new, old) != 0 { |
| systemstack(func() { |
| throw("sigaction failed") |
| }) |
| } |
| } |
| |
| // asmSigaction is implemented in assembly. |
| //go:noescape |
| func asmSigaction(sig uintptr, new, old *sigactiont) int32 |
| |
| // raise sends a signal to the calling thread. |
| // |
| // It must be nosplit because it is used by the signal handler before |
| // it definitely has a Go stack. |
| // |
| //go:nosplit |
| func raise(sig uint32) { |
| thr_kill(thr_self(), int(sig)) |
| } |
| |
| func signalM(mp *m, sig int) { |
| thr_kill(thread(mp.procid), sig) |
| } |