go/src/runtime/os3_solaris.go
Ian Lance Taylor efd93a412e runtime: minimize time between lockextra/unlockextra
This doesn't fix a bug, but may improve performance in programs that
have many concurrent calls from C to Go.  The old code made several
system calls between lockextra and unlockextra.  That could be happening
while another thread is spinning acquiring lockextra.  This changes the
code to not make any system calls while holding the lock.

Change-Id: I50576478e478670c3d6429ad4e1b7d80f98a19d8
Reviewed-on: https://go-review.googlesource.com/18548
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-14 05:55:43 +00:00

578 lines
16 KiB
Go

// 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"
//go:cgo_export_dynamic runtime.end _end
//go:cgo_export_dynamic runtime.etext _etext
//go:cgo_export_dynamic runtime.edata _edata
//go:cgo_import_dynamic libc____errno ___errno "libc.so"
//go:cgo_import_dynamic libc_clock_gettime clock_gettime "libc.so"
//go:cgo_import_dynamic libc_close close "libc.so"
//go:cgo_import_dynamic libc_exit exit "libc.so"
//go:cgo_import_dynamic libc_fstat fstat "libc.so"
//go:cgo_import_dynamic libc_getcontext getcontext "libc.so"
//go:cgo_import_dynamic libc_getrlimit getrlimit "libc.so"
//go:cgo_import_dynamic libc_kill kill "libc.so"
//go:cgo_import_dynamic libc_madvise madvise "libc.so"
//go:cgo_import_dynamic libc_malloc malloc "libc.so"
//go:cgo_import_dynamic libc_mmap mmap "libc.so"
//go:cgo_import_dynamic libc_munmap munmap "libc.so"
//go:cgo_import_dynamic libc_open open "libc.so"
//go:cgo_import_dynamic libc_pthread_attr_destroy pthread_attr_destroy "libc.so"
//go:cgo_import_dynamic libc_pthread_attr_getstack pthread_attr_getstack "libc.so"
//go:cgo_import_dynamic libc_pthread_attr_init pthread_attr_init "libc.so"
//go:cgo_import_dynamic libc_pthread_attr_setdetachstate pthread_attr_setdetachstate "libc.so"
//go:cgo_import_dynamic libc_pthread_attr_setstack pthread_attr_setstack "libc.so"
//go:cgo_import_dynamic libc_pthread_create pthread_create "libc.so"
//go:cgo_import_dynamic libc_raise raise "libc.so"
//go:cgo_import_dynamic libc_read read "libc.so"
//go:cgo_import_dynamic libc_select select "libc.so"
//go:cgo_import_dynamic libc_sched_yield sched_yield "libc.so"
//go:cgo_import_dynamic libc_sem_init sem_init "libc.so"
//go:cgo_import_dynamic libc_sem_post sem_post "libc.so"
//go:cgo_import_dynamic libc_sem_reltimedwait_np sem_reltimedwait_np "libc.so"
//go:cgo_import_dynamic libc_sem_wait sem_wait "libc.so"
//go:cgo_import_dynamic libc_setitimer setitimer "libc.so"
//go:cgo_import_dynamic libc_sigaction sigaction "libc.so"
//go:cgo_import_dynamic libc_sigaltstack sigaltstack "libc.so"
//go:cgo_import_dynamic libc_sigprocmask sigprocmask "libc.so"
//go:cgo_import_dynamic libc_sysconf sysconf "libc.so"
//go:cgo_import_dynamic libc_usleep usleep "libc.so"
//go:cgo_import_dynamic libc_write write "libc.so"
//go:linkname libc____errno libc____errno
//go:linkname libc_clock_gettime libc_clock_gettime
//go:linkname libc_close libc_close
//go:linkname libc_exit libc_exit
//go:linkname libc_fstat libc_fstat
//go:linkname libc_getcontext libc_getcontext
//go:linkname libc_getrlimit libc_getrlimit
//go:linkname libc_kill libc_kill
//go:linkname libc_madvise libc_madvise
//go:linkname libc_malloc libc_malloc
//go:linkname libc_mmap libc_mmap
//go:linkname libc_munmap libc_munmap
//go:linkname libc_open libc_open
//go:linkname libc_pthread_attr_destroy libc_pthread_attr_destroy
//go:linkname libc_pthread_attr_getstack libc_pthread_attr_getstack
//go:linkname libc_pthread_attr_init libc_pthread_attr_init
//go:linkname libc_pthread_attr_setdetachstate libc_pthread_attr_setdetachstate
//go:linkname libc_pthread_attr_setstack libc_pthread_attr_setstack
//go:linkname libc_pthread_create libc_pthread_create
//go:linkname libc_raise libc_raise
//go:linkname libc_read libc_read
//go:linkname libc_select libc_select
//go:linkname libc_sched_yield libc_sched_yield
//go:linkname libc_sem_init libc_sem_init
//go:linkname libc_sem_post libc_sem_post
//go:linkname libc_sem_reltimedwait_np libc_sem_reltimedwait_np
//go:linkname libc_sem_wait libc_sem_wait
//go:linkname libc_setitimer libc_setitimer
//go:linkname libc_sigaction libc_sigaction
//go:linkname libc_sigaltstack libc_sigaltstack
//go:linkname libc_sigprocmask libc_sigprocmask
//go:linkname libc_sysconf libc_sysconf
//go:linkname libc_usleep libc_usleep
//go:linkname libc_write libc_write
var (
libc____errno,
libc_clock_gettime,
libc_close,
libc_exit,
libc_fstat,
libc_getcontext,
libc_getrlimit,
libc_kill,
libc_madvise,
libc_malloc,
libc_mmap,
libc_munmap,
libc_open,
libc_pthread_attr_destroy,
libc_pthread_attr_getstack,
libc_pthread_attr_init,
libc_pthread_attr_setdetachstate,
libc_pthread_attr_setstack,
libc_pthread_create,
libc_raise,
libc_read,
libc_sched_yield,
libc_select,
libc_sem_init,
libc_sem_post,
libc_sem_reltimedwait_np,
libc_sem_wait,
libc_setitimer,
libc_sigaction,
libc_sigaltstack,
libc_sigprocmask,
libc_sysconf,
libc_usleep,
libc_write libcFunc
)
var sigset_all = sigset{[4]uint32{^uint32(0), ^uint32(0), ^uint32(0), ^uint32(0)}}
func getncpu() int32 {
n := int32(sysconf(__SC_NPROCESSORS_ONLN))
if n < 1 {
return 1
}
return n
}
func osinit() {
ncpu = getncpu()
}
func tstart_sysvicall()
// May run with m.p==nil, so write barriers are not allowed.
//go:nowritebarrier
func newosproc(mp *m, _ unsafe.Pointer) {
var (
attr pthreadattr
oset sigset
tid pthread
ret int32
size uint64
)
if pthread_attr_init(&attr) != 0 {
throw("pthread_attr_init")
}
if pthread_attr_setstack(&attr, 0, 0x200000) != 0 {
throw("pthread_attr_setstack")
}
if pthread_attr_getstack(&attr, unsafe.Pointer(&mp.g0.stack.hi), &size) != 0 {
throw("pthread_attr_getstack")
}
mp.g0.stack.lo = mp.g0.stack.hi - uintptr(size)
if pthread_attr_setdetachstate(&attr, _PTHREAD_CREATE_DETACHED) != 0 {
throw("pthread_attr_setdetachstate")
}
// Disable signals during create, so that the new thread starts
// with signals disabled. It will enable them in minit.
sigprocmask(_SIG_SETMASK, &sigset_all, &oset)
ret = pthread_create(&tid, &attr, funcPC(tstart_sysvicall), unsafe.Pointer(mp))
sigprocmask(_SIG_SETMASK, &oset, nil)
if ret != 0 {
print("runtime: failed to create new OS thread (have ", mcount(), " already; errno=", ret, ")\n")
throw("newosproc")
}
}
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
}
func miniterrno()
//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, can not allocate memory.
func minit() {
_g_ := getg()
asmcgocall(unsafe.Pointer(funcPC(miniterrno)), unsafe.Pointer(&libc____errno))
// Initialize signal handling
var st sigaltstackt
sigaltstack(nil, &st)
if st.ss_flags&_SS_DISABLE != 0 {
signalstack(&_g_.m.gsignal.stack)
_g_.m.newSigstack = true
} else {
// Use existing signal stack.
stsp := uintptr(unsafe.Pointer(st.ss_sp))
_g_.m.gsignal.stack.lo = stsp
_g_.m.gsignal.stack.hi = stsp + uintptr(st.ss_size)
_g_.m.gsignal.stackguard0 = stsp + _StackGuard
_g_.m.gsignal.stackguard1 = stsp + _StackGuard
_g_.m.gsignal.stackAlloc = uintptr(st.ss_size)
_g_.m.newSigstack = false
}
// 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.__sigbits[(i-1)/32] &^= 1 << ((uint32(i) - 1) & 31)
}
}
sigprocmask(_SIG_SETMASK, &nmask, nil)
}
// Called from dropm to undo the effect of an minit.
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()
//go:nosplit
//go:nowritebarrierrec
func setsig(i int32, fn uintptr, restart bool) {
var sa sigactiont
sa.sa_flags = _SA_SIGINFO | _SA_ONSTACK
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)
}
*((*uintptr)(unsafe.Pointer(&sa._funcptr))) = fn
sigaction(i, &sa, nil)
}
//go:nosplit
//go:nowritebarrierrec
func setsigstack(i int32) {
var sa sigactiont
sigaction(i, nil, &sa)
handler := *((*uintptr)(unsafe.Pointer(&sa._funcptr)))
if handler == 0 || handler == _SIG_DFL || handler == _SIG_IGN || sa.sa_flags&_SA_ONSTACK != 0 {
return
}
sa.sa_flags |= _SA_ONSTACK
sigaction(i, &sa, nil)
}
//go:nosplit
//go:nowritebarrierrec
func getsig(i int32) uintptr {
var sa sigactiont
sigaction(i, nil, &sa)
if *((*uintptr)(unsafe.Pointer(&sa._funcptr))) == funcPC(sigtramp) {
return funcPC(sighandler)
}
return *((*uintptr)(unsafe.Pointer(&sa._funcptr)))
}
//go:nosplit
func signalstack(s *stack) {
var st sigaltstackt
if s == nil {
st.ss_flags = _SS_DISABLE
} else {
st.ss_sp = (*byte)(unsafe.Pointer(s.lo))
st.ss_size = uint64(s.hi - s.lo)
st.ss_flags = 0
}
sigaltstack(&st, nil)
}
//go:nosplit
//go:nowritebarrierrec
func updatesigmask(m sigmask) {
var mask sigset
copy(mask.__sigbits[:], m[:])
sigprocmask(_SIG_SETMASK, &mask, nil)
}
func unblocksig(sig int32) {
var mask sigset
mask.__sigbits[(sig-1)/32] |= 1 << ((uint32(sig) - 1) & 31)
sigprocmask(_SIG_UNBLOCK, &mask, nil)
}
//go:nosplit
func semacreate(mp *m) {
if mp.waitsema != 0 {
return
}
var sem *semt
_g_ := getg()
// Call libc's malloc rather than malloc. This will
// allocate space on the C heap. We can't call malloc
// here because it could cause a deadlock.
_g_.m.libcall.fn = uintptr(unsafe.Pointer(&libc_malloc))
_g_.m.libcall.n = 1
memclr(unsafe.Pointer(&_g_.m.scratch), uintptr(len(_g_.m.scratch.v)))
_g_.m.scratch.v[0] = unsafe.Sizeof(*sem)
_g_.m.libcall.args = uintptr(unsafe.Pointer(&_g_.m.scratch))
asmcgocall(unsafe.Pointer(&asmsysvicall6), unsafe.Pointer(&_g_.m.libcall))
sem = (*semt)(unsafe.Pointer(_g_.m.libcall.r1))
if sem_init(sem, 0, 0) != 0 {
throw("sem_init")
}
mp.waitsema = uintptr(unsafe.Pointer(sem))
}
//go:nosplit
func semasleep(ns int64) int32 {
_m_ := getg().m
if ns >= 0 {
_m_.ts.tv_sec = ns / 1000000000
_m_.ts.tv_nsec = ns % 1000000000
_m_.libcall.fn = uintptr(unsafe.Pointer(&libc_sem_reltimedwait_np))
_m_.libcall.n = 2
memclr(unsafe.Pointer(&_m_.scratch), uintptr(len(_m_.scratch.v)))
_m_.scratch.v[0] = _m_.waitsema
_m_.scratch.v[1] = uintptr(unsafe.Pointer(&_m_.ts))
_m_.libcall.args = uintptr(unsafe.Pointer(&_m_.scratch))
asmcgocall(unsafe.Pointer(&asmsysvicall6), unsafe.Pointer(&_m_.libcall))
if *_m_.perrno != 0 {
if *_m_.perrno == _ETIMEDOUT || *_m_.perrno == _EAGAIN || *_m_.perrno == _EINTR {
return -1
}
throw("sem_reltimedwait_np")
}
return 0
}
for {
_m_.libcall.fn = uintptr(unsafe.Pointer(&libc_sem_wait))
_m_.libcall.n = 1
memclr(unsafe.Pointer(&_m_.scratch), uintptr(len(_m_.scratch.v)))
_m_.scratch.v[0] = _m_.waitsema
_m_.libcall.args = uintptr(unsafe.Pointer(&_m_.scratch))
asmcgocall(unsafe.Pointer(&asmsysvicall6), unsafe.Pointer(&_m_.libcall))
if _m_.libcall.r1 == 0 {
break
}
if *_m_.perrno == _EINTR {
continue
}
throw("sem_wait")
}
return 0
}
//go:nosplit
func semawakeup(mp *m) {
if sem_post((*semt)(unsafe.Pointer(mp.waitsema))) != 0 {
throw("sem_post")
}
}
//go:nosplit
func closefd(fd int32) int32 {
return int32(sysvicall1(&libc_close, uintptr(fd)))
}
//go:nosplit
func exit(r int32) {
sysvicall1(&libc_exit, uintptr(r))
}
//go:nosplit
func getcontext(context *ucontext) /* int32 */ {
sysvicall1(&libc_getcontext, uintptr(unsafe.Pointer(context)))
}
//go:nosplit
func madvise(addr unsafe.Pointer, n uintptr, flags int32) {
sysvicall3(&libc_madvise, uintptr(addr), uintptr(n), uintptr(flags))
}
//go:nosplit
func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uint32) unsafe.Pointer {
return unsafe.Pointer(sysvicall6(&libc_mmap, uintptr(addr), uintptr(n), uintptr(prot), uintptr(flags), uintptr(fd), uintptr(off)))
}
//go:nosplit
func munmap(addr unsafe.Pointer, n uintptr) {
sysvicall2(&libc_munmap, uintptr(addr), uintptr(n))
}
func nanotime1()
//go:nosplit
func nanotime() int64 {
return int64(sysvicall0((*libcFunc)(unsafe.Pointer(funcPC(nanotime1)))))
}
//go:nosplit
func open(path *byte, mode, perm int32) int32 {
return int32(sysvicall3(&libc_open, uintptr(unsafe.Pointer(path)), uintptr(mode), uintptr(perm)))
}
func pthread_attr_destroy(attr *pthreadattr) int32 {
return int32(sysvicall1(&libc_pthread_attr_destroy, uintptr(unsafe.Pointer(attr))))
}
func pthread_attr_getstack(attr *pthreadattr, addr unsafe.Pointer, size *uint64) int32 {
return int32(sysvicall3(&libc_pthread_attr_getstack, uintptr(unsafe.Pointer(attr)), uintptr(addr), uintptr(unsafe.Pointer(size))))
}
func pthread_attr_init(attr *pthreadattr) int32 {
return int32(sysvicall1(&libc_pthread_attr_init, uintptr(unsafe.Pointer(attr))))
}
func pthread_attr_setdetachstate(attr *pthreadattr, state int32) int32 {
return int32(sysvicall2(&libc_pthread_attr_setdetachstate, uintptr(unsafe.Pointer(attr)), uintptr(state)))
}
func pthread_attr_setstack(attr *pthreadattr, addr uintptr, size uint64) int32 {
return int32(sysvicall3(&libc_pthread_attr_setstack, uintptr(unsafe.Pointer(attr)), uintptr(addr), uintptr(size)))
}
func pthread_create(thread *pthread, attr *pthreadattr, fn uintptr, arg unsafe.Pointer) int32 {
return int32(sysvicall4(&libc_pthread_create, uintptr(unsafe.Pointer(thread)), uintptr(unsafe.Pointer(attr)), uintptr(fn), uintptr(arg)))
}
//go:nosplit
//go:nowritebarrierrec
func raise(sig int32) /* int32 */ {
sysvicall1(&libc_raise, uintptr(sig))
}
func raiseproc(sig int32) /* int32 */ {
pid := sysvicall0(&libc_getpid)
sysvicall2(&libc_kill, pid, uintptr(sig))
}
//go:nosplit
func read(fd int32, buf unsafe.Pointer, nbyte int32) int32 {
return int32(sysvicall3(&libc_read, uintptr(fd), uintptr(buf), uintptr(nbyte)))
}
//go:nosplit
func sem_init(sem *semt, pshared int32, value uint32) int32 {
return int32(sysvicall3(&libc_sem_init, uintptr(unsafe.Pointer(sem)), uintptr(pshared), uintptr(value)))
}
//go:nosplit
func sem_post(sem *semt) int32 {
return int32(sysvicall1(&libc_sem_post, uintptr(unsafe.Pointer(sem))))
}
//go:nosplit
func sem_reltimedwait_np(sem *semt, timeout *timespec) int32 {
return int32(sysvicall2(&libc_sem_reltimedwait_np, uintptr(unsafe.Pointer(sem)), uintptr(unsafe.Pointer(timeout))))
}
//go:nosplit
func sem_wait(sem *semt) int32 {
return int32(sysvicall1(&libc_sem_wait, uintptr(unsafe.Pointer(sem))))
}
func setitimer(which int32, value *itimerval, ovalue *itimerval) /* int32 */ {
sysvicall3(&libc_setitimer, uintptr(which), uintptr(unsafe.Pointer(value)), uintptr(unsafe.Pointer(ovalue)))
}
//go:nosplit
//go:nowritebarrierrec
func sigaction(sig int32, act *sigactiont, oact *sigactiont) /* int32 */ {
sysvicall3(&libc_sigaction, uintptr(sig), uintptr(unsafe.Pointer(act)), uintptr(unsafe.Pointer(oact)))
}
//go:nosplit
//go:nowritebarrierrec
func sigaltstack(ss *sigaltstackt, oss *sigaltstackt) /* int32 */ {
sysvicall2(&libc_sigaltstack, uintptr(unsafe.Pointer(ss)), uintptr(unsafe.Pointer(oss)))
}
//go:nosplit
//go:nowritebarrierrec
//go:noescape
func sigprocmask(how int32, set *sigset, oset *sigset) /* int32 */ {
sysvicall3(&libc_sigprocmask, uintptr(how), uintptr(unsafe.Pointer(set)), uintptr(unsafe.Pointer(oset)))
}
func sysconf(name int32) int64 {
return int64(sysvicall1(&libc_sysconf, uintptr(name)))
}
func usleep1(uint32)
//go:nosplit
func usleep(µs uint32) {
usleep1(µs)
}
//go:nosplit
func write(fd uintptr, buf unsafe.Pointer, nbyte int32) int32 {
return int32(sysvicall3(&libc_write, uintptr(fd), uintptr(buf), uintptr(nbyte)))
}
func osyield1()
//go:nosplit
func osyield() {
_g_ := getg()
// Check the validity of m because we might be called in cgo callback
// path early enough where there isn't a m available yet.
if _g_ != nil && _g_.m != nil {
sysvicall0(&libc_sched_yield)
return
}
osyield1()
}