c0401cf78c
Remove the old locking code written in C.
Add a shell script mkrsysinfo.sh to generate the runtime_sysinfo.go
file, so that we can get Go copies of the system time structures and
other types.
Tweak the compiler so that when compiling the runtime package the
address operator does not cause local variables to escape. When the gc
compiler compiles the runtime, an escaping local variable is treated as
an error. We should implement that, instead of this change, when escape
analysis is turned on.
Tweak the compiler so that the generated C header does not include names
that start with an underscore followed by a non-upper-case letter,
except for the special cases of _defer and _panic. Otherwise we
translate C types to Go in runtime_sysinfo.go and then generate those Go
types back as C types in runtime.inc, which is useless and painful for
the C code.
Change entersyscall and friends to take a dummy argument, as the gc
versions do, to simplify calls from the shared code.
Reviewed-on: https://go-review.googlesource.com/30079
From-SVN: r240657
86 lines
1.7 KiB
Go
86 lines
1.7 KiB
Go
// Copyright 2011 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package runtime
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import "unsafe"
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type mOS struct {
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waitsema uintptr // semaphore for parking on locks
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}
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//extern malloc
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func libc_malloc(uintptr) unsafe.Pointer
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//go:noescape
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//extern sem_init
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func sem_init(sem *semt, pshared int32, value uint32) int32
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//go:noescape
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//extern sem_wait
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func sem_wait(sem *semt) int32
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//go:noescape
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//extern sem_post
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func sem_post(sem *semt) int32
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//go:noescape
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//extern sem_reltimedwait_np
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func sem_reltimedwait_np(sem *semt, timeout *timespec) int32
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//go:nosplit
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func semacreate(mp *m) {
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if mp.mos.waitsema != 0 {
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return
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}
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var sem *semt
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// Call libc's malloc rather than malloc. This will
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// allocate space on the C heap. We can't call malloc
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// here because it could cause a deadlock.
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sem = (*semt)(libc_malloc(unsafe.Sizeof(*sem)))
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if sem_init(sem, 0, 0) != 0 {
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throw("sem_init")
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}
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mp.mos.waitsema = uintptr(unsafe.Pointer(sem))
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}
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//go:nosplit
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func semasleep(ns int64) int32 {
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_m_ := getg().m
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if ns >= 0 {
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var ts timespec
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ts.set_sec(ns / 1000000000)
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ts.set_nsec(int32(ns % 1000000000))
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if sem_reltimedwait_np((*semt)(unsafe.Pointer(_m_.mos.waitsema)), &ts) != 0 {
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err := errno()
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if err == _ETIMEDOUT || err == _EAGAIN || err == _EINTR {
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return -1
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}
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throw("sem_reltimedwait_np")
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}
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return 0
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}
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for {
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r1 := sem_wait((*semt)(unsafe.Pointer(_m_.mos.waitsema)))
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if r1 == 0 {
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break
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}
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if errno() == _EINTR {
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continue
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}
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throw("sem_wait")
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}
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return 0
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}
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//go:nosplit
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func semawakeup(mp *m) {
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if sem_post((*semt)(unsafe.Pointer(mp.mos.waitsema))) != 0 {
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throw("sem_post")
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}
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}
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