diff options
Diffstat (limited to 'libgo/go/runtime/netpoll.go')
| -rw-r--r-- | libgo/go/runtime/netpoll.go | 70 |
1 files changed, 46 insertions, 24 deletions
diff --git a/libgo/go/runtime/netpoll.go b/libgo/go/runtime/netpoll.go index 1ce9808..d2fb775 100644 --- a/libgo/go/runtime/netpoll.go +++ b/libgo/go/runtime/netpoll.go @@ -2,7 +2,7 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -// +build aix darwin dragonfly freebsd hurd js,wasm linux nacl netbsd openbsd solaris windows +// +build aix darwin dragonfly freebsd hurd js,wasm linux netbsd openbsd solaris windows package runtime @@ -15,12 +15,26 @@ import ( //go:linkname netpoll // Integrated network poller (platform-independent part). -// A particular implementation (epoll/kqueue) must define the following functions: -// func netpollinit() // to initialize the poller -// func netpollopen(fd uintptr, pd *pollDesc) int32 // to arm edge-triggered notifications -// and associate fd with pd. -// An implementation must call the following function to denote that the pd is ready. -// func netpollready(gpp **g, pd *pollDesc, mode int32) +// A particular implementation (epoll/kqueue/port/AIX/Windows) +// must define the following functions: +// +// func netpollinit() +// Initialize the poller. Only called once. +// +// func netpollopen(fd uintptr, pd *pollDesc) int32 +// Arm edge-triggered notifications for fd. The pd argument is to pass +// back to netpollready when fd is ready. Return an errno value. +// +// func netpoll(delta int64) gList +// Poll the network. If delta < 0, block indefinitely. If delta == 0, +// poll without blocking. If delta > 0, block for up to delta nanoseconds. +// Return a list of goroutines built by calling netpollready. +// +// func netpollBreak() +// Wake up the network poller, assumed to be blocked in netpoll. +// +// func netpollIsPollDescriptor(fd uintptr) bool +// Reports whether fd is a file descriptor used by the poller. // pollDesc contains 2 binary semaphores, rg and wg, to park reader and writer // goroutines respectively. The semaphore can be in the following states: @@ -82,15 +96,27 @@ type pollCache struct { } var ( - netpollInited uint32 + netpollInitLock mutex + netpollInited uint32 + pollcache pollCache netpollWaiters uint32 ) //go:linkname poll_runtime_pollServerInit internal..z2fpoll.runtime_pollServerInit func poll_runtime_pollServerInit() { - netpollinit() - atomic.Store(&netpollInited, 1) + netpollGenericInit() +} + +func netpollGenericInit() { + if atomic.Load(&netpollInited) == 0 { + lock(&netpollInitLock) + if netpollInited == 0 { + netpollinit() + atomic.Store(&netpollInited, 1) + } + unlock(&netpollInitLock) + } } func netpollinited() bool { @@ -102,14 +128,7 @@ func netpollinited() bool { // poll_runtime_isPollServerDescriptor reports whether fd is a // descriptor being used by netpoll. func poll_runtime_isPollServerDescriptor(fd uintptr) bool { - fds := netpolldescriptor() - if GOOS != "aix" && GOOS != "hurd" { - return fd == fds - } else { - // AIX have a pipe in its netpoll implementation. - // Therefore, two fd are returned by netpolldescriptor using a mask. - return fd == fds&0xFFFF || fd == (fds>>16)&0xFFFF - } + return netpollIsPollDescriptor(fd) } //go:linkname poll_runtime_pollOpen internal..z2fpoll.runtime_pollOpen @@ -240,13 +259,12 @@ func poll_runtime_pollSetDeadline(ctx uintptr, d int64, mode int) { if pd.rt.f == nil { if pd.rd > 0 { pd.rt.f = rtf - pd.rt.when = pd.rd // Copy current seq into the timer arg. // Timer func will check the seq against current descriptor seq, // if they differ the descriptor was reused or timers were reset. pd.rt.arg = pd pd.rt.seq = pd.rseq - addtimer(&pd.rt) + resettimer(&pd.rt, pd.rd) } } else if pd.rd != rd0 || combo != combo0 { pd.rseq++ // invalidate current timers @@ -260,10 +278,9 @@ func poll_runtime_pollSetDeadline(ctx uintptr, d int64, mode int) { if pd.wt.f == nil { if pd.wd > 0 && !combo { pd.wt.f = netpollWriteDeadline - pd.wt.when = pd.wd pd.wt.arg = pd pd.wt.seq = pd.wseq - addtimer(&pd.wt) + resettimer(&pd.wt, pd.wd) } } else if pd.wd != wd0 || combo != combo0 { pd.wseq++ // invalidate current timers @@ -325,8 +342,13 @@ func poll_runtime_pollUnblock(ctx uintptr) { } } -// make pd ready, newly runnable goroutines (if any) are added to toRun. -// May run during STW, so write barriers are not allowed. +// netpollready is called by the platform-specific netpoll function. +// It declares that the fd associated with pd is ready for I/O. +// The toRun argument is used to build a list of goroutines to return +// from netpoll. The mode argument is 'r', 'w', or 'r'+'w' to indicate +// whether the fd is ready for reading or writing or both. +// +// This may run while the world is stopped, so write barriers are not allowed. //go:nowritebarrier func netpollready(toRun *gList, pd *pollDesc, mode int32) { var rg, wg *g |