qbit/go
1
0
Fork 0
mirror of https://github.com/golang/go synced 2024-11-17 00:14:50 -07:00
Code Releases Activity

runtime: use eventfd as the event wait/notify mechanism for epoll

Browse Source 
Fixes #65443

Change-Id: I9ad4689b36e87ee930d35a38322a8797896483b4
Reviewed-on: https://go-review.googlesource.com/c/go/+/560615
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Than McIntosh <thanm@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Jorropo <jorropo.pgm@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
This commit is contained in:
Andy Pan 2024-02-02 11:22:57 +08:00 committed by Gopher Robot
parent c4d55ab912
commit d068c2cb62
13 changed files with 58 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
src/runtime/internal/syscall/defs_linux.go Normal file
View File

@ -0,0 +1,9 @@
// Copyright 2024 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 syscall
const (
EFD_CLOEXEC = 0x80000
)

2
src/runtime/internal/syscall/defs_linux_386.go
View File

@ -10,6 +10,7 @@ const (
SYS_EPOLL_PWAIT = 319
SYS_EPOLL_CREATE1 = 329
SYS_EPOLL_PWAIT2 = 441
SYS_EVENTFD2 = 328
EPOLLIN = 0x1
EPOLLOUT = 0x4
@ -21,6 +22,7 @@ const (
EPOLL_CTL_ADD = 0x1
EPOLL_CTL_DEL = 0x2
EPOLL_CTL_MOD = 0x3
EFD_NONBLOCK = 0x800
)
type EpollEvent struct {

2
src/runtime/internal/syscall/defs_linux_amd64.go
View File

@ -10,6 +10,7 @@ const (
SYS_EPOLL_PWAIT = 281
SYS_EPOLL_CREATE1 = 291
SYS_EPOLL_PWAIT2 = 441
SYS_EVENTFD2 = 290
EPOLLIN = 0x1
EPOLLOUT = 0x4
@ -21,6 +22,7 @@ const (
EPOLL_CTL_ADD = 0x1
EPOLL_CTL_DEL = 0x2
EPOLL_CTL_MOD = 0x3
EFD_NONBLOCK = 0x800
)
type EpollEvent struct {

2
src/runtime/internal/syscall/defs_linux_arm.go
View File

@ -10,6 +10,7 @@ const (
SYS_EPOLL_PWAIT = 346
SYS_EPOLL_CREATE1 = 357
SYS_EPOLL_PWAIT2 = 441
SYS_EVENTFD2 = 356
EPOLLIN = 0x1
EPOLLOUT = 0x4
@ -21,6 +22,7 @@ const (
EPOLL_CTL_ADD = 0x1
EPOLL_CTL_DEL = 0x2
EPOLL_CTL_MOD = 0x3
EFD_NONBLOCK = 0x800
)
type EpollEvent struct {

2
src/runtime/internal/syscall/defs_linux_arm64.go
View File

@ -10,6 +10,7 @@ const (
SYS_EPOLL_PWAIT = 22
SYS_FCNTL = 25
SYS_EPOLL_PWAIT2 = 441
SYS_EVENTFD2 = 19
EPOLLIN = 0x1
EPOLLOUT = 0x4
@ -21,6 +22,7 @@ const (
EPOLL_CTL_ADD = 0x1
EPOLL_CTL_DEL = 0x2
EPOLL_CTL_MOD = 0x3
EFD_NONBLOCK = 0x800
)
type EpollEvent struct {

2
src/runtime/internal/syscall/defs_linux_loong64.go
View File

@ -10,6 +10,7 @@ const (
SYS_EPOLL_PWAIT = 22
SYS_FCNTL = 25
SYS_EPOLL_PWAIT2 = 441
SYS_EVENTFD2 = 19
EPOLLIN = 0x1
EPOLLOUT = 0x4
@ -21,6 +22,7 @@ const (
EPOLL_CTL_ADD = 0x1
EPOLL_CTL_DEL = 0x2
EPOLL_CTL_MOD = 0x3
EFD_NONBLOCK = 0x800
)
type EpollEvent struct {

2
src/runtime/internal/syscall/defs_linux_mips64x.go
View File

@ -12,6 +12,7 @@ const (
SYS_EPOLL_PWAIT = 5272
SYS_EPOLL_CREATE1 = 5285
SYS_EPOLL_PWAIT2 = 5441
SYS_EVENTFD2 = 5284
EPOLLIN = 0x1
EPOLLOUT = 0x4
@ -23,6 +24,7 @@ const (
EPOLL_CTL_ADD = 0x1
EPOLL_CTL_DEL = 0x2
EPOLL_CTL_MOD = 0x3
EFD_NONBLOCK = 0x80
)
type EpollEvent struct {

2
src/runtime/internal/syscall/defs_linux_mipsx.go
View File

@ -12,6 +12,7 @@ const (
SYS_EPOLL_PWAIT = 4313
SYS_EPOLL_CREATE1 = 4326
SYS_EPOLL_PWAIT2 = 4441
SYS_EVENTFD2 = 4325
EPOLLIN = 0x1
EPOLLOUT = 0x4
@ -23,6 +24,7 @@ const (
EPOLL_CTL_ADD = 0x1
EPOLL_CTL_DEL = 0x2
EPOLL_CTL_MOD = 0x3
EFD_NONBLOCK = 0x80
)
type EpollEvent struct {

2
src/runtime/internal/syscall/defs_linux_ppc64x.go
View File

@ -12,6 +12,7 @@ const (
SYS_EPOLL_PWAIT = 303
SYS_EPOLL_CREATE1 = 315
SYS_EPOLL_PWAIT2 = 441
SYS_EVENTFD2 = 314
EPOLLIN = 0x1
EPOLLOUT = 0x4
@ -23,6 +24,7 @@ const (
EPOLL_CTL_ADD = 0x1
EPOLL_CTL_DEL = 0x2
EPOLL_CTL_MOD = 0x3
EFD_NONBLOCK = 0x800
)
type EpollEvent struct {

2
src/runtime/internal/syscall/defs_linux_riscv64.go
View File

@ -10,6 +10,7 @@ const (
SYS_EPOLL_PWAIT = 22
SYS_FCNTL = 25
SYS_EPOLL_PWAIT2 = 441
SYS_EVENTFD2 = 19
EPOLLIN = 0x1
EPOLLOUT = 0x4
@ -21,6 +22,7 @@ const (
EPOLL_CTL_ADD = 0x1
EPOLL_CTL_DEL = 0x2
EPOLL_CTL_MOD = 0x3
EFD_NONBLOCK = 0x800
)
type EpollEvent struct {

2
src/runtime/internal/syscall/defs_linux_s390x.go
View File

@ -10,6 +10,7 @@ const (
SYS_EPOLL_PWAIT = 312
SYS_EPOLL_CREATE1 = 327
SYS_EPOLL_PWAIT2 = 441
SYS_EVENTFD2 = 323
EPOLLIN = 0x1
EPOLLOUT = 0x4
@ -21,6 +22,7 @@ const (
EPOLL_CTL_ADD = 0x1
EPOLL_CTL_DEL = 0x2
EPOLL_CTL_MOD = 0x3
EFD_NONBLOCK = 0x800
)
type EpollEvent struct {

5
src/runtime/internal/syscall/syscall_linux.go
View File

@ -60,3 +60,8 @@ func EpollCtl(epfd, op, fd int32, event *EpollEvent) (errno uintptr) {
_, _, e := Syscall6(SYS_EPOLL_CTL, uintptr(epfd), uintptr(op), uintptr(fd), uintptr(unsafe.Pointer(event)), 0, 0)
return e
}
func Eventfd(initval, flags int32) (fd int32, errno uintptr) {
r1, _, e := Syscall6(SYS_EVENTFD2, uintptr(initval), uintptr(flags), 0, 0, 0, 0)
return int32(r1), e
}

48
src/runtime/netpoll_epoll.go
View File

@ -13,11 +13,9 @@ import (
)
var (
epfd int32 = -1 // epoll descriptor
netpollBreakRd, netpollBreakWr uintptr // for netpollBreak
netpollWakeSig atomic.Uint32 // used to avoid duplicate calls of netpollBreak
epfd int32 = -1 // epoll descriptor
netpollEventFd uintptr // eventfd for netpollBreak
netpollWakeSig atomic.Uint32 // used to avoid duplicate calls of netpollBreak
)
func netpollinit() {
@ -27,26 +25,25 @@ func netpollinit() {
println("runtime: epollcreate failed with", errno)
throw("runtime: netpollinit failed")
}
r, w, errpipe := nonblockingPipe()
if errpipe != 0 {
println("runtime: pipe failed with", -errpipe)
throw("runtime: pipe failed")
efd, errno := syscall.Eventfd(0, syscall.EFD_CLOEXEC|syscall.EFD_NONBLOCK)
if errno != 0 {
println("runtime: eventfd failed with", -errno)
throw("runtime: eventfd failed")
}
ev := syscall.EpollEvent{
Events: syscall.EPOLLIN,
}
*(**uintptr)(unsafe.Pointer(&ev.Data)) = &netpollBreakRd
errno = syscall.EpollCtl(epfd, syscall.EPOLL_CTL_ADD, r, &ev)
*(**uintptr)(unsafe.Pointer(&ev.Data)) = &netpollEventFd
errno = syscall.EpollCtl(epfd, syscall.EPOLL_CTL_ADD, efd, &ev)
if errno != 0 {
println("runtime: epollctl failed with", errno)
throw("runtime: epollctl failed")
}
netpollBreakRd = uintptr(r)
netpollBreakWr = uintptr(w)
netpollEventFd = uintptr(efd)
}
func netpollIsPollDescriptor(fd uintptr) bool {
return fd == uintptr(epfd) || fd == netpollBreakRd || fd == netpollBreakWr
return fd == uintptr(epfd) || fd == netpollEventFd
}
func netpollopen(fd uintptr, pd *pollDesc) uintptr {
@ -73,10 +70,11 @@ func netpollBreak() {
return
}
var one uint64 = 1
oneSize := int32(unsafe.Sizeof(one))
for {
var b byte
n := write(netpollBreakWr, unsafe.Pointer(&b), 1)
if n == 1 {
n := write(netpollEventFd, noescape(unsafe.Pointer(&one)), oneSize)
if n == oneSize {
break
}
if n == -_EINTR {
@ -136,17 +134,19 @@ retry:
continue
}
if *(**uintptr)(unsafe.Pointer(&ev.Data)) == &netpollBreakRd {
if *(**uintptr)(unsafe.Pointer(&ev.Data)) == &netpollEventFd {
if ev.Events != syscall.EPOLLIN {
println("runtime: netpoll: break fd ready for", ev.Events)
throw("runtime: netpoll: break fd ready for something unexpected")
println("runtime: netpoll: eventfd ready for", ev.Events)
throw("runtime: netpoll: eventfd ready for something unexpected")
}
if delay != 0 {
// netpollBreak could be picked up by a
// nonblocking poll. Only read the byte
// if blocking.
var tmp [16]byte
read(int32(netpollBreakRd), noescape(unsafe.Pointer(&tmp[0])), int32(len(tmp)))
// nonblocking poll. Only read the 8-byte
// integer if blocking.
// Since EFD_SEMAPHORE was not specified,
// the eventfd counter will be reset to 0.
var one uint64
read(int32(netpollEventFd), noescape(unsafe.Pointer(&one)), int32(unsafe.Sizeof(one)))
netpollWakeSig.Store(0)
}
continue