From 4e6f963469d8f489586b2bf277af30e0fbfa1679 Mon Sep 17 00:00:00 2001 From: Andrew Pogrebnoy Date: Mon, 1 Aug 2022 17:58:17 +0300 Subject: runtime: move epoll syscalls to runtime/internal/syscall This change moves Linux epoll's syscalls implementation to the "runtime/internal/syscall" package. The intention in this CL was to minimise behavioural changes but make the code more generalised. This also will allow adding new syscalls (like epoll_pwait2) without the need to implement assembly stubs for each arch. It also drops epoll_create as not all architectures provide this call. epoll_create1 was added to the kernel in version 2.6.27 and Go requires Linux kernel version 2.6.32 or later since Go 1.18. So it is safe to always use epoll_create1. For #53824 For #51087 Change-Id: I9a6a26b7f2075a38e041de1bab4691da0ecb94fc Reviewed-on: https://go-review.googlesource.com/c/go/+/421994 Reviewed-by: Michael Pratt TryBot-Result: Gopher Robot Reviewed-by: Dmitri Shuralyov Run-TryBot: Michael Pratt Auto-Submit: Michael Pratt --- src/runtime/internal/syscall/syscall_linux.go | 29 ++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) (limited to 'src/runtime/internal/syscall/syscall_linux.go') diff --git a/src/runtime/internal/syscall/syscall_linux.go b/src/runtime/internal/syscall/syscall_linux.go index 7f268e8fba..a103d318c4 100644 --- a/src/runtime/internal/syscall/syscall_linux.go +++ b/src/runtime/internal/syscall/syscall_linux.go @@ -6,7 +6,7 @@ package syscall import ( - _ "unsafe" // for go:linkname + "unsafe" ) // TODO(https://go.dev/issue/51087): This package is incomplete and currently @@ -37,3 +37,30 @@ func Syscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr) func syscall_RawSyscall6(num, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, errno uintptr) { return Syscall6(num, a1, a2, a3, a4, a5, a6) } + +func EpollCreate1(flags int32) (fd int32, errno uintptr) { + r1, _, e := Syscall6(SYS_EPOLL_CREATE1, uintptr(flags), 0, 0, 0, 0, 0) + return int32(r1), e +} + +var _zero uintptr + +func EpollWait(epfd int32, events []EpollEvent, maxev, waitms int32) (n int32, errno uintptr) { + var ev unsafe.Pointer + if len(events) > 0 { + ev = unsafe.Pointer(&events[0]) + } else { + ev = unsafe.Pointer(&_zero) + } + r1, _, e := Syscall6(SYS_EPOLL_PWAIT, uintptr(epfd), uintptr(ev), uintptr(maxev), uintptr(waitms), 0, 0) + return int32(r1), e +} + +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 CloseOnExec(fd int32) { + Syscall6(SYS_FCNTL, uintptr(fd), F_SETFD, FD_CLOEXEC, 0, 0, 0) +} -- cgit v1.3