std.event.Loop: fix not waking up after file system I/O

for single threaded event loops
This commit is contained in:
Andrew Kelley 2019-08-16 23:19:13 -04:00
parent 3dce41b61a
commit e24cc2e77b
No known key found for this signature in database
GPG Key ID: 7C5F548F728501A9
2 changed files with 11 additions and 9 deletions

View File

@ -69,6 +69,7 @@ pub extern "c" fn raise(sig: c_int) c_int;
pub extern "c" fn read(fd: fd_t, buf: [*]u8, nbyte: usize) isize;
pub extern "c" fn pread(fd: fd_t, buf: [*]u8, nbyte: usize, offset: u64) isize;
pub extern "c" fn preadv(fd: c_int, iov: [*]const iovec, iovcnt: c_uint, offset: usize) isize;
pub extern "c" fn writev(fd: c_int, iov: [*]const iovec_const, iovcnt: c_uint) isize;
pub extern "c" fn pwritev(fd: c_int, iov: [*]const iovec_const, iovcnt: c_uint, offset: usize) isize;
pub extern "c" fn stat(noalias path: [*]const u8, noalias buf: *Stat) c_int;
pub extern "c" fn write(fd: fd_t, buf: [*]const u8, nbyte: usize) isize;

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@ -149,13 +149,14 @@ pub const Loop = struct {
.overlapped = ResumeNode.overlapped_init,
},
};
const extra_thread_count = thread_count - 1;
// We need an extra one of these in case the fs thread wants to use onNextTick
self.eventfd_resume_nodes = try self.allocator.alloc(
std.atomic.Stack(ResumeNode.EventFd).Node,
extra_thread_count,
thread_count,
);
errdefer self.allocator.free(self.eventfd_resume_nodes);
const extra_thread_count = thread_count - 1;
self.extra_threads = try self.allocator.alloc(*Thread, extra_thread_count);
errdefer self.allocator.free(self.extra_threads);
@ -197,7 +198,7 @@ pub const Loop = struct {
eventfd_node.* = std.atomic.Stack(ResumeNode.EventFd).Node{
.data = ResumeNode.EventFd{
.base = ResumeNode{
.id = ResumeNode.Id.EventFd,
.id = .EventFd,
.handle = undefined,
.overlapped = ResumeNode.overlapped_init,
},
@ -454,12 +455,12 @@ pub const Loop = struct {
self.finishOneEvent();
}
pub async fn linuxWaitFd(self: *Loop, fd: i32, flags: u32) !void {
pub fn linuxWaitFd(self: *Loop, fd: i32, flags: u32) !void {
defer self.linuxRemoveFd(fd);
suspend {
var resume_node = ResumeNode.Basic{
.base = ResumeNode{
.id = ResumeNode.Id.Basic,
.id = .Basic,
.handle = @frame(),
.overlapped = ResumeNode.overlapped_init,
},
@ -793,8 +794,8 @@ pub const Loop = struct {
fn posixFsRun(self: *Loop) void {
while (true) {
if (builtin.os == builtin.Os.linux) {
_ = @atomicRmw(i32, &self.os_data.fs_queue_item, AtomicRmwOp.Xchg, 0, AtomicOrder.SeqCst);
if (builtin.os == .linux) {
_ = @atomicRmw(i32, &self.os_data.fs_queue_item, .Xchg, 0, .SeqCst);
}
while (self.os_data.fs_queue.get()) |node| {
switch (node.data.msg) {
@ -833,14 +834,14 @@ pub const Loop = struct {
self.finishOneEvent();
}
switch (builtin.os) {
builtin.Os.linux => {
.linux => {
const rc = os.linux.futex_wait(&self.os_data.fs_queue_item, os.linux.FUTEX_WAIT, 0, null);
switch (os.linux.getErrno(rc)) {
0, os.EINTR, os.EAGAIN => continue,
else => unreachable,
}
},
builtin.Os.macosx, builtin.Os.freebsd, builtin.Os.netbsd => {
.macosx, .freebsd, .netbsd => {
const fs_kevs = (*const [1]os.Kevent)(&self.os_data.fs_kevent_wait);
var out_kevs: [1]os.Kevent = undefined;
_ = os.kevent(self.os_data.fs_kqfd, fs_kevs, out_kevs[0..], null) catch unreachable;