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cleanup getEventHandle

master
kprotty 2019-11-07 19:37:53 -06:00
parent 43900011f7
commit e2189b6e5d
1 changed files with 15 additions and 13 deletions
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28
lib/std/parker.zig
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@ -78,12 +78,12 @@ const WindowsParker = struct {
pub fn unpark(self: *WindowsParker, ptr: *const u32) void {
const key = @ptrCast(*const c_void, ptr);
const handle_ptr = getEventHandlePtr() orelse return;
const handle = getEventHandle() orelse return;
var waiting = @atomicLoad(u32, &self.waiters, .Monotonic);
while (waiting != 0) {
waiting = @cmpxchgWeak(u32, &self.waiters, waiting, waiting - 1, .Acquire, .Monotonic) orelse {
const rc = windows.ntdll.NtReleaseKeyedEvent(handle_ptr.*, key, windows.FALSE, null);
const rc = windows.ntdll.NtReleaseKeyedEvent(handle, key, windows.FALSE, null);
assert(rc == 0);
return;
};
@ -92,12 +92,13 @@ const WindowsParker = struct {
pub fn park(self: *WindowsParker, ptr: *const u32, expected: u32) void {
var spin = SpinLock.Backoff.init();
const ev_handle = getEventHandle();
const key = @ptrCast(*const c_void, ptr);
while (@atomicLoad(u32, ptr, .Acquire) == expected) {
if (getEventHandlePtr()) |handle_ptr| {
while (@atomicLoad(u32, ptr, .Monotonic) == expected) {
if (ev_handle) |handle| {
_ = @atomicRmw(u32, &self.waiters, .Add, 1, .Release);
const rc = windows.ntdll.NtWaitForKeyedEvent(handle_ptr.*, key, windows.FALSE, null);
const rc = windows.ntdll.NtWaitForKeyedEvent(handle, key, windows.FALSE, null);
assert(rc == 0);
} else {
spin.yield();
@ -107,14 +108,15 @@ const WindowsParker = struct {
var event_handle = std.lazyInit(windows.HANDLE);
fn getEventHandlePtr() ?*const windows.HANDLE {
return event_handle.get() orelse {
const access_mask = windows.GENERIC_READ | windows.GENERIC_WRITE;
if (windows.ntdll.NtCreateKeyedEvent(&event_handle.data, access_mask, null, 0) != 0)
return null;
event_handle.resolve();
return &event_handle.data;
};
fn getEventHandle() ?windows.HANDLE {
if (event_handle.get()) |handle_ptr|
return handle_ptr.*;
defer event_handle.resolve();
const access_mask = windows.GENERIC_READ | windows.GENERIC_WRITE;
if (windows.ntdll.NtCreateKeyedEvent(&event_handle.data, access_mask, null, 0) != 0)
return null;
return event_handle.data;
}
};