authorgravatar for jacobly@ziglang.orgJacob Young <jacobly@ziglang.org> 2025-03-31 23:45:31-04:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2025-07-20 10:38:39-07:00
logf0919a4cea5bb8077b2f33896233f309ab351ca9
tree684c5895ca35356309d019e34dcd32472d359518
parentfa937d686d1ba86d6dba47f92353c139bd2145fc

EventLoop: revert incorrect optimization

1 files changed, 12 insertions(+), 4 deletions(-)

lib/std/Io/EventLoop.zig+12-4
...@@ -248,8 +248,16 @@ fn findReadyFiber(el: *EventLoop, thread: *Thread) ?*Fiber {...@@ -248,8 +248,16 @@ fn findReadyFiber(el: *EventLoop, thread: *Thread) ?*Fiber {
248 if (thread.steal_ready_search_index == active_threads) thread.steal_ready_search_index = 0;248 if (thread.steal_ready_search_index == active_threads) thread.steal_ready_search_index = 0;
249 const steal_ready_search_thread = &el.threads.allocated[0..active_threads][thread.steal_ready_search_index];249 const steal_ready_search_thread = &el.threads.allocated[0..active_threads][thread.steal_ready_search_index];
250 if (steal_ready_search_thread == thread) continue;250 if (steal_ready_search_thread == thread) continue;
251 const ready_fiber = @atomicRmw(?*Fiber, &steal_ready_search_thread.ready_queue, .And, Fiber.finished, .acquire) orelse continue;251 const ready_fiber = @atomicLoad(?*Fiber, &steal_ready_search_thread.ready_queue, .acquire) orelse continue;
252 if (ready_fiber == Fiber.finished) continue;252 if (ready_fiber == Fiber.finished) continue;
253 if (@cmpxchgWeak(
254 ?*Fiber,
255 &steal_ready_search_thread.ready_queue,
256 ready_fiber,
257 null,
258 .acquire,
259 .monotonic,
260 )) |_| continue;
253 @atomicStore(?*Fiber, &thread.ready_queue, ready_fiber.queue_next, .release);261 @atomicStore(?*Fiber, &thread.ready_queue, ready_fiber.queue_next, .release);
254 ready_fiber.queue_next = null;262 ready_fiber.queue_next = null;
255 return ready_fiber;263 return ready_fiber;
...@@ -297,7 +305,7 @@ fn schedule(el: *EventLoop, thread: *Thread, ready_queue: Fiber.Queue) void {...@@ -297,7 +305,7 @@ fn schedule(el: *EventLoop, thread: *Thread, ready_queue: Fiber.Queue) void {
297 &idle_search_thread.ready_queue,305 &idle_search_thread.ready_queue,
298 null,306 null,
299 ready_queue.head,307 ready_queue.head,
300 .acq_rel,308 .release,
301 .monotonic,309 .monotonic,
302 )) |_| continue;310 )) |_| continue;
303 getSqe(&thread.io_uring).* = .{311 getSqe(&thread.io_uring).* = .{
...@@ -1268,9 +1276,9 @@ fn conditionWait(userdata: ?*anyopaque, cond: *Io.Condition, mutex: *Io.Mutex) I...@@ -1268,9 +1276,9 @@ fn conditionWait(userdata: ?*anyopaque, cond: *Io.Condition, mutex: *Io.Mutex) I
1268 const fiber = thread.currentFiber();1276 const fiber = thread.currentFiber();
1269 const prev = @atomicRmw(?*Fiber, cond_state, .Xchg, fiber, .acquire);1277 const prev = @atomicRmw(?*Fiber, cond_state, .Xchg, fiber, .acquire);
1270 assert(prev == null); // More than one wait on same Condition is illegal.1278 assert(prev == null); // More than one wait on same Condition is illegal.
1271 mutex.unlock(io(el));1279 mutex.unlock(el.io());
1272 el.yield(null, .nothing);1280 el.yield(null, .nothing);
1273 try mutex.lock(io(el));1281 try mutex.lock(el.io());
1274}1282}
12751283
1276fn conditionWake(userdata: ?*anyopaque, cond: *Io.Condition) void {1284fn conditionWake(userdata: ?*anyopaque, cond: *Io.Condition) void {