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Follow up: Availability of Set thread base priority when running escalated Tasks #85610

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Merged
merged 1 commit into from
Nov 20, 2025
Merged

Follow up: Availability of Set thread base priority when running escalated Tasks #85610

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6 changes: 3 additions & 3 deletions include/swift/Runtime/DispatchShims.h
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Original file line number Diff line number Diff line change
Expand Up @@ -51,9 +51,9 @@ swift_dispatch_thread_override_self(qos_class_t override_qos) {
static inline uint32_t
swift_dispatch_thread_override_self_with_base(qos_class_t override_qos, qos_class_t base_qos) {

if (__builtin_available(macOS 27.0, iOS 27.0, tvOS 27.0, watchOS 27.0, *)) {
if (__builtin_available(macOS 9998, iOS 9998, tvOS 9998, watchOS 9998, *)) {
return dispatch_thread_override_self_with_base(override_qos, base_qos);
} else if (__builtin_available(macOS 13.0, iOS 16.0, tvOS 16.0, watchOS 9.0, *)) {
} else if (__builtin_available(macOS 9998, iOS 9998, tvOS 9998, watchOS 9998, *)) {
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@dnadoba dnadoba Nov 20, 2025

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@ktoso why has this been changed? Shouldn't this stay with macOS 13 etc.?
Otherwise this doesn't make a lot of sense as this is already covered by the condition above.

// If we don't have the ability to set our base qos correctly, at least set the override
// We want to return 0 here because we have nothing to reset in this case
(void) dispatch_thread_override_self(override_qos);
Expand All @@ -64,7 +64,7 @@ swift_dispatch_thread_override_self_with_base(qos_class_t override_qos, qos_clas

static inline void
swift_dispatch_thread_reset_override_self(uint32_t opaque) {
if (__builtin_available(macOS 27.0, iOS 27.0, tvOS 27.0, watchOS 27.0, *)) {
if (__builtin_available(macOS 9998, iOS 9998, tvOS 9998, watchOS 9998, *)) {
dispatch_thread_reset_override_self(opaque);
}
}
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8 changes: 4 additions & 4 deletions test/Concurrency/async_task_priority.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -322,15 +322,15 @@ actor Test {
await task2.value // Escalate task2 which should be queued behind task1 on the actor
}

// This test will only work properly on 27.0+
if #available(macOS 27.0, iOS 27.0, tvOS 27.0, watchOS 27.0, *) {
// This test will only work properly if Dispatch supports lowering the base priority of a thread
if #available(macOS 9998, iOS 9998, tvOS 9998, watchOS 9998, *) {
tests.test("Task escalation doesn't impact qos_class_self") {
let task = Task(priority: .utility) {
let initialQos = DispatchQoS(
qosClass: DispatchQoS.QoSClass(rawValue: qos_class_self())!,
relativePriority: 0)
expectEqual(initialQos, DispatchQoS.utility)
let childTask = Task {
let innerTask = Task {
let qosBeforeEscalate = DispatchQoS(
qosClass: DispatchQoS.QoSClass(rawValue: qos_class_self())!,
relativePriority: 0)
Expand All @@ -353,7 +353,7 @@ actor Test {
expectEqual(qosAfterYield, DispatchQoS.utility)
}

await childTask.value
await innerTask.value
}

await task.value
Expand Down