Use GCD instead of Detached Thread in Async Resolver when on MacOS/iOS
The advantage is that GCD maintains the internal thread pool and
spawns threads when needed. I would expect the behavior to be
almost identical to creating a thread using PlatformThread.
Bug: webrtc:13237
Change-Id: Ie4406b5d128c244f66a73830d5a27f2d8fd88549
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/234300
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
Commit-Queue: Byoungchan Lee <daniel.l@hpcnt.com>
Cr-Commit-Position: refs/heads/main@{#35165}
diff --git a/rtc_base/BUILD.gn b/rtc_base/BUILD.gn
index 8fb8193..d9fe93e 100644
--- a/rtc_base/BUILD.gn
+++ b/rtc_base/BUILD.gn
@@ -542,7 +542,10 @@
if (is_mac || is_ios) {
rtc_library("rtc_task_queue_gcd") {
- visibility = [ "../api/task_queue:default_task_queue_factory" ]
+ visibility = [
+ ":threading",
+ "../api/task_queue:default_task_queue_factory",
+ ]
sources = [
"task_queue_gcd.cc",
"task_queue_gcd.h",
@@ -832,7 +835,10 @@
deps += [ ":win32" ]
}
if (is_mac || is_ios) {
- deps += [ "system:cocoa_threading" ]
+ deps += [
+ ":rtc_task_queue_gcd",
+ "system:cocoa_threading",
+ ]
}
}
diff --git a/rtc_base/async_resolver.cc b/rtc_base/async_resolver.cc
index 75efce5..231e4fa 100644
--- a/rtc_base/async_resolver.cc
+++ b/rtc_base/async_resolver.cc
@@ -40,6 +40,10 @@
#include "rtc_base/task_utils/to_queued_task.h"
#include "rtc_base/third_party/sigslot/sigslot.h" // for signal_with_thread...
+#if defined(WEBRTC_MAC) || defined(WEBRTC_IOS)
+#include "rtc_base/task_queue_gcd.h"
+#endif
+
namespace rtc {
int ResolveHostname(const std::string& hostname,
@@ -123,7 +127,7 @@
RTC_DCHECK_RUN_ON(&sequence_checker_);
RTC_DCHECK(!destroy_called_);
addr_ = addr;
- PlatformThread::SpawnDetached(
+ auto thread_function =
[this, addr, caller_task_queue = webrtc::TaskQueueBase::Current(),
state = state_] {
std::vector<IPAddress> addresses;
@@ -146,8 +150,13 @@
}
}));
}
- },
- "AsyncResolver");
+ };
+#if defined(WEBRTC_MAC) || defined(WEBRTC_IOS)
+ webrtc::PostTaskToGlobalQueue(
+ webrtc::ToQueuedTask(std::move(thread_function)));
+#else
+ PlatformThread::SpawnDetached(std::move(thread_function), "AsyncResolver");
+#endif
}
bool AsyncResolver::GetResolvedAddress(int family, SocketAddress* addr) const {
diff --git a/rtc_base/task_queue_gcd.cc b/rtc_base/task_queue_gcd.cc
index 2276f63..aefc207 100644
--- a/rtc_base/task_queue_gcd.cc
+++ b/rtc_base/task_queue_gcd.cc
@@ -145,10 +145,24 @@
}
};
+// static
+void GlobalGcdRunTask(void* context) {
+ std::unique_ptr<QueuedTask> task(static_cast<QueuedTask*>(context));
+ task->Run();
+}
+
} // namespace
std::unique_ptr<TaskQueueFactory> CreateTaskQueueGcdFactory() {
return std::make_unique<TaskQueueGcdFactory>();
}
+void PostTaskToGlobalQueue(std::unique_ptr<QueuedTask> task,
+ TaskQueueFactory::Priority priority) {
+ dispatch_queue_global_t global_queue =
+ dispatch_get_global_queue(TaskQueuePriorityToGCD(priority), 0);
+ QueuedTask* context = task.release();
+ dispatch_async_f(global_queue, context, &GlobalGcdRunTask);
+}
+
} // namespace webrtc
diff --git a/rtc_base/task_queue_gcd.h b/rtc_base/task_queue_gcd.h
index dc6039e..898c2a3 100644
--- a/rtc_base/task_queue_gcd.h
+++ b/rtc_base/task_queue_gcd.h
@@ -19,6 +19,11 @@
std::unique_ptr<TaskQueueFactory> CreateTaskQueueGcdFactory();
+// Post a task into the system-defined global concurrent queue.
+void PostTaskToGlobalQueue(
+ std::unique_ptr<QueuedTask> task,
+ TaskQueueFactory::Priority priority = TaskQueueFactory::Priority::NORMAL);
+
} // namespace webrtc
#endif // RTC_BASE_TASK_QUEUE_GCD_H_
