Video capture PipeWire: simplify thread and lock annotations
Use only one RaceChecker as intended with the original change. This gets
rid of specific RaceChecker for PipeWire members. Make PipeWireSession
guarded by API checker instead, since this member is accessed only in
[Start/Stop]Capture and move the race checker within PipeWire thread
loop lock. Also remove race check from OnStreamStateChanged where we
only modify one property guarded by API mutex.
Partially reverts a9d497b52dc21497fdfd0e8c03ab2f8559e02d15 reviewed
on https://webrtc-review.googlesource.com/c/src/+/326781.
Bug: webrtc:15181
Change-Id: I46449fce86611124688a65d5337771c75853f2ca
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/338021
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Commit-Queue: Jan Grulich <grulja@gmail.com>
Cr-Commit-Position: refs/heads/main@{#41713}
diff --git a/modules/video_capture/linux/video_capture_pipewire.cc b/modules/video_capture/linux/video_capture_pipewire.cc
index fb813e3..8af4836 100644
--- a/modules/video_capture/linux/video_capture_pipewire.cc
+++ b/modules/video_capture/linux/video_capture_pipewire.cc
@@ -121,7 +121,6 @@
int32_t VideoCaptureModulePipeWire::StartCapture(
const VideoCaptureCapability& capability) {
- RTC_CHECK_RUNS_SERIALIZED(&capture_checker_);
RTC_DCHECK_RUN_ON(&api_checker_);
if (initialized_) {
@@ -134,10 +133,17 @@
uint8_t buffer[1024] = {};
+ // We don't want members above to be guarded by capture_checker_ as
+ // it's meant to be for members that are accessed on the API thread
+ // only when we are not capturing. The code above can be called many
+ // times while sharing instance of VideoCapturePipeWire between
+ // websites and therefore it would not follow the requirements of this
+ // checker.
+ RTC_CHECK_RUNS_SERIALIZED(&capture_checker_);
+ PipeWireThreadLoopLock thread_loop_lock(session_->pw_main_loop_);
+
RTC_LOG(LS_VERBOSE) << "Creating new PipeWire stream for node " << node_id_;
- PipeWireThreadLoopLock thread_loop_lock(session_->pw_main_loop_);
- RTC_CHECK_RUNS_SERIALIZED(&pipewire_checker_);
pw_properties* reuse_props =
pw_properties_new_string("pipewire.client.reuse=1");
stream_ = pw_stream_new(session_->pw_core_, "camera-stream", reuse_props);
@@ -188,11 +194,13 @@
}
int32_t VideoCaptureModulePipeWire::StopCapture() {
- RTC_CHECK_RUNS_SERIALIZED(&capture_checker_);
RTC_DCHECK_RUN_ON(&api_checker_);
PipeWireThreadLoopLock thread_loop_lock(session_->pw_main_loop_);
- RTC_CHECK_RUNS_SERIALIZED(&pipewire_checker_);
+ // PipeWireSession is guarded by API checker so just make sure we do
+ // race detection when the PipeWire loop is locked/stopped to not run
+ // any callback at this point.
+ RTC_CHECK_RUNS_SERIALIZED(&capture_checker_);
if (stream_) {
pw_stream_destroy(stream_);
stream_ = nullptr;
@@ -225,14 +233,14 @@
VideoCaptureModulePipeWire* that =
static_cast<VideoCaptureModulePipeWire*>(data);
RTC_DCHECK(that);
- RTC_CHECK_RUNS_SERIALIZED(&that->pipewire_checker_);
+ RTC_CHECK_RUNS_SERIALIZED(&that->capture_checker_);
if (format && id == SPA_PARAM_Format)
that->OnFormatChanged(format);
}
void VideoCaptureModulePipeWire::OnFormatChanged(const struct spa_pod* format) {
- RTC_CHECK_RUNS_SERIALIZED(&pipewire_checker_);
+ RTC_CHECK_RUNS_SERIALIZED(&capture_checker_);
uint32_t media_type, media_subtype;
@@ -331,7 +339,6 @@
VideoCaptureModulePipeWire* that =
static_cast<VideoCaptureModulePipeWire*>(data);
RTC_DCHECK(that);
- RTC_CHECK_RUNS_SERIALIZED(&that->capture_checker_);
MutexLock lock(&that->api_lock_);
switch (state) {
@@ -374,7 +381,7 @@
}
void VideoCaptureModulePipeWire::ProcessBuffers() {
- RTC_CHECK_RUNS_SERIALIZED(&pipewire_checker_);
+ RTC_CHECK_RUNS_SERIALIZED(&capture_checker_);
while (pw_buffer* buffer = pw_stream_dequeue_buffer(stream_)) {
struct spa_meta_header* h;
diff --git a/modules/video_capture/linux/video_capture_pipewire.h b/modules/video_capture/linux/video_capture_pipewire.h
index 5d6794e..eeb3b94 100644
--- a/modules/video_capture/linux/video_capture_pipewire.h
+++ b/modules/video_capture/linux/video_capture_pipewire.h
@@ -43,18 +43,16 @@
void OnFormatChanged(const struct spa_pod* format);
void ProcessBuffers();
- rtc::RaceChecker pipewire_checker_;
-
const rtc::scoped_refptr<PipeWireSession> session_
- RTC_GUARDED_BY(capture_checker_);
+ RTC_GUARDED_BY(api_checker_);
+ bool initialized_ RTC_GUARDED_BY(api_checker_);
+ bool started_ RTC_GUARDED_BY(api_lock_);
int node_id_ RTC_GUARDED_BY(capture_checker_);
VideoCaptureCapability configured_capability_
- RTC_GUARDED_BY(pipewire_checker_);
- bool initialized_ RTC_GUARDED_BY(capture_checker_);
- bool started_ RTC_GUARDED_BY(api_lock_);
+ RTC_GUARDED_BY(capture_checker_);
- struct pw_stream* stream_ RTC_GUARDED_BY(pipewire_checker_) = nullptr;
- struct spa_hook stream_listener_ RTC_GUARDED_BY(pipewire_checker_);
+ struct pw_stream* stream_ RTC_GUARDED_BY(capture_checker_) = nullptr;
+ struct spa_hook stream_listener_ RTC_GUARDED_BY(capture_checker_);
};
} // namespace videocapturemodule
} // namespace webrtc
