[libcamera-devel] [PATCH v1 4/5] cam: event_loop: Add deferred calls support
Laurent Pinchart
laurent.pinchart at ideasonboard.com
Fri Nov 13 07:38:14 CET 2020
Add a deferred cals queue to the EventLoop class to support queuing
calls from a different thread and processing them in the event loop's
thread.
Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
---
src/cam/event_loop.cpp | 29 ++++++++++++++++++++++++++++-
src/cam/event_loop.h | 9 +++++++++
2 files changed, 37 insertions(+), 1 deletion(-)
diff --git a/src/cam/event_loop.cpp b/src/cam/event_loop.cpp
index 13f2583da0a1..94c5d1d36245 100644
--- a/src/cam/event_loop.cpp
+++ b/src/cam/event_loop.cpp
@@ -40,8 +40,10 @@ int EventLoop::exec()
exitCode_ = -1;
exit_.store(false, std::memory_order_release);
- while (!exit_.load(std::memory_order_acquire))
+ while (!exit_.load(std::memory_order_acquire)) {
+ dispatchCalls();
event_base_loop(event_, EVLOOP_NO_EXIT_ON_EMPTY);
+ }
return exitCode_;
}
@@ -57,3 +59,28 @@ void EventLoop::interrupt()
{
event_base_loopbreak(event_);
}
+
+void EventLoop::callLater(const std::function<void()> &func)
+{
+ {
+ std::unique_lock<std::mutex> locker(lock_);
+ calls_.push_back(func);
+ }
+
+ interrupt();
+}
+
+void EventLoop::dispatchCalls()
+{
+ std::unique_lock<std::mutex> locker(lock_);
+
+ for (auto iter = calls_.begin(); iter != calls_.end(); ) {
+ std::function<void()> call = std::move(*iter);
+
+ iter = calls_.erase(iter);
+
+ locker.unlock();
+ call();
+ locker.lock();
+ }
+}
diff --git a/src/cam/event_loop.h b/src/cam/event_loop.h
index b1c6bd103080..408073c50594 100644
--- a/src/cam/event_loop.h
+++ b/src/cam/event_loop.h
@@ -8,6 +8,9 @@
#define __CAM_EVENT_LOOP_H__
#include <atomic>
+#include <functional>
+#include <list>
+#include <mutex>
struct event_base;
@@ -22,6 +25,8 @@ public:
int exec();
void exit(int code = 0);
+ void callLater(const std::function<void()> &func);
+
private:
static EventLoop *instance_;
@@ -29,7 +34,11 @@ private:
std::atomic<bool> exit_;
int exitCode_;
+ std::list<std::function<void()>> calls_;
+ std::mutex lock_;
+
void interrupt();
+ void dispatchCalls();
};
#endif /* __CAM_EVENT_LOOP_H__ */
--
Regards,
Laurent Pinchart
More information about the libcamera-devel
mailing list