systrace: monitor GPU completion fence and HWC release fence

Bug: 127781085
Test: build, flash, boot and take systrace with gfx category
Change-Id: I7a1e28a7498bcdfd1b4286fffbe6d58bddddf049

diff --git a/libs/gui/Surface.cpp b/libs/gui/Surface.cpp
index 3affa23..af6373d 100644 (file)
--- a/libs/gui/Surface.cpp
+++ b/libs/gui/Surface.cpp
@@ -20,6 +20,11 @@
 
 #include <gui/Surface.h>
 
+#include <condition_variable>
+#include <deque>
+#include <mutex>
+#include <thread>
+
 #include <inttypes.h>
 
 #include <android/native_window.h>
@@ -450,6 +455,74 @@ int Surface::setSwapInterval(int interval) {
     return NO_ERROR;
 }
 
+class FenceMonitor {
+public:
+    explicit FenceMonitor(const char* name) : mName(name), mFencesQueued(0), mFencesSignaled(0) {
+        std::thread thread(&FenceMonitor::loop, this);
+        pthread_setname_np(thread.native_handle(), mName);
+        thread.detach();
+    }
+
+    void queueFence(const sp<Fence>& fence) {
+        char message[64];
+
+        std::lock_guard<std::mutex> lock(mMutex);
+        snprintf(message, sizeof(message), "Trace fence %u", mFencesQueued);
+        ATRACE_NAME(message);
+
+        mQueue.push_back(fence);
+        mCondition.notify_one();
+        mFencesQueued++;
+        ATRACE_INT(mName, int32_t(mQueue.size()));
+    }
+
+private:
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wmissing-noreturn"
+    void loop() {
+        while (true) {
+            threadLoop();
+        }
+    }
+#pragma clang diagnostic pop
+
+    void threadLoop() {
+        sp<Fence> fence;
+        uint32_t fenceNum;
+        {
+            std::unique_lock<std::mutex> lock(mMutex);
+            while (mQueue.empty()) {
+                mCondition.wait(lock);
+            }
+            fence = mQueue[0];
+            fenceNum = mFencesSignaled;
+        }
+        {
+            char message[64];
+            snprintf(message, sizeof(message), "waiting for %s %u", mName, fenceNum);
+            ATRACE_NAME(message);
+
+            status_t result = fence->waitForever(message);
+            if (result != OK) {
+                ALOGE("Error waiting for fence: %d", result);
+            }
+        }
+        {
+            std::lock_guard<std::mutex> lock(mMutex);
+            mQueue.pop_front();
+            mFencesSignaled++;
+            ATRACE_INT(mName, int32_t(mQueue.size()));
+        }
+    }
+
+    const char* mName;
+    uint32_t mFencesQueued;
+    uint32_t mFencesSignaled;
+    std::deque<sp<Fence>> mQueue;
+    std::condition_variable mCondition;
+    std::mutex mMutex;
+};
+
 int Surface::dequeueBuffer(android_native_buffer_t** buffer, int* fenceFd) {
     ATRACE_CALL();
     ALOGV("Surface::dequeueBuffer");
@@ -519,6 +592,11 @@ int Surface::dequeueBuffer(android_native_buffer_t** buffer, int* fenceFd) {
     // this should never happen
     ALOGE_IF(fence == nullptr, "Surface::dequeueBuffer: received null Fence! buf=%d", buf);
 
+    if (CC_UNLIKELY(atrace_is_tag_enabled(ATRACE_TAG_GRAPHICS))) {
+        static FenceMonitor hwcReleaseThread("HWC release");
+        hwcReleaseThread.queueFence(fence);
+    }
+
     if (result & IGraphicBufferProducer::RELEASE_ALL_BUFFERS) {
         freeAllBuffers();
     }
@@ -761,6 +839,11 @@ int Surface::queueBuffer(android_native_buffer_t* buffer, int fenceFd) {
 
     mQueueBufferCondition.broadcast();
 
+    if (CC_UNLIKELY(atrace_is_tag_enabled(ATRACE_TAG_GRAPHICS))) {
+        static FenceMonitor gpuCompletionThread("GPU completion");
+        gpuCompletionThread.queueFence(fence);
+    }
+
     return err;
 }