Add ability to change context priority of RT GL context

Test: Use method, observe GPU preemption behavior
Bug: 75985430
Change-Id: Idc08d37f8c95f52c5aab7edf09c0cbff72b8482d

3 files changed, 16 insertions, 2 deletions

diff --git a/libs/hwui/Properties.cpp b/libs/hwui/Properties.cpp
index 1602b4b39c91..0a6c45beedf9 100644
--- a/libs/hwui/Properties.cpp
+++ b/libs/hwui/Properties.cpp
@@ -65,6 +65,8 @@ bool Properties::runningInEmulator = false;
 bool Properties::debuggingEnabled = false;
 bool Properties::isolatedProcess = false;
 
+int Properties::contextPriority = 0;
+
 static int property_get_int(const char* key, int defaultValue) {
     char buf[PROPERTY_VALUE_MAX] = {
             '\0',
diff --git a/libs/hwui/Properties.h b/libs/hwui/Properties.h
index 81a36574a097..764c50259540 100644
--- a/libs/hwui/Properties.h
+++ b/libs/hwui/Properties.h
@@ -271,6 +271,8 @@ public:
     ANDROID_API static bool debuggingEnabled;
     ANDROID_API static bool isolatedProcess;
 
+    ANDROID_API static int contextPriority;
+
 private:
     static ProfileType sProfileType;
     static bool sDisableProfileBars;
diff --git a/libs/hwui/renderthread/EglManager.cpp b/libs/hwui/renderthread/EglManager.cpp
index 5b87e1013baf..6e239e357cf6 100644
--- a/libs/hwui/renderthread/EglManager.cpp
+++ b/libs/hwui/renderthread/EglManager.cpp
@@ -82,6 +82,7 @@ static struct {
     bool pixelFormatFloat = false;
     bool glColorSpace = false;
     bool scRGB = false;
+    bool contextPriority = false;
 } EglExtensions;
 
 EglManager::EglManager(RenderThread& thread)
@@ -168,6 +169,7 @@ void EglManager::initExtensions() {
 #else
     EglExtensions.scRGB = extensions.has("EGL_EXT_gl_colorspace_scrgb");
 #endif
+    EglExtensions.contextPriority = extensions.has("EGL_IMG_context_priority");
 }
 
 bool EglManager::hasEglContext() {
@@ -247,10 +249,18 @@ void EglManager::loadConfigs() {
 }
 
 void EglManager::createContext() {
-    EGLint attribs[] = {EGL_CONTEXT_CLIENT_VERSION, GLES_VERSION, EGL_NONE};
+    std::vector<EGLint> contextAttributes;
+    contextAttributes.reserve(5);
+    contextAttributes.push_back(EGL_CONTEXT_CLIENT_VERSION);
+    contextAttributes.push_back(GLES_VERSION);
+    if (Properties::contextPriority != 0 && EglExtensions.contextPriority) {
+        contextAttributes.push_back(EGL_CONTEXT_PRIORITY_LEVEL_IMG);
+        contextAttributes.push_back(Properties::contextPriority);
+    }
+    contextAttributes.push_back(EGL_NONE);
     mEglContext = eglCreateContext(
             mEglDisplay, EglExtensions.noConfigContext ? ((EGLConfig) nullptr) : mEglConfig,
-            EGL_NO_CONTEXT, attribs);
+            EGL_NO_CONTEXT, contextAttributes.data());
     LOG_ALWAYS_FATAL_IF(mEglContext == EGL_NO_CONTEXT, "Failed to create context, error = %s",
                         eglErrorString());
 }