Hibernate the EGL implementation when idle
If the EGL implementation supports the EGL_IMG_hibernate_process
extension, use it to hibernate (and hopefully release memory or other
resources) when the process isn't actively using EGL or OpenGL ES. The
idleness heuristic used in this change is:
(a) Wake up when entering any EGL API call, and remain awake for the
duration of the call.
(b) Do not hibernate when any window surface exists; this means the
application is very likely in the foreground.
(c) Do not hibernate while any context is made current to a thread.
The app may be using a client API without the EGL layer knowing,
so it is not safe to hibernate.
(d) Only check these conditions and attempt to hibernate after a
window surface is destroyed or a thread's context is detached. By
not attempting to hibernate at the end of every EGL call, we avoid
some transient wakeups/hibernate cycles when the app is mostly idle,
or is starting to become active but hasn't created its window
surface yet.
On a Galaxy Nexus, hibernating frees 1567 VM pages from the process.
Both hibernating and waking can take anywhere from 30ms to over 100ms
-- measurements have been very inconsistent.
Change-Id: Ib555f5d9d069aefccca06e8173a89625b5f32d7e
diff --git a/opengl/libs/EGL/eglApi.cpp b/opengl/libs/EGL/eglApi.cpp
index 969b50f..1bc4eb7 100644
--- a/opengl/libs/EGL/eglApi.cpp
+++ b/opengl/libs/EGL/eglApi.cpp
@@ -649,9 +649,11 @@
return NULL;
}
- // The EGL_ANDROID_blob_cache extension should not be exposed to
- // applications. It is used internally by the Android EGL layer.
- if (!strcmp(procname, "eglSetBlobCacheFuncsANDROID")) {
+ // These extensions should not be exposed to applications. They're used
+ // internally by the Android EGL layer.
+ if (!strcmp(procname, "eglSetBlobCacheFuncsANDROID") ||
+ !strcmp(procname, "eglHibernateProcessIMG") ||
+ !strcmp(procname, "eglAwakenProcessIMG")) {
return NULL;
}
diff --git a/opengl/libs/EGL/egl_display.cpp b/opengl/libs/EGL/egl_display.cpp
index 52e79f2..2e08f24 100644
--- a/opengl/libs/EGL/egl_display.cpp
+++ b/opengl/libs/EGL/egl_display.cpp
@@ -59,6 +59,7 @@
// extensions not exposed to applications but used by the ANDROID system
// "EGL_ANDROID_recordable " // mandatory
// "EGL_ANDROID_blob_cache " // strongly recommended
+// "EGL_IMG_hibernate_process " // optional
extern void initEglTraceLevel();
extern void initEglDebugLevel();
@@ -70,7 +71,7 @@
egl_display_t::egl_display_t() :
magic('_dpy'), finishOnSwap(false), traceGpuCompletion(false), refs(0),
- mWakeCount(0) {
+ mWakeCount(0), mHibernating(false), mAttemptHibernation(false) {
}
egl_display_t::~egl_display_t() {
@@ -349,12 +350,18 @@
disp.dpy, impl_draw, impl_read, impl_ctx);
if (result == EGL_TRUE) {
c->onMakeCurrent(draw, read);
+ if (!cur_c) {
+ mWakeCount++;
+ mAttemptHibernation = false;
+ }
}
} else {
result = cur_c->cnx->egl.eglMakeCurrent(
disp.dpy, impl_draw, impl_read, impl_ctx);
if (result == EGL_TRUE) {
cur_c->onLooseCurrent();
+ mWakeCount--;
+ mAttemptHibernation = true;
}
}
}
@@ -376,13 +383,45 @@
ALOGE_IF(mWakeCount < 0 || mWakeCount == INT32_MAX,
"Invalid WakeCount (%d) on enter\n", mWakeCount);
mWakeCount++;
+ if (CC_UNLIKELY(mHibernating)) {
+ ALOGV("Awakening\n");
+ egl_connection_t* const cnx = &gEGLImpl;
+ if (!cnx->egl.eglAwakenProcessIMG()) {
+ ALOGE("Failed to awaken EGL implementation\n");
+ return false;
+ }
+ mHibernating = false;
+ }
return true;
}
void egl_display_t::leave() {
Mutex::Autolock _l(lock);
ALOGE_IF(mWakeCount <= 0, "Invalid WakeCount (%d) on leave\n", mWakeCount);
+ if (--mWakeCount == 0 && CC_UNLIKELY(mAttemptHibernation)) {
+ egl_connection_t* const cnx = &gEGLImpl;
+ mAttemptHibernation = false;
+ if (cnx->egl.eglHibernateProcessIMG && cnx->egl.eglAwakenProcessIMG) {
+ ALOGV("Hibernating\n");
+ if (!cnx->egl.eglHibernateProcessIMG()) {
+ ALOGE("Failed to hibernate EGL implementation\n");
+ return;
+ }
+ mHibernating = true;
+ }
+ }
+}
+
+void egl_display_t::onWindowSurfaceCreated() {
+ Mutex::Autolock _l(lock);
+ mWakeCount++;
+ mAttemptHibernation = false;
+}
+
+void egl_display_t::onWindowSurfaceDestroyed() {
+ Mutex::Autolock _l(lock);
mWakeCount--;
+ mAttemptHibernation = true;
}
// ----------------------------------------------------------------------------
diff --git a/opengl/libs/EGL/egl_display.h b/opengl/libs/EGL/egl_display.h
index 8fd23eb..28607da 100644
--- a/opengl/libs/EGL/egl_display.h
+++ b/opengl/libs/EGL/egl_display.h
@@ -70,6 +70,16 @@
// add reference to this object. returns true if this is a valid object.
bool getObject(egl_object_t* object) const;
+ // These notifications allow the display to keep track of how many window
+ // surfaces exist, which it uses to decide whether to hibernate the
+ // underlying EGL implementation. They can be called by any thread without
+ // holding a lock, but must be called via egl_display_ptr to ensure
+ // proper hibernate/wakeup sequencing. If a surface destruction triggers
+ // hibernation, hibernation will be delayed at least until the calling
+ // thread's egl_display_ptr is destroyed.
+ void onWindowSurfaceCreated();
+ void onWindowSurfaceDestroyed();
+
static egl_display_t* get(EGLDisplay dpy);
static EGLDisplay getFromNativeDisplay(EGLNativeDisplayType disp);
@@ -124,10 +134,16 @@
String8 mClientApiString;
String8 mExtensionString;
int32_t mWakeCount;
+ bool mHibernating;
+ bool mAttemptHibernation;
};
// ----------------------------------------------------------------------------
+// An egl_display_ptr is a kind of smart pointer for egl_display_t objects.
+// It doesn't refcount the egl_display_t, but does ensure that the underlying
+// EGL implementation is "awake" (not hibernating) and ready for use as long
+// as the egl_display_ptr exists.
class egl_display_ptr {
public:
explicit egl_display_ptr(egl_display_t* dpy): mDpy(dpy) {
@@ -141,12 +157,13 @@
// We only really need a C++11 move constructor, not a copy constructor.
// A move constructor would save an enter()/leave() pair on every EGL API
// call. But enabling -std=c++0x causes lots of errors elsewhere, so I
- // can't use a move constructor yet.
+ // can't use a move constructor until those are cleaned up.
//
// egl_display_ptr(egl_display_ptr&& other) {
// mDpy = other.mDpy;
// other.mDpy = NULL;
// }
+ //
egl_display_ptr(const egl_display_ptr& other): mDpy(other.mDpy) {
if (mDpy) {
mDpy->enter();
diff --git a/opengl/libs/EGL/egl_entries.in b/opengl/libs/EGL/egl_entries.in
index bdd2a7e..9feb716 100644
--- a/opengl/libs/EGL/egl_entries.in
+++ b/opengl/libs/EGL/egl_entries.in
@@ -67,3 +67,8 @@
EGL_ENTRY(EGLuint64NV, eglGetSystemTimeFrequencyNV, void)
EGL_ENTRY(EGLuint64NV, eglGetSystemTimeNV, void)
+
+/* IMG extensions */
+
+EGL_ENTRY(EGLBoolean, eglHibernateProcessIMG, void)
+EGL_ENTRY(EGLBoolean, eglAwakenProcessIMG, void)
\ No newline at end of file
diff --git a/opengl/libs/EGL/egl_object.cpp b/opengl/libs/EGL/egl_object.cpp
index b42b268..aaa5e72 100644
--- a/opengl/libs/EGL/egl_object.cpp
+++ b/opengl/libs/EGL/egl_object.cpp
@@ -63,6 +63,29 @@
// ----------------------------------------------------------------------------
+egl_surface_t::egl_surface_t(egl_display_t* dpy, EGLConfig config,
+ EGLNativeWindowType win, EGLSurface surface,
+ egl_connection_t const* cnx) :
+ egl_object_t(dpy), surface(surface), config(config), win(win), cnx(cnx)
+{
+ if (win) {
+ getDisplay()->onWindowSurfaceCreated();
+ }
+}
+
+egl_surface_t::~egl_surface_t() {
+ ANativeWindow* const window = win.get();
+ if (window != NULL) {
+ native_window_set_buffers_format(window, 0);
+ if (native_window_api_disconnect(window, NATIVE_WINDOW_API_EGL)) {
+ ALOGW("EGLNativeWindowType %p disconnect failed", window);
+ }
+ getDisplay()->onWindowSurfaceDestroyed();
+ }
+}
+
+// ----------------------------------------------------------------------------
+
egl_context_t::egl_context_t(EGLDisplay dpy, EGLContext context, EGLConfig config,
egl_connection_t const* cnx, int version) :
egl_object_t(get_display_nowake(dpy)), dpy(dpy), context(context),
diff --git a/opengl/libs/EGL/egl_object.h b/opengl/libs/EGL/egl_object.h
index d1162db..2a08424 100644
--- a/opengl/libs/EGL/egl_object.h
+++ b/opengl/libs/EGL/egl_object.h
@@ -127,23 +127,14 @@
class egl_surface_t : public egl_object_t {
protected:
- ~egl_surface_t() {
- ANativeWindow* const window = win.get();
- if (window != NULL) {
- native_window_set_buffers_format(window, 0);
- if (native_window_api_disconnect(window, NATIVE_WINDOW_API_EGL)) {
- ALOGW("EGLNativeWindowType %p disconnect failed", window);
- }
- }
- }
+ ~egl_surface_t();
public:
typedef egl_object_t::LocalRef<egl_surface_t, EGLSurface> Ref;
egl_surface_t(egl_display_t* dpy, EGLConfig config,
EGLNativeWindowType win, EGLSurface surface,
- egl_connection_t const* cnx) :
- egl_object_t(dpy), surface(surface), config(config), win(win), cnx(cnx)
- {}
+ egl_connection_t const* cnx);
+
EGLSurface surface;
EGLConfig config;
sp<ANativeWindow> win;