SurfaceFlinger: Dump on layer leaks
Every so often some process will leak layer references and
SurfaceFlinger will eventually crash (or refusing to create
new layers because of the max layer count). We never have
enough info to trace these down, and it becomes a horrible
game of chasing repro steps. While we currently have no
complaints about anything like this in T, a recent
12L bug serves as a timely reminder that we should get
this logging in BEFORE the next issue occurs, rather
than after.
Bug: 227286456
Test: Existing tests pass
Change-Id: I2c8b834c93a27204225b482fea1e54837204c9cf
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index fb5d738..ee4c41e 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -3603,6 +3603,23 @@
if (mNumLayers >= ISurfaceComposer::MAX_LAYERS) {
ALOGE("AddClientLayer failed, mNumLayers (%zu) >= MAX_LAYERS (%zu)", mNumLayers.load(),
ISurfaceComposer::MAX_LAYERS);
+ static_cast<void>(mScheduler->schedule([=] {
+ ALOGE("Dumping random sampling of on-screen layers: ");
+ mDrawingState.traverse([&](Layer *layer) {
+ // Aim to dump about 200 layers to avoid totally trashing
+ // logcat. On the other hand, if there really are 4096 layers
+ // something has gone totally wrong its probably the most
+ // useful information in logcat.
+ if (rand() % 20 == 13) {
+ ALOGE("Layer: %s", layer->getName().c_str());
+ }
+ });
+ for (Layer* offscreenLayer : mOffscreenLayers) {
+ if (rand() % 20 == 13) {
+ ALOGE("Offscreen-layer: %s", offscreenLayer->getName().c_str());
+ }
+ }
+ }));
return NO_MEMORY;
}