Move GC daemon locking logic into heap
Fixes deadlock caused by acquirng the mutator lock while
synchronizing on the daemon thread.
Bug: 18739541
Change-Id: Ib3ac3788081d3d471195a6e3a8ed163237616a4f
diff --git a/libart/src/main/java/dalvik/system/VMRuntime.java b/libart/src/main/java/dalvik/system/VMRuntime.java
index f778af0..58094d8 100644
--- a/libart/src/main/java/dalvik/system/VMRuntime.java
+++ b/libart/src/main/java/dalvik/system/VMRuntime.java
@@ -297,6 +297,8 @@
public native void trimHeap();
public native void concurrentGC();
+ public native void requestConcurrentGC();
+ public native void waitForConcurrentGCRequest();
/**
* Let the heap know of the new process state. This can change allocation and garbage collection
diff --git a/libart/src/main/java/java/lang/Daemons.java b/libart/src/main/java/java/lang/Daemons.java
index 726f782..d3f62c2 100644
--- a/libart/src/main/java/java/lang/Daemons.java
+++ b/libart/src/main/java/java/lang/Daemons.java
@@ -80,6 +80,10 @@
}
public synchronized void interrupt() {
+ interrupt(thread);
+ }
+
+ public synchronized void interrupt(Thread thread) {
if (thread == null) {
throw new IllegalStateException("not running");
}
@@ -99,7 +103,7 @@
if (threadToStop == null) {
throw new IllegalStateException("not running");
}
- threadToStop.interrupt();
+ interrupt(threadToStop);
while (true) {
try {
threadToStop.join();
@@ -311,34 +315,20 @@
}
}
- // Invoked by the GC to request that the HeapTrimmerDaemon thread attempt to trim the heap.
- public static void requestGC() {
- GCDaemon.INSTANCE.requestGC();
- }
-
private static class GCDaemon extends Daemon {
private static final GCDaemon INSTANCE = new GCDaemon();
- private static final AtomicBoolean atomicBoolean = new AtomicBoolean();
- public void requestGC() {
- if (atomicBoolean.getAndSet(true)) {
- return;
- }
- synchronized (this) {
- notify();
- }
- atomicBoolean.set(false);
+ // Overrides the Daemon.interupt method which is called from Daemons.stop.
+ public void interrupt(Thread thread) {
+ // Notifies the daemon thread.
+ VMRuntime.getRuntime().requestConcurrentGC();
}
@Override public void run() {
while (isRunning()) {
- try {
- synchronized (this) {
- // Wait until a request comes in.
- wait();
- }
+ VMRuntime.getRuntime().waitForConcurrentGCRequest();
+ if (isRunning()) {
VMRuntime.getRuntime().concurrentGC();
- } catch (InterruptedException ignored) {
}
}
}