Fix thread priorities for unstarted threads.
Calls to Thread.setPriority for unstarted threads now behave
similar to dalvik. Note that there's still some inconsistent
behaviour carried over from dalvik.
- high priority threads from bg_non_interactive processes are
not always moved to the SP_FOREGROUND cgroup.
- we do not attempt to adjust the cgroup of a native thread
that's attaching.
Note that on android, the system_server will change the
cgroups for all running threads in a process when it moves
into the foreground and background. It's by design that
threads in a background process can request to be moved
to the foreground by setting a higher priority.
bug: 17893086
(cherry picked from commit 1bd326a5e2aaff06a5bcae9cb2c42a4e8de31401)
Change-Id: Iad362f7c5c8697c349f2b6d7fcba69a4e141883e
diff --git a/runtime/thread.cc b/runtime/thread.cc
index 7d24562..2c44f27 100644
--- a/runtime/thread.cc
+++ b/runtime/thread.cc
@@ -170,6 +170,9 @@
self->GetJniEnv()->DeleteGlobalRef(self->tlsPtr_.jpeer);
self->tlsPtr_.jpeer = nullptr;
self->SetThreadName(self->GetThreadName(soa)->ToModifiedUtf8().c_str());
+
+ mirror::ArtField* priorityField = soa.DecodeField(WellKnownClasses::java_lang_Thread_priority);
+ self->SetNativePriority(priorityField->GetInt(self->tlsPtr_.opeer));
Dbg::PostThreadStart(self);
// Invoke the 'run' method of our java.lang.Thread.
diff --git a/runtime/thread_android.cc b/runtime/thread_android.cc
index 73a9e54..d5db983 100644
--- a/runtime/thread_android.cc
+++ b/runtime/thread_android.cc
@@ -55,6 +55,13 @@
int newNice = kNiceValues[newPriority-1];
pid_t tid = GetTid();
+ // TODO: b/18249098 The code below is broken. It uses getpriority() as a proxy for whether a
+ // thread is already in the SP_FOREGROUND cgroup. This is not necessarily true for background
+ // processes, where all threads are in the SP_BACKGROUND cgroup. This means that callers will
+ // have to call setPriority twice to do what they want :
+ //
+ // Thread.setPriority(Thread.MIN_PRIORITY); // no-op wrt to cgroups
+ // Thread.setPriority(Thread.MAX_PRIORITY); // will actually change cgroups.
if (newNice >= ANDROID_PRIORITY_BACKGROUND) {
set_sched_policy(tid, SP_BACKGROUND);
} else if (getpriority(PRIO_PROCESS, tid) >= ANDROID_PRIORITY_BACKGROUND) {
diff --git a/test/051-thread/expected.txt b/test/051-thread/expected.txt
index 943d1df..54e34af 100644
--- a/test/051-thread/expected.txt
+++ b/test/051-thread/expected.txt
@@ -9,4 +9,6 @@
testSetName starting
testSetName running
testSetName finished
+testThreadPriorities starting
+testThreadPriorities finished
thread test done
diff --git a/test/051-thread/src/Main.java b/test/051-thread/src/Main.java
index 390685d..b81273e 100644
--- a/test/051-thread/src/Main.java
+++ b/test/051-thread/src/Main.java
@@ -20,12 +20,17 @@
* Test some basic thread stuff.
*/
public class Main {
+ static {
+ System.loadLibrary("arttest");
+ }
+
public static void main(String[] args) throws Exception {
System.out.println("thread test starting");
testThreadCapacity();
testThreadDaemons();
testSleepZero();
testSetName();
+ testThreadPriorities();
System.out.println("thread test done");
}
@@ -133,4 +138,53 @@
}
System.out.print("testSetName finished\n");
}
+
+ private static void testThreadPriorities() throws Exception {
+ System.out.print("testThreadPriorities starting\n");
+
+ PriorityStoringThread t1 = new PriorityStoringThread(false);
+ t1.setPriority(Thread.MAX_PRIORITY);
+ t1.start();
+ t1.join();
+ if (supportsThreadPriorities() && (t1.getNativePriority() != Thread.MAX_PRIORITY)) {
+ System.out.print("thread priority for t1 was " + t1.getNativePriority() +
+ " [expected Thread.MAX_PRIORITY]\n");
+ }
+
+ PriorityStoringThread t2 = new PriorityStoringThread(true);
+ t2.start();
+ t2.join();
+ if (supportsThreadPriorities() && (t2.getNativePriority() != Thread.MAX_PRIORITY)) {
+ System.out.print("thread priority for t2 was " + t2.getNativePriority() +
+ " [expected Thread.MAX_PRIORITY]\n");
+ }
+
+ System.out.print("testThreadPriorities finished\n");
+ }
+
+ private static native int getNativePriority();
+ private static native boolean supportsThreadPriorities();
+
+ static class PriorityStoringThread extends Thread {
+ private final boolean setPriority;
+ private volatile int nativePriority;
+
+ public PriorityStoringThread(boolean setPriority) {
+ this.setPriority = setPriority;
+ this.nativePriority = -1;
+ }
+
+ @Override
+ public void run() {
+ if (setPriority) {
+ setPriority(Thread.MAX_PRIORITY);
+ }
+
+ nativePriority = Main.getNativePriority();
+ }
+
+ public int getNativePriority() {
+ return nativePriority;
+ }
+ }
}
diff --git a/test/051-thread/thread_test.cc b/test/051-thread/thread_test.cc
new file mode 100644
index 0000000..2f5fffc
--- /dev/null
+++ b/test/051-thread/thread_test.cc
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "jni.h"
+#include "thread-inl.h"
+
+namespace art {
+
+extern "C" JNIEXPORT jint JNICALL Java_Main_getNativePriority(JNIEnv* env, jclass) {
+ return ThreadForEnv(env)->GetNativePriority();
+}
+
+extern "C" JNIEXPORT jboolean JNICALL Java_Main_supportsThreadPriorities(JNIEnv* env, jclass) {
+#if defined(HAVE_ANDROID_OS)
+ return JNI_TRUE;
+#else
+ return JNI_FALSE;
+#endif
+}
+
+} // namespace art
diff --git a/test/Android.libarttest.mk b/test/Android.libarttest.mk
index 55de1f3..c9c0475 100644
--- a/test/Android.libarttest.mk
+++ b/test/Android.libarttest.mk
@@ -24,6 +24,7 @@
004-ReferenceMap/stack_walk_refmap_jni.cc \
004-StackWalk/stack_walk_jni.cc \
004-UnsafeTest/unsafe_test.cc \
+ 051-thread/thread_test.cc \
116-nodex2oat/nodex2oat.cc \
117-nopatchoat/nopatchoat.cc \
118-noimage-dex2oat/noimage-dex2oat.cc