/*
* Copyright (C) 2007 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.
*/
package dalvik.system;
import java.io.FileDescriptor;
import java.io.IOException;
/**
* Provides access to some VM-specific debug features. Though this class and
* many of its members are public, this class is meant to be wrapped in a more
* friendly way for use by application developers. On the Android platform, the
* recommended way to access this functionality is through the class
* <code>android.os.Debug</code>.
*
* @hide
*/
public final class VMDebug {
/**
* flag for startMethodTracing(), which adds the results from
* startAllocCounting to the trace key file.
*/
public static final int TRACE_COUNT_ALLOCS = 1;
/* constants for getAllocCount */
private static final int KIND_ALLOCATED_OBJECTS = 1<<0;
private static final int KIND_ALLOCATED_BYTES = 1<<1;
private static final int KIND_FREED_OBJECTS = 1<<2;
private static final int KIND_FREED_BYTES = 1<<3;
private static final int KIND_GC_INVOCATIONS = 1<<4;
private static final int KIND_CLASS_INIT_COUNT = 1<<5;
private static final int KIND_CLASS_INIT_TIME = 1<<6;
private static final int KIND_EXT_ALLOCATED_OBJECTS = 1<<12;
private static final int KIND_EXT_ALLOCATED_BYTES = 1<<13;
private static final int KIND_EXT_FREED_OBJECTS = 1<<14;
private static final int KIND_EXT_FREED_BYTES = 1<<15;
public static final int KIND_GLOBAL_ALLOCATED_OBJECTS =
KIND_ALLOCATED_OBJECTS;
public static final int KIND_GLOBAL_ALLOCATED_BYTES =
KIND_ALLOCATED_BYTES;
public static final int KIND_GLOBAL_FREED_OBJECTS =
KIND_FREED_OBJECTS;
public static final int KIND_GLOBAL_FREED_BYTES =
KIND_FREED_BYTES;
public static final int KIND_GLOBAL_GC_INVOCATIONS =
KIND_GC_INVOCATIONS;
public static final int KIND_GLOBAL_CLASS_INIT_COUNT =
KIND_CLASS_INIT_COUNT;
public static final int KIND_GLOBAL_CLASS_INIT_TIME =
KIND_CLASS_INIT_TIME;
public static final int KIND_GLOBAL_EXT_ALLOCATED_OBJECTS =
KIND_EXT_ALLOCATED_OBJECTS;
public static final int KIND_GLOBAL_EXT_ALLOCATED_BYTES =
KIND_EXT_ALLOCATED_BYTES;
public static final int KIND_GLOBAL_EXT_FREED_OBJECTS =
KIND_EXT_FREED_OBJECTS;
public static final int KIND_GLOBAL_EXT_FREED_BYTES =
KIND_EXT_FREED_BYTES;
public static final int KIND_THREAD_ALLOCATED_OBJECTS =
KIND_ALLOCATED_OBJECTS << 16;
public static final int KIND_THREAD_ALLOCATED_BYTES =
KIND_ALLOCATED_BYTES << 16;
public static final int KIND_THREAD_FREED_OBJECTS =
KIND_FREED_OBJECTS << 16;
public static final int KIND_THREAD_FREED_BYTES =
KIND_FREED_BYTES << 16;
public static final int KIND_THREAD_GC_INVOCATIONS =
KIND_GC_INVOCATIONS << 16;
public static final int KIND_THREAD_CLASS_INIT_COUNT =
KIND_CLASS_INIT_COUNT << 16;
public static final int KIND_THREAD_CLASS_INIT_TIME =
KIND_CLASS_INIT_TIME << 16;
public static final int KIND_THREAD_EXT_ALLOCATED_OBJECTS =
KIND_EXT_ALLOCATED_OBJECTS << 16;
public static final int KIND_THREAD_EXT_ALLOCATED_BYTES =
KIND_EXT_ALLOCATED_BYTES << 16;
public static final int KIND_THREAD_EXT_FREED_OBJECTS =
KIND_EXT_FREED_OBJECTS << 16;
public static final int KIND_THREAD_EXT_FREED_BYTES =
KIND_EXT_FREED_BYTES << 16;
public static final int KIND_ALL_COUNTS = 0xffffffff;
/* all methods are static */
private VMDebug() {}
/**
* Returns the time since the last known debugger activity.
*
* @return the time in milliseconds, or -1 if the debugger is not connected
*/
public static native long lastDebuggerActivity();
/**
* Determines if debugging is enabled in this VM. If debugging is not
* enabled, a debugger cannot be attached.
*
* @return true if debugging is enabled
*/
public static native boolean isDebuggingEnabled();
/**
* Determines if a debugger is currently attached.
*
* @return true if (and only if) a debugger is connected
*/
public static native boolean isDebuggerConnected();
/**
* Returns an array of strings that identify VM features. This is
* used by DDMS to determine what sorts of operations the VM can
* perform.
*/
public static native String[] getVmFeatureList();
/**
* Start method tracing with default name, size, and with <code>0</code>
* flags.
*
* @deprecated Not used, not needed.
*/
@Deprecated
public static void startMethodTracing() {
throw new UnsupportedOperationException();
}
/**
* Start method tracing, specifying a file name as well as a default
* buffer size. See <a
* href="{@docRoot}guide/developing/tools/traceview.html"> Running the
* Traceview Debugging Program</a> for information about reading
* trace files.
*
* <p>You can use either a fully qualified path and
* name, or just a name. If only a name is specified, the file will
* be created under the /sdcard/ directory. If a name is not given,
* the default is /sdcard/dmtrace.trace.</p>
*
* @param traceFileName name to give the trace file
* @param bufferSize the maximum size of both files combined. If passed
* as <code>0</code>, it defaults to 8MB.
* @param flags flags to control method tracing. The only one that
* is currently defined is {@link #TRACE_COUNT_ALLOCS}.
* @param samplingEnabled if true, sample profiling is enabled. Otherwise,
* method instrumentation is used.
* @param intervalUs the time between samples in microseconds when
* sampling is enabled.
*/
public static void startMethodTracing(String traceFileName, int bufferSize, int flags, boolean samplingEnabled, int intervalUs) {
startMethodTracingFilename(traceFileName, checkBufferSize(bufferSize), flags, samplingEnabled, intervalUs);
}
/**
* Like startMethodTracing(String, int, int), but taking an already-opened
* FileDescriptor in which the trace is written. The file name is also
* supplied simply for logging. Makes a dup of the file descriptor.
*/
public static void startMethodTracing(String traceFileName, FileDescriptor fd, int bufferSize, int flags, boolean samplingEnabled, int intervalUs) {
if (fd == null) {
throw new NullPointerException("fd == null");
}
startMethodTracingFd(traceFileName, fd, checkBufferSize(bufferSize), flags, samplingEnabled, intervalUs);
}
/**
* Starts method tracing without a backing file. When stopMethodTracing
* is called, the result is sent directly to DDMS. (If DDMS is not
* attached when tracing ends, the profiling data will be discarded.)
*/
public static void startMethodTracingDdms(int bufferSize, int flags, boolean samplingEnabled, int intervalUs) {
startMethodTracingDdmsImpl(checkBufferSize(bufferSize), flags, samplingEnabled, intervalUs);
}
private static int checkBufferSize(int bufferSize) {
if (bufferSize == 0) {
// Default to 8MB per the documentation.
bufferSize = 8 * 1024 * 1024;
}
if (bufferSize < 1024) {
throw new IllegalArgumentException("buffer size < 1024: " + bufferSize);
}
return bufferSize;
}
private static native void startMethodTracingDdmsImpl(int bufferSize, int flags, boolean samplingEnabled, int intervalUs);
private static native void startMethodTracingFd(String traceFileName, FileDescriptor fd, int bufferSize, int flags, boolean samplingEnabled, int intervalUs);
private static native void startMethodTracingFilename(String traceFileName, int bufferSize, int flags, boolean samplingEnabled, int intervalUs);
/**
* Determine whether method tracing is currently active and what type is
* active.
*/
public static native int getMethodTracingMode();
/**
* Stops method tracing.
*/
public static native void stopMethodTracing();
/**
* Starts sending Dalvik method trace info to the emulator.
*/
public static native void startEmulatorTracing();
/**
* Stops sending Dalvik method trace info to the emulator.
*/
public static native void stopEmulatorTracing();
/**
* Get an indication of thread CPU usage. The value returned indicates the
* amount of time that the current thread has spent executing code or
* waiting for certain types of I/O.
* <p>
* The time is expressed in nanoseconds, and is only meaningful when
* compared to the result from an earlier call. Note that nanosecond
* resolution does not imply nanosecond accuracy.
*
* @return the CPU usage. A value of -1 means the system does not support
* this feature.
*/
public static native long threadCpuTimeNanos();
/**
* Count the number and aggregate size of memory allocations between
* two points.
*/
public static native void startAllocCounting();
public static native void stopAllocCounting();
public static native int getAllocCount(int kind);
public static native void resetAllocCount(int kinds);
/**
* This method exists for binary compatibility. It was part of
* the allocation limits API which was removed in Android 3.0 (Honeycomb).
*/
@Deprecated
public static int setAllocationLimit(int limit) {
return -1;
}
/**
* This method exists for binary compatibility. It was part of
* the allocation limits API which was removed in Android 3.0 (Honeycomb).
*/
@Deprecated
public static int setGlobalAllocationLimit(int limit) {
return -1;
}
/**
* Count the number of instructions executed between two points.
*/
public static native void startInstructionCounting();
public static native void stopInstructionCounting();
public static native void getInstructionCount(int[] counts);
public static native void resetInstructionCount();
/**
* Dumps a list of loaded class to the log file.
*/
public static native void printLoadedClasses(int flags);
/**
* Gets the number of loaded classes.
*
* @return the number of loaded classes
*/
public static native int getLoadedClassCount();
/**
* Dumps "hprof" data to the specified file. This may cause a GC.
*
* The VM may create a temporary file in the same directory.
*
* @param filename Full pathname of output file (e.g. "/sdcard/dump.hprof").
* @throws UnsupportedOperationException if the VM was built without
* HPROF support.
* @throws IOException if an error occurs while opening or writing files.
*/
public static void dumpHprofData(String filename) throws IOException {
if (filename == null) {
throw new NullPointerException("filename == null");
}
dumpHprofData(filename, null);
}
/**
* Collects "hprof" heap data and sends it to DDMS. This may cause a GC.
*
* @throws UnsupportedOperationException if the VM was built without
* HPROF support.
*/
public static native void dumpHprofDataDdms();
/**
* Dumps "hprof" heap data to a file, by name or descriptor.
*
* @param fileName Name of output file. If fd is non-null, the
* file name is only used in log messages (and may be null).
* @param fd Descriptor of open file that will receive the output.
* If this is null, the fileName is used instead.
*/
public static native void dumpHprofData(String fileName, FileDescriptor fd)
throws IOException;
/**
* Primes the register map cache.
*/
public static native boolean cacheRegisterMap(String classAndMethodDesc);
/**
* Dumps the contents of the VM reference tables (e.g. JNI locals and
* globals) to the log file.
*/
public static native void dumpReferenceTables();
/**
* Crashes the VM. Seriously. Dumps the interpreter stack trace for
* the current thread and then aborts the VM so you can see the native
* stack trace. Useful for figuring out how you got somewhere when
* lots of native code is involved.
*/
public static native void crash();
/**
* Together with gdb, provide a handy way to stop the VM at user-tagged
* locations.
*/
public static native void infopoint(int id);
/*
* Fake method, inserted into dmtrace output when the garbage collector
* runs. Not actually called.
*/
private static void startGC() {}
/*
* Fake method, inserted into dmtrace output during class preparation
* (loading and linking, but not verification or initialization). Not
* actually called.
*/
private static void startClassPrep() {}
/**
* Counts the instances of a class.
*
* @param klass the class to be counted.
* @param assignable if false, direct instances of klass are
* counted. If true, instances that are
* assignable to klass, as defined by
* {@link Class#isAssignableFrom} are counted.
* @return the number of matching instances.
*/
public static native long countInstancesOfClass(Class klass, boolean assignable);
/**
* Export the heap per-space stats for dumpsys meminfo.
*
* The content of the array is:
*
* <pre>
* data[0] : the application heap space size
* data[1] : the application heap space allocated bytes
* data[2] : the application heap space free bytes
* data[3] : the zygote heap space size
* data[4] : the zygote heap space allocated size
* data[5] : the zygote heap space free size
* data[6] : the large object space size
* data[7] : the large object space allocated bytes
* data[8] : the large object space free bytes
* </pre>
*
* @param data the array into which the stats are written.
*/
public static native void getHeapSpaceStats(long[] data);
}