/*
* This file is part of the Jikes RVM project (http://jikesrvm.org).
*
* This file is licensed to You under the Eclipse Public License (EPL);
* You may not use this file except in compliance with the License. You
* may obtain a copy of the License at
*
* http://www.opensource.org/licenses/eclipse-1.0.php
*
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership.
*/
package org.mmtk.vm;
import org.vmmagic.pragma.Interruptible;
import org.vmmagic.pragma.Uninterruptible;
@Uninterruptible
public abstract class Statistics {
/**
* Read cycle counter. This has the same semantics
* as {@link java.lang.System#nanoTime()}.
*
* @return current time in nanoseconds
*/
public abstract long nanoTime();
/**
* Converts nanoseconds to milliseconds
*
* @param c time in nanoseconds
* @return time in milliseconds
*/
public abstract double nanosToMillis(long c);
/**
* Converts nanoseconds to seconds
*
* @param c time in nanoseconds
* @return time in seconds
*/
public abstract double nanosToSecs(long c);
/**
* Converts milliseconds to nanoseconds
*
* @param t time in milliseconds
* @return time in nanoseconds
*/
public abstract long millisToNanos(double t);
/**
* Convert seconds to nanoseconds
*
* @param t time in seconds
* @return time in nanoseconds
*/
public abstract long secsToNanos(double t);
/**
* Read the cycle counter
* @return number of cycles
*/
public abstract long cycles();
/**
* Initializes performance events.
*
* @param events the events to initialize. This is a comma-separated
* list of event names.
*/
@Interruptible
public abstract void perfEventInit(String events);
/**
* Reads a performance event value.
*
* @param counter the event's id
* @param values a buffer that will hold the return values of the
* read (3 64-bit values).
*/
public abstract void perfEventRead(int counter, long[] values);
}