Fix some null warnings

[deliverable/tracecompass.git] / lttng / org.eclipse.tracecompass.lttng2.kernel.core / src / org / eclipse / tracecompass / internal / lttng2 / kernel / core / analysis / vm / module / VirtualMachineCpuAnalysis.java

/*******************************************************************************
 * Copyright (c) 2014, 2015 École Polytechnique de Montréal
 *
 * All rights reserved. This program and the accompanying materials are
 * made available under the terms of the Eclipse Public License v1.0 which
 * accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   Mohamad Gebai - Initial API and implementation
 *   Geneviève Bastien - Initial API and implementation
 *******************************************************************************/

package org.eclipse.tracecompass.internal.lttng2.kernel.core.analysis.vm.module;

import static org.eclipse.tracecompass.common.core.NonNullUtils.checkNotNull;

import java.util.Comparator;
import java.util.HashSet;
import java.util.Set;

import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.jdt.annotation.NonNull;
import org.eclipse.jdt.annotation.Nullable;
import org.eclipse.tracecompass.analysis.os.linux.core.kernelanalysis.KernelAnalysisModule;
import org.eclipse.tracecompass.analysis.os.linux.core.kernelanalysis.KernelThreadInformationProvider;
import org.eclipse.tracecompass.common.core.NonNullUtils;
import org.eclipse.tracecompass.internal.lttng2.kernel.core.analysis.vm.VcpuStateValues;
import org.eclipse.tracecompass.internal.lttng2.kernel.core.analysis.vm.VmAttributes;
import org.eclipse.tracecompass.statesystem.core.ITmfStateSystem;
import org.eclipse.tracecompass.statesystem.core.StateSystemUtils;
import org.eclipse.tracecompass.statesystem.core.exceptions.AttributeNotFoundException;
import org.eclipse.tracecompass.statesystem.core.exceptions.StateSystemDisposedException;
import org.eclipse.tracecompass.statesystem.core.interval.ITmfStateInterval;
import org.eclipse.tracecompass.statesystem.core.interval.TmfStateInterval;
import org.eclipse.tracecompass.statesystem.core.statevalue.ITmfStateValue;
import org.eclipse.tracecompass.statesystem.core.statevalue.TmfStateValue;
import org.eclipse.tracecompass.tmf.core.analysis.IAnalysisModule;
import org.eclipse.tracecompass.tmf.core.statesystem.ITmfStateProvider;
import org.eclipse.tracecompass.tmf.core.statesystem.TmfStateSystemAnalysisModule;
import org.eclipse.tracecompass.tmf.core.trace.ITmfTrace;
import org.eclipse.tracecompass.tmf.core.trace.TmfTraceManager;
import org.eclipse.tracecompass.tmf.core.trace.TmfTraceUtils;
import org.eclipse.tracecompass.tmf.core.trace.experiment.TmfExperiment;
import org.eclipse.tracecompass.tmf.core.trace.experiment.TmfExperimentUtils;

import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Multimap;
import com.google.common.collect.TreeMultimap;

/**
 * Module for the virtual machine CPU analysis. It tracks the status of the
 * virtual CPUs for each guest of the experiment.
 *
 * @author Mohamad Gebai
 * @author Geneviève Bastien
 */
public class VirtualMachineCpuAnalysis extends TmfStateSystemAnalysisModule {

    // TODO: Update with event layout when requirements are back */
    static final Set<String> REQUIRED_EVENTS = NonNullUtils.checkNotNull(ImmutableSet.of(
            // LttngStrings.SCHED_SWITCH
            ));

    /* State value for a preempted virtual CPU */
    private static final ITmfStateValue VCPU_PREEMPT_VALUE = TmfStateValue.newValueInt(VcpuStateValues.VCPU_PREEMPT);

    /**
     * Constructor
     */
    public VirtualMachineCpuAnalysis() {
        super();
    }

    @Override
    protected ITmfStateProvider createStateProvider() {
        ITmfTrace trace = getTrace();
        if (!(trace instanceof TmfExperiment)) {
            throw new IllegalStateException();
        }
        return new VirtualMachineStateProvider((TmfExperiment) trace);
    }

    @Override
    protected @NonNull StateSystemBackendType getBackendType() {
        return StateSystemBackendType.FULL;
    }

    @Override
    public String getHelpText() {
        return Messages.getMessage(Messages.VirtualMachineCPUAnalysis_Help);
    }

    @Override
    protected Iterable<IAnalysisModule> getDependentAnalyses() {
        Set<IAnalysisModule> modules = new HashSet<>();
        /* Depends on the LTTng Kernel analysis modules */
        for (ITmfTrace trace : TmfTraceManager.getTraceSet(getTrace())) {
            trace = checkNotNull(trace);
            for (KernelAnalysisModule module : TmfTraceUtils.getAnalysisModulesOfClass(trace, KernelAnalysisModule.class)) {
                modules.add(module);
            }
        }
        return modules;
    }

    private static Multimap<Integer, ITmfStateInterval> createThreadMultimap() {

        /*
         * Create the multimap for threads with the appropriate comparator
         * objects for keys and values
         */
        final Multimap<Integer, ITmfStateInterval> map = NonNullUtils.checkNotNull(TreeMultimap.<@NonNull Integer, @NonNull ITmfStateInterval> create(
                new Comparator<Integer>() {
                    @Override
                    public int compare(@Nullable Integer arg0, @Nullable Integer arg1) {
                        /*
                         * Keys do not have to be sorted, just use natural
                         * sorting
                         */
                        if (arg0 == null || arg1 == null) {
                            return -1;
                        }
                        return arg0.compareTo(arg1);
                    }
                }, new Comparator<ITmfStateInterval>() {
                    @Override
                    public int compare(@Nullable ITmfStateInterval arg0, @Nullable ITmfStateInterval arg1) {
                        if (arg0 == null || arg1 == null) {
                            return 0;
                        }
                        if (arg1.getStateValue() == VCPU_PREEMPT_VALUE && arg0.getStateValue() != VCPU_PREEMPT_VALUE) {
                            /*
                             * For VCPU_PREEMPT state values, the state has to
                             * be after any other state that it overlaps,
                             * because those intervals usually decorate the
                             * other intervals.
                             */
                            if (((Long) arg0.getEndTime()).compareTo(arg1.getStartTime()) < 0) {
                                return -1;
                            }
                            return ((Long) arg0.getStartTime()).compareTo(arg1.getEndTime());
                        }
                        /* Otherwise, we use ordering by start time */
                        return (((Long) arg0.getStartTime()).compareTo(arg1.getStartTime()));
                    }
                }));
        return map;
    }

    /**
     * Get the status intervals for the threads from a virtual machine. Those
     * intervals are correlated with the data from the virtual CPU's preemption
     * status.
     *
     * This method uses the Linux Kernel Analysis data for the thread's status
     * intervals.
     *
     * @param vmQuark
     *            The quark of the virtual machine
     * @param start
     *            The start time of the period to get the intervals from
     * @param end
     *            The end time of the period to get the intervals from
     * @param resolution
     *            The resolution
     * @param monitor
     *            A progress monitor for this task
     * @return A map of status intervals for the machine's threads, including
     *         preempted intervals. Intervals from the thread status and the CPU
     *         preemption status overlap and are ordered such that CPU
     *         preemption intervals are after any interval they overlap with
     */
    public Multimap<Integer, ITmfStateInterval> getUpdatedThreadIntervals(int vmQuark, long start, long end, long resolution, IProgressMonitor monitor) {

        final Multimap<Integer, ITmfStateInterval> map = createThreadMultimap();

        ITmfStateSystem ss = getStateSystem();
        if (ss == null) {
            return map;
        }
        ITmfTrace trace = getTrace();
        if (!(trace instanceof TmfExperiment)) {
            return map;
        }

        String vmHostId = NonNullUtils.checkNotNull(ss.getAttributeName(vmQuark));
        KernelAnalysisModule kernelModule = TmfExperimentUtils.getAnalysisModuleOfClassForHost((TmfExperiment) trace, vmHostId, KernelAnalysisModule.class);
        if (kernelModule == null) {
            return map;
        }

        /*
         * Initialize the map with the original status intervals from the kernel
         * module
         */
        for (Integer tid : KernelThreadInformationProvider.getThreadIds(kernelModule)) {
            map.putAll(tid, KernelThreadInformationProvider.getStatusIntervalsForThread(kernelModule, tid, start, end, resolution, monitor));
            if (monitor.isCanceled()) {
                return map;
            }
        }

        try {
            /* Correlate thread information with virtual CPU information */
            for (Integer vcpuQuark : ss.getSubAttributes(vmQuark, false)) {
                Long virtualCPU = Long.parseLong(ss.getAttributeName(vcpuQuark));
                Integer statusQuark = ss.getQuarkRelative(vcpuQuark, VmAttributes.STATUS);

                for (ITmfStateInterval cpuInterval : StateSystemUtils.queryHistoryRange(ss, statusQuark, start, end - 1, resolution, monitor)) {
                    ITmfStateValue stateValue = cpuInterval.getStateValue();
                    switch (stateValue.getType()) {
                    case INTEGER:
                        int value = stateValue.unboxInt();
                        /*
                         * If the current CPU is either preempted or in
                         * hypervisor mode, add preempted intervals to running
                         * processes
                         */
                        if ((value & (VcpuStateValues.VCPU_PREEMPT | VcpuStateValues.VCPU_VMM)) == 0) {
                            break;
                        }
                        Integer threadOnCpu = KernelThreadInformationProvider.getThreadOnCpu(kernelModule, virtualCPU, cpuInterval.getStartTime());
                        if (threadOnCpu != null) {
                            map.put(threadOnCpu, new TmfStateInterval(cpuInterval.getStartTime(), cpuInterval.getEndTime(), threadOnCpu, VCPU_PREEMPT_VALUE));
                        }
                        break;
                    case DOUBLE:
                    case LONG:
                    case NULL:
                    case STRING:
                    default:
                        break;
                    }

                }
            }
        } catch (AttributeNotFoundException | StateSystemDisposedException e) {
        }
        return NonNullUtils.checkNotNull(map);
    }

}