org.eclipse.tracecompass.lttng2.kernel.core/src/org/eclipse/tracecompass/internal/lttng2/kernel/core/analysis/vm/model/IVirtualMachineModel.java

   1 /*******************************************************************************
   2  * Copyright (c) 2014 École Polytechnique de Montréal
   3  *
   4  * All rights reserved. This program and the accompanying materials are
   5  * made available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *   Geneviève Bastien - Initial API and implementation
  11  *******************************************************************************/
  12
  13 package org.eclipse.tracecompass.internal.lttng2.kernel.core.analysis.vm.model;
  14
  15 import java.util.Set;
  16
  17 import org.eclipse.jdt.annotation.Nullable;
  18 import org.eclipse.tracecompass.analysis.os.linux.core.model.HostThread;
  19 import org.eclipse.tracecompass.tmf.core.event.ITmfEvent;
  20
  21 /**
  22  * Interface that represents the model of an hypervisor. Each hypervisor (or
  23  * tracing method for an hypervisor) should implement this.
  24  *
  25  * @author Geneviève Bastien
  26  */
  27 public interface IVirtualMachineModel {
  28
  29     /**
  30      * Get the machine that ran this event
  31      *
  32      * @param event
  33      *            The trace event
  34      * @return The machine this event was run on or {@code null} if the machine
  35      *         is not one belonging to this model.
  36      */
  37     @Nullable
  38     VirtualMachine getCurrentMachine(ITmfEvent event);
  39
  40     /**
  41      * Get a the set of events required for this model to apply.
  42      *
  43      * TODO: This should be updated to something else to fit the event layout
  44      * generic linux model
  45      *
  46      * @return The set of required events for this model
  47      */
  48     Set<String> getRequiredEvents();
  49
  50     /**
  51      * Get the virtual CPU that is entering hypervisor mode with this event.
  52      *
  53      * "Hypervisor mode" means the virtual CPU of the guest is running on the
  54      * host, but it is not running code from the guest, but rather other tasks
  55      * from the hypervisor. When hypervisor mode is entered, the process on the
  56      * host stops running guest code, so from the guest point of view, the
  57      * thread running on this CPU is preempted.
  58      *
  59      * @param event
  60      *            The event being handled
  61      * @param ht
  62      *            The current thread this event belongs to
  63      * @return The virtual CPU entering hypervisor mode or {@code null} if the
  64      *         hypervisor is not being entered with this event.
  65      */
  66     @Nullable
  67     VirtualCPU getVCpuEnteringHypervisorMode(ITmfEvent event, HostThread ht);
  68
  69     /**
  70      * Get the virtual CPU that is exiting hypervisor mode with this event.
  71      *
  72      * "Hypervisor mode" means the virtual CPU of the guest is running on the
  73      * host, but it is not running code from the guest, but rather other tasks
  74      * from the hypervisor. When hypervisor mode is exited, the process on the
  75      * host runs guest code, so from the guest point of view, the thread running
  76      * on this CPU is actively running.
  77      *
  78      * @param event
  79      *            The event being handled
  80      * @param ht
  81      *            The current thread this event belongs to
  82      * @return The virutal CPU exiting hypervisor mode or {@code null} if the
  83      *         hypervisor is not exiting with this event.
  84      */
  85     @Nullable
  86     VirtualCPU getVCpuExitingHypervisorMode(ITmfEvent event, HostThread ht);
  87
  88     /**
  89      * Get the virtual CPU from a guest that corresponds to a specific thread
  90      * from the host
  91      *
  92      * @param event
  93      *            The event being handled
  94      * @param ht
  95      *            The current thread this event belongs to. This thread should
  96      *            be running on the host.
  97      * @return The virtual CPU corresponding to this thread or {@code null} if
  98      *         no virtual CPU corresponds to the thread
  99      */
 100     @Nullable
 101     VirtualCPU getVirtualCpu(HostThread ht);
 102
 103     /**
 104      * Handles the event. This method will be called for each event required or
 105      * optional by the analysis, before any other handling is done on this
 106      * event.
 107      *
 108      * This is where each implementation of the model will build itself,
 109      * determine which guests are running on which hosts and get the necessary
 110      * information to be able to return the virtual CPUs requested by the other
 111      * methods of this interface.
 112      *
 113      * @param event
 114      *            The event being handled. It can come from any trace in the
 115      *            experiment
 116      */
 117     void handleEvent(ITmfEvent event);
 118
 119 }