lttng/org.lttng.scope.lttng.kernel.core/src/org/lttng/scope/lttng/kernel/core/analysis/os/handlers/internal/ProcessForkHandler.java

   1 /*******************************************************************************
   2  * Copyright (c) 2015 Ericsson
   3  *
   4  * All rights reserved. This program and the accompanying materials
   5  * are made available under the terms of the Eclipse Public License v1.0
   6  * which accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *    Matthew Khouzam - Initial API and implementation
  11  *******************************************************************************/
  12
  13 package org.lttng.scope.lttng.kernel.core.analysis.os.handlers.internal;
  14
  15 import org.eclipse.tracecompass.tmf.core.event.ITmfEvent;
  16 import org.eclipse.tracecompass.tmf.core.event.ITmfEventField;
  17 import org.lttng.scope.lttng.kernel.core.analysis.os.Attributes;
  18 import org.lttng.scope.lttng.kernel.core.analysis.os.StateValues;
  19 import org.lttng.scope.lttng.kernel.core.trace.layout.ILttngKernelEventLayout;
  20
  21 import ca.polymtl.dorsal.libdelorean.ITmfStateSystemBuilder;
  22 import ca.polymtl.dorsal.libdelorean.exceptions.AttributeNotFoundException;
  23 import ca.polymtl.dorsal.libdelorean.statevalue.ITmfStateValue;
  24 import ca.polymtl.dorsal.libdelorean.statevalue.TmfStateValue;
  25
  26 /**
  27  * Fork Handler
  28  */
  29 public class ProcessForkHandler extends KernelEventHandler {
  30
  31     /**
  32      * Constructor
  33      *
  34      * @param layout
  35      *            event layout
  36      */
  37     public ProcessForkHandler(ILttngKernelEventLayout layout) {
  38         super(layout);
  39     }
  40
  41     @Override
  42     public void handleEvent(ITmfStateSystemBuilder ss, ITmfEvent event) throws AttributeNotFoundException {
  43         ITmfEventField content = event.getContent();
  44         Integer cpu = KernelEventHandlerUtils.getCpu(event);
  45         String childProcessName = (String) content.getField(getLayout().fieldChildComm()).getValue();
  46
  47         Integer parentTid = ((Long) content.getField(getLayout().fieldParentTid()).getValue()).intValue();
  48         Integer childTid = ((Long) content.getField(getLayout().fieldChildTid()).getValue()).intValue();
  49
  50         String parentThreadAttributeName = Attributes.buildThreadAttributeName(parentTid, cpu);
  51         if (parentThreadAttributeName == null) {
  52             return;
  53         }
  54
  55         String childThreadAttributeName = Attributes.buildThreadAttributeName(childTid, cpu);
  56         if (childThreadAttributeName == null) {
  57             return;
  58         }
  59
  60         final int threadsNode = KernelEventHandlerUtils.getNodeThreads(ss);
  61         Integer parentTidNode = ss.getQuarkRelativeAndAdd(threadsNode, parentThreadAttributeName);
  62         Integer childTidNode = ss.getQuarkRelativeAndAdd(threadsNode, childThreadAttributeName);
  63
  64
  65         /* Assign the PPID to the new process */
  66         int quark = ss.getQuarkRelativeAndAdd(childTidNode, Attributes.PPID);
  67         ITmfStateValue value = TmfStateValue.newValueInt(parentTid);
  68         long timestamp = KernelEventHandlerUtils.getTimestamp(event);
  69         ss.modifyAttribute(timestamp, value, quark);
  70
  71         /* Set the new process' exec_name */
  72         quark = ss.getQuarkRelativeAndAdd(childTidNode, Attributes.EXEC_NAME);
  73         value = TmfStateValue.newValueString(childProcessName);
  74         ss.modifyAttribute(timestamp, value, quark);
  75
  76         /*
  77          * Set the new process' status, it is initially in a blocked state. A
  78          * subsequent sched_wakeup_new will schedule it.
  79          */
  80         value = StateValues.PROCESS_STATUS_WAIT_BLOCKED_VALUE;
  81         ss.modifyAttribute(timestamp, value, childTidNode);
  82
  83         /* Set the process' syscall name, to be the same as the parent's */
  84         quark = ss.getQuarkRelativeAndAdd(parentTidNode, Attributes.SYSTEM_CALL);
  85         value = ss.queryOngoingState(quark);
  86         if (!value.isNull()) {
  87             quark = ss.getQuarkRelativeAndAdd(childTidNode, Attributes.SYSTEM_CALL);
  88             ss.modifyAttribute(timestamp, value, quark);
  89         }
  90
  91     }
  92 }