lttng/org.lttng.scope.lttng.kernel.core/src/org/lttng/scope/lttng/kernel/core/analysis/os/handlers/internal/SchedWakeupHandler.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.lttng.scope.lttng.kernel.core.analysis.os.Attributes;
  17 import org.lttng.scope.lttng.kernel.core.analysis.os.StateValues;
  18 import org.lttng.scope.lttng.kernel.core.trace.layout.ILttngKernelEventLayout;
  19
  20 import ca.polymtl.dorsal.libdelorean.ITmfStateSystemBuilder;
  21 import ca.polymtl.dorsal.libdelorean.exceptions.AttributeNotFoundException;
  22 import ca.polymtl.dorsal.libdelorean.statevalue.ITmfStateValue;
  23 import ca.polymtl.dorsal.libdelorean.statevalue.TmfStateValue;
  24
  25 /**
  26  * Waking/wakeup handler.
  27  *
  28  * "sched_waking" and "sched_wakeup" tracepoints contain the same fields, and
  29  * apply the same state transitions in our model, so they can both use this
  30  * handler.
  31  */
  32 public class SchedWakeupHandler extends KernelEventHandler {
  33
  34     /**
  35      * Constructor
  36      * @param layout event layout
  37      */
  38     public SchedWakeupHandler(ILttngKernelEventLayout layout) {
  39         super(layout);
  40     }
  41
  42     @Override
  43     public void handleEvent(ITmfStateSystemBuilder ss, ITmfEvent event) throws AttributeNotFoundException {
  44         Integer cpu = KernelEventHandlerUtils.getCpu(event);
  45         final int tid = ((Long) event.getContent().getField(getLayout().fieldTid()).getValue()).intValue();
  46         final int prio = ((Long) event.getContent().getField(getLayout().fieldPrio()).getValue()).intValue();
  47         Long targetCpu = event.getContent().getFieldValue(Long.class, getLayout().fieldTargetCpu());
  48
  49         String threadAttributeName = Attributes.buildThreadAttributeName(tid, cpu);
  50         if (cpu == null || targetCpu == null || threadAttributeName == null) {
  51             return;
  52         }
  53
  54         final int threadNode = ss.getQuarkRelativeAndAdd(KernelEventHandlerUtils.getNodeThreads(ss), threadAttributeName);
  55
  56         /*
  57          * The process indicated in the event's payload is now ready to run.
  58          * Assign it to the "wait for cpu" state, but only if it was not already
  59          * running.
  60          */
  61         int status = ss.queryOngoingState(threadNode).unboxInt();
  62         ITmfStateValue value = null;
  63         long timestamp = KernelEventHandlerUtils.getTimestamp(event);
  64         if (status != StateValues.PROCESS_STATUS_RUN_SYSCALL &&
  65                 status != StateValues.PROCESS_STATUS_RUN_USERMODE) {
  66             value = StateValues.PROCESS_STATUS_WAIT_FOR_CPU_VALUE;
  67             ss.modifyAttribute(timestamp, value, threadNode);
  68         }
  69
  70         /* Set the thread's target run queue */
  71         int quark = ss.getQuarkRelativeAndAdd(threadNode, Attributes.CURRENT_CPU_RQ);
  72         value = TmfStateValue.newValueInt(targetCpu.intValue());
  73         ss.modifyAttribute(timestamp, value, quark);
  74
  75         /*
  76          * When a user changes a threads prio (e.g. with pthread_setschedparam),
  77          * it shows in ftrace with a sched_wakeup.
  78          */
  79         quark = ss.getQuarkRelativeAndAdd(threadNode, Attributes.PRIO);
  80         value = TmfStateValue.newValueInt(prio);
  81         ss.modifyAttribute(timestamp, value, quark);
  82     }
  83 }