| 1 | /******************************************************************************* |
| 2 | * Copyright (c) 2014, 2015 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 | * François Rajotte - Initial API and implementation |
| 11 | * Geneviève Bastien - Revision of the initial implementation |
| 12 | *******************************************************************************/ |
| 13 | |
| 14 | package org.eclipse.tracecompass.analysis.os.linux.core.cpuusage; |
| 15 | |
| 16 | import static org.eclipse.tracecompass.common.core.NonNullUtils.checkNotNull; |
| 17 | |
| 18 | import java.util.HashMap; |
| 19 | import java.util.Map; |
| 20 | |
| 21 | import org.eclipse.jdt.annotation.Nullable; |
| 22 | import org.eclipse.tracecompass.analysis.os.linux.core.kernelanalysis.Attributes; |
| 23 | import org.eclipse.tracecompass.analysis.os.linux.core.trace.IKernelAnalysisEventLayout; |
| 24 | import org.eclipse.tracecompass.internal.analysis.os.linux.core.Activator; |
| 25 | import org.eclipse.tracecompass.statesystem.core.ITmfStateSystemBuilder; |
| 26 | import org.eclipse.tracecompass.statesystem.core.exceptions.AttributeNotFoundException; |
| 27 | import org.eclipse.tracecompass.statesystem.core.statevalue.ITmfStateValue; |
| 28 | import org.eclipse.tracecompass.statesystem.core.statevalue.TmfStateValue; |
| 29 | import org.eclipse.tracecompass.tmf.core.event.ITmfEvent; |
| 30 | import org.eclipse.tracecompass.tmf.core.event.ITmfEventField; |
| 31 | import org.eclipse.tracecompass.tmf.core.event.aspect.TmfCpuAspect; |
| 32 | import org.eclipse.tracecompass.tmf.core.statesystem.AbstractTmfStateProvider; |
| 33 | import org.eclipse.tracecompass.tmf.core.trace.ITmfTrace; |
| 34 | import org.eclipse.tracecompass.tmf.core.trace.TmfTraceUtils; |
| 35 | |
| 36 | /** |
| 37 | * Creates a state system with the total time spent on CPU for each thread and |
| 38 | * for each CPU from a kernel trace. |
| 39 | * |
| 40 | * This state system in itself keeps the total time on CPU since last time the |
| 41 | * process was scheduled out. The state system queries will only be accurate |
| 42 | * when the process is not in a running state. To have exact CPU usage when |
| 43 | * running, this state system needs to be used along the LTTng Kernel analysis. |
| 44 | * |
| 45 | * It requires only the 'sched_switch' events enabled on the trace. |
| 46 | * |
| 47 | * @author François Rajotte |
| 48 | */ |
| 49 | public class KernelCpuUsageStateProvider extends AbstractTmfStateProvider { |
| 50 | |
| 51 | private static final int VERSION = 2; |
| 52 | |
| 53 | /* For each CPU, maps the last time a thread was scheduled in */ |
| 54 | private final Map<Integer, Long> fLastStartTimes = new HashMap<>(); |
| 55 | private final long fTraceStart; |
| 56 | private final IKernelAnalysisEventLayout fLayout; |
| 57 | |
| 58 | /** |
| 59 | * Constructor |
| 60 | * |
| 61 | * @param trace |
| 62 | * The trace from which to get the CPU usage |
| 63 | * @param layout |
| 64 | * The event layout to use for this state provider. |
| 65 | */ |
| 66 | public KernelCpuUsageStateProvider(ITmfTrace trace, IKernelAnalysisEventLayout layout) { |
| 67 | super(trace, "Kernel CPU usage"); //$NON-NLS-1$ |
| 68 | fTraceStart = trace.getStartTime().getValue(); |
| 69 | fLayout = layout; |
| 70 | } |
| 71 | |
| 72 | // ------------------------------------------------------------------------ |
| 73 | // ITmfStateProvider |
| 74 | // ------------------------------------------------------------------------ |
| 75 | |
| 76 | @Override |
| 77 | public int getVersion() { |
| 78 | return VERSION; |
| 79 | } |
| 80 | |
| 81 | @Override |
| 82 | public KernelCpuUsageStateProvider getNewInstance() { |
| 83 | return new KernelCpuUsageStateProvider(this.getTrace(), this.fLayout); |
| 84 | } |
| 85 | |
| 86 | @Override |
| 87 | protected void eventHandle(@Nullable ITmfEvent event) { |
| 88 | if (event == null) { |
| 89 | return; |
| 90 | } |
| 91 | final String eventName = event.getName(); |
| 92 | |
| 93 | if (eventName.equals(fLayout.eventSchedSwitch())) { |
| 94 | Object cpuObj = TmfTraceUtils.resolveEventAspectOfClassForEvent(event.getTrace(), TmfCpuAspect.class, event); |
| 95 | if (cpuObj == null) { |
| 96 | /* We couldn't find any CPU information, ignore this event */ |
| 97 | return; |
| 98 | } |
| 99 | Integer cpu = (Integer) cpuObj; |
| 100 | |
| 101 | /* |
| 102 | * Fields: string prev_comm, int32 prev_tid, int32 prev_prio, int64 |
| 103 | * prev_state, string next_comm, int32 next_tid, int32 next_prio |
| 104 | */ |
| 105 | ITmfEventField content = event.getContent(); |
| 106 | long ts = event.getTimestamp().getValue(); |
| 107 | |
| 108 | Long prevTid = (Long) content.getField(fLayout.fieldPrevTid()).getValue(); |
| 109 | |
| 110 | try { |
| 111 | final ITmfStateSystemBuilder ss = checkNotNull(getStateSystemBuilder()); |
| 112 | |
| 113 | Integer currentCPUNode = ss.getQuarkRelativeAndAdd(getNodeCPUs(ss), cpu.toString()); |
| 114 | |
| 115 | /* |
| 116 | * This quark contains the value of the cumulative time spent on |
| 117 | * the source CPU by the currently running thread |
| 118 | */ |
| 119 | Integer cumulativeTimeQuark = ss.getQuarkRelativeAndAdd(currentCPUNode, prevTid.toString()); |
| 120 | Long startTime = fLastStartTimes.get(cpu); |
| 121 | /* |
| 122 | * If start time is null, we haven't seen the start of the |
| 123 | * process, so we assume beginning of the trace |
| 124 | */ |
| 125 | if (startTime == null) { |
| 126 | startTime = fTraceStart; |
| 127 | } |
| 128 | |
| 129 | /* |
| 130 | * We add the time from startTime until now to the cumulative |
| 131 | * time of the thread |
| 132 | */ |
| 133 | ITmfStateValue value = ss.queryOngoingState(cumulativeTimeQuark); |
| 134 | |
| 135 | /* |
| 136 | * Modify cumulative time for this CPU/TID combo: The total time |
| 137 | * changes when the process is scheduled out. Nothing happens |
| 138 | * when the process is scheduled in. |
| 139 | */ |
| 140 | long prevCumulativeTime = Math.max(0, value.unboxLong()); |
| 141 | long newCumulativeTime = prevCumulativeTime + (ts - startTime); |
| 142 | |
| 143 | value = TmfStateValue.newValueLong(newCumulativeTime); |
| 144 | ss.modifyAttribute(ts, value, cumulativeTimeQuark); |
| 145 | fLastStartTimes.put(cpu, ts); |
| 146 | |
| 147 | } catch (AttributeNotFoundException e) { |
| 148 | Activator.getDefault().logError("Attribute not found in LttngKernelCpuStateProvider", e); //$NON-NLS-1$ |
| 149 | } |
| 150 | |
| 151 | } |
| 152 | } |
| 153 | |
| 154 | /* Shortcut for the "current CPU" attribute node */ |
| 155 | private static int getNodeCPUs(ITmfStateSystemBuilder ssb) { |
| 156 | return ssb.getQuarkAbsoluteAndAdd(Attributes.CPUS); |
| 157 | } |
| 158 | |
| 159 | } |