lttng/org.eclipse.tracecompass.lttng2.ust.core/src/org/eclipse/tracecompass/internal/lttng2/ust/core/callstack/LttngUstCallStackProvider.java

   1 /*******************************************************************************
   2  * Copyright (c) 2013, 2015 Ericsson
   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  *   Alexandre Montplaisir - Initial API and implementation
  11  *   Patrick Tasse - Add support for thread id
  12  *******************************************************************************/
  13
  14 package org.eclipse.tracecompass.internal.lttng2.ust.core.callstack;
  15
  16 import java.util.Set;
  17
  18 import org.eclipse.jdt.annotation.NonNull;
  19 import org.eclipse.jdt.annotation.NonNullByDefault;
  20 import org.eclipse.jdt.annotation.Nullable;
  21 import org.eclipse.tracecompass.internal.lttng2.ust.core.trace.layout.LttngUst20EventLayout;
  22 import org.eclipse.tracecompass.lttng2.ust.core.trace.LttngUstTrace;
  23 import org.eclipse.tracecompass.lttng2.ust.core.trace.layout.ILttngUstEventLayout;
  24 import org.eclipse.tracecompass.tmf.core.callstack.CallStackStateProvider;
  25 import org.eclipse.tracecompass.tmf.core.event.ITmfEvent;
  26 import org.eclipse.tracecompass.tmf.core.event.ITmfEventField;
  27 import org.eclipse.tracecompass.tmf.core.trace.ITmfTrace;
  28 import org.eclipse.tracecompass.tmf.ctf.core.event.CtfTmfEvent;
  29
  30 import com.google.common.collect.ImmutableSet;
  31
  32 /**
  33  * Callstack provider for LTTng-UST traces.
  34  *
  35  * If the traces contains 'func_entry' and 'func_exit' event (see the
  36  * lttng-ust-cyg-profile manpage), AND contains vtid and procname contexts, we
  37  * can use this information to populate the TMF Callstack View.
  38  *
  39  * Granted, most UST traces will not contain this information. In this case,
  40  * this will simply build an empty state system, and the view will remain
  41  * unavailable.
  42  *
  43  * @author Alexandre Montplaisir
  44  */
  45 @NonNullByDefault
  46 public class LttngUstCallStackProvider extends CallStackStateProvider {
  47
  48     /**
  49      * Version number of this state provider. Please bump this if you modify
  50      * the contents of the generated state history in some way.
  51      */
  52     private static final int VERSION = 3;
  53
  54     /** Event names indicating function entry */
  55     private final Set<String> funcEntryEvents;
  56
  57     /** Event names indicating function exit */
  58     private final Set<String> funcExitEvents;
  59
  60     private final ILttngUstEventLayout fLayout;
  61
  62     // ------------------------------------------------------------------------
  63     // Constructor
  64     // ------------------------------------------------------------------------
  65
  66     /**
  67      * Constructor
  68      *
  69      * @param trace
  70      *            The UST trace
  71      */
  72     public LttngUstCallStackProvider(ITmfTrace trace) {
  73         super(trace);
  74
  75         if (trace instanceof LttngUstTrace) {
  76             fLayout = ((LttngUstTrace) trace).getEventLayout();
  77         } else {
  78             /* For impostor trace types, assume they use the LTTng 2.0 layout */
  79             fLayout = LttngUst20EventLayout.getInstance();
  80         }
  81
  82         funcEntryEvents = ImmutableSet.of(
  83                 fLayout.eventCygProfileFuncEntry(),
  84                 fLayout.eventCygProfileFastFuncEntry());
  85
  86         funcExitEvents = ImmutableSet.of(
  87                 fLayout.eventCygProfileFuncExit(),
  88                 fLayout.eventCygProfileFastFuncExit());
  89     }
  90
  91     // ------------------------------------------------------------------------
  92     // Methods from AbstractTmfStateProvider
  93     // ------------------------------------------------------------------------
  94
  95     @Override
  96     public LttngUstCallStackProvider getNewInstance() {
  97         return new LttngUstCallStackProvider(getTrace());
  98     }
  99
 100     @Override
 101     public int getVersion() {
 102         return VERSION;
 103     }
 104
 105     // ------------------------------------------------------------------------
 106     // Methods from CallStackStateProvider
 107     // ------------------------------------------------------------------------
 108
 109     /**
 110      * Check that this event contains the required information we need to be
 111      * used in the call stack view. We need at least the "procname" and "vtid"
 112      * contexts.
 113      *
 114      * The "vpid" is useful too, but optional.
 115      */
 116     @Override
 117     protected boolean considerEvent(ITmfEvent event) {
 118         if (!(event instanceof CtfTmfEvent)) {
 119             return false;
 120         }
 121         ITmfEventField content = ((CtfTmfEvent) event).getContent();
 122         if (content.getField(fLayout.contextVtid()) == null ||
 123                 content.getField(fLayout.contextProcname()) == null) {
 124             return false;
 125         }
 126         return true;
 127     }
 128
 129     @Override
 130     public @Nullable String functionEntry(ITmfEvent event) {
 131         String eventName = event.getName();
 132         if (!funcEntryEvents.contains(eventName)) {
 133             return null;
 134         }
 135         Long address = (Long) event.getContent().getField(fLayout.fieldAddr()).getValue();
 136         return Long.toHexString(address);
 137     }
 138
 139     @Override
 140     public @Nullable String functionExit(ITmfEvent event) {
 141         String eventName = event.getName();
 142         if (!funcExitEvents.contains(eventName)) {
 143             return null;
 144         }
 145         /*
 146          * The 'addr' field may or may not be present in func_exit events,
 147          * depending on if cyg-profile.so or cyg-profile-fast.so was used.
 148          */
 149         ITmfEventField field = event.getContent().getField(fLayout.fieldAddr());
 150         if (field == null) {
 151             return CallStackStateProvider.UNDEFINED;
 152         }
 153         Long address = (Long) field.getValue();
 154         return Long.toHexString(address);
 155     }
 156
 157     @Override
 158     protected int getProcessId(@NonNull ITmfEvent event) {
 159         /* The "vpid" context may not be present! We need to check */
 160         ITmfEventField content = event.getContent();
 161         ITmfEventField vpidContextField = content.getField(fLayout.contextVpid());
 162         if (vpidContextField == null) {
 163             return UNDEFINED_PID;
 164         }
 165         return ((Long) vpidContextField.getValue()).intValue();
 166     }
 167
 168     @Override
 169     protected long getThreadId(ITmfEvent event) {
 170         /* We checked earlier that the "vtid" context is present */
 171         ITmfEventField content = event.getContent();
 172         return ((Long) content.getField(fLayout.contextVtid()).getValue()).longValue();
 173     }
 174
 175     @Override
 176     public String getThreadName(ITmfEvent event) {
 177         /* We checked earlier that the "procname" context is present */
 178         ITmfEventField content = event.getContent();
 179         String procName = (String) content.getField(fLayout.contextProcname()).getValue();
 180         long vtid = getThreadId(event);
 181         return (procName + '-' + Long.toString(vtid));
 182     }
 183 }