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.statesystem.core.statevalue.ITmfStateValue;
  25 import org.eclipse.tracecompass.statesystem.core.statevalue.TmfStateValue;
  26 import org.eclipse.tracecompass.tmf.core.callstack.CallStackStateProvider;
  27 import org.eclipse.tracecompass.tmf.core.event.ITmfEvent;
  28 import org.eclipse.tracecompass.tmf.core.event.ITmfEventField;
  29 import org.eclipse.tracecompass.tmf.core.trace.ITmfTrace;
  30 import org.eclipse.tracecompass.tmf.ctf.core.event.CtfTmfEvent;
  31
  32 import com.google.common.collect.ImmutableSet;
  33
  34 /**
  35  * Callstack provider for LTTng-UST traces.
  36  *
  37  * If the traces contains 'func_entry' and 'func_exit' event (see the
  38  * lttng-ust-cyg-profile manpage), AND contains vtid and procname contexts, we
  39  * can use this information to populate the TMF Callstack View.
  40  *
  41  * Granted, most UST traces will not contain this information. In this case,
  42  * this will simply build an empty state system, and the view will remain
  43  * unavailable.
  44  *
  45  * @author Alexandre Montplaisir
  46  */
  47 @NonNullByDefault
  48 public class LttngUstCallStackProvider extends CallStackStateProvider {
  49
  50     /**
  51      * Version number of this state provider. Please bump this if you modify
  52      * the contents of the generated state history in some way.
  53      */
  54     private static final int VERSION = 3;
  55
  56     /** Event names indicating function entry */
  57     private final Set<String> funcEntryEvents;
  58
  59     /** Event names indicating function exit */
  60     private final Set<String> funcExitEvents;
  61
  62     private final ILttngUstEventLayout fLayout;
  63
  64     // ------------------------------------------------------------------------
  65     // Constructor
  66     // ------------------------------------------------------------------------
  67
  68     /**
  69      * Constructor
  70      *
  71      * @param trace
  72      *            The UST trace
  73      */
  74     public LttngUstCallStackProvider(ITmfTrace trace) {
  75         super(trace);
  76
  77         if (trace instanceof LttngUstTrace) {
  78             fLayout = ((LttngUstTrace) trace).getEventLayout();
  79         } else {
  80             /* For impostor trace types, assume they use the LTTng 2.0 layout */
  81             fLayout = LttngUst20EventLayout.getInstance();
  82         }
  83
  84         funcEntryEvents = ImmutableSet.of(
  85                 fLayout.eventCygProfileFuncEntry(),
  86                 fLayout.eventCygProfileFastFuncEntry());
  87
  88         funcExitEvents = ImmutableSet.of(
  89                 fLayout.eventCygProfileFuncExit(),
  90                 fLayout.eventCygProfileFastFuncExit());
  91     }
  92
  93     // ------------------------------------------------------------------------
  94     // Methods from AbstractTmfStateProvider
  95     // ------------------------------------------------------------------------
  96
  97     @Override
  98     public LttngUstCallStackProvider getNewInstance() {
  99         return new LttngUstCallStackProvider(getTrace());
 100     }
 101
 102     @Override
 103     public int getVersion() {
 104         return VERSION;
 105     }
 106
 107     // ------------------------------------------------------------------------
 108     // Methods from CallStackStateProvider
 109     // ------------------------------------------------------------------------
 110
 111     /**
 112      * Check that this event contains the required information we need to be
 113      * used in the call stack view. We need at least the "procname" and "vtid"
 114      * contexts.
 115      *
 116      * The "vpid" is useful too, but optional.
 117      */
 118     @Override
 119     protected boolean considerEvent(ITmfEvent event) {
 120         if (!(event instanceof CtfTmfEvent)) {
 121             return false;
 122         }
 123         ITmfEventField content = ((CtfTmfEvent) event).getContent();
 124         if (content.getField(fLayout.contextVtid()) == null ||
 125                 content.getField(fLayout.contextProcname()) == null) {
 126             return false;
 127         }
 128         return true;
 129     }
 130
 131     @Override
 132     public @Nullable ITmfStateValue functionEntry(ITmfEvent event) {
 133         String eventName = event.getName();
 134         if (!funcEntryEvents.contains(eventName)) {
 135             return null;
 136         }
 137         Long address = (Long) event.getContent().getField(fLayout.fieldAddr()).getValue();
 138         return TmfStateValue.newValueLong(address);
 139     }
 140
 141     @Override
 142     public @Nullable ITmfStateValue functionExit(ITmfEvent event) {
 143         String eventName = event.getName();
 144         if (!funcExitEvents.contains(eventName)) {
 145             return null;
 146         }
 147         /*
 148          * The 'addr' field may or may not be present in func_exit events,
 149          * depending on if cyg-profile.so or cyg-profile-fast.so was used.
 150          */
 151         ITmfEventField field = event.getContent().getField(fLayout.fieldAddr());
 152         if (field == null) {
 153             return TmfStateValue.nullValue();
 154         }
 155         Long address = (Long) field.getValue();
 156         return TmfStateValue.newValueLong(address);
 157     }
 158
 159     @Override
 160     protected int getProcessId(@NonNull ITmfEvent event) {
 161         /* The "vpid" context may not be present! We need to check */
 162         ITmfEventField content = event.getContent();
 163         ITmfEventField vpidContextField = content.getField(fLayout.contextVpid());
 164         if (vpidContextField == null) {
 165             return UNDEFINED_PID;
 166         }
 167         return ((Long) vpidContextField.getValue()).intValue();
 168     }
 169
 170     @Override
 171     protected long getThreadId(ITmfEvent event) {
 172         /* We checked earlier that the "vtid" context is present */
 173         ITmfEventField content = event.getContent();
 174         return ((Long) content.getField(fLayout.contextVtid()).getValue()).longValue();
 175     }
 176
 177     @Override
 178     public String getThreadName(ITmfEvent event) {
 179         /* We checked earlier that the "procname" context is present */
 180         ITmfEventField content = event.getContent();
 181         String procName = (String) content.getField(fLayout.contextProcname()).getValue();
 182         long vtid = getThreadId(event);
 183         return (procName + '-' + Long.toString(vtid));
 184     }
 185 }