org.eclipse.linuxtools.lttng2.ust.core/src/org/eclipse/linuxtools/internal/lttng2/ust/core/trace/callstack/LttngUstCallStackProvider.java

   1 /*******************************************************************************
   2  * Copyright (c) 2013 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  *******************************************************************************/
  12
  13 package org.eclipse.linuxtools.internal.lttng2.ust.core.trace.callstack;
  14
  15 import java.util.HashSet;
  16 import java.util.Set;
  17
  18 import org.eclipse.linuxtools.lttng2.ust.core.trace.LttngUstTrace;
  19 import org.eclipse.linuxtools.tmf.core.callstack.CallStackStateProvider;
  20 import org.eclipse.linuxtools.tmf.core.ctfadaptor.CtfTmfEvent;
  21 import org.eclipse.linuxtools.tmf.core.event.ITmfEvent;
  22 import org.eclipse.linuxtools.tmf.core.event.ITmfEventField;
  23
  24 /**
  25  * Callstack provider for LTTng-UST traces.
  26  *
  27  * If the traces contains 'func_entry' and 'func_exit' event (see the
  28  * lttng-ust-cyg-profile manpage), AND contains vtid and procname contexts, we
  29  * can use this information to populate the TMF Callstack View.
  30  *
  31  * Granted, most UST traces will not contain this information. In this case,
  32  * this will simply build an empty state system, and the view will remain
  33  * unavailable.
  34  *
  35  * @author Alexandre Montplaisir
  36  */
  37 public class LttngUstCallStackProvider extends CallStackStateProvider {
  38
  39     // ------------------------------------------------------------------------
  40     // Event strings
  41     // ------------------------------------------------------------------------
  42
  43     /** Name of the fake field for the vtid contexts */
  44     private static final String CONTEXT_VTID = "context._vtid"; //$NON-NLS-1$
  45
  46     /** Name of the fake field for the procname context */
  47     private static final String CONTEXT_PROCNAME = "context._procname"; //$NON-NLS-1$
  48
  49     /** Field name for the target function address */
  50     private static final String FIELD_ADDR = "addr"; //$NON-NLS-1$
  51
  52     /** Event names indicating function entry */
  53     private static final Set<String> FUNC_ENTRY_EVENTS = new HashSet<String>();
  54
  55     /** Event names indicating function exit */
  56     private static final Set<String> FUNC_EXIT_EVENTS = new HashSet<String>();
  57
  58     static {
  59         /* This seems overkill, but it will be checked every event. Gotta go FAST! */
  60         FUNC_ENTRY_EVENTS.add("lttng_ust_cyg_profile:func_entry"); //$NON-NLS-1$
  61         FUNC_ENTRY_EVENTS.add("lttng_ust_cyg_profile_fast:func_entry"); //$NON-NLS-1$
  62
  63         FUNC_EXIT_EVENTS.add("lttng_ust_cyg_profile:func_exit"); //$NON-NLS-1$
  64         FUNC_EXIT_EVENTS.add("lttng_ust_cyg_profile_fast:func_exit"); //$NON-NLS-1$
  65     }
  66
  67     /**
  68      * Version number of this state provider. Please bump this if you modify
  69      * the contents of the generated state history in some way.
  70      */
  71     private static final int VERSION = 1;
  72
  73     // ------------------------------------------------------------------------
  74     // Constructor
  75     // ------------------------------------------------------------------------
  76
  77     /**
  78      * Constructor
  79      *
  80      * @param trace
  81      *            The UST trace
  82      */
  83     public LttngUstCallStackProvider(LttngUstTrace trace) {
  84         super(trace);
  85     }
  86
  87     // ------------------------------------------------------------------------
  88     // Methods from AbstractTmfStateProvider
  89     // ------------------------------------------------------------------------
  90
  91     @Override
  92     public LttngUstTrace getTrace() {
  93         /* Type is enforced by the constructor */
  94         return (LttngUstTrace) super.getTrace();
  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     @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(CONTEXT_VTID) == null ||
 123                 content.getField(CONTEXT_PROCNAME) == null) {
 124             return false;
 125         }
 126         return true;
 127     }
 128
 129     @Override
 130     public String functionEntry(ITmfEvent event) {
 131         String eventName = ((CtfTmfEvent) event).getEventName();
 132         if (!FUNC_ENTRY_EVENTS.contains(eventName)) {
 133             return null;
 134         }
 135         Long address = (Long) event.getContent().getField(FIELD_ADDR).getValue();
 136         return Long.toHexString(address);
 137     }
 138
 139     @Override
 140     public String functionExit(ITmfEvent event) {
 141         String eventName = ((CtfTmfEvent) event).getEventName();
 142         if (!FUNC_EXIT_EVENTS.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(FIELD_ADDR);
 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     public String getThreadName(ITmfEvent event) {
 159         /* Class type and content was already checked if we get called here */
 160         ITmfEventField content = ((CtfTmfEvent) event).getContent();
 161         String procName = (String) content.getField(CONTEXT_PROCNAME).getValue();
 162         Long vtid = (Long) content.getField(CONTEXT_VTID).getValue();
 163
 164         if (procName == null || vtid == null) {
 165             throw new IllegalStateException();
 166         }
 167
 168         return new String(procName + '-' + vtid.toString());
 169     }
 170 }