contents/reference/lttng-modules/lttng-modules-tp-fast-assign.md

   1 ---
   2 id: lttng-modules-tp-fast-assign
   3 ---
   4
   5 This table describes possible entries for the `TP_fast_assign()` part
   6 of `LTTNG_TRACEPOINT_EVENT()`:
   7
   8 <table class="func-desc">
   9     <thead>
  10         <tr>
  11             <th>Macro</th>
  12             <th>Description/arguments</th>
  13         </tr>
  14     </thead>
  15     <tbody>
  16         <tr>
  17             <td>
  18                 <ul>
  19                     <li><code class="no-bg">tp_assign(<span class="arg">d</span>, <span class="arg">s</span>)</code></li>
  20                 </ul>
  21             </td>
  22             <td>
  23                 <p>
  24                     Assignment of C expression <code class="arg">s</code>
  25                     to tracepoint field <code class="arg">d</code>
  26                 </p>
  27                 <ul>
  28                     <li>
  29                         <code class="arg">d</code> name of destination
  30                         tracepoint field
  31                     </li>
  32                     <li>
  33                         <code class="arg">s</code> source C expression
  34                         (may refer to tracepoint arguments)
  35                     </li>
  36                 </ul>
  37             </td>
  38         </tr>
  39         <tr>
  40             <td>
  41                 <ul>
  42                     <li><code class="no-bg">tp_memcpy(<span class="arg">d</span>, <span class="arg">s</span>, <span class="arg">l</span>)</code></li>
  43                 </ul>
  44             </td>
  45             <td>
  46                 <p>
  47                     Memory copy of <code class="arg">l</code> bytes from
  48                     <code class="arg">s</code> to tracepoint field
  49                     <code class="arg">d</code> (use with array fields)
  50                 </p>
  51                 <ul>
  52                     <li>
  53                         <code class="arg">d</code> name of destination
  54                         tracepoint field
  55                     </li>
  56                     <li>
  57                         <code class="arg">s</code> source C expression
  58                         (may refer to tracepoint arguments)
  59                     </li>
  60                     <li>
  61                         <code class="arg">l</code> number of bytes to
  62                         copy
  63                     </li>
  64                 </ul>
  65             </td>
  66         </tr>
  67         <tr>
  68             <td>
  69                 <ul>
  70                     <li><code class="no-bg">tp_memcpy_from_user(<span class="arg">d</span>, <span class="arg">s</span>, <span class="arg">l</span>)</code></li>
  71                 </ul>
  72             </td>
  73             <td>
  74                 <p>
  75                     Memory copy of <code class="arg">l</code> bytes from
  76                     user space <code class="arg">s</code> to tracepoint field
  77                     <code class="arg">d</code> (use with array fields)
  78                 </p>
  79                 <ul>
  80                     <li>
  81                         <code class="arg">d</code> name of destination
  82                         tracepoint field
  83                     </li>
  84                     <li>
  85                         <code class="arg">s</code> source C expression
  86                         (may refer to tracepoint arguments)
  87                     </li>
  88                     <li>
  89                         <code class="arg">l</code> number of bytes to
  90                         copy
  91                     </li>
  92                 </ul>
  93             </td>
  94         </tr>
  95         <tr>
  96             <td>
  97                 <ul>
  98                     <li><code class="no-bg">tp_memcpy_dyn(<span class="arg">d</span>, <span class="arg">s</span>)</code></li>
  99                 </ul>
 100             </td>
 101             <td>
 102                 <p>
 103                     Memory copy of dynamically-sized array
 104                     from <code class="arg">s</code> to tracepoint field
 105                     <code class="arg">d</code>; number of bytes is
 106                     known from the field's length expression (use with
 107                     dynamically-sized array fields)
 108                 </p>
 109                 <ul>
 110                     <li>
 111                         <code class="arg">d</code> name of destination
 112                         tracepoint field
 113                     </li>
 114                     <li>
 115                         <code class="arg">s</code> source C expression
 116                         (may refer to tracepoint arguments)
 117                     </li>
 118                     <li>
 119                         <code class="arg">l</code> number of bytes to
 120                         copy
 121                     </li>
 122                 </ul>
 123             </td>
 124         </tr>
 125         <tr>
 126             <td>
 127                 <ul>
 128                     <li><code class="no-bg">tp_strcpy(<span class="arg">d</span>, <span class="arg">s</span>)</code></li>
 129                 </ul>
 130             </td>
 131             <td>
 132                 <p>
 133                     String copy of <code class="arg">s</code>
 134                     to tracepoint field <code class="arg">d</code>
 135                     (use with string fields)
 136                 </p>
 137                 <ul>
 138                     <li>
 139                         <code class="arg">d</code> name of destination
 140                         tracepoint field
 141                     </li>
 142                     <li>
 143                         <code class="arg">s</code> source C expression
 144                         (may refer to tracepoint arguments)
 145                     </li>
 146                 </ul>
 147             </td>
 148         </tr>
 149     </tbody>
 150 </table>