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| |
| <h5 class="subsubsection">15.4.10.7 Extensions for Ada Tasks</h5> |
| |
| <p><a name="index-Ada_002c-tasking-1070"></a> |
| Support for Ada tasks is analogous to that for threads (see <a href="Threads.html#Threads">Threads</a>). |
| <span class="sc">gdb</span> provides the following task-related commands: |
| |
| |
| <a name="index-info-tasks-1071"></a> |
| <dl><dt><code>info tasks</code><dd>This command shows a list of current Ada tasks, as in the following example: |
| |
| <pre class="smallexample"> (gdb) info tasks |
| ID TID P-ID Pri State Name |
| 1 8088000 0 15 Child Activation Wait main_task |
| 2 80a4000 1 15 Accept Statement b |
| 3 809a800 1 15 Child Activation Wait a |
| * 4 80ae800 3 15 Runnable c |
| |
| </pre> |
| <p class="noindent">In this listing, the asterisk before the last task indicates it to be the |
| task currently being inspected. |
| |
| <dl> |
| <dt>ID<dd>Represents <span class="sc">gdb</span>'s internal task number. |
| |
| <br><dt>TID<dd>The Ada task ID. |
| |
| <br><dt>P-ID<dd>The parent's task ID (<span class="sc">gdb</span>'s internal task number). |
| |
| <br><dt>Pri<dd>The base priority of the task. |
| |
| <br><dt>State<dd>Current state of the task. |
| |
| <dl> |
| <dt><code>Unactivated</code><dd>The task has been created but has not been activated. It cannot be |
| executing. |
| |
| <br><dt><code>Runnable</code><dd>The task is not blocked for any reason known to Ada. (It may be waiting |
| for a mutex, though.) It is conceptually "executing" in normal mode. |
| |
| <br><dt><code>Terminated</code><dd>The task is terminated, in the sense of ARM 9.3 (5). Any dependents |
| that were waiting on terminate alternatives have been awakened and have |
| terminated themselves. |
| |
| <br><dt><code>Child Activation Wait</code><dd>The task is waiting for created tasks to complete activation. |
| |
| <br><dt><code>Accept Statement</code><dd>The task is waiting on an accept or selective wait statement. |
| |
| <br><dt><code>Waiting on entry call</code><dd>The task is waiting on an entry call. |
| |
| <br><dt><code>Async Select Wait</code><dd>The task is waiting to start the abortable part of an asynchronous |
| select statement. |
| |
| <br><dt><code>Delay Sleep</code><dd>The task is waiting on a select statement with only a delay |
| alternative open. |
| |
| <br><dt><code>Child Termination Wait</code><dd>The task is sleeping having completed a master within itself, and is |
| waiting for the tasks dependent on that master to become terminated or |
| waiting on a terminate Phase. |
| |
| <br><dt><code>Wait Child in Term Alt</code><dd>The task is sleeping waiting for tasks on terminate alternatives to |
| finish terminating. |
| |
| <br><dt><code>Accepting RV with </code><var>taskno</var><dd>The task is accepting a rendez-vous with the task <var>taskno</var>. |
| </dl> |
| |
| <br><dt>Name<dd>Name of the task in the program. |
| |
| </dl> |
| |
| <p><a name="index-info-task-_0040var_007btaskno_007d-1072"></a><br><dt><code>info task </code><var>taskno</var><dd>This command shows detailled informations on the specified task, as in |
| the following example: |
| <pre class="smallexample"> (gdb) info tasks |
| ID TID P-ID Pri State Name |
| 1 8077880 0 15 Child Activation Wait main_task |
| * 2 807c468 1 15 Runnable task_1 |
| (gdb) info task 2 |
| Ada Task: 0x807c468 |
| Name: task_1 |
| Thread: 0 |
| LWP: 0x1fac |
| Parent: 1 (main_task) |
| Base Priority: 15 |
| State: Runnable |
| </pre> |
| <br><dt><code>task</code><dd><a name="index-task_0040r_007b-_0028Ada_0029_007d-1073"></a><a name="index-current-Ada-task-ID-1074"></a>This command prints the ID of the current task. |
| |
| <pre class="smallexample"> (gdb) info tasks |
| ID TID P-ID Pri State Name |
| 1 8077870 0 15 Child Activation Wait main_task |
| * 2 807c458 1 15 Runnable t |
| (gdb) task |
| [Current task is 2] |
| </pre> |
| <br><dt><code>task </code><var>taskno</var><dd><a name="index-Ada-task-switching-1075"></a>This command is like the <code>thread </code><var>thread-id</var> |
| command (see <a href="Threads.html#Threads">Threads</a>). It switches the context of debugging |
| from the current task to the given task. |
| |
| <pre class="smallexample"> (gdb) info tasks |
| ID TID P-ID Pri State Name |
| 1 8077870 0 15 Child Activation Wait main_task |
| * 2 807c458 1 15 Runnable t |
| (gdb) task 1 |
| [Switching to task 1] |
| #0 0x8067726 in pthread_cond_wait () |
| (gdb) bt |
| #0 0x8067726 in pthread_cond_wait () |
| #1 0x8056714 in system.os_interface.pthread_cond_wait () |
| #2 0x805cb63 in system.task_primitives.operations.sleep () |
| #3 0x806153e in system.tasking.stages.activate_tasks () |
| #4 0x804aacc in un () at un.adb:5 |
| </pre> |
| <br><dt><code>break </code><var>location</var><code> task </code><var>taskno</var><dt><code>break </code><var>location</var><code> task </code><var>taskno</var><code> if ...</code><dd><a name="index-breakpoints-and-tasks_002c-in-Ada-1076"></a><a name="index-task-breakpoints_002c-in-Ada-1077"></a><a name="index-break-_0040dots_007b_007d-task-_0040var_007btaskno_007d_0040r_007b-_0028Ada_0029_007d-1078"></a>These commands are like the <code>break ... thread ...</code> |
| command (see <a href="Thread-Stops.html#Thread-Stops">Thread Stops</a>). The |
| <var>location</var> argument specifies source lines, as described |
| in <a href="Specify-Location.html#Specify-Location">Specify Location</a>. |
| |
| <p>Use the qualifier ‘<samp><span class="samp">task </span><var>taskno</var></samp>’ with a breakpoint command |
| to specify that you only want <span class="sc">gdb</span> to stop the program when a |
| particular Ada task reaches this breakpoint. The <var>taskno</var> is one of the |
| numeric task identifiers assigned by <span class="sc">gdb</span>, shown in the first |
| column of the ‘<samp><span class="samp">info tasks</span></samp>’ display. |
| |
| <p>If you do not specify ‘<samp><span class="samp">task </span><var>taskno</var></samp>’ when you set a |
| breakpoint, the breakpoint applies to <em>all</em> tasks of your |
| program. |
| |
| <p>You can use the <code>task</code> qualifier on conditional breakpoints as |
| well; in this case, place ‘<samp><span class="samp">task </span><var>taskno</var></samp>’ before the |
| breakpoint condition (before the <code>if</code>). |
| |
| <p>For example, |
| |
| <pre class="smallexample"> (gdb) info tasks |
| ID TID P-ID Pri State Name |
| 1 140022020 0 15 Child Activation Wait main_task |
| 2 140045060 1 15 Accept/Select Wait t2 |
| 3 140044840 1 15 Runnable t1 |
| * 4 140056040 1 15 Runnable t3 |
| (gdb) b 15 task 2 |
| Breakpoint 5 at 0x120044cb0: file test_task_debug.adb, line 15. |
| (gdb) cont |
| Continuing. |
| task # 1 running |
| task # 2 running |
| |
| Breakpoint 5, test_task_debug () at test_task_debug.adb:15 |
| 15 flush; |
| (gdb) info tasks |
| ID TID P-ID Pri State Name |
| 1 140022020 0 15 Child Activation Wait main_task |
| * 2 140045060 1 15 Runnable t2 |
| 3 140044840 1 15 Runnable t1 |
| 4 140056040 1 15 Delay Sleep t3 |
| </pre> |
| </dl> |
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