Resync new repository with old repo r5166

git-svn-id: http://svn.code.sf.net/p/nuttx/code/trunk@5153 42af7a65-404d-4744-a932-0658087f49c3
2026-10-22 20:03:34 +08:00 · 2012-09-17 18:18:44 +00:00
commit 57623d42eb
5691 changed files with 1361853 additions and 0 deletions
@@ -0,0 +1,194 @@
+/****************************************************************************
+ * sched/task_delete.c
+ *
+ *   Copyright (C) 2007-2009, 2011-2012 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <stdlib.h>
+#include <sched.h>
+
+#include "os_internal.h"
+#ifndef CONFIG_DISABLE_SIGNALS
+# include "sig_internal.h"
+#endif
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: task_delete
+ *
+ * Description:
+ *   This function causes a specified task to cease to exist. Its  stack and
+ *   TCB will be deallocated.  This function is the companion to task_create().
+ *
+ *   The logic in this function only deletes non-running tasks.  If the 'pid'
+ *   parameter refers to to the currently runing task, then processing is
+ *   redirected to exit().
+ *
+ *   Control will still be returned to task_delete() after the exit() logic
+ *   finishes.  In fact, this function is the final function called all task
+ *   termination sequences.  Here are all possible exit scenarios:
+ *
+ *   - pthread_exit().  Calls exit()
+ *   - exit(). Calls _exit()
+ *   - _exit().  Calls task_deletecurrent() making the currently running task
+ *     non-running then calls task_delete() to terminate the non-running
+ *     task.
+ *   - task_delete()
+ *
+ * Inputs:
+ *   pid - The task ID of the task to delete.  A pid of zero
+ *         signifies the calling task.
+ *
+ * Return Value:
+ *   OK on success; or ERROR on failure
+ *
+ *   This function can fail if the provided pid does not correspond to a
+ *   task (errno is not set)
+ *
+ ****************************************************************************/
+
+int task_delete(pid_t pid)
+{
+  FAR _TCB  *rtcb;
+  FAR _TCB  *dtcb;
+  irqstate_t saved_state;
+  int        ret = ERROR;
+
+  /* Check if the task to delete is the calling task */
+
+  rtcb = (FAR _TCB*)g_readytorun.head;
+  if (pid == 0 || pid == rtcb->pid)
+    {
+      /* If it is, then what we really wanted to do was exit. Note that we
+       * don't bother to unlock the TCB since it will be going away.
+       */
+
+      exit(EXIT_SUCCESS);
+    }
+
+  /* Make sure the task does not become ready-to-run while we are futzing with
+   * its TCB by locking ourselves as the executing task.
+   */
+
+  sched_lock();
+
+  /* Find for the TCB associated with matching pid */
+
+  dtcb = sched_gettcb(pid);
+  if (!dtcb)
+    {
+      /* This pid does not correspond to any known task */
+
+      sched_unlock();
+      return ERROR;
+    }
+
+  /* Verify our internal sanity */
+
+  if (dtcb->task_state == TSTATE_TASK_RUNNING ||
+      dtcb->task_state >= NUM_TASK_STATES)
+    {
+      sched_unlock();
+      PANIC(OSERR_BADDELETESTATE);
+    }
+
+  /* Perform common task termination logic (flushing streams, calling
+   * functions registered by at_exit/on_exit, etc.).  We need to do
+   * this as early as possible so that higher level clean-up logic
+   * can run in a healthy tasking environment.
+   *
+   * In the case where the task exits via exit(), task_exithook()
+   * may be called twice.
+   *
+   * I suppose EXIT_SUCCESS is an appropriate return value???
+   */
+
+  task_exithook(dtcb, EXIT_SUCCESS);
+
+  /* Remove the task from the OS's tasks lists. */
+
+  saved_state = irqsave();
+  dq_rem((FAR dq_entry_t*)dtcb, (dq_queue_t*)g_tasklisttable[dtcb->task_state].list);
+  dtcb->task_state = TSTATE_TASK_INVALID;
+  irqrestore(saved_state);
+
+  /* At this point, the TCB should no longer be accessible to the system */
+
+  sched_unlock();
+
+  /* Since all tasks pass through this function as the final step in their
+   * exit sequence, this is an appropriate place to inform any instrumentation
+   * layer that the task no longer exists.
+   */
+
+  sched_note_stop(dtcb);
+
+  /* Deallocate its TCB */
+
+  sched_releasetcb(dtcb);
+  return ret;
+}
+