Divided _task_init() in several smaller functions that take fewer paramters. This was necessary to reduce the stack usage for the 8051/2 which has a tiny, 256 byte stack

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@58 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 25 insertions, 326 deletions

diff --git a/nuttx/sched/task_create.c b/nuttx/sched/task_create.c
index 07a6cab22..c3d1b453b 100644
--- a/nuttx/sched/task_create.c
+++ b/nuttx/sched/task_create.c
@@ -37,13 +37,12 @@
  * Included Files
  ************************************************************/
 
+#include <nuttx/config.h>
 #include <sys/types.h>
 #include <sched.h>
-#include <string.h>
 #include <errno.h>
 #include <debug.h>
 #include <nuttx/arch.h>
-#include <nuttx/os_external.h>
 #include "os_internal.h"
 
 /************************************************************
@@ -62,324 +61,15 @@
  * Private Variables
  ************************************************************/
 
-/* This is the name for un-named tasks */
-
-static FAR char g_noname[] = "no name";
-
 /************************************************************
  * Private Function Prototypes
  ************************************************************/
 
-static STATUS   task_assignpid(FAR _TCB* tcb);
-
 /************************************************************
  * Private Functions
  ************************************************************/
 
 /************************************************************
- * Name: task_assignpid
- *
- * Description:
- *   This function assigns the next unique task ID to a task.
- *
- * Inputs:
- *   tcb - TCB of task
- *
- * Return:
- *   OK on success; ERROR on failure (errno is not set)
- *
- ************************************************************/
-
-static STATUS task_assignpid(FAR _TCB *tcb)
-{
-  pid_t next_pid;
-  int   hash_ndx;
-  int   tries = 0;
-
-  /* Disable pre-emption.  This should provide sufficient protection
-   * for the following operation.
-   */
-
-  (void)sched_lock();
-
-  /* We'll try every allowable pid */
-
-  for (tries = 0; tries < CONFIG_MAX_TASKS; tries++)
-    {
-      /* Get the next process ID candidate */
-
-      next_pid = ++g_lastpid;
-
-      /* Verify that the next_pid is in the valid range */
-
-      if (next_pid <= 0)
-        {
-          g_lastpid = 1;
-          next_pid  = 1;
-        }
-
-      /* Get the hash_ndx associated with the next_pid */
-
-      hash_ndx = PIDHASH(next_pid);
-
-      /* Check if there is a (potential) duplicate of this pid */
-
-      if (!g_pidhash[hash_ndx].tcb)
-        {
-          g_pidhash[hash_ndx].tcb = tcb;
-          g_pidhash[hash_ndx].pid = next_pid;
-          tcb->pid = next_pid;
-          (void)sched_unlock();
-          return OK;
-        }
-    }
-
-  /* If we get here, then the g_pidhash[] table is completely full.
-   * We cannot allow another task to be started.
-   */
-
-  (void)sched_unlock();
-  return ERROR;
-}
-
-/************************************************************
- * Public Functions
- ************************************************************/
-
-/************************************************************
- * Name: task_start
- *
- * Description:
- *   This function is the low level entry point
- *   into the main thread of execution of a task.  It receives
- *   initial control when the task is started and calls main
- *   entry point of the newly started task.
- *
- * Inputs:
- *   None
- *
- * Return:
- *   None
- *
- ************************************************************/
-
-void task_start(void)
-{
-  FAR _TCB *tcb = (FAR _TCB*)g_readytorun.head;
-  int argc;
-
-  /* Count how many non-null arguments we are passing */
-
-  for (argc = 1; argc <= CONFIG_MAX_TASK_ARGS; argc++)
-    {
-       /* The first non-null argument terminates the list */
-
-       if (!tcb->argv[argc])
-         {
-           break;
-         }
-    }
-
-  /* Call the 'main' entry point passing argc and argv.  If/when
-   * the task returns,  */
-
-  exit(tcb->entry.main(argc, tcb->argv));
-}
-
-/************************************************************
- * Name: _task_init 
- *
- * Description:
- *   This functions initializes a Task Control Block (TCB)
- *   in preparation for starting a new thread.  _task_init()
- *   is an internal version of the task_init() function that
- *   has some  additional control arguments and task_init()
- *   is a wrapper function that creates a VxWorks-like user
- *   API. task_init() is, otherwise, not used by the OS.
- *
- *   _task_init() is called from task_init() and task_start().\
- *   It is also called from pthread_create() to create a 
- *   a pthread (distinguished by the pthread argument).
- *
- *   Unlike task_create(), task_init() does not activate the
- *   task.  This must be done by calling task_activate()
- *   afterward.
- *
- * Input Parameters:
- *   tcb        - Address of the new task's TCB
- *   name       - Name of the new task (not used)
- *   priority   - Priority of the new task
- *   entry      - Entry point of a new task
- *   main       - Application start point of the new task
- *   pthread    - TRUE is the task emulates pthread behavior
- *   argv       - A pointer to an array of input parameters.
- *                Up to CONFIG_MAX_TASK_ARG parameters may be
- *                provided. If fewer than CONFIG_MAX_TASK_ARG
- *                parameters are passed, the list should be
- *                terminated with a NULL argv[] value.
- *                If no parameters are required, argv may be NULL.
- *
- * Return Value:
- *  OK on success; ERROR on failure.
- *
- *  This function can only failure is it is unable to assign
- *  a new, unique task ID to the TCB (errno is not set).
- *
- ************************************************************/
-
-STATUS _task_init(FAR _TCB *tcb, const char *name, int priority,
-                  start_t start, main_t main, boolean pthread,
-                  char *argv[])
-{
-  STATUS ret;
-  int i;
-
-  /* Assign a unique task ID to the task. */
-
-  ret = task_assignpid(tcb);
-  if (ret == OK)
-    {
-      /* Save task priority and entry point in the TCB */
-
-      tcb->init_priority  = (ubyte)priority;
-      tcb->sched_priority = (ubyte)priority;
-      tcb->start          = start;
-      tcb->entry.main     = main;
-
-#if CONFIG_TASK_NAME_SIZE > 0
-      /* Give a name to the unnamed threads */
-
-      if (!name)
-        {
-          name = g_noname;
-        }
-
-      /* copy the name into the TCB */
-
-      strncpy(tcb->name, name, CONFIG_TASK_NAME_SIZE);
-#endif /* CONFIG_TASK_NAME_SIZE */
-
-      /* Save the arguments in the TCB */
-
-#if CONFIG_TASK_NAME_SIZE > 0
-      tcb->argv[0] = tcb->name;
-#else
-      tcb->argv[0] = g_noname;
-#endif
-
-      /* For pthreads, args are strictly pass-by-value; the char*
-       * arguments wrap some unknown value cast to char*.  However,
-       * for tasks, the life of the argument must be as long as
-       * the life of the task and the arguments must be strings.
-       * So for tasks, we have to to dup the strings.
-       */
-
-      if (!pthread)
-        {
-          /* The first NULL argument terminates the list of 
-           * arguments.  The argv pointer may be NULL if no
-           * parameters are passed.
-           */
-
-          i = 1;
-          if (argv)
-            {
-              for (; i < CONFIG_MAX_TASK_ARGS+1 && argv[i-1]; i++)
-                {
-                  tcb->argv[i] = strdup(argv[i-1]);
-                }
-            }
-        }
-      else
-        {
-          /* Mark this task as a pthread */
-
-          tcb->flags   |= TCB_FLAG_PTHREAD;
-
-          /* And just copy the argument. For pthreads, there
-           * is really only a single argument, argv[0].  It is
-           * copy as a value -- NOT duplicated.
-           */
-
-          i = 2;
-          tcb->argv[1]  = argv[0];
-        }
-
-      /* Nullify any unused argument storage */
-
-      for (; i < CONFIG_MAX_TASK_ARGS+1; i++)
-        {
-          tcb->argv[i] = NULL;
-        }
-
-      /* Initialize other (non-zero) elements of the TCB */
-
-#ifndef CONFIG_DISABLE_SIGNALS
-      tcb->sigprocmask  = ALL_SIGNAL_SET;
-#endif
-      tcb->task_state   = TSTATE_TASK_INVALID;
-
-      /* Initialize the processor-specific portion of the TCB */
-
-      up_initial_state(tcb);
-
-      /* Add the task to the inactive task list */
-
-      sched_lock();
-      dq_addfirst((FAR dq_entry_t*)tcb, &g_inactivetasks);
-      tcb->task_state = TSTATE_TASK_INACTIVE;
-      sched_unlock();
-    }
-
- return ret;
-}
-
-/************************************************************
- * Name: task_activate
- *
- * Description:
- *   This function activates tasks initialized by _task_init().
- *   Without activation, a task is ineligible for execution
- *   by the scheduler.
- *
- * Input Parameters:
- *   tcb - The TCB for the task for the task (same as the
- *         task_init argument.
- *
- * Return Value:
- *  Always returns OK
- *
- ************************************************************/
-
-STATUS task_activate(FAR _TCB *tcb)
-{
-#ifdef CONFIG_SCHED_INSTRUMENTATION
-  irqstate_t flags = irqsave();
-
-  /* Check if this is really a re-start */
-
-  if (tcb->task_state != TSTATE_TASK_INACTIVE)
-    {
-      /* Inform the instrumentation layer that the task
-       * has stopped
-       */
-
-      sched_note_stop(tcb);
-    }
-
-  /* Inform the instrumentation layer that the task
-   * has started
-   */
-
-  sched_note_start(tcb);
-  irqrestore(flags);
-#endif
-
-  up_unblock_task(tcb);
-  return OK;
-}
-
-/************************************************************
  * Name: task_create
  *
  * Description:
@@ -401,7 +91,13 @@ STATUS task_activate(FAR _TCB *tcb)
  *   priority   - Priority of the new task
  *   stack_size - size (in bytes) of the stack needed
  *   entry      - Entry point of a new task
- *   arg*       - Ten required task arguments to pass to func
+ *   arg        - A pointer to an array of input parameters.
+ *                Up to  CONFIG_MAX_TASK_ARG parameters may
+ *                be provided.  If fewer than CONFIG_MAX_TASK_ARG
+ *                parameters are passed, the list should be
+ *                terminated with a NULL argv[] value.
+ *                If no parameters are required, argv may be
+ *                NULL.
  *
  * Return Value:
  *   Returns the non-zero process ID of the new task or
@@ -452,29 +148,32 @@ int task_create(const char *name, int priority,
     }
 #endif
 
-   /* Initialize the task control block */
+  /* Initialize the task control block */
 
-   status = _task_init(tcb, name, priority, task_start, entry,
-                       FALSE, argv);
-   if (status != OK)
-     {
-       sched_releasetcb(tcb);
-       return ERROR;
-     }
+  status = task_schedsetup(tcb, priority, task_start, entry);
+  if (status != OK)
+    {
+      sched_releasetcb(tcb);
+      return ERROR;
+    }
+
+  /* Setup to pass parameters to the new task */
 
-   /* Get the assigned pid before we start the task */
+  (void)task_argsetup(tcb, name, FALSE, argv);
 
-   pid = (int)tcb->pid;
+  /* Get the assigned pid before we start the task */
 
-   /* Activate the task */
+  pid = (int)tcb->pid;
 
-   status = task_activate(tcb);
-   if (status != OK)
+  /* Activate the task */
+
+  status = task_activate(tcb);
+  if (status != OK)
     {
       dq_rem((FAR dq_entry_t*)tcb, &g_inactivetasks);
       sched_releasetcb(tcb);
       return ERROR;
     }
 
-   return pid;
+  return pid;
 }