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Diffstat (limited to 'nuttx/sched/task_restart.c')
| -rw-r--r-- | nuttx/sched/task_restart.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/nuttx/sched/task_restart.c b/nuttx/sched/task_restart.c new file mode 100644 index 000000000..6d9b84917 --- /dev/null +++ b/nuttx/sched/task_restart.c @@ -0,0 +1,184 @@ +/**************************************************************************** + * sched/task_restart.c + * + * Copyright (C) 2007, 2009, 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 <sched.h> +#include <nuttx/arch.h> +#include "os_internal.h" +#include "sig_internal.h" + +/**************************************************************************** + * Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Type Declarations + ****************************************************************************/ + +/**************************************************************************** + * Global Variables + ****************************************************************************/ + +/**************************************************************************** + * Private Variables + ****************************************************************************/ + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: task_restart + * + * Description: + * This function "restarts" a task. The task is first terminated and then + * reinitialized with same ID, priority, original entry point, stack size, + * and parameters it had when it was first started. + * + * Inputs: + * pid - The task ID of the task to delete. An ID of zero signifies the + * calling task. + * + * Return Value: + * OK on sucess; ERROR on failure. + * + * This function can fail if: + * (1) A pid of zero or the pid of the calling task is provided + * (functionality not implemented) + * (2) The pid is not associated with any task known to the system. + * + ****************************************************************************/ + +int task_restart(pid_t pid) +{ + FAR _TCB *rtcb; + FAR _TCB *tcb; + int status; + irqstate_t state; + + /* Make sure this task does not become ready-to-run while + * we are futzing with its TCB + */ + + sched_lock(); + + /* Check if the task to restart is the calling task */ + + rtcb = (FAR _TCB*)g_readytorun.head; + if ((pid == 0) || (pid == rtcb->pid)) + { + /* Not implemented */ + + return ERROR; + } + + /* We are restarting some other task than ourselves */ + + else + { + /* Find for the TCB associated with matching pid */ + + tcb = sched_gettcb(pid); + if (!tcb) + { + /* There is no TCB with this pid */ + + return ERROR; + } + + /* Remove the TCB from whatever list it is in. At this point, the + * TCB should no longer be accessible to the system + */ + + state = irqsave(); + dq_rem((FAR dq_entry_t*)tcb, (dq_queue_t*)g_tasklisttable[tcb->task_state].list); + tcb->task_state = TSTATE_TASK_INVALID; + irqrestore(state); + + /* Deallocate anything left in the TCB's queues */ + + sig_cleanup(tcb); /* Deallocate Signal lists */ + + /* Reset the current task priority */ + + tcb->sched_priority = tcb->init_priority; + + /* Reset the base task priority and the number of pending reprioritizations */ + +#ifdef CONFIG_PRIORITY_INHERITANCE + tcb->base_priority = tcb->init_priority; +# if CONFIG_SEM_NNESTPRIO > 0 + tcb->npend_reprio = 0; +# endif +#endif + + /* Re-initialize the processor-specific portion of the TCB + * This will reset the entry point and the start-up parameters + */ + + up_initial_state(tcb); + + /* Add the task to the inactive task list */ + + dq_addfirst((FAR dq_entry_t*)tcb, (dq_queue_t*)&g_inactivetasks); + tcb->task_state = TSTATE_TASK_INACTIVE; + + /* Activate the task */ + + status = task_activate(tcb); + if (status != OK) + { + dq_rem((FAR dq_entry_t*)tcb, (dq_queue_t*)&g_inactivetasks); + sched_releasetcb(tcb); + return ERROR; + } + } + + sched_unlock(); + return OK; +} |