1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
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 struct tcb_s *rtcb;
FAR struct tcb_s *tcb;
irqstate_t state;
int status;
/* 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 struct tcb_s*)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;
}
|