Doubea Pierre / Mbed 2 deprecated HW3

Lab Checkoff

Dependencies:   SDFileSystem TextLCD mbed-rtos mbed wave_player FATFileSystem

mbed-rtos/rtx/rt_Mutex.c@0:67dbd54e60d4, 2013-11-13 (annotated)

Committer:
doubster
Date:
Wed Nov 13 20:00:28 2013 +0000
Revision:
0:67dbd54e60d4
Lab Checkoff

Who changed what in which revision?

UserRevisionLine numberNew contents of line
doubster 0:67dbd54e60d4 1 /*----------------------------------------------------------------------------
doubster 0:67dbd54e60d4 2 * RL-ARM - RTX
doubster 0:67dbd54e60d4 3 *----------------------------------------------------------------------------
doubster 0:67dbd54e60d4 4 * Name: RT_MUTEX.C
doubster 0:67dbd54e60d4 5 * Purpose: Implements mutex synchronization objects
doubster 0:67dbd54e60d4 6 * Rev.: V4.60
doubster 0:67dbd54e60d4 7 *----------------------------------------------------------------------------
doubster 0:67dbd54e60d4 8 *
doubster 0:67dbd54e60d4 9 * Copyright (c) 1999-2009 KEIL, 2009-2012 ARM Germany GmbH
doubster 0:67dbd54e60d4 10 * All rights reserved.
doubster 0:67dbd54e60d4 11 * Redistribution and use in source and binary forms, with or without
doubster 0:67dbd54e60d4 12 * modification, are permitted provided that the following conditions are met:
doubster 0:67dbd54e60d4 13 * - Redistributions of source code must retain the above copyright
doubster 0:67dbd54e60d4 14 * notice, this list of conditions and the following disclaimer.
doubster 0:67dbd54e60d4 15 * - Redistributions in binary form must reproduce the above copyright
doubster 0:67dbd54e60d4 16 * notice, this list of conditions and the following disclaimer in the
doubster 0:67dbd54e60d4 17 * documentation and/or other materials provided with the distribution.
doubster 0:67dbd54e60d4 18 * - Neither the name of ARM nor the names of its contributors may be used
doubster 0:67dbd54e60d4 19 * to endorse or promote products derived from this software without
doubster 0:67dbd54e60d4 20 * specific prior written permission.
doubster 0:67dbd54e60d4 21 *
doubster 0:67dbd54e60d4 22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
doubster 0:67dbd54e60d4 23 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
doubster 0:67dbd54e60d4 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
doubster 0:67dbd54e60d4 25 * ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS AND CONTRIBUTORS BE
doubster 0:67dbd54e60d4 26 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
doubster 0:67dbd54e60d4 27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
doubster 0:67dbd54e60d4 28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
doubster 0:67dbd54e60d4 29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
doubster 0:67dbd54e60d4 30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
doubster 0:67dbd54e60d4 31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
doubster 0:67dbd54e60d4 32 * POSSIBILITY OF SUCH DAMAGE.
doubster 0:67dbd54e60d4 33 *---------------------------------------------------------------------------*/
doubster 0:67dbd54e60d4 34
doubster 0:67dbd54e60d4 35 #include "rt_TypeDef.h"
doubster 0:67dbd54e60d4 36 #include "RTX_Config.h"
doubster 0:67dbd54e60d4 37 #include "rt_List.h"
doubster 0:67dbd54e60d4 38 #include "rt_Task.h"
doubster 0:67dbd54e60d4 39 #include "rt_Mutex.h"
doubster 0:67dbd54e60d4 40 #include "rt_HAL_CM.h"
doubster 0:67dbd54e60d4 41
doubster 0:67dbd54e60d4 42
doubster 0:67dbd54e60d4 43 /*----------------------------------------------------------------------------
doubster 0:67dbd54e60d4 44 * Functions
doubster 0:67dbd54e60d4 45 *---------------------------------------------------------------------------*/
doubster 0:67dbd54e60d4 46
doubster 0:67dbd54e60d4 47
doubster 0:67dbd54e60d4 48 /*--------------------------- rt_mut_init -----------------------------------*/
doubster 0:67dbd54e60d4 49
doubster 0:67dbd54e60d4 50 void rt_mut_init (OS_ID mutex) {
doubster 0:67dbd54e60d4 51 /* Initialize a mutex object */
doubster 0:67dbd54e60d4 52 P_MUCB p_MCB = mutex;
doubster 0:67dbd54e60d4 53
doubster 0:67dbd54e60d4 54 p_MCB->cb_type = MUCB;
doubster 0:67dbd54e60d4 55 p_MCB->prio = 0;
doubster 0:67dbd54e60d4 56 p_MCB->level = 0;
doubster 0:67dbd54e60d4 57 p_MCB->p_lnk = NULL;
doubster 0:67dbd54e60d4 58 p_MCB->owner = NULL;
doubster 0:67dbd54e60d4 59 }
doubster 0:67dbd54e60d4 60
doubster 0:67dbd54e60d4 61
doubster 0:67dbd54e60d4 62 /*--------------------------- rt_mut_delete ---------------------------------*/
doubster 0:67dbd54e60d4 63
doubster 0:67dbd54e60d4 64 #ifdef __CMSIS_RTOS
doubster 0:67dbd54e60d4 65 OS_RESULT rt_mut_delete (OS_ID mutex) {
doubster 0:67dbd54e60d4 66 /* Delete a mutex object */
doubster 0:67dbd54e60d4 67 P_MUCB p_MCB = mutex;
doubster 0:67dbd54e60d4 68 P_TCB p_TCB;
doubster 0:67dbd54e60d4 69
doubster 0:67dbd54e60d4 70 /* Restore owner task's priority. */
doubster 0:67dbd54e60d4 71 if (p_MCB->level != 0) {
doubster 0:67dbd54e60d4 72 p_MCB->owner->prio = p_MCB->prio;
doubster 0:67dbd54e60d4 73 if (p_MCB->owner != os_tsk.run) {
doubster 0:67dbd54e60d4 74 rt_resort_prio (p_MCB->owner);
doubster 0:67dbd54e60d4 75 }
doubster 0:67dbd54e60d4 76 }
doubster 0:67dbd54e60d4 77
doubster 0:67dbd54e60d4 78 while (p_MCB->p_lnk != NULL) {
doubster 0:67dbd54e60d4 79 /* A task is waiting for mutex. */
doubster 0:67dbd54e60d4 80 p_TCB = rt_get_first ((P_XCB)p_MCB);
doubster 0:67dbd54e60d4 81 rt_ret_val(p_TCB, 0/*osOK*/);
doubster 0:67dbd54e60d4 82 rt_rmv_dly(p_TCB);
doubster 0:67dbd54e60d4 83 p_TCB->state = READY;
doubster 0:67dbd54e60d4 84 rt_put_prio (&os_rdy, p_TCB);
doubster 0:67dbd54e60d4 85 }
doubster 0:67dbd54e60d4 86
doubster 0:67dbd54e60d4 87 if (os_rdy.p_lnk && (os_rdy.p_lnk->prio > os_tsk.run->prio)) {
doubster 0:67dbd54e60d4 88 /* preempt running task */
doubster 0:67dbd54e60d4 89 rt_put_prio (&os_rdy, os_tsk.run);
doubster 0:67dbd54e60d4 90 os_tsk.run->state = READY;
doubster 0:67dbd54e60d4 91 rt_dispatch (NULL);
doubster 0:67dbd54e60d4 92 }
doubster 0:67dbd54e60d4 93
doubster 0:67dbd54e60d4 94 p_MCB->cb_type = 0;
doubster 0:67dbd54e60d4 95
doubster 0:67dbd54e60d4 96 return (OS_R_OK);
doubster 0:67dbd54e60d4 97 }
doubster 0:67dbd54e60d4 98 #endif
doubster 0:67dbd54e60d4 99
doubster 0:67dbd54e60d4 100
doubster 0:67dbd54e60d4 101 /*--------------------------- rt_mut_release --------------------------------*/
doubster 0:67dbd54e60d4 102
doubster 0:67dbd54e60d4 103 OS_RESULT rt_mut_release (OS_ID mutex) {
doubster 0:67dbd54e60d4 104 /* Release a mutex object */
doubster 0:67dbd54e60d4 105 P_MUCB p_MCB = mutex;
doubster 0:67dbd54e60d4 106 P_TCB p_TCB;
doubster 0:67dbd54e60d4 107
doubster 0:67dbd54e60d4 108 if (p_MCB->level == 0 || p_MCB->owner != os_tsk.run) {
doubster 0:67dbd54e60d4 109 /* Unbalanced mutex release or task is not the owner */
doubster 0:67dbd54e60d4 110 return (OS_R_NOK);
doubster 0:67dbd54e60d4 111 }
doubster 0:67dbd54e60d4 112 if (--p_MCB->level != 0) {
doubster 0:67dbd54e60d4 113 return (OS_R_OK);
doubster 0:67dbd54e60d4 114 }
doubster 0:67dbd54e60d4 115 /* Restore owner task's priority. */
doubster 0:67dbd54e60d4 116 os_tsk.run->prio = p_MCB->prio;
doubster 0:67dbd54e60d4 117 if (p_MCB->p_lnk != NULL) {
doubster 0:67dbd54e60d4 118 /* A task is waiting for mutex. */
doubster 0:67dbd54e60d4 119 p_TCB = rt_get_first ((P_XCB)p_MCB);
doubster 0:67dbd54e60d4 120 #ifdef __CMSIS_RTOS
doubster 0:67dbd54e60d4 121 rt_ret_val(p_TCB, 0/*osOK*/);
doubster 0:67dbd54e60d4 122 #else
doubster 0:67dbd54e60d4 123 rt_ret_val(p_TCB, OS_R_MUT);
doubster 0:67dbd54e60d4 124 #endif
doubster 0:67dbd54e60d4 125 rt_rmv_dly (p_TCB);
doubster 0:67dbd54e60d4 126 /* A waiting task becomes the owner of this mutex. */
doubster 0:67dbd54e60d4 127 p_MCB->level = 1;
doubster 0:67dbd54e60d4 128 p_MCB->owner = p_TCB;
doubster 0:67dbd54e60d4 129 p_MCB->prio = p_TCB->prio;
doubster 0:67dbd54e60d4 130 /* Priority inversion, check which task continues. */
doubster 0:67dbd54e60d4 131 if (os_tsk.run->prio >= rt_rdy_prio()) {
doubster 0:67dbd54e60d4 132 rt_dispatch (p_TCB);
doubster 0:67dbd54e60d4 133 }
doubster 0:67dbd54e60d4 134 else {
doubster 0:67dbd54e60d4 135 /* Ready task has higher priority than running task. */
doubster 0:67dbd54e60d4 136 rt_put_prio (&os_rdy, os_tsk.run);
doubster 0:67dbd54e60d4 137 rt_put_prio (&os_rdy, p_TCB);
doubster 0:67dbd54e60d4 138 os_tsk.run->state = READY;
doubster 0:67dbd54e60d4 139 p_TCB->state = READY;
doubster 0:67dbd54e60d4 140 rt_dispatch (NULL);
doubster 0:67dbd54e60d4 141 }
doubster 0:67dbd54e60d4 142 }
doubster 0:67dbd54e60d4 143 else {
doubster 0:67dbd54e60d4 144 /* Check if own priority raised by priority inversion. */
doubster 0:67dbd54e60d4 145 if (rt_rdy_prio() > os_tsk.run->prio) {
doubster 0:67dbd54e60d4 146 rt_put_prio (&os_rdy, os_tsk.run);
doubster 0:67dbd54e60d4 147 os_tsk.run->state = READY;
doubster 0:67dbd54e60d4 148 rt_dispatch (NULL);
doubster 0:67dbd54e60d4 149 }
doubster 0:67dbd54e60d4 150 }
doubster 0:67dbd54e60d4 151 return (OS_R_OK);
doubster 0:67dbd54e60d4 152 }
doubster 0:67dbd54e60d4 153
doubster 0:67dbd54e60d4 154
doubster 0:67dbd54e60d4 155 /*--------------------------- rt_mut_wait -----------------------------------*/
doubster 0:67dbd54e60d4 156
doubster 0:67dbd54e60d4 157 OS_RESULT rt_mut_wait (OS_ID mutex, U16 timeout) {
doubster 0:67dbd54e60d4 158 /* Wait for a mutex, continue when mutex is free. */
doubster 0:67dbd54e60d4 159 P_MUCB p_MCB = mutex;
doubster 0:67dbd54e60d4 160
doubster 0:67dbd54e60d4 161 if (p_MCB->level == 0) {
doubster 0:67dbd54e60d4 162 p_MCB->owner = os_tsk.run;
doubster 0:67dbd54e60d4 163 p_MCB->prio = os_tsk.run->prio;
doubster 0:67dbd54e60d4 164 goto inc;
doubster 0:67dbd54e60d4 165 }
doubster 0:67dbd54e60d4 166 if (p_MCB->owner == os_tsk.run) {
doubster 0:67dbd54e60d4 167 /* OK, running task is the owner of this mutex. */
doubster 0:67dbd54e60d4 168 inc:p_MCB->level++;
doubster 0:67dbd54e60d4 169 return (OS_R_OK);
doubster 0:67dbd54e60d4 170 }
doubster 0:67dbd54e60d4 171 /* Mutex owned by another task, wait until released. */
doubster 0:67dbd54e60d4 172 if (timeout == 0) {
doubster 0:67dbd54e60d4 173 return (OS_R_TMO);
doubster 0:67dbd54e60d4 174 }
doubster 0:67dbd54e60d4 175 /* Raise the owner task priority if lower than current priority. */
doubster 0:67dbd54e60d4 176 /* This priority inversion is called priority inheritance. */
doubster 0:67dbd54e60d4 177 if (p_MCB->prio < os_tsk.run->prio) {
doubster 0:67dbd54e60d4 178 p_MCB->owner->prio = os_tsk.run->prio;
doubster 0:67dbd54e60d4 179 rt_resort_prio (p_MCB->owner);
doubster 0:67dbd54e60d4 180 }
doubster 0:67dbd54e60d4 181 if (p_MCB->p_lnk != NULL) {
doubster 0:67dbd54e60d4 182 rt_put_prio ((P_XCB)p_MCB, os_tsk.run);
doubster 0:67dbd54e60d4 183 }
doubster 0:67dbd54e60d4 184 else {
doubster 0:67dbd54e60d4 185 p_MCB->p_lnk = os_tsk.run;
doubster 0:67dbd54e60d4 186 os_tsk.run->p_lnk = NULL;
doubster 0:67dbd54e60d4 187 os_tsk.run->p_rlnk = (P_TCB)p_MCB;
doubster 0:67dbd54e60d4 188 }
doubster 0:67dbd54e60d4 189 rt_block(timeout, WAIT_MUT);
doubster 0:67dbd54e60d4 190 return (OS_R_TMO);
doubster 0:67dbd54e60d4 191 }
doubster 0:67dbd54e60d4 192
doubster 0:67dbd54e60d4 193
doubster 0:67dbd54e60d4 194 /*----------------------------------------------------------------------------
doubster 0:67dbd54e60d4 195 * end of file
doubster 0:67dbd54e60d4 196 *---------------------------------------------------------------------------*/
doubster 0:67dbd54e60d4 197
doubster 0:67dbd54e60d4 198