Alan Ffrench / Mbed 2 deprecated Experiment_2_5

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Dependencies:   mbed

mbed-rtos/rtx/rt_Semaphore.c@0:52468b19aa21, 2020-07-29 (annotated)

Committer:
alanffrench
Date:
Wed Jul 29 18:51:38 2020 +0000
Revision:
0:52468b19aa21
Threads

Who changed what in which revision?

UserRevisionLine numberNew contents of line
alanffrench 0:52468b19aa21 1 /*----------------------------------------------------------------------------
alanffrench 0:52468b19aa21 2 * RL-ARM - RTX
alanffrench 0:52468b19aa21 3 *----------------------------------------------------------------------------
alanffrench 0:52468b19aa21 4 * Name: RT_SEMAPHORE.C
alanffrench 0:52468b19aa21 5 * Purpose: Implements binary and counting semaphores
alanffrench 0:52468b19aa21 6 * Rev.: V4.60
alanffrench 0:52468b19aa21 7 *----------------------------------------------------------------------------
alanffrench 0:52468b19aa21 8 *
alanffrench 0:52468b19aa21 9 * Copyright (c) 1999-2009 KEIL, 2009-2012 ARM Germany GmbH
alanffrench 0:52468b19aa21 10 * All rights reserved.
alanffrench 0:52468b19aa21 11 * Redistribution and use in source and binary forms, with or without
alanffrench 0:52468b19aa21 12 * modification, are permitted provided that the following conditions are met:
alanffrench 0:52468b19aa21 13 * - Redistributions of source code must retain the above copyright
alanffrench 0:52468b19aa21 14 * notice, this list of conditions and the following disclaimer.
alanffrench 0:52468b19aa21 15 * - Redistributions in binary form must reproduce the above copyright
alanffrench 0:52468b19aa21 16 * notice, this list of conditions and the following disclaimer in the
alanffrench 0:52468b19aa21 17 * documentation and/or other materials provided with the distribution.
alanffrench 0:52468b19aa21 18 * - Neither the name of ARM nor the names of its contributors may be used
alanffrench 0:52468b19aa21 19 * to endorse or promote products derived from this software without
alanffrench 0:52468b19aa21 20 * specific prior written permission.
alanffrench 0:52468b19aa21 21 *
alanffrench 0:52468b19aa21 22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
alanffrench 0:52468b19aa21 23 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
alanffrench 0:52468b19aa21 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
alanffrench 0:52468b19aa21 25 * ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS AND CONTRIBUTORS BE
alanffrench 0:52468b19aa21 26 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
alanffrench 0:52468b19aa21 27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
alanffrench 0:52468b19aa21 28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
alanffrench 0:52468b19aa21 29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
alanffrench 0:52468b19aa21 30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
alanffrench 0:52468b19aa21 31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
alanffrench 0:52468b19aa21 32 * POSSIBILITY OF SUCH DAMAGE.
alanffrench 0:52468b19aa21 33 *---------------------------------------------------------------------------*/
alanffrench 0:52468b19aa21 34
alanffrench 0:52468b19aa21 35 #include "rt_TypeDef.h"
alanffrench 0:52468b19aa21 36 #include "RTX_Config.h"
alanffrench 0:52468b19aa21 37 #include "rt_System.h"
alanffrench 0:52468b19aa21 38 #include "rt_List.h"
alanffrench 0:52468b19aa21 39 #include "rt_Task.h"
alanffrench 0:52468b19aa21 40 #include "rt_Semaphore.h"
alanffrench 0:52468b19aa21 41 #include "rt_HAL_CM.h"
alanffrench 0:52468b19aa21 42
alanffrench 0:52468b19aa21 43
alanffrench 0:52468b19aa21 44 /*----------------------------------------------------------------------------
alanffrench 0:52468b19aa21 45 * Functions
alanffrench 0:52468b19aa21 46 *---------------------------------------------------------------------------*/
alanffrench 0:52468b19aa21 47
alanffrench 0:52468b19aa21 48
alanffrench 0:52468b19aa21 49 /*--------------------------- rt_sem_init -----------------------------------*/
alanffrench 0:52468b19aa21 50
alanffrench 0:52468b19aa21 51 void rt_sem_init (OS_ID semaphore, U16 token_count) {
alanffrench 0:52468b19aa21 52 /* Initialize a semaphore */
alanffrench 0:52468b19aa21 53 P_SCB p_SCB = semaphore;
alanffrench 0:52468b19aa21 54
alanffrench 0:52468b19aa21 55 p_SCB->cb_type = SCB;
alanffrench 0:52468b19aa21 56 p_SCB->p_lnk = NULL;
alanffrench 0:52468b19aa21 57 p_SCB->tokens = token_count;
alanffrench 0:52468b19aa21 58 }
alanffrench 0:52468b19aa21 59
alanffrench 0:52468b19aa21 60
alanffrench 0:52468b19aa21 61 /*--------------------------- rt_sem_delete ---------------------------------*/
alanffrench 0:52468b19aa21 62
alanffrench 0:52468b19aa21 63 #ifdef __CMSIS_RTOS
alanffrench 0:52468b19aa21 64 OS_RESULT rt_sem_delete (OS_ID semaphore) {
alanffrench 0:52468b19aa21 65 /* Delete semaphore */
alanffrench 0:52468b19aa21 66 P_SCB p_SCB = semaphore;
alanffrench 0:52468b19aa21 67 P_TCB p_TCB;
alanffrench 0:52468b19aa21 68
alanffrench 0:52468b19aa21 69 while (p_SCB->p_lnk != NULL) {
alanffrench 0:52468b19aa21 70 /* A task is waiting for token */
alanffrench 0:52468b19aa21 71 p_TCB = rt_get_first ((P_XCB)p_SCB);
alanffrench 0:52468b19aa21 72 rt_ret_val(p_TCB, 0);
alanffrench 0:52468b19aa21 73 rt_rmv_dly(p_TCB);
alanffrench 0:52468b19aa21 74 p_TCB->state = READY;
alanffrench 0:52468b19aa21 75 rt_put_prio (&os_rdy, p_TCB);
alanffrench 0:52468b19aa21 76 }
alanffrench 0:52468b19aa21 77
alanffrench 0:52468b19aa21 78 if (os_rdy.p_lnk && (os_rdy.p_lnk->prio > os_tsk.run->prio)) {
alanffrench 0:52468b19aa21 79 /* preempt running task */
alanffrench 0:52468b19aa21 80 rt_put_prio (&os_rdy, os_tsk.run);
alanffrench 0:52468b19aa21 81 os_tsk.run->state = READY;
alanffrench 0:52468b19aa21 82 rt_dispatch (NULL);
alanffrench 0:52468b19aa21 83 }
alanffrench 0:52468b19aa21 84
alanffrench 0:52468b19aa21 85 p_SCB->cb_type = 0;
alanffrench 0:52468b19aa21 86
alanffrench 0:52468b19aa21 87 return (OS_R_OK);
alanffrench 0:52468b19aa21 88 }
alanffrench 0:52468b19aa21 89 #endif
alanffrench 0:52468b19aa21 90
alanffrench 0:52468b19aa21 91
alanffrench 0:52468b19aa21 92 /*--------------------------- rt_sem_send -----------------------------------*/
alanffrench 0:52468b19aa21 93
alanffrench 0:52468b19aa21 94 OS_RESULT rt_sem_send (OS_ID semaphore) {
alanffrench 0:52468b19aa21 95 /* Return a token to semaphore */
alanffrench 0:52468b19aa21 96 P_SCB p_SCB = semaphore;
alanffrench 0:52468b19aa21 97 P_TCB p_TCB;
alanffrench 0:52468b19aa21 98
alanffrench 0:52468b19aa21 99 if (p_SCB->p_lnk != NULL) {
alanffrench 0:52468b19aa21 100 /* A task is waiting for token */
alanffrench 0:52468b19aa21 101 p_TCB = rt_get_first ((P_XCB)p_SCB);
alanffrench 0:52468b19aa21 102 #ifdef __CMSIS_RTOS
alanffrench 0:52468b19aa21 103 rt_ret_val(p_TCB, 1);
alanffrench 0:52468b19aa21 104 #else
alanffrench 0:52468b19aa21 105 rt_ret_val(p_TCB, OS_R_SEM);
alanffrench 0:52468b19aa21 106 #endif
alanffrench 0:52468b19aa21 107 rt_rmv_dly (p_TCB);
alanffrench 0:52468b19aa21 108 rt_dispatch (p_TCB);
alanffrench 0:52468b19aa21 109 }
alanffrench 0:52468b19aa21 110 else {
alanffrench 0:52468b19aa21 111 /* Store token. */
alanffrench 0:52468b19aa21 112 p_SCB->tokens++;
alanffrench 0:52468b19aa21 113 }
alanffrench 0:52468b19aa21 114 return (OS_R_OK);
alanffrench 0:52468b19aa21 115 }
alanffrench 0:52468b19aa21 116
alanffrench 0:52468b19aa21 117
alanffrench 0:52468b19aa21 118 /*--------------------------- rt_sem_wait -----------------------------------*/
alanffrench 0:52468b19aa21 119
alanffrench 0:52468b19aa21 120 OS_RESULT rt_sem_wait (OS_ID semaphore, U16 timeout) {
alanffrench 0:52468b19aa21 121 /* Obtain a token; possibly wait for it */
alanffrench 0:52468b19aa21 122 P_SCB p_SCB = semaphore;
alanffrench 0:52468b19aa21 123
alanffrench 0:52468b19aa21 124 if (p_SCB->tokens) {
alanffrench 0:52468b19aa21 125 p_SCB->tokens--;
alanffrench 0:52468b19aa21 126 return (OS_R_OK);
alanffrench 0:52468b19aa21 127 }
alanffrench 0:52468b19aa21 128 /* No token available: wait for one */
alanffrench 0:52468b19aa21 129 if (timeout == 0) {
alanffrench 0:52468b19aa21 130 return (OS_R_TMO);
alanffrench 0:52468b19aa21 131 }
alanffrench 0:52468b19aa21 132 if (p_SCB->p_lnk != NULL) {
alanffrench 0:52468b19aa21 133 rt_put_prio ((P_XCB)p_SCB, os_tsk.run);
alanffrench 0:52468b19aa21 134 }
alanffrench 0:52468b19aa21 135 else {
alanffrench 0:52468b19aa21 136 p_SCB->p_lnk = os_tsk.run;
alanffrench 0:52468b19aa21 137 os_tsk.run->p_lnk = NULL;
alanffrench 0:52468b19aa21 138 os_tsk.run->p_rlnk = (P_TCB)p_SCB;
alanffrench 0:52468b19aa21 139 }
alanffrench 0:52468b19aa21 140 rt_block(timeout, WAIT_SEM);
alanffrench 0:52468b19aa21 141 return (OS_R_TMO);
alanffrench 0:52468b19aa21 142 }
alanffrench 0:52468b19aa21 143
alanffrench 0:52468b19aa21 144
alanffrench 0:52468b19aa21 145 /*--------------------------- isr_sem_send ----------------------------------*/
alanffrench 0:52468b19aa21 146
alanffrench 0:52468b19aa21 147 void isr_sem_send (OS_ID semaphore) {
alanffrench 0:52468b19aa21 148 /* Same function as "os_sem"send", but to be called by ISRs */
alanffrench 0:52468b19aa21 149 P_SCB p_SCB = semaphore;
alanffrench 0:52468b19aa21 150
alanffrench 0:52468b19aa21 151 rt_psq_enq (p_SCB, 0);
alanffrench 0:52468b19aa21 152 rt_psh_req ();
alanffrench 0:52468b19aa21 153 }
alanffrench 0:52468b19aa21 154
alanffrench 0:52468b19aa21 155
alanffrench 0:52468b19aa21 156 /*--------------------------- rt_sem_psh ------------------------------------*/
alanffrench 0:52468b19aa21 157
alanffrench 0:52468b19aa21 158 void rt_sem_psh (P_SCB p_CB) {
alanffrench 0:52468b19aa21 159 /* Check if task has to be waken up */
alanffrench 0:52468b19aa21 160 P_TCB p_TCB;
alanffrench 0:52468b19aa21 161
alanffrench 0:52468b19aa21 162 if (p_CB->p_lnk != NULL) {
alanffrench 0:52468b19aa21 163 /* A task is waiting for token */
alanffrench 0:52468b19aa21 164 p_TCB = rt_get_first ((P_XCB)p_CB);
alanffrench 0:52468b19aa21 165 rt_rmv_dly (p_TCB);
alanffrench 0:52468b19aa21 166 p_TCB->state = READY;
alanffrench 0:52468b19aa21 167 #ifdef __CMSIS_RTOS
alanffrench 0:52468b19aa21 168 rt_ret_val(p_TCB, 1);
alanffrench 0:52468b19aa21 169 #else
alanffrench 0:52468b19aa21 170 rt_ret_val(p_TCB, OS_R_SEM);
alanffrench 0:52468b19aa21 171 #endif
alanffrench 0:52468b19aa21 172 rt_put_prio (&os_rdy, p_TCB);
alanffrench 0:52468b19aa21 173 }
alanffrench 0:52468b19aa21 174 else {
alanffrench 0:52468b19aa21 175 /* Store token */
alanffrench 0:52468b19aa21 176 p_CB->tokens++;
alanffrench 0:52468b19aa21 177 }
alanffrench 0:52468b19aa21 178 }
alanffrench 0:52468b19aa21 179
alanffrench 0:52468b19aa21 180 /*----------------------------------------------------------------------------
alanffrench 0:52468b19aa21 181 * end of file
alanffrench 0:52468b19aa21 182 *---------------------------------------------------------------------------*/
alanffrench 0:52468b19aa21 183