Knight KE / Mbed OS Game_Master

游戏王对战板，目前code还是空的

mbed-os/platform/mbed_critical.h@0:9b3d4731edbb, 2018-06-21 (annotated)

Committer:
WFKnight
Date:
Thu Jun 21 13:51:43 2018 +0000
Revision:
0:9b3d4731edbb
UART, RTOS, LED

Who changed what in which revision?

UserRevisionLine numberNew contents of line
WFKnight 0:9b3d4731edbb 1
WFKnight 0:9b3d4731edbb 2 /*
WFKnight 0:9b3d4731edbb 3 * Copyright (c) 2015-2016, ARM Limited, All Rights Reserved
WFKnight 0:9b3d4731edbb 4 * SPDX-License-Identifier: Apache-2.0
WFKnight 0:9b3d4731edbb 5 *
WFKnight 0:9b3d4731edbb 6 * Licensed under the Apache License, Version 2.0 (the "License"); you may
WFKnight 0:9b3d4731edbb 7 * not use this file except in compliance with the License.
WFKnight 0:9b3d4731edbb 8 * You may obtain a copy of the License at
WFKnight 0:9b3d4731edbb 9 *
WFKnight 0:9b3d4731edbb 10 * http://www.apache.org/licenses/LICENSE-2.0
WFKnight 0:9b3d4731edbb 11 *
WFKnight 0:9b3d4731edbb 12 * Unless required by applicable law or agreed to in writing, software
WFKnight 0:9b3d4731edbb 13 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
WFKnight 0:9b3d4731edbb 14 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
WFKnight 0:9b3d4731edbb 15 * See the License for the specific language governing permissions and
WFKnight 0:9b3d4731edbb 16 * limitations under the License.
WFKnight 0:9b3d4731edbb 17 */
WFKnight 0:9b3d4731edbb 18
WFKnight 0:9b3d4731edbb 19 #ifndef __MBED_UTIL_CRITICAL_H__
WFKnight 0:9b3d4731edbb 20 #define __MBED_UTIL_CRITICAL_H__
WFKnight 0:9b3d4731edbb 21
WFKnight 0:9b3d4731edbb 22 #include <stdbool.h>
WFKnight 0:9b3d4731edbb 23 #include <stdint.h>
WFKnight 0:9b3d4731edbb 24 #include <stddef.h>
WFKnight 0:9b3d4731edbb 25
WFKnight 0:9b3d4731edbb 26 #ifdef __cplusplus
WFKnight 0:9b3d4731edbb 27 extern "C" {
WFKnight 0:9b3d4731edbb 28 #endif
WFKnight 0:9b3d4731edbb 29
WFKnight 0:9b3d4731edbb 30 /** \addtogroup platform */
WFKnight 0:9b3d4731edbb 31 /** @{*/
WFKnight 0:9b3d4731edbb 32 /**
WFKnight 0:9b3d4731edbb 33 * \defgroup platform_critical critical section function
WFKnight 0:9b3d4731edbb 34 * @{
WFKnight 0:9b3d4731edbb 35 */
WFKnight 0:9b3d4731edbb 36
WFKnight 0:9b3d4731edbb 37 /** Determine the current interrupts enabled state
WFKnight 0:9b3d4731edbb 38 *
WFKnight 0:9b3d4731edbb 39 * This function can be called to determine whether or not interrupts are currently enabled.
WFKnight 0:9b3d4731edbb 40 * @note
WFKnight 0:9b3d4731edbb 41 * NOTE:
WFKnight 0:9b3d4731edbb 42 * This function works for both cortex-A and cortex-M, although the underlyng implementation
WFKnight 0:9b3d4731edbb 43 * differs.
WFKnight 0:9b3d4731edbb 44 * @return true if interrupts are enabled, false otherwise
WFKnight 0:9b3d4731edbb 45 */
WFKnight 0:9b3d4731edbb 46 bool core_util_are_interrupts_enabled(void);
WFKnight 0:9b3d4731edbb 47
WFKnight 0:9b3d4731edbb 48 /** Determine if this code is executing from an interrupt
WFKnight 0:9b3d4731edbb 49 *
WFKnight 0:9b3d4731edbb 50 * This function can be called to determine if the code is running on interrupt context.
WFKnight 0:9b3d4731edbb 51 * @note
WFKnight 0:9b3d4731edbb 52 * NOTE:
WFKnight 0:9b3d4731edbb 53 * This function works for both cortex-A and cortex-M, although the underlyng implementation
WFKnight 0:9b3d4731edbb 54 * differs.
WFKnight 0:9b3d4731edbb 55 * @return true if in an isr, false otherwise
WFKnight 0:9b3d4731edbb 56 */
WFKnight 0:9b3d4731edbb 57 bool core_util_is_isr_active(void);
WFKnight 0:9b3d4731edbb 58
WFKnight 0:9b3d4731edbb 59 /** Mark the start of a critical section
WFKnight 0:9b3d4731edbb 60 *
WFKnight 0:9b3d4731edbb 61 * This function should be called to mark the start of a critical section of code.
WFKnight 0:9b3d4731edbb 62 * @note
WFKnight 0:9b3d4731edbb 63 * NOTES:
WFKnight 0:9b3d4731edbb 64 * 1) The use of this style of critical section is targetted at C based implementations.
WFKnight 0:9b3d4731edbb 65 * 2) These critical sections can be nested.
WFKnight 0:9b3d4731edbb 66 * 3) The interrupt enable state on entry to the first critical section (of a nested set, or single
WFKnight 0:9b3d4731edbb 67 * section) will be preserved on exit from the section.
WFKnight 0:9b3d4731edbb 68 * 4) This implementation will currently only work on code running in privileged mode.
WFKnight 0:9b3d4731edbb 69 */
WFKnight 0:9b3d4731edbb 70 void core_util_critical_section_enter(void);
WFKnight 0:9b3d4731edbb 71
WFKnight 0:9b3d4731edbb 72 /** Mark the end of a critical section
WFKnight 0:9b3d4731edbb 73 *
WFKnight 0:9b3d4731edbb 74 * This function should be called to mark the end of a critical section of code.
WFKnight 0:9b3d4731edbb 75 * @note
WFKnight 0:9b3d4731edbb 76 * NOTES:
WFKnight 0:9b3d4731edbb 77 * 1) The use of this style of critical section is targetted at C based implementations.
WFKnight 0:9b3d4731edbb 78 * 2) These critical sections can be nested.
WFKnight 0:9b3d4731edbb 79 * 3) The interrupt enable state on entry to the first critical section (of a nested set, or single
WFKnight 0:9b3d4731edbb 80 * section) will be preserved on exit from the section.
WFKnight 0:9b3d4731edbb 81 * 4) This implementation will currently only work on code running in privileged mode.
WFKnight 0:9b3d4731edbb 82 */
WFKnight 0:9b3d4731edbb 83 void core_util_critical_section_exit(void);
WFKnight 0:9b3d4731edbb 84
WFKnight 0:9b3d4731edbb 85 /**
WFKnight 0:9b3d4731edbb 86 * Determine if we are currently in a critical section
WFKnight 0:9b3d4731edbb 87 *
WFKnight 0:9b3d4731edbb 88 * @return true if in a critical section, false otherwise.
WFKnight 0:9b3d4731edbb 89 */
WFKnight 0:9b3d4731edbb 90 bool core_util_in_critical_section(void);
WFKnight 0:9b3d4731edbb 91
WFKnight 0:9b3d4731edbb 92 /**
WFKnight 0:9b3d4731edbb 93 * Atomic compare and set. It compares the contents of a memory location to a
WFKnight 0:9b3d4731edbb 94 * given value and, only if they are the same, modifies the contents of that
WFKnight 0:9b3d4731edbb 95 * memory location to a given new value. This is done as a single atomic
WFKnight 0:9b3d4731edbb 96 * operation. The atomicity guarantees that the new value is calculated based on
WFKnight 0:9b3d4731edbb 97 * up-to-date information; if the value had been updated by another thread in
WFKnight 0:9b3d4731edbb 98 * the meantime, the write would fail due to a mismatched expectedCurrentValue.
WFKnight 0:9b3d4731edbb 99 *
WFKnight 0:9b3d4731edbb 100 * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect
WFKnight 0:9b3d4731edbb 101 * you to the article on compare-and swap].
WFKnight 0:9b3d4731edbb 102 *
WFKnight 0:9b3d4731edbb 103 * @param ptr The target memory location.
WFKnight 0:9b3d4731edbb 104 * @param[in,out] expectedCurrentValue A pointer to some location holding the
WFKnight 0:9b3d4731edbb 105 * expected current value of the data being set atomically.
WFKnight 0:9b3d4731edbb 106 * The computed 'desiredValue' should be a function of this current value.
WFKnight 0:9b3d4731edbb 107 * @note: This is an in-out parameter. In the
WFKnight 0:9b3d4731edbb 108 * failure case of atomic_cas (where the
WFKnight 0:9b3d4731edbb 109 * destination isn't set), the pointee of expectedCurrentValue is
WFKnight 0:9b3d4731edbb 110 * updated with the current value.
WFKnight 0:9b3d4731edbb 111 * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'.
WFKnight 0:9b3d4731edbb 112 *
WFKnight 0:9b3d4731edbb 113 * @return true if the memory location was atomically
WFKnight 0:9b3d4731edbb 114 * updated with the desired value (after verifying
WFKnight 0:9b3d4731edbb 115 * that it contained the expectedCurrentValue),
WFKnight 0:9b3d4731edbb 116 * false otherwise. In the failure case,
WFKnight 0:9b3d4731edbb 117 * exepctedCurrentValue is updated with the new
WFKnight 0:9b3d4731edbb 118 * value of the target memory location.
WFKnight 0:9b3d4731edbb 119 *
WFKnight 0:9b3d4731edbb 120 * pseudocode:
WFKnight 0:9b3d4731edbb 121 * function cas(p : pointer to int, old : pointer to int, new : int) returns bool {
WFKnight 0:9b3d4731edbb 122 * if *p != *old {
WFKnight 0:9b3d4731edbb 123 * *old = *p
WFKnight 0:9b3d4731edbb 124 * return false
WFKnight 0:9b3d4731edbb 125 * }
WFKnight 0:9b3d4731edbb 126 * *p = new
WFKnight 0:9b3d4731edbb 127 * return true
WFKnight 0:9b3d4731edbb 128 * }
WFKnight 0:9b3d4731edbb 129 *
WFKnight 0:9b3d4731edbb 130 * @note: In the failure case (where the destination isn't set), the value
WFKnight 0:9b3d4731edbb 131 * pointed to by expectedCurrentValue is instead updated with the current value.
WFKnight 0:9b3d4731edbb 132 * This property helps writing concise code for the following incr:
WFKnight 0:9b3d4731edbb 133 *
WFKnight 0:9b3d4731edbb 134 * function incr(p : pointer to int, a : int) returns int {
WFKnight 0:9b3d4731edbb 135 * done = false
WFKnight 0:9b3d4731edbb 136 * value = *p // This fetch operation need not be atomic.
WFKnight 0:9b3d4731edbb 137 * while not done {
WFKnight 0:9b3d4731edbb 138 * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success
WFKnight 0:9b3d4731edbb 139 * }
WFKnight 0:9b3d4731edbb 140 * return value + a
WFKnight 0:9b3d4731edbb 141 * }
WFKnight 0:9b3d4731edbb 142 *
WFKnight 0:9b3d4731edbb 143 * @note: This corresponds to the C11 "atomic_compare_exchange_strong" - it
WFKnight 0:9b3d4731edbb 144 * always succeeds if the current value is expected, as per the pseudocode
WFKnight 0:9b3d4731edbb 145 * above; it will not spuriously fail as "atomic_compare_exchange_weak" may.
WFKnight 0:9b3d4731edbb 146 */
WFKnight 0:9b3d4731edbb 147 bool core_util_atomic_cas_u8(volatile uint8_t *ptr, uint8_t *expectedCurrentValue, uint8_t desiredValue);
WFKnight 0:9b3d4731edbb 148
WFKnight 0:9b3d4731edbb 149 /**
WFKnight 0:9b3d4731edbb 150 * Atomic compare and set. It compares the contents of a memory location to a
WFKnight 0:9b3d4731edbb 151 * given value and, only if they are the same, modifies the contents of that
WFKnight 0:9b3d4731edbb 152 * memory location to a given new value. This is done as a single atomic
WFKnight 0:9b3d4731edbb 153 * operation. The atomicity guarantees that the new value is calculated based on
WFKnight 0:9b3d4731edbb 154 * up-to-date information; if the value had been updated by another thread in
WFKnight 0:9b3d4731edbb 155 * the meantime, the write would fail due to a mismatched expectedCurrentValue.
WFKnight 0:9b3d4731edbb 156 *
WFKnight 0:9b3d4731edbb 157 * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect
WFKnight 0:9b3d4731edbb 158 * you to the article on compare-and swap].
WFKnight 0:9b3d4731edbb 159 *
WFKnight 0:9b3d4731edbb 160 * @param ptr The target memory location.
WFKnight 0:9b3d4731edbb 161 * @param[in,out] expectedCurrentValue A pointer to some location holding the
WFKnight 0:9b3d4731edbb 162 * expected current value of the data being set atomically.
WFKnight 0:9b3d4731edbb 163 * The computed 'desiredValue' should be a function of this current value.
WFKnight 0:9b3d4731edbb 164 * @note: This is an in-out parameter. In the
WFKnight 0:9b3d4731edbb 165 * failure case of atomic_cas (where the
WFKnight 0:9b3d4731edbb 166 * destination isn't set), the pointee of expectedCurrentValue is
WFKnight 0:9b3d4731edbb 167 * updated with the current value.
WFKnight 0:9b3d4731edbb 168 * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'.
WFKnight 0:9b3d4731edbb 169 *
WFKnight 0:9b3d4731edbb 170 * @return true if the memory location was atomically
WFKnight 0:9b3d4731edbb 171 * updated with the desired value (after verifying
WFKnight 0:9b3d4731edbb 172 * that it contained the expectedCurrentValue),
WFKnight 0:9b3d4731edbb 173 * false otherwise. In the failure case,
WFKnight 0:9b3d4731edbb 174 * exepctedCurrentValue is updated with the new
WFKnight 0:9b3d4731edbb 175 * value of the target memory location.
WFKnight 0:9b3d4731edbb 176 *
WFKnight 0:9b3d4731edbb 177 * pseudocode:
WFKnight 0:9b3d4731edbb 178 * function cas(p : pointer to int, old : pointer to int, new : int) returns bool {
WFKnight 0:9b3d4731edbb 179 * if *p != *old {
WFKnight 0:9b3d4731edbb 180 * *old = *p
WFKnight 0:9b3d4731edbb 181 * return false
WFKnight 0:9b3d4731edbb 182 * }
WFKnight 0:9b3d4731edbb 183 * *p = new
WFKnight 0:9b3d4731edbb 184 * return true
WFKnight 0:9b3d4731edbb 185 * }
WFKnight 0:9b3d4731edbb 186 *
WFKnight 0:9b3d4731edbb 187 * @note: In the failure case (where the destination isn't set), the value
WFKnight 0:9b3d4731edbb 188 * pointed to by expectedCurrentValue is instead updated with the current value.
WFKnight 0:9b3d4731edbb 189 * This property helps writing concise code for the following incr:
WFKnight 0:9b3d4731edbb 190 *
WFKnight 0:9b3d4731edbb 191 * function incr(p : pointer to int, a : int) returns int {
WFKnight 0:9b3d4731edbb 192 * done = false
WFKnight 0:9b3d4731edbb 193 * value = *p // This fetch operation need not be atomic.
WFKnight 0:9b3d4731edbb 194 * while not done {
WFKnight 0:9b3d4731edbb 195 * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success
WFKnight 0:9b3d4731edbb 196 * }
WFKnight 0:9b3d4731edbb 197 * return value + a
WFKnight 0:9b3d4731edbb 198 * }
WFKnight 0:9b3d4731edbb 199 *
WFKnight 0:9b3d4731edbb 200 * @note: This corresponds to the C11 "atomic_compare_exchange_strong" - it
WFKnight 0:9b3d4731edbb 201 * always succeeds if the current value is expected, as per the pseudocode
WFKnight 0:9b3d4731edbb 202 * above; it will not spuriously fail as "atomic_compare_exchange_weak" may.
WFKnight 0:9b3d4731edbb 203 */
WFKnight 0:9b3d4731edbb 204 bool core_util_atomic_cas_u16(volatile uint16_t *ptr, uint16_t *expectedCurrentValue, uint16_t desiredValue);
WFKnight 0:9b3d4731edbb 205
WFKnight 0:9b3d4731edbb 206 /**
WFKnight 0:9b3d4731edbb 207 * Atomic compare and set. It compares the contents of a memory location to a
WFKnight 0:9b3d4731edbb 208 * given value and, only if they are the same, modifies the contents of that
WFKnight 0:9b3d4731edbb 209 * memory location to a given new value. This is done as a single atomic
WFKnight 0:9b3d4731edbb 210 * operation. The atomicity guarantees that the new value is calculated based on
WFKnight 0:9b3d4731edbb 211 * up-to-date information; if the value had been updated by another thread in
WFKnight 0:9b3d4731edbb 212 * the meantime, the write would fail due to a mismatched expectedCurrentValue.
WFKnight 0:9b3d4731edbb 213 *
WFKnight 0:9b3d4731edbb 214 * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect
WFKnight 0:9b3d4731edbb 215 * you to the article on compare-and swap].
WFKnight 0:9b3d4731edbb 216 *
WFKnight 0:9b3d4731edbb 217 * @param ptr The target memory location.
WFKnight 0:9b3d4731edbb 218 * @param[in,out] expectedCurrentValue A pointer to some location holding the
WFKnight 0:9b3d4731edbb 219 * expected current value of the data being set atomically.
WFKnight 0:9b3d4731edbb 220 * The computed 'desiredValue' should be a function of this current value.
WFKnight 0:9b3d4731edbb 221 * @note: This is an in-out parameter. In the
WFKnight 0:9b3d4731edbb 222 * failure case of atomic_cas (where the
WFKnight 0:9b3d4731edbb 223 * destination isn't set), the pointee of expectedCurrentValue is
WFKnight 0:9b3d4731edbb 224 * updated with the current value.
WFKnight 0:9b3d4731edbb 225 * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'.
WFKnight 0:9b3d4731edbb 226 *
WFKnight 0:9b3d4731edbb 227 * @return true if the memory location was atomically
WFKnight 0:9b3d4731edbb 228 * updated with the desired value (after verifying
WFKnight 0:9b3d4731edbb 229 * that it contained the expectedCurrentValue),
WFKnight 0:9b3d4731edbb 230 * false otherwise. In the failure case,
WFKnight 0:9b3d4731edbb 231 * exepctedCurrentValue is updated with the new
WFKnight 0:9b3d4731edbb 232 * value of the target memory location.
WFKnight 0:9b3d4731edbb 233 *
WFKnight 0:9b3d4731edbb 234 * pseudocode:
WFKnight 0:9b3d4731edbb 235 * function cas(p : pointer to int, old : pointer to int, new : int) returns bool {
WFKnight 0:9b3d4731edbb 236 * if *p != *old {
WFKnight 0:9b3d4731edbb 237 * *old = *p
WFKnight 0:9b3d4731edbb 238 * return false
WFKnight 0:9b3d4731edbb 239 * }
WFKnight 0:9b3d4731edbb 240 * *p = new
WFKnight 0:9b3d4731edbb 241 * return true
WFKnight 0:9b3d4731edbb 242 * }
WFKnight 0:9b3d4731edbb 243 *
WFKnight 0:9b3d4731edbb 244 * @note: In the failure case (where the destination isn't set), the value
WFKnight 0:9b3d4731edbb 245 * pointed to by expectedCurrentValue is instead updated with the current value.
WFKnight 0:9b3d4731edbb 246 * This property helps writing concise code for the following incr:
WFKnight 0:9b3d4731edbb 247 *
WFKnight 0:9b3d4731edbb 248 * function incr(p : pointer to int, a : int) returns int {
WFKnight 0:9b3d4731edbb 249 * done = false
WFKnight 0:9b3d4731edbb 250 * value = *p // This fetch operation need not be atomic.
WFKnight 0:9b3d4731edbb 251 * while not done {
WFKnight 0:9b3d4731edbb 252 * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success
WFKnight 0:9b3d4731edbb 253 * }
WFKnight 0:9b3d4731edbb 254 * return value + a
WFKnight 0:9b3d4731edbb 255 *
WFKnight 0:9b3d4731edbb 256 * @note: This corresponds to the C11 "atomic_compare_exchange_strong" - it
WFKnight 0:9b3d4731edbb 257 * always succeeds if the current value is expected, as per the pseudocode
WFKnight 0:9b3d4731edbb 258 * above; it will not spuriously fail as "atomic_compare_exchange_weak" may.
WFKnight 0:9b3d4731edbb 259 * }
WFKnight 0:9b3d4731edbb 260 */
WFKnight 0:9b3d4731edbb 261 bool core_util_atomic_cas_u32(volatile uint32_t *ptr, uint32_t *expectedCurrentValue, uint32_t desiredValue);
WFKnight 0:9b3d4731edbb 262
WFKnight 0:9b3d4731edbb 263 /**
WFKnight 0:9b3d4731edbb 264 * Atomic compare and set. It compares the contents of a memory location to a
WFKnight 0:9b3d4731edbb 265 * given value and, only if they are the same, modifies the contents of that
WFKnight 0:9b3d4731edbb 266 * memory location to a given new value. This is done as a single atomic
WFKnight 0:9b3d4731edbb 267 * operation. The atomicity guarantees that the new value is calculated based on
WFKnight 0:9b3d4731edbb 268 * up-to-date information; if the value had been updated by another thread in
WFKnight 0:9b3d4731edbb 269 * the meantime, the write would fail due to a mismatched expectedCurrentValue.
WFKnight 0:9b3d4731edbb 270 *
WFKnight 0:9b3d4731edbb 271 * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect
WFKnight 0:9b3d4731edbb 272 * you to the article on compare-and swap].
WFKnight 0:9b3d4731edbb 273 *
WFKnight 0:9b3d4731edbb 274 * @param ptr The target memory location.
WFKnight 0:9b3d4731edbb 275 * @param[in,out] expectedCurrentValue A pointer to some location holding the
WFKnight 0:9b3d4731edbb 276 * expected current value of the data being set atomically.
WFKnight 0:9b3d4731edbb 277 * The computed 'desiredValue' should be a function of this current value.
WFKnight 0:9b3d4731edbb 278 * @note: This is an in-out parameter. In the
WFKnight 0:9b3d4731edbb 279 * failure case of atomic_cas (where the
WFKnight 0:9b3d4731edbb 280 * destination isn't set), the pointee of expectedCurrentValue is
WFKnight 0:9b3d4731edbb 281 * updated with the current value.
WFKnight 0:9b3d4731edbb 282 * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'.
WFKnight 0:9b3d4731edbb 283 *
WFKnight 0:9b3d4731edbb 284 * @return true if the memory location was atomically
WFKnight 0:9b3d4731edbb 285 * updated with the desired value (after verifying
WFKnight 0:9b3d4731edbb 286 * that it contained the expectedCurrentValue),
WFKnight 0:9b3d4731edbb 287 * false otherwise. In the failure case,
WFKnight 0:9b3d4731edbb 288 * exepctedCurrentValue is updated with the new
WFKnight 0:9b3d4731edbb 289 * value of the target memory location.
WFKnight 0:9b3d4731edbb 290 *
WFKnight 0:9b3d4731edbb 291 * pseudocode:
WFKnight 0:9b3d4731edbb 292 * function cas(p : pointer to int, old : pointer to int, new : int) returns bool {
WFKnight 0:9b3d4731edbb 293 * if *p != *old {
WFKnight 0:9b3d4731edbb 294 * *old = *p
WFKnight 0:9b3d4731edbb 295 * return false
WFKnight 0:9b3d4731edbb 296 * }
WFKnight 0:9b3d4731edbb 297 * *p = new
WFKnight 0:9b3d4731edbb 298 * return true
WFKnight 0:9b3d4731edbb 299 * }
WFKnight 0:9b3d4731edbb 300 *
WFKnight 0:9b3d4731edbb 301 * @note: In the failure case (where the destination isn't set), the value
WFKnight 0:9b3d4731edbb 302 * pointed to by expectedCurrentValue is instead updated with the current value.
WFKnight 0:9b3d4731edbb 303 * This property helps writing concise code for the following incr:
WFKnight 0:9b3d4731edbb 304 *
WFKnight 0:9b3d4731edbb 305 * function incr(p : pointer to int, a : int) returns int {
WFKnight 0:9b3d4731edbb 306 * done = false
WFKnight 0:9b3d4731edbb 307 * value = *p // This fetch operation need not be atomic.
WFKnight 0:9b3d4731edbb 308 * while not done {
WFKnight 0:9b3d4731edbb 309 * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success
WFKnight 0:9b3d4731edbb 310 * }
WFKnight 0:9b3d4731edbb 311 * return value + a
WFKnight 0:9b3d4731edbb 312 * }
WFKnight 0:9b3d4731edbb 313 *
WFKnight 0:9b3d4731edbb 314 * @note: This corresponds to the C11 "atomic_compare_exchange_strong" - it
WFKnight 0:9b3d4731edbb 315 * always succeeds if the current value is expected, as per the pseudocode
WFKnight 0:9b3d4731edbb 316 * above; it will not spuriously fail as "atomic_compare_exchange_weak" may.
WFKnight 0:9b3d4731edbb 317 */
WFKnight 0:9b3d4731edbb 318 bool core_util_atomic_cas_ptr(void * volatile *ptr, void **expectedCurrentValue, void *desiredValue);
WFKnight 0:9b3d4731edbb 319
WFKnight 0:9b3d4731edbb 320 /**
WFKnight 0:9b3d4731edbb 321 * Atomic increment.
WFKnight 0:9b3d4731edbb 322 * @param valuePtr Target memory location being incremented.
WFKnight 0:9b3d4731edbb 323 * @param delta The amount being incremented.
WFKnight 0:9b3d4731edbb 324 * @return The new incremented value.
WFKnight 0:9b3d4731edbb 325 */
WFKnight 0:9b3d4731edbb 326 uint8_t core_util_atomic_incr_u8(volatile uint8_t *valuePtr, uint8_t delta);
WFKnight 0:9b3d4731edbb 327
WFKnight 0:9b3d4731edbb 328 /**
WFKnight 0:9b3d4731edbb 329 * Atomic increment.
WFKnight 0:9b3d4731edbb 330 * @param valuePtr Target memory location being incremented.
WFKnight 0:9b3d4731edbb 331 * @param delta The amount being incremented.
WFKnight 0:9b3d4731edbb 332 * @return The new incremented value.
WFKnight 0:9b3d4731edbb 333 */
WFKnight 0:9b3d4731edbb 334 uint16_t core_util_atomic_incr_u16(volatile uint16_t *valuePtr, uint16_t delta);
WFKnight 0:9b3d4731edbb 335
WFKnight 0:9b3d4731edbb 336 /**
WFKnight 0:9b3d4731edbb 337 * Atomic increment.
WFKnight 0:9b3d4731edbb 338 * @param valuePtr Target memory location being incremented.
WFKnight 0:9b3d4731edbb 339 * @param delta The amount being incremented.
WFKnight 0:9b3d4731edbb 340 * @return The new incremented value.
WFKnight 0:9b3d4731edbb 341 */
WFKnight 0:9b3d4731edbb 342 uint32_t core_util_atomic_incr_u32(volatile uint32_t *valuePtr, uint32_t delta);
WFKnight 0:9b3d4731edbb 343
WFKnight 0:9b3d4731edbb 344 /**
WFKnight 0:9b3d4731edbb 345 * Atomic increment.
WFKnight 0:9b3d4731edbb 346 * @param valuePtr Target memory location being incremented.
WFKnight 0:9b3d4731edbb 347 * @param delta The amount being incremented in bytes.
WFKnight 0:9b3d4731edbb 348 * @return The new incremented value.
WFKnight 0:9b3d4731edbb 349 *
WFKnight 0:9b3d4731edbb 350 * @note The type of the pointer argument is not taken into account
WFKnight 0:9b3d4731edbb 351 * and the pointer is incremented by bytes.
WFKnight 0:9b3d4731edbb 352 */
WFKnight 0:9b3d4731edbb 353 void *core_util_atomic_incr_ptr(void * volatile *valuePtr, ptrdiff_t delta);
WFKnight 0:9b3d4731edbb 354
WFKnight 0:9b3d4731edbb 355 /**
WFKnight 0:9b3d4731edbb 356 * Atomic decrement.
WFKnight 0:9b3d4731edbb 357 * @param valuePtr Target memory location being decremented.
WFKnight 0:9b3d4731edbb 358 * @param delta The amount being decremented.
WFKnight 0:9b3d4731edbb 359 * @return The new decremented value.
WFKnight 0:9b3d4731edbb 360 */
WFKnight 0:9b3d4731edbb 361 uint8_t core_util_atomic_decr_u8(volatile uint8_t *valuePtr, uint8_t delta);
WFKnight 0:9b3d4731edbb 362
WFKnight 0:9b3d4731edbb 363 /**
WFKnight 0:9b3d4731edbb 364 * Atomic decrement.
WFKnight 0:9b3d4731edbb 365 * @param valuePtr Target memory location being decremented.
WFKnight 0:9b3d4731edbb 366 * @param delta The amount being decremented.
WFKnight 0:9b3d4731edbb 367 * @return The new decremented value.
WFKnight 0:9b3d4731edbb 368 */
WFKnight 0:9b3d4731edbb 369 uint16_t core_util_atomic_decr_u16(volatile uint16_t *valuePtr, uint16_t delta);
WFKnight 0:9b3d4731edbb 370
WFKnight 0:9b3d4731edbb 371 /**
WFKnight 0:9b3d4731edbb 372 * Atomic decrement.
WFKnight 0:9b3d4731edbb 373 * @param valuePtr Target memory location being decremented.
WFKnight 0:9b3d4731edbb 374 * @param delta The amount being decremented.
WFKnight 0:9b3d4731edbb 375 * @return The new decremented value.
WFKnight 0:9b3d4731edbb 376 */
WFKnight 0:9b3d4731edbb 377 uint32_t core_util_atomic_decr_u32(volatile uint32_t *valuePtr, uint32_t delta);
WFKnight 0:9b3d4731edbb 378
WFKnight 0:9b3d4731edbb 379 /**
WFKnight 0:9b3d4731edbb 380 * Atomic decrement.
WFKnight 0:9b3d4731edbb 381 * @param valuePtr Target memory location being decremented.
WFKnight 0:9b3d4731edbb 382 * @param delta The amount being decremented in bytes.
WFKnight 0:9b3d4731edbb 383 * @return The new decremented value.
WFKnight 0:9b3d4731edbb 384 *
WFKnight 0:9b3d4731edbb 385 * @note The type of the pointer argument is not taken into account
WFKnight 0:9b3d4731edbb 386 * and the pointer is decremented by bytes
WFKnight 0:9b3d4731edbb 387 */
WFKnight 0:9b3d4731edbb 388 void *core_util_atomic_decr_ptr(void * volatile *valuePtr, ptrdiff_t delta);
WFKnight 0:9b3d4731edbb 389
WFKnight 0:9b3d4731edbb 390 #ifdef __cplusplus
WFKnight 0:9b3d4731edbb 391 } // extern "C"
WFKnight 0:9b3d4731edbb 392 #endif
WFKnight 0:9b3d4731edbb 393 /**@}*/
WFKnight 0:9b3d4731edbb 394
WFKnight 0:9b3d4731edbb 395 /**@}*/
WFKnight 0:9b3d4731edbb 396
WFKnight 0:9b3d4731edbb 397 #endif // __MBED_UTIL_CRITICAL_H__
WFKnight 0:9b3d4731edbb 398
WFKnight 0:9b3d4731edbb 399
WFKnight 0:9b3d4731edbb 400