Umar Naeem / mbed-dev

mbed library sources. Supersedes mbed-src.

Fork of mbed-dev by Umar Naeem

platform/mbed_critical.h@160:d5399cc887bb, 2017-03-14 (annotated)

Committer:
<>
Date:
Tue Mar 14 16:40:56 2017 +0000
Revision:
160:d5399cc887bb
This updates the lib to the mbed lib v138

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 160:d5399cc887bb 1
<> 160:d5399cc887bb 2 /** \addtogroup platform */
<> 160:d5399cc887bb 3 /** @{*/
<> 160:d5399cc887bb 4 /*
<> 160:d5399cc887bb 5 * Copyright (c) 2015-2016, ARM Limited, All Rights Reserved
<> 160:d5399cc887bb 6 * SPDX-License-Identifier: Apache-2.0
<> 160:d5399cc887bb 7 *
<> 160:d5399cc887bb 8 * Licensed under the Apache License, Version 2.0 (the "License"); you may
<> 160:d5399cc887bb 9 * not use this file except in compliance with the License.
<> 160:d5399cc887bb 10 * You may obtain a copy of the License at
<> 160:d5399cc887bb 11 *
<> 160:d5399cc887bb 12 * http://www.apache.org/licenses/LICENSE-2.0
<> 160:d5399cc887bb 13 *
<> 160:d5399cc887bb 14 * Unless required by applicable law or agreed to in writing, software
<> 160:d5399cc887bb 15 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
<> 160:d5399cc887bb 16 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 160:d5399cc887bb 17 * See the License for the specific language governing permissions and
<> 160:d5399cc887bb 18 * limitations under the License.
<> 160:d5399cc887bb 19 */
<> 160:d5399cc887bb 20
<> 160:d5399cc887bb 21 #ifndef __MBED_UTIL_CRITICAL_H__
<> 160:d5399cc887bb 22 #define __MBED_UTIL_CRITICAL_H__
<> 160:d5399cc887bb 23
<> 160:d5399cc887bb 24 #include <stdbool.h>
<> 160:d5399cc887bb 25 #include <stdint.h>
<> 160:d5399cc887bb 26 #include <stddef.h>
<> 160:d5399cc887bb 27
<> 160:d5399cc887bb 28 #ifdef __cplusplus
<> 160:d5399cc887bb 29 extern "C" {
<> 160:d5399cc887bb 30 #endif
<> 160:d5399cc887bb 31
<> 160:d5399cc887bb 32
<> 160:d5399cc887bb 33 /** Determine the current interrupts enabled state
<> 160:d5399cc887bb 34 *
<> 160:d5399cc887bb 35 * This function can be called to determine whether or not interrupts are currently enabled.
<> 160:d5399cc887bb 36 * \note
<> 160:d5399cc887bb 37 * NOTE:
<> 160:d5399cc887bb 38 * This function works for both cortex-A and cortex-M, although the underlyng implementation
<> 160:d5399cc887bb 39 * differs.
<> 160:d5399cc887bb 40 * @return true if interrupts are enabled, false otherwise
<> 160:d5399cc887bb 41 */
<> 160:d5399cc887bb 42 bool core_util_are_interrupts_enabled(void);
<> 160:d5399cc887bb 43
<> 160:d5399cc887bb 44 /** Mark the start of a critical section
<> 160:d5399cc887bb 45 *
<> 160:d5399cc887bb 46 * This function should be called to mark the start of a critical section of code.
<> 160:d5399cc887bb 47 * \note
<> 160:d5399cc887bb 48 * NOTES:
<> 160:d5399cc887bb 49 * 1) The use of this style of critical section is targetted at C based implementations.
<> 160:d5399cc887bb 50 * 2) These critical sections can be nested.
<> 160:d5399cc887bb 51 * 3) The interrupt enable state on entry to the first critical section (of a nested set, or single
<> 160:d5399cc887bb 52 * section) will be preserved on exit from the section.
<> 160:d5399cc887bb 53 * 4) This implementation will currently only work on code running in privileged mode.
<> 160:d5399cc887bb 54 */
<> 160:d5399cc887bb 55 void core_util_critical_section_enter(void);
<> 160:d5399cc887bb 56
<> 160:d5399cc887bb 57 /** Mark the end of a critical section
<> 160:d5399cc887bb 58 *
<> 160:d5399cc887bb 59 * This function should be called to mark the end of a critical section of code.
<> 160:d5399cc887bb 60 * \note
<> 160:d5399cc887bb 61 * NOTES:
<> 160:d5399cc887bb 62 * 1) The use of this style of critical section is targetted at C based implementations.
<> 160:d5399cc887bb 63 * 2) These critical sections can be nested.
<> 160:d5399cc887bb 64 * 3) The interrupt enable state on entry to the first critical section (of a nested set, or single
<> 160:d5399cc887bb 65 * section) will be preserved on exit from the section.
<> 160:d5399cc887bb 66 * 4) This implementation will currently only work on code running in privileged mode.
<> 160:d5399cc887bb 67 */
<> 160:d5399cc887bb 68 void core_util_critical_section_exit(void);
<> 160:d5399cc887bb 69
<> 160:d5399cc887bb 70 /**
<> 160:d5399cc887bb 71 * Atomic compare and set. It compares the contents of a memory location to a
<> 160:d5399cc887bb 72 * given value and, only if they are the same, modifies the contents of that
<> 160:d5399cc887bb 73 * memory location to a given new value. This is done as a single atomic
<> 160:d5399cc887bb 74 * operation. The atomicity guarantees that the new value is calculated based on
<> 160:d5399cc887bb 75 * up-to-date information; if the value had been updated by another thread in
<> 160:d5399cc887bb 76 * the meantime, the write would fail due to a mismatched expectedCurrentValue.
<> 160:d5399cc887bb 77 *
<> 160:d5399cc887bb 78 * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect
<> 160:d5399cc887bb 79 * you to the article on compare-and swap].
<> 160:d5399cc887bb 80 *
<> 160:d5399cc887bb 81 * @param ptr The target memory location.
<> 160:d5399cc887bb 82 * @param[in,out] expectedCurrentValue A pointer to some location holding the
<> 160:d5399cc887bb 83 * expected current value of the data being set atomically.
<> 160:d5399cc887bb 84 * The computed 'desiredValue' should be a function of this current value.
<> 160:d5399cc887bb 85 * @Note: This is an in-out parameter. In the
<> 160:d5399cc887bb 86 * failure case of atomic_cas (where the
<> 160:d5399cc887bb 87 * destination isn't set), the pointee of expectedCurrentValue is
<> 160:d5399cc887bb 88 * updated with the current value.
<> 160:d5399cc887bb 89 * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'.
<> 160:d5399cc887bb 90 *
<> 160:d5399cc887bb 91 * @return true if the memory location was atomically
<> 160:d5399cc887bb 92 * updated with the desired value (after verifying
<> 160:d5399cc887bb 93 * that it contained the expectedCurrentValue),
<> 160:d5399cc887bb 94 * false otherwise. In the failure case,
<> 160:d5399cc887bb 95 * exepctedCurrentValue is updated with the new
<> 160:d5399cc887bb 96 * value of the target memory location.
<> 160:d5399cc887bb 97 *
<> 160:d5399cc887bb 98 * pseudocode:
<> 160:d5399cc887bb 99 * function cas(p : pointer to int, old : pointer to int, new : int) returns bool {
<> 160:d5399cc887bb 100 * if *p != *old {
<> 160:d5399cc887bb 101 * *old = *p
<> 160:d5399cc887bb 102 * return false
<> 160:d5399cc887bb 103 * }
<> 160:d5399cc887bb 104 * *p = new
<> 160:d5399cc887bb 105 * return true
<> 160:d5399cc887bb 106 * }
<> 160:d5399cc887bb 107 *
<> 160:d5399cc887bb 108 * @Note: In the failure case (where the destination isn't set), the value
<> 160:d5399cc887bb 109 * pointed to by expectedCurrentValue is still updated with the current value.
<> 160:d5399cc887bb 110 * This property helps writing concise code for the following incr:
<> 160:d5399cc887bb 111 *
<> 160:d5399cc887bb 112 * function incr(p : pointer to int, a : int) returns int {
<> 160:d5399cc887bb 113 * done = false
<> 160:d5399cc887bb 114 * value = *p // This fetch operation need not be atomic.
<> 160:d5399cc887bb 115 * while not done {
<> 160:d5399cc887bb 116 * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success
<> 160:d5399cc887bb 117 * }
<> 160:d5399cc887bb 118 * return value + a
<> 160:d5399cc887bb 119 * }
<> 160:d5399cc887bb 120 */
<> 160:d5399cc887bb 121 bool core_util_atomic_cas_u8(uint8_t *ptr, uint8_t *expectedCurrentValue, uint8_t desiredValue);
<> 160:d5399cc887bb 122
<> 160:d5399cc887bb 123 /**
<> 160:d5399cc887bb 124 * Atomic compare and set. It compares the contents of a memory location to a
<> 160:d5399cc887bb 125 * given value and, only if they are the same, modifies the contents of that
<> 160:d5399cc887bb 126 * memory location to a given new value. This is done as a single atomic
<> 160:d5399cc887bb 127 * operation. The atomicity guarantees that the new value is calculated based on
<> 160:d5399cc887bb 128 * up-to-date information; if the value had been updated by another thread in
<> 160:d5399cc887bb 129 * the meantime, the write would fail due to a mismatched expectedCurrentValue.
<> 160:d5399cc887bb 130 *
<> 160:d5399cc887bb 131 * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect
<> 160:d5399cc887bb 132 * you to the article on compare-and swap].
<> 160:d5399cc887bb 133 *
<> 160:d5399cc887bb 134 * @param ptr The target memory location.
<> 160:d5399cc887bb 135 * @param[in,out] expectedCurrentValue A pointer to some location holding the
<> 160:d5399cc887bb 136 * expected current value of the data being set atomically.
<> 160:d5399cc887bb 137 * The computed 'desiredValue' should be a function of this current value.
<> 160:d5399cc887bb 138 * @Note: This is an in-out parameter. In the
<> 160:d5399cc887bb 139 * failure case of atomic_cas (where the
<> 160:d5399cc887bb 140 * destination isn't set), the pointee of expectedCurrentValue is
<> 160:d5399cc887bb 141 * updated with the current value.
<> 160:d5399cc887bb 142 * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'.
<> 160:d5399cc887bb 143 *
<> 160:d5399cc887bb 144 * @return true if the memory location was atomically
<> 160:d5399cc887bb 145 * updated with the desired value (after verifying
<> 160:d5399cc887bb 146 * that it contained the expectedCurrentValue),
<> 160:d5399cc887bb 147 * false otherwise. In the failure case,
<> 160:d5399cc887bb 148 * exepctedCurrentValue is updated with the new
<> 160:d5399cc887bb 149 * value of the target memory location.
<> 160:d5399cc887bb 150 *
<> 160:d5399cc887bb 151 * pseudocode:
<> 160:d5399cc887bb 152 * function cas(p : pointer to int, old : pointer to int, new : int) returns bool {
<> 160:d5399cc887bb 153 * if *p != *old {
<> 160:d5399cc887bb 154 * *old = *p
<> 160:d5399cc887bb 155 * return false
<> 160:d5399cc887bb 156 * }
<> 160:d5399cc887bb 157 * *p = new
<> 160:d5399cc887bb 158 * return true
<> 160:d5399cc887bb 159 * }
<> 160:d5399cc887bb 160 *
<> 160:d5399cc887bb 161 * @Note: In the failure case (where the destination isn't set), the value
<> 160:d5399cc887bb 162 * pointed to by expectedCurrentValue is still updated with the current value.
<> 160:d5399cc887bb 163 * This property helps writing concise code for the following incr:
<> 160:d5399cc887bb 164 *
<> 160:d5399cc887bb 165 * function incr(p : pointer to int, a : int) returns int {
<> 160:d5399cc887bb 166 * done = false
<> 160:d5399cc887bb 167 * value = *p // This fetch operation need not be atomic.
<> 160:d5399cc887bb 168 * while not done {
<> 160:d5399cc887bb 169 * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success
<> 160:d5399cc887bb 170 * }
<> 160:d5399cc887bb 171 * return value + a
<> 160:d5399cc887bb 172 * }
<> 160:d5399cc887bb 173 */
<> 160:d5399cc887bb 174 bool core_util_atomic_cas_u16(uint16_t *ptr, uint16_t *expectedCurrentValue, uint16_t desiredValue);
<> 160:d5399cc887bb 175
<> 160:d5399cc887bb 176 /**
<> 160:d5399cc887bb 177 * Atomic compare and set. It compares the contents of a memory location to a
<> 160:d5399cc887bb 178 * given value and, only if they are the same, modifies the contents of that
<> 160:d5399cc887bb 179 * memory location to a given new value. This is done as a single atomic
<> 160:d5399cc887bb 180 * operation. The atomicity guarantees that the new value is calculated based on
<> 160:d5399cc887bb 181 * up-to-date information; if the value had been updated by another thread in
<> 160:d5399cc887bb 182 * the meantime, the write would fail due to a mismatched expectedCurrentValue.
<> 160:d5399cc887bb 183 *
<> 160:d5399cc887bb 184 * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect
<> 160:d5399cc887bb 185 * you to the article on compare-and swap].
<> 160:d5399cc887bb 186 *
<> 160:d5399cc887bb 187 * @param ptr The target memory location.
<> 160:d5399cc887bb 188 * @param[in,out] expectedCurrentValue A pointer to some location holding the
<> 160:d5399cc887bb 189 * expected current value of the data being set atomically.
<> 160:d5399cc887bb 190 * The computed 'desiredValue' should be a function of this current value.
<> 160:d5399cc887bb 191 * @Note: This is an in-out parameter. In the
<> 160:d5399cc887bb 192 * failure case of atomic_cas (where the
<> 160:d5399cc887bb 193 * destination isn't set), the pointee of expectedCurrentValue is
<> 160:d5399cc887bb 194 * updated with the current value.
<> 160:d5399cc887bb 195 * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'.
<> 160:d5399cc887bb 196 *
<> 160:d5399cc887bb 197 * @return true if the memory location was atomically
<> 160:d5399cc887bb 198 * updated with the desired value (after verifying
<> 160:d5399cc887bb 199 * that it contained the expectedCurrentValue),
<> 160:d5399cc887bb 200 * false otherwise. In the failure case,
<> 160:d5399cc887bb 201 * exepctedCurrentValue is updated with the new
<> 160:d5399cc887bb 202 * value of the target memory location.
<> 160:d5399cc887bb 203 *
<> 160:d5399cc887bb 204 * pseudocode:
<> 160:d5399cc887bb 205 * function cas(p : pointer to int, old : pointer to int, new : int) returns bool {
<> 160:d5399cc887bb 206 * if *p != *old {
<> 160:d5399cc887bb 207 * *old = *p
<> 160:d5399cc887bb 208 * return false
<> 160:d5399cc887bb 209 * }
<> 160:d5399cc887bb 210 * *p = new
<> 160:d5399cc887bb 211 * return true
<> 160:d5399cc887bb 212 * }
<> 160:d5399cc887bb 213 *
<> 160:d5399cc887bb 214 * @Note: In the failure case (where the destination isn't set), the value
<> 160:d5399cc887bb 215 * pointed to by expectedCurrentValue is still updated with the current value.
<> 160:d5399cc887bb 216 * This property helps writing concise code for the following incr:
<> 160:d5399cc887bb 217 *
<> 160:d5399cc887bb 218 * function incr(p : pointer to int, a : int) returns int {
<> 160:d5399cc887bb 219 * done = false
<> 160:d5399cc887bb 220 * value = *p // This fetch operation need not be atomic.
<> 160:d5399cc887bb 221 * while not done {
<> 160:d5399cc887bb 222 * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success
<> 160:d5399cc887bb 223 * }
<> 160:d5399cc887bb 224 * return value + a
<> 160:d5399cc887bb 225 * }
<> 160:d5399cc887bb 226 */
<> 160:d5399cc887bb 227 bool core_util_atomic_cas_u32(uint32_t *ptr, uint32_t *expectedCurrentValue, uint32_t desiredValue);
<> 160:d5399cc887bb 228
<> 160:d5399cc887bb 229 /**
<> 160:d5399cc887bb 230 * Atomic compare and set. It compares the contents of a memory location to a
<> 160:d5399cc887bb 231 * given value and, only if they are the same, modifies the contents of that
<> 160:d5399cc887bb 232 * memory location to a given new value. This is done as a single atomic
<> 160:d5399cc887bb 233 * operation. The atomicity guarantees that the new value is calculated based on
<> 160:d5399cc887bb 234 * up-to-date information; if the value had been updated by another thread in
<> 160:d5399cc887bb 235 * the meantime, the write would fail due to a mismatched expectedCurrentValue.
<> 160:d5399cc887bb 236 *
<> 160:d5399cc887bb 237 * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect
<> 160:d5399cc887bb 238 * you to the article on compare-and swap].
<> 160:d5399cc887bb 239 *
<> 160:d5399cc887bb 240 * @param ptr The target memory location.
<> 160:d5399cc887bb 241 * @param[in,out] expectedCurrentValue A pointer to some location holding the
<> 160:d5399cc887bb 242 * expected current value of the data being set atomically.
<> 160:d5399cc887bb 243 * The computed 'desiredValue' should be a function of this current value.
<> 160:d5399cc887bb 244 * @Note: This is an in-out parameter. In the
<> 160:d5399cc887bb 245 * failure case of atomic_cas (where the
<> 160:d5399cc887bb 246 * destination isn't set), the pointee of expectedCurrentValue is
<> 160:d5399cc887bb 247 * updated with the current value.
<> 160:d5399cc887bb 248 * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'.
<> 160:d5399cc887bb 249 *
<> 160:d5399cc887bb 250 * @return true if the memory location was atomically
<> 160:d5399cc887bb 251 * updated with the desired value (after verifying
<> 160:d5399cc887bb 252 * that it contained the expectedCurrentValue),
<> 160:d5399cc887bb 253 * false otherwise. In the failure case,
<> 160:d5399cc887bb 254 * exepctedCurrentValue is updated with the new
<> 160:d5399cc887bb 255 * value of the target memory location.
<> 160:d5399cc887bb 256 *
<> 160:d5399cc887bb 257 * pseudocode:
<> 160:d5399cc887bb 258 * function cas(p : pointer to int, old : pointer to int, new : int) returns bool {
<> 160:d5399cc887bb 259 * if *p != *old {
<> 160:d5399cc887bb 260 * *old = *p
<> 160:d5399cc887bb 261 * return false
<> 160:d5399cc887bb 262 * }
<> 160:d5399cc887bb 263 * *p = new
<> 160:d5399cc887bb 264 * return true
<> 160:d5399cc887bb 265 * }
<> 160:d5399cc887bb 266 *
<> 160:d5399cc887bb 267 * @Note: In the failure case (where the destination isn't set), the value
<> 160:d5399cc887bb 268 * pointed to by expectedCurrentValue is still updated with the current value.
<> 160:d5399cc887bb 269 * This property helps writing concise code for the following incr:
<> 160:d5399cc887bb 270 *
<> 160:d5399cc887bb 271 * function incr(p : pointer to int, a : int) returns int {
<> 160:d5399cc887bb 272 * done = false
<> 160:d5399cc887bb 273 * value = *p // This fetch operation need not be atomic.
<> 160:d5399cc887bb 274 * while not done {
<> 160:d5399cc887bb 275 * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success
<> 160:d5399cc887bb 276 * }
<> 160:d5399cc887bb 277 * return value + a
<> 160:d5399cc887bb 278 * }
<> 160:d5399cc887bb 279 */
<> 160:d5399cc887bb 280 bool core_util_atomic_cas_ptr(void **ptr, void **expectedCurrentValue, void *desiredValue);
<> 160:d5399cc887bb 281
<> 160:d5399cc887bb 282 /**
<> 160:d5399cc887bb 283 * Atomic increment.
<> 160:d5399cc887bb 284 * @param valuePtr Target memory location being incremented.
<> 160:d5399cc887bb 285 * @param delta The amount being incremented.
<> 160:d5399cc887bb 286 * @return The new incremented value.
<> 160:d5399cc887bb 287 */
<> 160:d5399cc887bb 288 uint8_t core_util_atomic_incr_u8(uint8_t *valuePtr, uint8_t delta);
<> 160:d5399cc887bb 289
<> 160:d5399cc887bb 290 /**
<> 160:d5399cc887bb 291 * Atomic increment.
<> 160:d5399cc887bb 292 * @param valuePtr Target memory location being incremented.
<> 160:d5399cc887bb 293 * @param delta The amount being incremented.
<> 160:d5399cc887bb 294 * @return The new incremented value.
<> 160:d5399cc887bb 295 */
<> 160:d5399cc887bb 296 uint16_t core_util_atomic_incr_u16(uint16_t *valuePtr, uint16_t delta);
<> 160:d5399cc887bb 297
<> 160:d5399cc887bb 298 /**
<> 160:d5399cc887bb 299 * Atomic increment.
<> 160:d5399cc887bb 300 * @param valuePtr Target memory location being incremented.
<> 160:d5399cc887bb 301 * @param delta The amount being incremented.
<> 160:d5399cc887bb 302 * @return The new incremented value.
<> 160:d5399cc887bb 303 */
<> 160:d5399cc887bb 304 uint32_t core_util_atomic_incr_u32(uint32_t *valuePtr, uint32_t delta);
<> 160:d5399cc887bb 305
<> 160:d5399cc887bb 306 /**
<> 160:d5399cc887bb 307 * Atomic increment.
<> 160:d5399cc887bb 308 * @param valuePtr Target memory location being incremented.
<> 160:d5399cc887bb 309 * @param delta The amount being incremented in bytes.
<> 160:d5399cc887bb 310 * @return The new incremented value.
<> 160:d5399cc887bb 311 *
<> 160:d5399cc887bb 312 * @note The type of the pointer argument is not taken into account
<> 160:d5399cc887bb 313 * and the pointer is incremented by bytes.
<> 160:d5399cc887bb 314 */
<> 160:d5399cc887bb 315 void *core_util_atomic_incr_ptr(void **valuePtr, ptrdiff_t delta);
<> 160:d5399cc887bb 316
<> 160:d5399cc887bb 317 /**
<> 160:d5399cc887bb 318 * Atomic decrement.
<> 160:d5399cc887bb 319 * @param valuePtr Target memory location being decremented.
<> 160:d5399cc887bb 320 * @param delta The amount being decremented.
<> 160:d5399cc887bb 321 * @return The new decremented value.
<> 160:d5399cc887bb 322 */
<> 160:d5399cc887bb 323 uint8_t core_util_atomic_decr_u8(uint8_t *valuePtr, uint8_t delta);
<> 160:d5399cc887bb 324
<> 160:d5399cc887bb 325 /**
<> 160:d5399cc887bb 326 * Atomic decrement.
<> 160:d5399cc887bb 327 * @param valuePtr Target memory location being decremented.
<> 160:d5399cc887bb 328 * @param delta The amount being decremented.
<> 160:d5399cc887bb 329 * @return The new decremented value.
<> 160:d5399cc887bb 330 */
<> 160:d5399cc887bb 331 uint16_t core_util_atomic_decr_u16(uint16_t *valuePtr, uint16_t delta);
<> 160:d5399cc887bb 332
<> 160:d5399cc887bb 333 /**
<> 160:d5399cc887bb 334 * Atomic decrement.
<> 160:d5399cc887bb 335 * @param valuePtr Target memory location being decremented.
<> 160:d5399cc887bb 336 * @param delta The amount being decremented.
<> 160:d5399cc887bb 337 * @return The new decremented value.
<> 160:d5399cc887bb 338 */
<> 160:d5399cc887bb 339 uint32_t core_util_atomic_decr_u32(uint32_t *valuePtr, uint32_t delta);
<> 160:d5399cc887bb 340
<> 160:d5399cc887bb 341 /**
<> 160:d5399cc887bb 342 * Atomic decrement.
<> 160:d5399cc887bb 343 * @param valuePtr Target memory location being decremented.
<> 160:d5399cc887bb 344 * @param delta The amount being decremented in bytes.
<> 160:d5399cc887bb 345 * @return The new decremented value.
<> 160:d5399cc887bb 346 *
<> 160:d5399cc887bb 347 * @note The type of the pointer argument is not taken into account
<> 160:d5399cc887bb 348 * and the pointer is decremented by bytes
<> 160:d5399cc887bb 349 */
<> 160:d5399cc887bb 350 void *core_util_atomic_decr_ptr(void **valuePtr, ptrdiff_t delta);
<> 160:d5399cc887bb 351
<> 160:d5399cc887bb 352 #ifdef __cplusplus
<> 160:d5399cc887bb 353 } // extern "C"
<> 160:d5399cc887bb 354 #endif
<> 160:d5399cc887bb 355
<> 160:d5399cc887bb 356
<> 160:d5399cc887bb 357 #endif // __MBED_UTIL_CRITICAL_H__
<> 160:d5399cc887bb 358
<> 160:d5399cc887bb 359 /** @}*/