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Diff: platform/critical.h
- Revision:
- 160:d5399cc887bb
- Parent:
- 149:156823d33999
--- a/platform/critical.h Tue Feb 28 17:13:35 2017 +0000 +++ b/platform/critical.h Tue Mar 14 16:40:56 2017 +0000 @@ -1,6 +1,3 @@ - -/** \addtogroup platform */ -/** @{*/ /* * Copyright (c) 2015-2016, ARM Limited, All Rights Reserved * SPDX-License-Identifier: Apache-2.0 @@ -18,342 +15,10 @@ * limitations under the License. */ -#ifndef __MBED_UTIL_CRITICAL_H__ -#define __MBED_UTIL_CRITICAL_H__ - -#include <stdbool.h> -#include <stdint.h> -#include <stddef.h> - -#ifdef __cplusplus -extern "C" { -#endif - - -/** Determine the current interrupts enabled state - * - * This function can be called to determine whether or not interrupts are currently enabled. - * \note - * NOTE: - * This function works for both cortex-A and cortex-M, although the underlyng implementation - * differs. - * @return true if interrupts are enabled, false otherwise - */ -bool core_util_are_interrupts_enabled(void); - -/** Mark the start of a critical section - * - * This function should be called to mark the start of a critical section of code. - * \note - * NOTES: - * 1) The use of this style of critical section is targetted at C based implementations. - * 2) These critical sections can be nested. - * 3) The interrupt enable state on entry to the first critical section (of a nested set, or single - * section) will be preserved on exit from the section. - * 4) This implementation will currently only work on code running in privileged mode. - */ -void core_util_critical_section_enter(void); - -/** Mark the end of a critical section - * - * This function should be called to mark the end of a critical section of code. - * \note - * NOTES: - * 1) The use of this style of critical section is targetted at C based implementations. - * 2) These critical sections can be nested. - * 3) The interrupt enable state on entry to the first critical section (of a nested set, or single - * section) will be preserved on exit from the section. - * 4) This implementation will currently only work on code running in privileged mode. - */ -void core_util_critical_section_exit(void); - -/** - * Atomic compare and set. It compares the contents of a memory location to a - * given value and, only if they are the same, modifies the contents of that - * memory location to a given new value. This is done as a single atomic - * operation. The atomicity guarantees that the new value is calculated based on - * up-to-date information; if the value had been updated by another thread in - * the meantime, the write would fail due to a mismatched expectedCurrentValue. - * - * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect - * you to the article on compare-and swap]. - * - * @param ptr The target memory location. - * @param[in,out] expectedCurrentValue A pointer to some location holding the - * expected current value of the data being set atomically. - * The computed 'desiredValue' should be a function of this current value. - * @Note: This is an in-out parameter. In the - * failure case of atomic_cas (where the - * destination isn't set), the pointee of expectedCurrentValue is - * updated with the current value. - * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'. - * - * @return true if the memory location was atomically - * updated with the desired value (after verifying - * that it contained the expectedCurrentValue), - * false otherwise. In the failure case, - * exepctedCurrentValue is updated with the new - * value of the target memory location. - * - * pseudocode: - * function cas(p : pointer to int, old : pointer to int, new : int) returns bool { - * if *p != *old { - * *old = *p - * return false - * } - * *p = new - * return true - * } - * - * @Note: In the failure case (where the destination isn't set), the value - * pointed to by expectedCurrentValue is still updated with the current value. - * This property helps writing concise code for the following incr: - * - * function incr(p : pointer to int, a : int) returns int { - * done = false - * value = *p // This fetch operation need not be atomic. - * while not done { - * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success - * } - * return value + a - * } - */ -bool core_util_atomic_cas_u8(uint8_t *ptr, uint8_t *expectedCurrentValue, uint8_t desiredValue); - -/** - * Atomic compare and set. It compares the contents of a memory location to a - * given value and, only if they are the same, modifies the contents of that - * memory location to a given new value. This is done as a single atomic - * operation. The atomicity guarantees that the new value is calculated based on - * up-to-date information; if the value had been updated by another thread in - * the meantime, the write would fail due to a mismatched expectedCurrentValue. - * - * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect - * you to the article on compare-and swap]. - * - * @param ptr The target memory location. - * @param[in,out] expectedCurrentValue A pointer to some location holding the - * expected current value of the data being set atomically. - * The computed 'desiredValue' should be a function of this current value. - * @Note: This is an in-out parameter. In the - * failure case of atomic_cas (where the - * destination isn't set), the pointee of expectedCurrentValue is - * updated with the current value. - * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'. - * - * @return true if the memory location was atomically - * updated with the desired value (after verifying - * that it contained the expectedCurrentValue), - * false otherwise. In the failure case, - * exepctedCurrentValue is updated with the new - * value of the target memory location. - * - * pseudocode: - * function cas(p : pointer to int, old : pointer to int, new : int) returns bool { - * if *p != *old { - * *old = *p - * return false - * } - * *p = new - * return true - * } - * - * @Note: In the failure case (where the destination isn't set), the value - * pointed to by expectedCurrentValue is still updated with the current value. - * This property helps writing concise code for the following incr: - * - * function incr(p : pointer to int, a : int) returns int { - * done = false - * value = *p // This fetch operation need not be atomic. - * while not done { - * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success - * } - * return value + a - * } - */ -bool core_util_atomic_cas_u16(uint16_t *ptr, uint16_t *expectedCurrentValue, uint16_t desiredValue); +#ifndef MBED_OLD_CRITICAL_H +#define MBED_OLD_CRITICAL_H -/** - * Atomic compare and set. It compares the contents of a memory location to a - * given value and, only if they are the same, modifies the contents of that - * memory location to a given new value. This is done as a single atomic - * operation. The atomicity guarantees that the new value is calculated based on - * up-to-date information; if the value had been updated by another thread in - * the meantime, the write would fail due to a mismatched expectedCurrentValue. - * - * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect - * you to the article on compare-and swap]. - * - * @param ptr The target memory location. - * @param[in,out] expectedCurrentValue A pointer to some location holding the - * expected current value of the data being set atomically. - * The computed 'desiredValue' should be a function of this current value. - * @Note: This is an in-out parameter. In the - * failure case of atomic_cas (where the - * destination isn't set), the pointee of expectedCurrentValue is - * updated with the current value. - * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'. - * - * @return true if the memory location was atomically - * updated with the desired value (after verifying - * that it contained the expectedCurrentValue), - * false otherwise. In the failure case, - * exepctedCurrentValue is updated with the new - * value of the target memory location. - * - * pseudocode: - * function cas(p : pointer to int, old : pointer to int, new : int) returns bool { - * if *p != *old { - * *old = *p - * return false - * } - * *p = new - * return true - * } - * - * @Note: In the failure case (where the destination isn't set), the value - * pointed to by expectedCurrentValue is still updated with the current value. - * This property helps writing concise code for the following incr: - * - * function incr(p : pointer to int, a : int) returns int { - * done = false - * value = *p // This fetch operation need not be atomic. - * while not done { - * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success - * } - * return value + a - * } - */ -bool core_util_atomic_cas_u32(uint32_t *ptr, uint32_t *expectedCurrentValue, uint32_t desiredValue); +#warning critical.h has been replaced by mbed_critical.h, please update to mbed_critical.h [since mbed-os-5.3] +#include "platform/mbed_critical.h" -/** - * Atomic compare and set. It compares the contents of a memory location to a - * given value and, only if they are the same, modifies the contents of that - * memory location to a given new value. This is done as a single atomic - * operation. The atomicity guarantees that the new value is calculated based on - * up-to-date information; if the value had been updated by another thread in - * the meantime, the write would fail due to a mismatched expectedCurrentValue. - * - * Refer to https://en.wikipedia.org/wiki/Compare-and-set [which may redirect - * you to the article on compare-and swap]. - * - * @param ptr The target memory location. - * @param[in,out] expectedCurrentValue A pointer to some location holding the - * expected current value of the data being set atomically. - * The computed 'desiredValue' should be a function of this current value. - * @Note: This is an in-out parameter. In the - * failure case of atomic_cas (where the - * destination isn't set), the pointee of expectedCurrentValue is - * updated with the current value. - * @param[in] desiredValue The new value computed based on '*expectedCurrentValue'. - * - * @return true if the memory location was atomically - * updated with the desired value (after verifying - * that it contained the expectedCurrentValue), - * false otherwise. In the failure case, - * exepctedCurrentValue is updated with the new - * value of the target memory location. - * - * pseudocode: - * function cas(p : pointer to int, old : pointer to int, new : int) returns bool { - * if *p != *old { - * *old = *p - * return false - * } - * *p = new - * return true - * } - * - * @Note: In the failure case (where the destination isn't set), the value - * pointed to by expectedCurrentValue is still updated with the current value. - * This property helps writing concise code for the following incr: - * - * function incr(p : pointer to int, a : int) returns int { - * done = false - * value = *p // This fetch operation need not be atomic. - * while not done { - * done = atomic_cas(p, &value, value + a) // *value gets updated automatically until success - * } - * return value + a - * } - */ -bool core_util_atomic_cas_ptr(void **ptr, void **expectedCurrentValue, void *desiredValue); - -/** - * Atomic increment. - * @param valuePtr Target memory location being incremented. - * @param delta The amount being incremented. - * @return The new incremented value. - */ -uint8_t core_util_atomic_incr_u8(uint8_t *valuePtr, uint8_t delta); - -/** - * Atomic increment. - * @param valuePtr Target memory location being incremented. - * @param delta The amount being incremented. - * @return The new incremented value. - */ -uint16_t core_util_atomic_incr_u16(uint16_t *valuePtr, uint16_t delta); - -/** - * Atomic increment. - * @param valuePtr Target memory location being incremented. - * @param delta The amount being incremented. - * @return The new incremented value. - */ -uint32_t core_util_atomic_incr_u32(uint32_t *valuePtr, uint32_t delta); - -/** - * Atomic increment. - * @param valuePtr Target memory location being incremented. - * @param delta The amount being incremented in bytes. - * @return The new incremented value. - * - * @note The type of the pointer argument is not taken into account - * and the pointer is incremented by bytes. - */ -void *core_util_atomic_incr_ptr(void **valuePtr, ptrdiff_t delta); - -/** - * Atomic decrement. - * @param valuePtr Target memory location being decremented. - * @param delta The amount being decremented. - * @return The new decremented value. - */ -uint8_t core_util_atomic_decr_u8(uint8_t *valuePtr, uint8_t delta); - -/** - * Atomic decrement. - * @param valuePtr Target memory location being decremented. - * @param delta The amount being decremented. - * @return The new decremented value. - */ -uint16_t core_util_atomic_decr_u16(uint16_t *valuePtr, uint16_t delta); - -/** - * Atomic decrement. - * @param valuePtr Target memory location being decremented. - * @param delta The amount being decremented. - * @return The new decremented value. - */ -uint32_t core_util_atomic_decr_u32(uint32_t *valuePtr, uint32_t delta); - -/** - * Atomic decrement. - * @param valuePtr Target memory location being decremented. - * @param delta The amount being decremented in bytes. - * @return The new decremented value. - * - * @note The type of the pointer argument is not taken into account - * and the pointer is decremented by bytes - */ -void *core_util_atomic_decr_ptr(void **valuePtr, ptrdiff_t delta); - -#ifdef __cplusplus -} // extern "C" #endif - - -#endif // __MBED_UTIL_CRITICAL_H__ - -/** @}*/