pinebuds/rtos/rtx5/rtx_memory.c

219 lines
6.5 KiB
C

/*
* Copyright (c) 2013-2018 Arm Limited. All rights reserved.
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the License); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an AS IS BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* -----------------------------------------------------------------------------
*
* Project: CMSIS-RTOS RTX
* Title: Memory functions
*
* -----------------------------------------------------------------------------
*/
#include "rtx_lib.h"
// Memory Pool Header structure
typedef struct {
uint32_t size; // Memory Pool size
uint32_t used; // Used Memory
} mem_head_t;
// Memory Block Header structure
typedef struct mem_block_s {
struct mem_block_s *next; // Next Memory Block in list
uint32_t info; // Block Info or max used Memory (in last block)
} mem_block_t;
// Memory Block Info: Length = <31:2>:'00', Type = <1:0>
#define MB_INFO_LEN_MASK 0xFFFFFFFCU // Length mask
#define MB_INFO_TYPE_MASK 0x00000003U // Type mask
// Memory Head Pointer
__STATIC_INLINE mem_head_t *MemHeadPtr (void *mem) {
//lint -e{9079} -e{9087} "conversion from pointer to void to pointer to other type" [MISRA Note 6]
return ((mem_head_t *)mem);
}
// Memory Block Pointer
__STATIC_INLINE mem_block_t *MemBlockPtr (void *mem, uint32_t offset) {
uint32_t addr;
mem_block_t *ptr;
//lint --e{923} --e{9078} "cast between pointer and unsigned int" [MISRA Note 8]
addr = (uint32_t)mem + offset;
ptr = (mem_block_t *)addr;
return ptr;
}
// ==== Library functions ====
/// Initialize Memory Pool with variable block size.
/// \param[in] mem pointer to memory pool.
/// \param[in] size size of a memory pool in bytes.
/// \return 1 - success, 0 - failure.
__WEAK uint32_t osRtxMemoryInit (void *mem, uint32_t size) {
mem_head_t *head;
mem_block_t *ptr;
// Check parameters
//lint -e{923} "cast from pointer to unsigned int" [MISRA Note 7]
if ((mem == NULL) || (((uint32_t)mem & 7U) != 0U) || ((size & 7U) != 0U) ||
(size < (sizeof(mem_head_t) + (2U*sizeof(mem_block_t))))) {
EvrRtxMemoryInit(mem, size, 0U);
//lint -e{904} "Return statement before end of function" [MISRA Note 1]
return 0U;
}
// Initialize memory pool header
head = MemHeadPtr(mem);
head->size = size;
head->used = sizeof(mem_head_t) + sizeof(mem_block_t);
// Initialize first and last block header
ptr = MemBlockPtr(mem, sizeof(mem_head_t));
ptr->next = MemBlockPtr(mem, size - sizeof(mem_block_t));
ptr->next->next = NULL;
ptr->next->info = sizeof(mem_head_t) + sizeof(mem_block_t);
ptr->info = 0U;
EvrRtxMemoryInit(mem, size, 1U);
return 1U;
}
/// Allocate a memory block from a Memory Pool.
/// \param[in] mem pointer to memory pool.
/// \param[in] size size of a memory block in bytes.
/// \param[in] type memory block type: 0 - generic, 1 - control block
/// \return allocated memory block or NULL in case of no memory is available.
__WEAK void *osRtxMemoryAlloc (void *mem, uint32_t size, uint32_t type) {
mem_block_t *ptr;
mem_block_t *p, *p_new;
uint32_t block_size;
uint32_t hole_size;
// Check parameters
if ((mem == NULL) || (size == 0U) || ((type & ~MB_INFO_TYPE_MASK) != 0U)) {
EvrRtxMemoryAlloc(mem, size, type, NULL);
//lint -e{904} "Return statement before end of function" [MISRA Note 1]
return NULL;
}
// Add block header to size
block_size = size + sizeof(mem_block_t);
// Make sure that block is 8-byte aligned
block_size = (block_size + 7U) & ~((uint32_t)7U);
// Search for hole big enough
p = MemBlockPtr(mem, sizeof(mem_head_t));
for (;;) {
//lint -e{923} -e{9078} "cast from pointer to unsigned int"
hole_size = (uint32_t)p->next - (uint32_t)p;
hole_size -= p->info & MB_INFO_LEN_MASK;
if (hole_size >= block_size) {
// Hole found
break;
}
p = p->next;
if (p->next == NULL) {
// Failed (end of list)
EvrRtxMemoryAlloc(mem, size, type, NULL);
//lint -e{904} "Return statement before end of function" [MISRA Note 1]
return NULL;
}
}
// Update used memory
(MemHeadPtr(mem))->used += block_size;
// Update max used memory
p_new = MemBlockPtr(mem, (MemHeadPtr(mem))->size - sizeof(mem_block_t));
if (p_new->info < (MemHeadPtr(mem))->used) {
p_new->info = (MemHeadPtr(mem))->used;
}
// Allocate block
if (p->info == 0U) {
// No block allocated, set info of first element
p->info = block_size | type;
ptr = MemBlockPtr(p, sizeof(mem_block_t));
} else {
// Insert new element into the list
p_new = MemBlockPtr(p, p->info & MB_INFO_LEN_MASK);
p_new->next = p->next;
p_new->info = block_size | type;
p->next = p_new;
ptr = MemBlockPtr(p_new, sizeof(mem_block_t));
}
EvrRtxMemoryAlloc(mem, size, type, ptr);
return ptr;
}
/// Return an allocated memory block back to a Memory Pool.
/// \param[in] mem pointer to memory pool.
/// \param[in] block memory block to be returned to the memory pool.
/// \return 1 - success, 0 - failure.
__WEAK uint32_t osRtxMemoryFree (void *mem, void *block) {
const mem_block_t *ptr;
mem_block_t *p, *p_prev;
// Check parameters
if ((mem == NULL) || (block == NULL)) {
EvrRtxMemoryFree(mem, block, 0U);
//lint -e{904} "Return statement before end of function" [MISRA Note 1]
return 0U;
}
// Memory block header
ptr = MemBlockPtr(block, 0U);
ptr--;
// Search for block header
p_prev = NULL;
p = MemBlockPtr(mem, sizeof(mem_head_t));
while (p != ptr) {
p_prev = p;
p = p->next;
if (p == NULL) {
// Not found
EvrRtxMemoryFree(mem, block, 0U);
//lint -e{904} "Return statement before end of function" [MISRA Note 1]
return 0U;
}
}
// Update used memory
(MemHeadPtr(mem))->used -= p->info & MB_INFO_LEN_MASK;
// Free block
if (p_prev == NULL) {
// Release first block, only set info to 0
p->info = 0U;
} else {
// Discard block from chained list
p_prev->next = p->next;
}
EvrRtxMemoryFree(mem, block, 1U);
return 1U;
}