lib: cmsis_rtos_v2: Dynamic memory pools

Implemented dynamic allocation of memory pools in a similar to manner to
what was already implemented for message queues. Added all the same
checks on size vs. maximum allowed and current heap.

Added an additional Kconfig variable to define the maximum size of a
dynamically allocated memory pool.

Signed-off-by: Carlos Stuart <[email protected]>

Author: carlos-stuart

lib/cmsis_rtos_v2/Kconfig

@@ -61,6 +61,12 @@ config CMSIS_V2_MEM_SLAB_MAX_COUNT
 	help
 	  Mention maximum number of memory slabs in CMSIS RTOS V2 compliant application.
 
+config CMSIS_V2_MEM_SLAB_MAX_DYNAMIC_SIZE
+	int "Maximum dynamic mem slab/pool size in CMSIS RTOS V2 application"
+	default 0
+	help
+	  Mention maximum dynamic size of memory slabs/pools in CMSIS RTOS V2 compliant application.
+
 config CMSIS_V2_MSGQ_MAX_COUNT
 	int "Maximum message queue count in CMSIS RTOS V2 application"
 	default 5

lib/cmsis_rtos_v2/mempool.c

@@ -29,20 +29,20 @@ osMemoryPoolId_t osMemoryPoolNew(uint32_t block_count, uint32_t block_size,
 {
 	struct cv2_mslab *mslab;
 
+	BUILD_ASSERT_MSG(CONFIG_HEAP_MEM_POOL_SIZE >=
+			 CONFIG_CMSIS_V2_MEM_SLAB_MAX_DYNAMIC_SIZE,
+			 "heap must be configured to be at least the max dynamic size");
+
 	if (k_is_in_isr()) {
 		return NULL;
 	}
 
-	if (attr == NULL) {
-		attr = &init_mslab_attrs;
+	if ((attr != NULL) && (attr->mp_size < block_count * block_size)) {
+		return NULL;
 	}
 
-	/* This implementation requires memory to be allocated by the
-	 * App layer
-	 */
-	if ((attr->mp_mem == NULL) ||
-	    (attr->mp_size < block_count * block_size)) {
-		return NULL;
+	if (attr == NULL) {
+		attr = &init_mslab_attrs;
 	}
 
 	if (k_mem_slab_alloc(&cv2_mem_slab, (void **)&mslab, 100) == 0) {
@@ -51,7 +51,23 @@ osMemoryPoolId_t osMemoryPoolNew(uint32_t block_count, uint32_t block_size,
 		return NULL;
 	}
 
-	k_mem_slab_init(&mslab->z_mslab, attr->mp_mem, block_size, block_count);
+	if (attr->mp_mem == NULL) {
+		__ASSERT((block_count * block_size) <=
+			 CONFIG_CMSIS_V2_MEM_SLAB_MAX_DYNAMIC_SIZE,
+			 "memory slab/pool size exceeds dynamic maximum");
+
+		mslab->pool = k_calloc(block_count, block_size);
+		if (mslab->pool == NULL) {
+			k_mem_slab_free(&cv2_mem_slab, (void *) &mslab);
+			return NULL;
+		}
+		mslab->is_dynamic_allocation = TRUE;
+	} else {
+		mslab->pool = attr->mp_mem;
+		mslab->is_dynamic_allocation = FALSE;
+	}
+
+	k_mem_slab_init(&mslab->z_mslab, mslab->pool, block_size, block_count);
 	memcpy(mslab->name, attr->name, 16);
 
 	return (osMemoryPoolId_t)mslab;
@@ -207,6 +223,9 @@ osStatus_t osMemoryPoolDelete(osMemoryPoolId_t mp_id)
 	 * supported in Zephyr.
 	 */
 
+	if (mslab->is_dynamic_allocation) {
+		k_free(mslab->pool);
+	}
 	k_mem_slab_free(&cv2_mem_slab, (void *)&mslab);
 
 	return osOK;

lib/cmsis_rtos_v2/wrapper.h

@@ -45,6 +45,8 @@ struct cv2_sem {
 
 struct cv2_mslab {
 	struct k_mem_slab z_mslab;
+	void *pool;
+	char is_dynamic_allocation;
 	char name[16];
 };