mempool: add the minimum size configuration of mempool

The minimum size of mempool can be configured through CONFIG_MM_MPOOL_MINISIZE

Signed-off-by: liwenxiang1 <liwenxiang1@xiaomi.com>

mm/Kconfig

@@ -216,10 +216,11 @@ config MM_HEAP_MEMPOOL_THRESHOLD
 		== 0 Enable pool feature, but disable the umm/kmm pool function.
 		 < 0 Disable pool feature.
 
+if MM_HEAP_MEMPOOL_THRESHOLD > 0
+
 config MM_HEAP_MEMPOOL_EXPAND_SIZE
 	int "The expand size for each mempool in multiple mempool"
 	default 4096
-	depends on MM_HEAP_MEMPOOL_THRESHOLD > 0
 	---help---
 		This size describes the size of each expansion of each memory
 		pool with insufficient memory in the multi-level memory pool.
@@ -227,17 +228,23 @@ config MM_HEAP_MEMPOOL_EXPAND_SIZE
 config MM_HEAP_MEMPOOL_DICTIONARY_EXPAND_SIZE
 	int "The expand size for multiple mempool's dictionary"
 	default MM_HEAP_MEMPOOL_EXPAND_SIZE
-	depends on MM_HEAP_MEMPOOL_THRESHOLD > 0
 	---help---
 		This size describes the multiple mempool dictionary expand.
 
 config MM_HEAP_MEMPOOL_CHUNK_SIZE
 	int "The multiples pool chunk size"
 	default 0
-	depends on MM_HEAP_MEMPOOL_THRESHOLD > 0
 	---help---
 		This size describes the multiple mempool chunk size.
 
+config MM_MIN_BLKSIZE
+	int "Minimum memory block size"
+	default 0
+	---help---
+		Users can configure the minimum memory block size as needed
+
+endif # MM_HEAP_MEMPOOL_THRESHOLD > 0
+
 config MM_HEAP_MEMPOOL_BACKTRACE_SKIP
 	int "The skip depth of backtrace for mempool"
 	default 6

mm/mm_heap/mm_initialize.c

@@ -316,7 +316,11 @@ mm_initialize_pool(FAR const char *name,
 
       for (i = 0; i < MEMPOOL_NPOOLS; i++)
         {
+#  if CONFIG_MM_MIN_BLKSIZE != 0
+          poolsize[i] = (i + 1) * CONFIG_MM_MIN_BLKSIZE;
+#  else
           poolsize[i] = (i + 1) * MM_MIN_CHUNK;
+#  endif
         }
 
       def.poolsize        = poolsize;

mm/tlsf/mm_tlsf.c

@@ -1021,7 +1021,11 @@ mm_initialize_pool(FAR const char *name,
 
       for (i = 0; i < MEMPOOL_NPOOLS; i++)
         {
+#  if CONFIG_MM_MIN_BLKSIZE != 0
+          poolsize[i] = (i + 1) * CONFIG_MM_MIN_BLKSIZE;
+#  else
           poolsize[i] = (i + 1) * tlsf_align_size();
+#  endif
         }
 
       def.poolsize        = poolsize;