3 files changed, 64 insertions, 1 deletions

diff --git a/py/malloc.c b/py/malloc.c
index c65d38a968..4f01dc63f5 100644
--- a/py/malloc.c
+++ b/py/malloc.c
@@ -2,8 +2,15 @@
 #include <stdlib.h>
 
 #include "misc.h"
+#include "mpconfig.h"
 
+#if MICROPY_MEM_STATS
 static int total_bytes_allocated = 0;
+static int current_bytes_allocated = 0;
+static int peak_bytes_allocated = 0;
+
+#define UPDATE_PEAK() { if (current_bytes_allocated > peak_bytes_allocated) peak_bytes_allocated = current_bytes_allocated; }
+#endif
 
 void *m_malloc(int num_bytes) {
     if (num_bytes == 0) {
@@ -14,7 +21,11 @@ void *m_malloc(int num_bytes) {
         printf("could not allocate memory, allocating %d bytes\n", num_bytes);
         return NULL;
     }
+#if MICROPY_MEM_STATS
     total_bytes_allocated += num_bytes;
+    current_bytes_allocated += num_bytes;
+    UPDATE_PEAK();
+#endif
     return ptr;
 }
 
@@ -27,7 +38,11 @@ void *m_malloc0(int num_bytes) {
         printf("could not allocate memory, allocating %d bytes\n", num_bytes);
         return NULL;
     }
+#if MICROPY_MEM_STATS
     total_bytes_allocated += num_bytes;
+    current_bytes_allocated += num_bytes;
+    UPDATE_PEAK();
+#endif
     return ptr;
 }
 
@@ -41,7 +56,17 @@ void *m_realloc(void *ptr, int old_num_bytes, int new_num_bytes) {
         printf("could not allocate memory, reallocating %d bytes\n", new_num_bytes);
         return NULL;
     }
-    total_bytes_allocated += new_num_bytes;
+#if MICROPY_MEM_STATS
+    // At first thought, "Total bytes allocated" should only grow,
+    // after all, it's *total*. But consider for example 2K block
+    // shrunk to 1K and then grown to 2K again. It's still 2K
+    // allocated total. If we process only positive increments,
+    // we'll count 3K.
+    int diff = new_num_bytes - old_num_bytes;
+    total_bytes_allocated += diff;
+    current_bytes_allocated += diff;
+    UPDATE_PEAK();
+#endif
     return ptr;
 }
 
@@ -49,8 +74,31 @@ void m_free(void *ptr, int num_bytes) {
     if (ptr != NULL) {
         free(ptr);
     }
+#if MICROPY_MEM_STATS
+    current_bytes_allocated -= num_bytes;
+#endif
 }
 
 int m_get_total_bytes_allocated(void) {
+#if MICROPY_MEM_STATS
     return total_bytes_allocated;
+#else
+    return -1;
+#endif
+}
+
+int m_get_current_bytes_allocated(void) {
+#if MICROPY_MEM_STATS
+    return current_bytes_allocated;
+#else
+    return -1;
+#endif
+}
+
+int m_get_peak_bytes_allocated(void) {
+#if MICROPY_MEM_STATS
+    return peak_bytes_allocated;
+#else
+    return -1;
+#endif
 }
diff --git a/py/misc.h b/py/misc.h
index 9f83ab526f..153218ba2f 100644
--- a/py/misc.h
+++ b/py/misc.h
@@ -32,6 +32,8 @@ void *m_realloc(void *ptr, int old_num_bytes, int new_num_bytes);
 void m_free(void *ptr, int num_bytes);
 
 int m_get_total_bytes_allocated(void);
+int m_get_current_bytes_allocated(void);
+int m_get_peak_bytes_allocated(void);
 
 /** unichar / UTF-8 *********************************************/
 
diff --git a/py/mpconfig.h b/py/mpconfig.h
new file mode 100644
index 0000000000..17c5a770c4
--- /dev/null
+++ b/py/mpconfig.h
@@ -0,0 +1,13 @@
+// This file contains default configuration settings for MicroPython.
+// You can override any of these options using mpconfigport.h file located
+// in a directory of your port.
+
+#include <mpconfigport.h>
+
+// Any options not explicitly set in mpconfigport.h will get default
+// values below.
+
+// Whether to collect memory allocation stats
+#ifndef MICROPY_MEM_STATS
+#define MICROPY_MEM_STATS (1)
+#endif