ports: Fix m_realloc/m_free when MICROPY_MALLOC_USES_ALLOCATED_SIZE is set

SamantazFox · SamantazFox · commit b1a653a1e131 · 2025-02-23T23:36:58.000+01:00
When 'MICROPY_MALLOC_USES_ALLOCATED_SIZE' is set, we need to pass the
previously allocated size to 'm_realloc', 'm_realloc_maybe' and 'm_free'.

For the atmel-samd and raspberrypi ports, the variable keeping track of the
allocated buffer size was already present, but not properly used.
For the nordic and stm ports, there was no such veriable. It is now added
only if necessary to save on resources.

Signed-off-by: Samantaz Fox &lt;coding@samantaz.fr&gt;
diff --git a/ports/atmel-samd/audio_dma.c b/ports/atmel-samd/audio_dma.c
@@ -200,15 +200,27 @@ audio_dma_result audio_dma_setup_playback(audio_dma_t *dma,
     }
 
 
-    dma->buffer[0] = (uint8_t *)m_realloc(dma->buffer[0], max_buffer_length);
+    dma->buffer[0] = (uint8_t *)m_realloc(dma->buffer[0],
+        #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+        dma->buffer_length[0], // Old size
+        #endif
+        max_buffer_length);
+
     dma->buffer_length[0] = max_buffer_length;
+
     if (dma->buffer[0] == NULL) {
         return AUDIO_DMA_MEMORY_ERROR;
     }
 
     if (!dma->single_buffer) {
-        dma->buffer[1] = (uint8_t *)m_realloc(dma->buffer[1], max_buffer_length);
+        dma->buffer[1] = (uint8_t *)m_realloc(dma->buffer[1],
+            #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+            dma->buffer_length[1], // Old size
+            #endif
+            max_buffer_length);
+
         dma->buffer_length[1] = max_buffer_length;
+
         if (dma->buffer[1] == NULL) {
             return AUDIO_DMA_MEMORY_ERROR;
         }
diff --git a/ports/nordic/common-hal/audiopwmio/PWMAudioOut.c b/ports/nordic/common-hal/audiopwmio/PWMAudioOut.c
@@ -188,6 +188,26 @@ bool common_hal_audiopwmio_pwmaudioout_deinited(audiopwmio_pwmaudioout_obj_t *se
     return !self->pwm;
 }
 
+static void free_buffers(audiopwmio_pwmaudioout_obj_t *self) {
+    #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+    m_free(self->buffers[0], self->buffer_size[0]);
+    self->buffer_size[0] = 0;
+    #else
+    m_free(self->buffers[0]);
+    #endif
+
+    self->buffers[0] = NULL;
+
+    #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+    m_free(self->buffers[1], self->buffer_size[1]);
+    self->buffer_size[1] = 0;
+    #else
+    m_free(self->buffers[1]);
+    #endif
+
+    self->buffers[1] = NULL;
+}
+
 void common_hal_audiopwmio_pwmaudioout_deinit(audiopwmio_pwmaudioout_obj_t *self) {
     if (common_hal_audiopwmio_pwmaudioout_deinited(self)) {
         return;
@@ -209,11 +229,7 @@ void common_hal_audiopwmio_pwmaudioout_deinit(audiopwmio_pwmaudioout_obj_t *self
 
     self->pwm = NULL;
 
-    m_free(self->buffers[0]);
-    self->buffers[0] = NULL;
-
-    m_free(self->buffers[1]);
-    self->buffers[1] = NULL;
+    free_buffers(self);
 }
 
 void common_hal_audiopwmio_pwmaudioout_play(audiopwmio_pwmaudioout_obj_t *self, mp_obj_t sample, bool loop) {
@@ -235,10 +251,18 @@ void common_hal_audiopwmio_pwmaudioout_play(audiopwmio_pwmaudioout_obj_t *self,
 
     mp_arg_validate_length_max(max_buffer_length, UINT16_MAX, MP_QSTR_buffer);
 
-    uint16_t buffer_length = (uint16_t)max_buffer_length;
-    self->buffers[0] = m_malloc(buffer_length * 2 * sizeof(uint16_t));
+    size_t buffer_size = (size_t)max_buffer_length * 2 * sizeof(uint16_t);
+
+    self->buffers[0] = m_malloc(buffer_size);
+    #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+    self->buffer_size[0] = buffer_size;
+    #endif
+
     if (!self->single_buffer) {
-        self->buffers[1] = m_malloc(buffer_length * 2 * sizeof(uint16_t));
+        self->buffers[1] = m_malloc(buffer_size);
+        #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+        self->buffer_size[1] = buffer_size;
+        #endif
     }
 
 
@@ -274,11 +298,7 @@ void common_hal_audiopwmio_pwmaudioout_stop(audiopwmio_pwmaudioout_obj_t *self)
     self->stopping = false;
     self->paused = false;
 
-    m_free(self->buffers[0]);
-    self->buffers[0] = NULL;
-
-    m_free(self->buffers[1]);
-    self->buffers[1] = NULL;
+    free_buffers(self);
 }
 
 bool common_hal_audiopwmio_pwmaudioout_get_playing(audiopwmio_pwmaudioout_obj_t *self) {
diff --git a/ports/nordic/common-hal/audiopwmio/PWMAudioOut.h b/ports/nordic/common-hal/audiopwmio/PWMAudioOut.h
@@ -12,7 +12,11 @@ typedef struct {
     mp_obj_base_t base;
     mp_obj_t *sample;
     NRF_PWM_Type *pwm;
+
     uint16_t *buffers[2];
+    #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+    size_t buffer_size[2]; // Keeps track of allocated size
+    #endif
 
     uint16_t quiescent_value;
     uint16_t scale;
diff --git a/ports/raspberrypi/audio_dma.c b/ports/raspberrypi/audio_dma.c
@@ -227,15 +227,27 @@ audio_dma_result audio_dma_setup_playback(
         max_buffer_length /= dma->sample_spacing;
     }
 
-    dma->buffer[0] = (uint8_t *)m_realloc(dma->buffer[0], max_buffer_length);
+    dma->buffer[0] = (uint8_t *)m_realloc(dma->buffer[0],
+        #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+        dma->buffer_length[0], // Old size
+        #endif
+        max_buffer_length);
+
     dma->buffer_length[0] = max_buffer_length;
+
     if (dma->buffer[0] == NULL) {
         return AUDIO_DMA_MEMORY_ERROR;
     }
 
     if (!single_buffer) {
-        dma->buffer[1] = (uint8_t *)m_realloc(dma->buffer[1], max_buffer_length);
+        dma->buffer[1] = (uint8_t *)m_realloc(dma->buffer[1],
+            #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+            dma->buffer_length[1], // Old size
+            #endif
+            max_buffer_length);
+
         dma->buffer_length[1] = max_buffer_length;
+
         if (dma->buffer[1] == NULL) {
             return AUDIO_DMA_MEMORY_ERROR;
         }
@@ -419,16 +431,31 @@ void audio_dma_init(audio_dma_t *dma) {
     dma->buffer[0] = NULL;
     dma->buffer[1] = NULL;
 
+    dma->buffer_length[0] = 0;
+    dma->buffer_length[1] = 0;
+
     dma->channel[0] = NUM_DMA_CHANNELS;
     dma->channel[1] = NUM_DMA_CHANNELS;
 }
 
 void audio_dma_deinit(audio_dma_t *dma) {
+    #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+    m_free(dma->buffer[0], dma->buffer_length[0]);
+    #else
     m_free(dma->buffer[0]);
+    #endif
+
     dma->buffer[0] = NULL;
+    dma->buffer_length[0] = 0;
 
+    #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+    m_free(dma->buffer[1], dma->buffer_length[1]);
+    #else
     m_free(dma->buffer[1]);
+    #endif
+
     dma->buffer[1] = NULL;
+    dma->buffer_length[1] = 0;
 }
 
 bool audio_dma_get_playing(audio_dma_t *dma) {
diff --git a/ports/stm/common-hal/audiopwmio/PWMAudioOut.c b/ports/stm/common-hal/audiopwmio/PWMAudioOut.c
@@ -206,6 +206,11 @@ void common_hal_audiopwmio_pwmaudioout_construct(audiopwmio_pwmaudioout_obj_t *s
     self->buffer[0] = NULL;
     self->buffer[1] = NULL;
 
+    #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+    self->buffer_size[0] = 0;
+    self->buffer_size[1] = 0;
+    #endif
+
     self->quiescent_value = quiescent_value;
 }
 
@@ -214,9 +219,22 @@ bool common_hal_audiopwmio_pwmaudioout_deinited(audiopwmio_pwmaudioout_obj_t *se
 }
 
 static void free_buffers(audiopwmio_pwmaudioout_obj_t *self) {
+    #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+    m_free(self->buffer[0], self->buffer_size[0]);
+    self->buffer_size[0] = 0;
+    #else
     m_free(self->buffer[0]);
+    #endif
+
     self->buffer[0] = NULL;
+
+    #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+    m_free(self->buffer[1], self->buffer_size[1]);
+    self->buffer_size[1] = 0;
+    #else
     m_free(self->buffer[1]);
+    #endif
+
     self->buffer[1] = NULL;
 }
 
@@ -257,11 +275,21 @@ void common_hal_audiopwmio_pwmaudioout_play(audiopwmio_pwmaudioout_obj_t *self,
     if (max_buffer_length > UINT16_MAX) {
         mp_raise_ValueError_varg(MP_ERROR_TEXT("Buffer length %d too big. It must be less than %d"), max_buffer_length, UINT16_MAX);
     }
+
     uint16_t buffer_length = (uint16_t)max_buffer_length / self->bytes_per_sample;
-    self->buffer[0] = m_malloc(buffer_length * sizeof(uint16_t));
+    size_t buffer_size = buffer_length * sizeof(uint16_t);
+
+    self->buffer[0] = m_malloc(buffer_size);
+    #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+    self->buffer_size[0] = buffer_size;
+    #endif
     self->buffer_ptr[0] = self->buffer_length[0] = 0;
+
     if (self->pin[1]) {
-        self->buffer[1] = m_malloc(buffer_length * sizeof(uint16_t));
+        self->buffer[1] = m_malloc(buffer_size);
+        #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+        self->buffer_size[1] = buffer_size;
+        #endif
         self->buffer_ptr[1] = self->buffer_length[1] = 0;
     }
 
diff --git a/ports/stm/common-hal/audiopwmio/PWMAudioOut.h b/ports/stm/common-hal/audiopwmio/PWMAudioOut.h
@@ -14,6 +14,9 @@ typedef struct {
     uint16_t quiescent_value;
 
     uint16_t *buffer[2];
+    #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+    uint16_t buffer_size[2]; // Keeps track of allocated size
+    #endif
     uint16_t buffer_length[2];
     uint16_t buffer_ptr[2];
 
diff --git a/ports/zephyr-cp/common-hal/wifi/ScannedNetworks.c b/ports/zephyr-cp/common-hal/wifi/ScannedNetworks.c
@@ -116,7 +116,12 @@ void wifi_scannednetworks_deinit(wifi_scannednetworks_obj_t *self) {
     // Free any results we don't need.
     while (!k_fifo_is_empty(&self->fifo)) {
         wifi_network_obj_t *entry = k_fifo_get(&self->fifo, K_NO_WAIT);
+
+        #if MICROPY_MALLOC_USES_ALLOCATED_SIZE
+        m_free(entry, sizeof(wifi_network_obj_t));
+        #else
         m_free(entry);
+        #endif
     }
     wifi_scannednetworks_done(self);
 }

Original file line number	Diff line number	Diff line change
`@@ -116,7 +116,12 @@ void wifi_scannednetworks_deinit(wifi_scannednetworks_obj_t *self) {`
`116`	`116`	`// Free any results we don't need.`
`117`	`117`	`while (!k_fifo_is_empty(&self->fifo)) {`
`118`	`118`	`wifi_network_obj_t *entry = k_fifo_get(&self->fifo, K_NO_WAIT);`
	`119`	`+`
	`120`	`+ #if MICROPY_MALLOC_USES_ALLOCATED_SIZE`
	`121`	`+ m_free(entry, sizeof(wifi_network_obj_t));`
	`122`	`+ #else`
`119`	`123`	`m_free(entry);`
	`124`	`+ #endif`
`120`	`125`	`}`
`121`	`126`	`wifi_scannednetworks_done(self);`
`122`	`127`	`}`