[vlc-devel] [PATCH 7/8] mmal: Use atomic operations for refcounting

[Julian Scheel]

Signed-off-by: Julian Scheel <julian at jusst.de>
---
 modules/hw/mmal/codec.c       | 8 ++++----
 modules/hw/mmal/deinterlace.c | 9 +++++----
 modules/hw/mmal/vout.c        | 8 +++-----
 3 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/modules/hw/mmal/codec.c b/modules/hw/mmal/codec.c
index 183981c..36af836 100644
--- a/modules/hw/mmal/codec.c
+++ b/modules/hw/mmal/codec.c
@@ -438,7 +438,7 @@ static int send_output_buffer(decoder_t *dec)
         ret = -1;
         goto err;
     }
-    sys->output_in_transit++;
+    atomic_fetch_add(&sys->output_in_transit, 1);
 
     return ret;
 
@@ -456,7 +456,7 @@ static void fill_output_port(decoder_t *dec)
     unsigned max_buffers_in_transit = __MAX(sys->output_pool->headers_num,
             MIN_NUM_BUFFERS_IN_TRANSIT);
     unsigned buffers_available = mmal_queue_length(sys->output_pool->queue);
-    unsigned buffers_to_send = max_buffers_in_transit - sys->output_in_transit;
+    unsigned buffers_to_send = max_buffers_in_transit - atomic_load(&sys->output_in_transit);
     unsigned i;
 
     if (buffers_to_send > buffers_available)
@@ -464,7 +464,7 @@ static void fill_output_port(decoder_t *dec)
 
 #ifndef NDEBUG
     msg_Dbg(dec, "Send %d buffers to output port (available: %d, in_transit: %d, buffer_num: %d)",
-                    buffers_to_send, buffers_available, sys->output_in_transit,
+                    buffers_to_send, buffers_available, atomic_load(&sys->output_in_transit),
                     sys->output->buffer_num);
 #endif
     for (i = 0; i < buffers_to_send; ++i)
@@ -656,7 +656,7 @@ static void output_port_cb(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
             buffer->data = NULL;
             mmal_buffer_header_release(buffer);
         }
-        sys->output_in_transit--;
+        atomic_fetch_sub(&sys->output_in_transit, 1);
     } else if (buffer->cmd == MMAL_EVENT_FORMAT_CHANGED) {
         fmt = mmal_event_format_changed_get(buffer);
 
diff --git a/modules/hw/mmal/deinterlace.c b/modules/hw/mmal/deinterlace.c
index d8e3172..2ba63cd 100644
--- a/modules/hw/mmal/deinterlace.c
+++ b/modules/hw/mmal/deinterlace.c
@@ -30,6 +30,7 @@
 #include <vlc_common.h>
 #include <vlc_plugin.h>
 #include <vlc_filter.h>
+#include <vlc_atomic.h>
 
 #include "mmal_picture.h"
 
@@ -382,7 +383,7 @@ static int send_output_buffer(filter_t *filter)
         picture_Release(picture);
         ret = -1;
     } else {
-        sys->output_in_transit++;
+        atomic_fetch_add(&sys->output_in_transit, 1);
         vlc_cond_signal(&sys->buffer_cond);
     }
     vlc_mutex_unlock(&sys->buffer_cond_mutex);
@@ -471,7 +472,7 @@ static picture_t *deinterlace(filter_t *filter, picture_t *picture)
         msg_Err(filter, "Failed to send buffer to input port (status=%"PRIx32" %s)",
                 status, mmal_status_to_string(status));
     } else {
-        sys->input_in_transit++;
+        atomic_fetch_add(&sys->input_in_transit, 1);
         vlc_cond_signal(&sys->buffer_cond);
     }
     vlc_mutex_unlock(&sys->buffer_cond_mutex);
@@ -527,7 +528,7 @@ static void input_port_cb(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
     if (picture)
         picture_Release(picture);
 
-    sys->input_in_transit--;
+    atomic_fetch_sub(&sys->input_in_transit, 1);
     vlc_cond_signal(&sys->buffer_cond);
     vlc_mutex_unlock(&sys->buffer_cond_mutex);
 }
@@ -548,7 +549,7 @@ static void output_port_cb(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
             buffer->user_data = NULL;
         }
 
-        sys->output_in_transit--;
+        atomic_fetch_sub(&sys->output_in_transit, 1);
         vlc_cond_signal(&sys->buffer_cond);
         vlc_mutex_unlock(&sys->buffer_cond_mutex);
     } else if (buffer->cmd == MMAL_EVENT_FORMAT_CHANGED) {
diff --git a/modules/hw/mmal/vout.c b/modules/hw/mmal/vout.c
index 569b8a3..6654db2 100644
--- a/modules/hw/mmal/vout.c
+++ b/modules/hw/mmal/vout.c
@@ -564,12 +564,10 @@ static void vd_display(vout_display_t *vd, picture_t *picture,
         buffer->cmd = 0;
         buffer->length = sys->input->buffer_size;
 
-        vlc_mutex_lock(&sys->buffer_mutex);
         status = mmal_port_send_buffer(sys->input, buffer);
         if (status == MMAL_SUCCESS)
-            ++sys->buffers_in_transit;
+            atomic_fetch_add(&sys->buffers_in_transit, 1);
 
-        vlc_mutex_unlock(&sys->buffer_mutex);
         if (status != MMAL_SUCCESS) {
             msg_Err(vd, "Failed to send buffer to input port. Frame dropped");
             picture_Release(picture);
@@ -590,7 +588,7 @@ static void vd_display(vout_display_t *vd, picture_t *picture,
     sys->next_phase_check = (sys->next_phase_check + 1) % PHASE_CHECK_INTERVAL;
 
     vlc_mutex_lock(&sys->buffer_mutex);
-    while (sys->buffers_in_transit >= MAX_BUFFERS_IN_TRANSIT)
+    while (atomic_load(&sys->buffers_in_transit) >= MAX_BUFFERS_IN_TRANSIT)
         vlc_cond_wait(&sys->buffer_cond, &sys->buffer_mutex);
     vlc_mutex_unlock(&sys->buffer_mutex);
 }
@@ -688,7 +686,7 @@ static void input_port_cb(MMAL_PORT_T *port, MMAL_BUFFER_HEADER_T *buffer)
         picture_Release(picture);
 
     vlc_mutex_lock(&sys->buffer_mutex);
-    --sys->buffers_in_transit;
+    atomic_fetch_sub(&sys->buffers_in_transit, 1);
     vlc_cond_signal(&sys->buffer_cond);
     vlc_mutex_unlock(&sys->buffer_mutex);
 }
-- 
2.4.0