Merge branch 'fix/freertos_race_cond_in_stream_buffers_send' into 'master'

fix(freertos): Fixed SMP race condition in xStreamBufferSend()

Closes IDF-11376

See merge request espressif/esp-idf!34230

components/freertos/FreeRTOS-Kernel/idf_changes.md

@@ -125,6 +125,8 @@ The following functions were modified to accommodate SMP behavior:
   - Added extra check to see if current blocking task has already been deleted by the other core.
 - `xStreamBufferReceive()`
   - Added a critical section for setting `xTaskWaitingToReceive` to `NULL` so that the write is SMP safe.
+- `xStreamBufferSend()`
+  - Added a critical section for setting `xTaskWaitingToSend` to `NULL` so that the write is SMP safe.
 
 ### Critical Section Changes
 

components/freertos/FreeRTOS-Kernel/stream_buffer.c

@@ -774,7 +774,18 @@ size_t xStreamBufferSend( StreamBufferHandle_t xStreamBuffer,
 
             traceBLOCKING_ON_STREAM_BUFFER_SEND( xStreamBuffer );
             ( void ) xTaskNotifyWait( ( uint32_t ) 0, ( uint32_t ) 0, NULL, xTicksToWait );
-            pxStreamBuffer->xTaskWaitingToSend = NULL;
+            /* In SMP mode, the task may have been woken and scheduled on
+             * another core. Hence, we must clear the xTaskWaitingToSend
+             * handle in a critical section. */
+            #if ( configNUMBER_OF_CORES > 1 )
+                taskENTER_CRITICAL( &( pxStreamBuffer->xStreamBufferLock ) );
+            #endif /* configNUMBER_OF_CORES > 1 */
+            {
+                pxStreamBuffer->xTaskWaitingToSend = NULL;
+            }
+            #if ( configNUMBER_OF_CORES > 1 )
+                taskEXIT_CRITICAL( &( pxStreamBuffer->xStreamBufferLock ) );
+            #endif /* configNUMBER_OF_CORES > 1 */
         } while( xTaskCheckForTimeOut( &xTimeOut, &xTicksToWait ) == pdFALSE );
     }
     else