diff --git a/components/freertos/FreeRTOS-Kernel/idf_changes.md b/components/freertos/FreeRTOS-Kernel/idf_changes.md index a3ef845460..83bee68433 100644 --- a/components/freertos/FreeRTOS-Kernel/idf_changes.md +++ b/components/freertos/FreeRTOS-Kernel/idf_changes.md @@ -123,6 +123,8 @@ The following functions were modified to accommodate SMP behavior: - In SMP, the function now disables interrupts to ensure that the calling task does not switch cores while checking its own copy of `uxSchedulerSuspended`. - `prvAddCurrentTaskToDelayedList()` - 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. ### Critical Section Changes diff --git a/components/freertos/FreeRTOS-Kernel/stream_buffer.c b/components/freertos/FreeRTOS-Kernel/stream_buffer.c index 50c2fb13ca..988eb3f5f7 100644 --- a/components/freertos/FreeRTOS-Kernel/stream_buffer.c +++ b/components/freertos/FreeRTOS-Kernel/stream_buffer.c @@ -6,7 +6,7 @@ * * SPDX-License-Identifier: MIT * - * SPDX-FileContributor: 2023 Espressif Systems (Shanghai) CO LTD + * SPDX-FileContributor: 2023-2024 Espressif Systems (Shanghai) CO LTD * * Permission is hereby granted, free of charge, to any person obtaining a copy of * this software and associated documentation files (the "Software"), to deal in @@ -977,7 +977,19 @@ size_t xStreamBufferReceive( StreamBufferHandle_t xStreamBuffer, /* Wait for data to be available. */ traceBLOCKING_ON_STREAM_BUFFER_RECEIVE( xStreamBuffer ); ( void ) xTaskNotifyWait( ( uint32_t ) 0, ( uint32_t ) 0, NULL, xTicksToWait ); - pxStreamBuffer->xTaskWaitingToReceive = NULL; + + /* In SMP mode, the task may have been woken and scheduled on + * another core. Hence, we must clear the xTaskWaitingToReceive + * handle in a critical section. */ + #if ( configNUMBER_OF_CORES > 1 ) + taskENTER_CRITICAL( &( pxStreamBuffer->xStreamBufferLock ) ); + #endif /* configNUMBER_OF_CORES > 1 */ + { + pxStreamBuffer->xTaskWaitingToReceive = NULL; + } + #if ( configNUMBER_OF_CORES > 1 ) + taskEXIT_CRITICAL( &( pxStreamBuffer->xStreamBufferLock ) ); + #endif /* configNUMBER_OF_CORES > 1 */ /* Recheck the data available after blocking. */ xBytesAvailable = prvBytesInBuffer( pxStreamBuffer ); @@ -1421,7 +1433,7 @@ static void prvInitialiseNewStreamBuffer( StreamBuffer_t * const pxStreamBuffer, * result in confusion as to what is actually being observed. */ const BaseType_t xWriteValue = 0x55; configASSERT( memset( pucBuffer, ( int ) xWriteValue, xBufferSizeBytes ) == pucBuffer ); - (void)xWriteValue; + ( void ) xWriteValue; } /*lint !e529 !e438 xWriteValue is only used if configASSERT() is defined. */ #endif