added configLTO_HELPER setting to prevent the GNU Link Time Optimizer…

… to remove variables used by FreeRTOS Thread Awareness (e.g. from SEGGER).
ErichStyger · Aug 1, 2017 · 6a4af83 · 6a4af83
1 parent c3bc03e
commit 6a4af83
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Showing 6 changed files with 85 additions and 15 deletions.
diff --git a/Beans/FreeRTOS/FreeRTOS.bean b/Beans/FreeRTOS/FreeRTOS.bean
@@ -4,7 +4,7 @@
     <Name>FreeRTOS</Name>
     <Description>FreeRTOS McuOnEclipse Port with FreeRTOS+Trace</Description>
     <Author>Erich Styger</Author>
-    <Version>01.546</Version>
+    <Version>01.548</Version>
     <Icon>FreeRTOS</Icon>
     <TypesFiles>PE,FreeRTOS\FreeRTOS</TypesFiles>
     <FileVersion>6</FileVersion>
@@ -460,6 +460,24 @@ This is defined to be the most efficient, natural, type for the architecture. Fo
               <Popup>false</Popup>
             </TBoolItem>
           </GrupItem>
+          <GrupItem>
+            <TBoolItem>
+              <Name>Enable LinkTimeOptimizer Helper</Name>
+              <Symbol>EnableLTODebugHelper</Symbol>
+              <TypeSpec>typeYesNo</TypeSpec>
+              <Hint>This setting configures the configLTO_HELPER macro. With -LTO (GNU Link Time Optimizer), certain symbols might be optimized which affect kernel aware debugging. This setting disables optimization so debugging is still possible.</Hint>
+              <ItemLevel>BASIC</ItemLevel>
+              <EditLine>false</EditLine>
+              <TypeSpecNameChangeAble>false</TypeSpecNameChangeAble>
+              <DefaultIndex>1</DefaultIndex>
+              <TextValueIndex>false</TextValueIndex>
+              <RuntimeProperty>false</RuntimeProperty>
+              <CanDelete>false</CanDelete>
+              <IconPopup>false</IconPopup>
+              <DefaultValue>false</DefaultValue>
+              <Popup>false</Popup>
+            </TBoolItem>
+          </GrupItem>
           <GrupItem>
             <TBoolItem>
               <Name>uxTopUsedPriority</Name>

diff --git a/Beans/FreeRTOS/FreeRTOS.uis b/Beans/FreeRTOS/FreeRTOS.uis
@@ -1,6 +1,6 @@
 
 [USED_FACES]
-BeanVersion=01.546
+BeanVersion=01.548
 
 InterfacesCount=10
 

diff --git a/Beans/FreeRTOS/FreeRTOSProperties.html b/Beans/FreeRTOS/FreeRTOSProperties.html
@@ -371,6 +371,10 @@
   <b>Enable GDB Debug Helper</b></a> - If enabled, a debug helper for GDB is enabled to do thread stack debugging with a special vPortPendSVHandler(). This setting configures the configGDB_HELPER macro. 
   </li>
   <li>
+  <a name="EnableLTODebugHelper">
+  <b>Enable LinkTimeOptimizer Helper</b></a> - This setting configures the configLTO_HELPER macro. With -LTO (GNU Link Time Optimizer), certain symbols might be optimized which affect kernel aware debugging. This setting disables optimization so debugging is still possible.
+  </li>
+  <li>
   <a name="uxTopUsedPriority">
   <b>uxTopUsedPriority</b></a> - Configures configUSE_TOP_USED_PRIORITY. OpenOCD Thread Aware debugging needs the variable uxTopUsedPriority present.
   </li>

diff --git a/Drivers/freeRTOS/Source/portable/GCC/ARM_CM4F/port.c b/Drivers/freeRTOS/Source/portable/GCC/ARM_CM4F/port.c
@@ -1215,7 +1215,7 @@ void vPortStopTickTimer(void) {
 #if configCPU_FAMILY_IS_ARM_FPU(configCPU_FAMILY) /* has floating point unit */
 #if (configCOMPILER==configCOMPILER_ARM_GCC)
 /* added noinline attribute to prevent the GNU linker to optimize the following function. That symbol is required for the FreeRTOS GDB thread awareness by Segger */
-void __attribute__ ((noinline)) vPortEnableVFP(void) {
+void __attribute__ ((noinline, used)) vPortEnableVFP(void) {
   /* The FPU enable bits are in the CPACR. */
   __asm volatile (
     "  ldr.w r0, =0xE000ED88  \n" /* CAPCR, 0xE000ED88 */
@@ -1849,8 +1849,8 @@ __asm void vPortStartFirstTask(void) {
 /* Need the 'noinline', as latest gcc with -O3 tries to inline it, and gives error message: "Error: symbol `pxCurrentTCBConst2' is already defined" */
 __attribute__((noinline))
 void vPortStartFirstTask(void) {
-#if configUSE_TOP_USED_PRIORITY
-  /* only needed for openOCD thread awareness. It needs the symbol uxTopUsedPriority present after linking */
+#if configUSE_TOP_USED_PRIORITY || configLTO_HELPER
+  /* only needed for openOCD or Segger FreeRTOS thread awareness. It needs the symbol uxTopUsedPriority present after linking */
   {
     extern volatile const int uxTopUsedPriority;
     __attribute__((__unused__)) volatile uint8_t dummy_value_for_openocd;

diff --git a/Drivers/freeRTOS/Source/tasks.c b/Drivers/freeRTOS/Source/tasks.c
@@ -404,12 +404,26 @@ which static variables must be declared volatile. */
 PRIVILEGED_DATA TCB_t * volatile pxCurrentTCB = NULL;
 
 /* Lists for ready and blocked tasks. --------------------*/
-PRIVILEGED_DATA static List_t pxReadyTasksLists[ configMAX_PRIORITIES ];/*< Prioritised ready tasks. */
-PRIVILEGED_DATA static List_t xDelayedTaskList1;						/*< Delayed tasks. */
-PRIVILEGED_DATA static List_t xDelayedTaskList2;						/*< Delayed tasks (two lists are used - one for delays that have overflowed the current tick count. */
-PRIVILEGED_DATA static List_t * volatile pxDelayedTaskList;				/*< Points to the delayed task list currently being used. */
-PRIVILEGED_DATA static List_t * volatile pxOverflowDelayedTaskList;		/*< Points to the delayed task list currently being used to hold tasks that have overflowed the current tick count. */
-PRIVILEGED_DATA static List_t xPendingReadyList;						/*< Tasks that have been readied while the scheduler was suspended.  They will be moved to the ready list when the scheduler is resumed. */
+#if configLTO_HELPER /* << EST */
+  /* If using -lto (Link Time Optimization), the linker might replace/remove the names of the following variables.
+   * If using a FreeRTOS Kernel aware debugger (e.g. Segger FreeRTOS task aware plugin), then the debugger won't be able to see the symbols and will fail.
+   * Therefore (more as of a hack) the symbols are defined with external linkage, even if not used from other modules.
+   * See https://mcuoneclipse.com/2017/07/27/troubleshooting-tips-for-freertos-thread-aware-debugging-in-eclipse/
+   */
+  PRIVILEGED_DATA /*static*/ List_t pxReadyTasksLists[ configMAX_PRIORITIES ];/*< Prioritised ready tasks. */
+  PRIVILEGED_DATA /*static*/ List_t xDelayedTaskList1;            /*< Delayed tasks. */
+  PRIVILEGED_DATA /*static*/ List_t xDelayedTaskList2;            /*< Delayed tasks (two lists are used - one for delays that have overflowed the current tick count. */
+  PRIVILEGED_DATA /*static*/ List_t * volatile pxDelayedTaskList;       /*< Points to the delayed task list currently being used. */
+  PRIVILEGED_DATA /*static*/ List_t * volatile pxOverflowDelayedTaskList;   /*< Points to the delayed task list currently being used to hold tasks that have overflowed the current tick count. */
+  PRIVILEGED_DATA /*static*/ List_t xPendingReadyList;            /*< Tasks that have been readied while the scheduler was suspended.  They will be moved to the ready list when the scheduler is resumed. */
+#else
+  PRIVILEGED_DATA static List_t pxReadyTasksLists[ configMAX_PRIORITIES ];/*< Prioritised ready tasks. */
+  PRIVILEGED_DATA static List_t xDelayedTaskList1;            /*< Delayed tasks. */
+  PRIVILEGED_DATA static List_t xDelayedTaskList2;            /*< Delayed tasks (two lists are used - one for delays that have overflowed the current tick count. */
+  PRIVILEGED_DATA static List_t * volatile pxDelayedTaskList;       /*< Points to the delayed task list currently being used. */
+  PRIVILEGED_DATA static List_t * volatile pxOverflowDelayedTaskList;   /*< Points to the delayed task list currently being used to hold tasks that have overflowed the current tick count. */
+  PRIVILEGED_DATA static List_t xPendingReadyList;            /*< Tasks that have been readied while the scheduler was suspended.  They will be moved to the ready list when the scheduler is resumed. */
+#endif
 
 #if( INCLUDE_vTaskDelete == 1 )
 
@@ -419,15 +433,40 @@ PRIVILEGED_DATA static List_t xPendingReadyList;						/*< Tasks that have been r
 #endif
 
 #if ( INCLUDE_vTaskSuspend == 1 )
-
+#if configLTO_HELPER /* << EST */
+  /* If using -lto (Link Time Optimization), the linker might replace/remove the names of the following variables.
+   * If using a FreeRTOS Kernel aware debugger (e.g. Segger FreeRTOS task aware plugin), then the debugger won't be able to see the symbols and will fail.
+   * Therefore (more as of a hack) the symbols are defined with external linkage, even if not used from other modules.
+   * See https://mcuoneclipse.com/2017/07/27/troubleshooting-tips-for-freertos-thread-aware-debugging-in-eclipse/
+   */
+  PRIVILEGED_DATA /*static*/ List_t xSuspendedTaskList;         /*< Tasks that are currently suspended. */
+#else
 	PRIVILEGED_DATA static List_t xSuspendedTaskList;					/*< Tasks that are currently suspended. */
-
+#endif
 #endif
 
 /* Other file private variables. --------------------------------*/
-PRIVILEGED_DATA static volatile UBaseType_t uxCurrentNumberOfTasks 	= ( UBaseType_t ) 0U;
+#if configLTO_HELPER /* << EST */
+  /* If using -lto (Link Time Optimization), the linker might replace/remove the names of the following variables.
+   * If using a FreeRTOS Kernel aware debugger (e.g. Segger FreeRTOS task aware plugin), then the debugger won't be able to see the symbols and will fail.
+   * Therefore (more as of a hack) the symbols are defined with external linkage, even if not used from other modules.
+   * See https://mcuoneclipse.com/2017/07/27/troubleshooting-tips-for-freertos-thread-aware-debugging-in-eclipse/
+   */
+	PRIVILEGED_DATA /*static*/ volatile UBaseType_t uxCurrentNumberOfTasks 	= ( UBaseType_t ) 0U;
+#else
+  PRIVILEGED_DATA static volatile UBaseType_t uxCurrentNumberOfTasks  = ( UBaseType_t ) 0U;
+#endif
 PRIVILEGED_DATA static volatile TickType_t xTickCount 				= ( TickType_t ) 0U;
-PRIVILEGED_DATA static volatile UBaseType_t uxTopReadyPriority 		= tskIDLE_PRIORITY;
+#if configLTO_HELPER /* << EST */
+  /* If using -lto (Link Time Optimization), the linker might replace/remove the names of the following variables.
+   * If using a FreeRTOS Kernel aware debugger (e.g. Segger FreeRTOS task aware plugin), then the debugger won't be able to see the symbols and will fail.
+   * Therefore (more as of a hack) the symbols are defined with external linkage, even if not used from other modules.
+   * See https://mcuoneclipse.com/2017/07/27/troubleshooting-tips-for-freertos-thread-aware-debugging-in-eclipse/
+   */
+  PRIVILEGED_DATA /*static*/ volatile UBaseType_t uxTopReadyPriority 		= tskIDLE_PRIORITY;
+#else
+  PRIVILEGED_DATA static volatile UBaseType_t uxTopReadyPriority    = tskIDLE_PRIORITY;
+#endif
 PRIVILEGED_DATA static volatile BaseType_t xSchedulerRunning 		= pdFALSE;
 PRIVILEGED_DATA static volatile UBaseType_t uxPendedTicks 			= ( UBaseType_t ) 0U;
 PRIVILEGED_DATA static volatile BaseType_t xYieldPending 			= pdFALSE;

diff --git a/Drivers/sw/FreeRTOS.drv b/Drivers/sw/FreeRTOS.drv
@@ -4763,6 +4763,15 @@ void %vOnPreSleepProcessing(portTickType expectedIdleTicks)
    /*!< 1: enable special GDB stack backtrace debug helper; 0: disabled */
 #endif
 
+#ifndef configLTO_HELPER
+%if defined(EnableLTODebugHelper) & %EnableLTODebugHelper='yes'
+  #define configLTO_HELPER                                       %>50 (1 && configCPU_FAMILY_IS_ARM(configCPU_FAMILY) && (configCOMPILER==configCOMPILER_ARM_GCC))
+%else
+  #define configLTO_HELPER                                       %>50 (0 && configCPU_FAMILY_IS_ARM(configCPU_FAMILY) && (configCOMPILER==configCOMPILER_ARM_GCC))
+%endif
+   /*!< 1: enable special GNU Link Time Optimizer (-lto) debug helper code; 0: disabled */
+#endif
+
 #ifndef configHEAP_SCHEME_IDENTIFICATION
 %if defined(freeRTOSMemorySchemeConstant) & %freeRTOSMemorySchemeConstant='yes'
   #define configHEAP_SCHEME_IDENTIFICATION                       %>50 (1 && configCPU_FAMILY_IS_ARM(configCPU_FAMILY))