[PATCH]: 1f69b5ee46 FreeRTOS: Always show current execution before scheduler is started

[gerrit]

This is an automated email from Gerrit.

"Frank Dischner <frank.disch...@gmail.com>" just uploaded a new patch set to 
Gerrit, which you can find at https://review.openocd.org/c/openocd/+/6935

-- gerrit

commit 1f69b5ee46393b5ebcca1f228724e225f72c88b9
Author: Frank Dischner <frank.disch...@gmail.com>
Date:   Sun Apr 17 21:24:28 2022 -0500

    FreeRTOS: Always show current execution before scheduler is started
    
    Previously, if the target was halted before the FreeRTOS scheduler was
    started but after at least one thread was created, then the current thread
    would be set to whichever thread had the highest priority. In addition to
    being misleading, because that thread is not actually running, it can
    cause issues with gdb. For instance, breaking somewhere before the first
    thread is created will show the current execution as the current thread,
    but stepping over a line that creates a thread will cause the current
    thread to switch to the newly created thread and the current execution to
    disappear. The sudden disappearance of the current execution thread seems
    to confuse some versions of gdb.
    
    With this change, the value of xSchedulerRunning is checked to determine
    whether the scheduler has been started. If it hasn't, then a fake
    'current execution' thread is always created and made the current thread.
    
    Signed-off-by: Frank Dischner <frank.disch...@gmail.com>
    Change-Id: Ide0fe7d9ffb9fac95cee4c805735f434c7c4934d

diff --git a/src/rtos/FreeRTOS.c b/src/rtos/FreeRTOS.c
index 99a48e0056..93d1b62797 100644
--- a/src/rtos/FreeRTOS.c
+++ b/src/rtos/FreeRTOS.c
@@ -127,6 +127,7 @@ enum freertos_symbol_values {
        FREERTOS_VAL_X_SUSPENDED_TASK_LIST = 8,
        FREERTOS_VAL_UX_CURRENT_NUMBER_OF_TASKS = 9,
        FREERTOS_VAL_UX_TOP_USED_PRIORITY = 10,
+       FREERTOS_VAL_X_SCHEDULER_RUNNING = 11,
 };
 
 struct symbols {
@@ -146,6 +147,7 @@ static const struct symbols freertos_symbol_list[] = {
        { "xSuspendedTaskList", true }, /* Only if INCLUDE_vTaskSuspend */
        { "uxCurrentNumberOfTasks", false },
        { "uxTopUsedPriority", true }, /* Unavailable since v7.5.3 */
+       { "xSchedulerRunning", false },
        { NULL, false }
 };
 
@@ -205,7 +207,20 @@ static int freertos_update_threads(struct rtos *rtos)
                                                                                
rtos->symbols[FREERTOS_VAL_PX_CURRENT_TCB].address,
                                                                                
rtos->current_thread);
 
-       if ((thread_list_size  == 0) || (rtos->current_thread == 0)) {
+       /* read scheduler running */
+       uint32_t scheduler_running;
+       retval = target_read_u32(rtos->target,
+                       rtos->symbols[FREERTOS_VAL_X_SCHEDULER_RUNNING].address,
+                       &scheduler_running);
+       if (retval != ERROR_OK) {
+               LOG_ERROR("Error reading FreeRTOS scheduler state");
+               return retval;
+       }
+       LOG_DEBUG("FreeRTOS: Read xSchedulerRunning at 0x%" PRIx64 ", value 
0x%" PRIx32,
+                                                                               
rtos->symbols[FREERTOS_VAL_X_SCHEDULER_RUNNING].address,
+                                                                               
scheduler_running);
+
+       if ((thread_list_size  == 0) || (rtos->current_thread == 0) || 
(scheduler_running != 1)) {
                /* Either : No RTOS threads - there is always at least the 
current execution though */
                /* OR     : No current thread - all threads suspended - show 
the current execution
                 * of idling */

--