pub unsafe extern "C" fn uxTaskGetSystemState(
    pxTaskStatusArray: *mut TaskStatus_t,
    uxArraySize: UBaseType_t,
    pulTotalRunTime: *mut u32
) -> UBaseType_t
Expand description

configUSE_TRACE_FACILITY must be defined as 1 in FreeRTOSConfig.h for uxTaskGetSystemState() to be available.

uxTaskGetSystemState() populates an TaskStatus_t structure for each task in the system. TaskStatus_t structures contain, among other things, members for the task handle, task name, task priority, task state, and total amount of run time consumed by the task. See the TaskStatus_t structure definition in this file for the full member list.

@note This function is intended for debugging use only as its use results in the scheduler remaining suspended for an extended period.

@param pxTaskStatusArray A pointer to an array of TaskStatus_t structures. The array must contain at least one TaskStatus_t structure for each task that is under the control of the RTOS. The number of tasks under the control of the RTOS can be determined using the uxTaskGetNumberOfTasks() API function.

@param uxArraySize The size of the array pointed to by the pxTaskStatusArray parameter. The size is specified as the number of indexes in the array, or the number of TaskStatus_t structures contained in the array, not by the number of bytes in the array.

@param pulTotalRunTime If configGENERATE_RUN_TIME_STATS is set to 1 in FreeRTOSConfig.h then *pulTotalRunTime is set by uxTaskGetSystemState() to the total run time (as defined by the run time stats clock, see https://www.FreeRTOS.org/rtos-run-time-stats.html) since the target booted. pulTotalRunTime can be set to NULL to omit the total run time information.

@return The number of TaskStatus_t structures that were populated by uxTaskGetSystemState(). This should equal the number returned by the uxTaskGetNumberOfTasks() API function, but will be zero if the value passed in the uxArraySize parameter was too small.

Example usage: @code{c} // This example demonstrates how a human readable table of run time stats // information is generated from raw data provided by uxTaskGetSystemState(). // The human readable table is written to pcWriteBuffer void vTaskGetRunTimeStats( char *pcWriteBuffer ) { TaskStatus_t *pxTaskStatusArray; volatile UBaseType_t uxArraySize, x; uint32_t ulTotalRunTime, ulStatsAsPercentage;

 // Make sure the write buffer does not contain a string.

*pcWriteBuffer = 0x00;

 // Take a snapshot of the number of tasks in case it changes while this
 // function is executing.
 uxArraySize = uxTaskGetNumberOfTasks();

 // Allocate a TaskStatus_t structure for each task.  An array could be
 // allocated statically at compile time.
 pxTaskStatusArray = pvPortMalloc( uxArraySize * sizeof( TaskStatus_t ) );

 if( pxTaskStatusArray != NULL )
 {
     // Generate raw status information about each task.
     uxArraySize = uxTaskGetSystemState( pxTaskStatusArray, uxArraySize, &ulTotalRunTime );

     // For percentage calculations.
     ulTotalRunTime /= 100UL;

     // Avoid divide by zero errors.
     if( ulTotalRunTime > 0 )
     {
         // For each populated position in the pxTaskStatusArray array,
         // format the raw data as human readable ASCII data
         for( x = 0; x < uxArraySize; x++ )
         {
             // What percentage of the total run time has the task used?
             // This will always be rounded down to the nearest integer.
             // ulTotalRunTimeDiv100 has already been divided by 100.
             ulStatsAsPercentage = pxTaskStatusArray[ x ].ulRunTimeCounter / ulTotalRunTime;

             if( ulStatsAsPercentage > 0UL )
             {
                 sprintf( pcWriteBuffer, "%s\t\t%lu\t\t%lu%%\r\n", pxTaskStatusArray[ x ].pcTaskName, pxTaskStatusArray[ x ].ulRunTimeCounter, ulStatsAsPercentage );
             }
             else
             {
                 // If the percentage is zero here then the task has
                 // consumed less than 1% of the total run time.
                 sprintf( pcWriteBuffer, "%s\t\t%lu\t\t<1%%\r\n", pxTaskStatusArray[ x ].pcTaskName, pxTaskStatusArray[ x ].ulRunTimeCounter );
             }

             pcWriteBuffer += strlen( ( char * ) pcWriteBuffer );
         }
     }

     // The array is no longer needed, free the memory it consumes.
     vPortFree( pxTaskStatusArray );
 }

} @endcode