[PATCH 07/16] posix: Make POSIX API aware of scheduler instances

[Gedare Bloom]

On Fri, Jun 17, 2016 at 6:51 AM, Sebastian Huber
<sebastian.huber at embedded-brains.de> wrote:
> ---
>  cpukit/posix/include/rtems/posix/priorityimpl.h | 82 ++++++++++---------------
>  cpukit/posix/src/mutexgetprioceiling.c          |  1 +
>  cpukit/posix/src/mutexinit.c                    |  5 +-
>  cpukit/posix/src/mutexsetprioceiling.c          | 35 +++++++----
>  cpukit/posix/src/psxpriorityisvalid.c           |  8 +--
>  cpukit/posix/src/pthread.c                      |  4 +-
>  cpukit/posix/src/pthreadcreate.c                | 11 ++--
>  cpukit/posix/src/pthreadgetschedparam.c         | 11 +++-
>  cpukit/posix/src/pthreadsetschedparam.c         | 11 ++--
>  cpukit/posix/src/pthreadsetschedprio.c          |  7 ++-
>  10 files changed, 94 insertions(+), 81 deletions(-)
>
> diff --git a/cpukit/posix/include/rtems/posix/priorityimpl.h b/cpukit/posix/include/rtems/posix/priorityimpl.h
> index e3f23e7..7e770f7 100644
> --- a/cpukit/posix/include/rtems/posix/priorityimpl.h
> +++ b/cpukit/posix/include/rtems/posix/priorityimpl.h
> @@ -30,29 +30,10 @@ extern "C" {
>   *
>   * @ingroup POSIXAPI
>   *
> - * @brief Interface to the POSIX Priority Implementation
> - *
> - */
> -/**@{**/
> -
> -/**
> - * 1003.1b-1993,2.2.2.80 definition of priority, p. 19
> - *
> - * "Numerically higher values represent higher priorities."
> - *
> - * Thus, RTEMS Core has priorities run in the opposite sense of the POSIX API.
> - *
> - * There are only 254 posix priority levels since a task at priority level
> - * 255 would never run because of the RTEMS idle task.  This is necessary
> - * because GNAT maps the lowest Ada task priority to the lowest thread
> - * priority.  The lowest priority Ada task should get to run, so there is
> - * a fundamental conflict with having 255 priorities.
> + * @brief Interface to the POSIX Priority Implementation.
>   *
> - * But since RTEMS can be configured with fewer than 256 priorities,
> - * we use the internal constant.
> + * @{
>   */
> -#define POSIX_SCHEDULER_MAXIMUM_PRIORITY (PRIORITY_MAXIMUM - 1)
> -
>
>  /**
>   *  This is the numerically least important POSIX priority.
> @@ -72,53 +53,58 @@ int _POSIX_Priority_Get_maximum( const Scheduler_Control *scheduler );
>  /**
>   * @brief Check if POSIX priority is valid.
>   *
> - * 1003.1b-1993,2.2.2.80 definition of priority, p. 19
> - *
> - * "Numerically higher values represent higher priorities."
> - *
> - * Thus, RTEMS Core has priorities run in the opposite sense of the POSIX API.
> - *
> - * @param[in] priority is the priority to test
> - *
> - * @retval TRUE The priority is valid.
> - * @retval FALSE The priority is invalid.
> + * According to POSIX, numerically higher values represent higher priorities.
> + * Thus, SuperCore has priorities run in the opposite sense of the POSIX API.
> + *
> + * Let N be the maximum priority of this scheduler instance.   The SuperCore
> + * priority zero is system reserved (PRIORITY_PSEUDO_ISR).  There are only
> + * N - 1 POSIX API priority levels since a thread at SuperCore priority N would
> + * never run because of the idle threads.  This is necessary because GNAT maps
> + * the lowest Ada task priority to the lowest thread priority.  The lowest
> + * priority Ada task should get to run, so there is a fundamental conflict with
> + * having N priorities.
> + *
> + * @param[in] scheduler The scheduler instance.
> + * @param[in] priority The POSIX API priority to test.
> + *
> + * @retval true The priority is valid.
> + * @retval false Otherwise.
>   */
>  bool _POSIX_Priority_Is_valid(
> -  int priority
> +  const Scheduler_Control *scheduler,
> +  int                      priority
>  );
>
>  /**
> - * @brief Convert POSIX priority to SuperCore priority.
> - *
> - * This method converts a POSIX API priority into onto the corresponding
> - * SuperCore value.
> + * @brief Converts POSIX priority to SuperCore priority.
>   *
> - * @param[in] priority is the POSIX API priority.
> + * @param[in] scheduler The scheduler instance.
> + * @param[in] priority The POSIX API priority.
>   *
> - * @return This method returns the corresponding SuperCore priority.
> + * @return Returns the corresponding SuperCore priority.
>   */
>  RTEMS_INLINE_ROUTINE Priority_Control _POSIX_Priority_To_core(
> -  int priority
> +  const Scheduler_Control *scheduler,
> +  int                      priority
>  )
>  {
> -  return (Priority_Control) (POSIX_SCHEDULER_MAXIMUM_PRIORITY - priority + 1);
> +  return scheduler->maximum_priority - (Priority_Control) priority;
>  }
>
>  /**
> - * @brief Convert SuperCore priority To POSIX priority.
> - *
> - * This method converts a SuperCore priority into onto the corresponding
> - * POSIX API value.
> + * @brief Converts SuperCore priority to POSIX priority.
>   *
> - * @param[in] priority is the POSIX API priority.
> + * @param[in] scheduler The scheduler instance.
> + * @param[in] priority The SuperCore priority.
>   *
> - * @return This method returns the corresponding POSIX priority.
> + * @return Returns the corresponding POSIX API priority.
>   */
>  RTEMS_INLINE_ROUTINE int _POSIX_Priority_From_core(
> -  Priority_Control priority
> +  const Scheduler_Control *scheduler,
> +  Priority_Control         priority
>  )
>  {
> -  return (POSIX_SCHEDULER_MAXIMUM_PRIORITY - priority + 1);
> +  return (int) ( scheduler->maximum_priority - priority );
>  }
>
>  /** @} */
> diff --git a/cpukit/posix/src/mutexgetprioceiling.c b/cpukit/posix/src/mutexgetprioceiling.c
> index 2df4776..eda02cb 100644
> --- a/cpukit/posix/src/mutexgetprioceiling.c
> +++ b/cpukit/posix/src/mutexgetprioceiling.c
> @@ -46,6 +46,7 @@ int pthread_mutex_getprioceiling(
>    _POSIX_Mutex_Acquire_critical( the_mutex, &queue_context );
>
>    *prioceiling = _POSIX_Priority_From_core(
> +    &_Scheduler_Table[ 0 ],
Why not _Scheduler_Get_own(executing)? Does it matter which scheduler
control is used.


> @@ -56,13 +52,26 @@ int pthread_mutex_setprioceiling(
>    the_mutex = _POSIX_Mutex_Get_no_protection( mutex );
>    _Assert( the_mutex != NULL );
>
> +  scheduler = &_Scheduler_Table[ 0 ];
> +
ditto.

-Gedare