[PATCH 7/7] rtems: Add rtems_task_build()

[Sebastian Huber]

On 22/08/2020 09:49, Chris Johns wrote:

> On 21/8/20 9:51 pm, Sebastian Huber wrote:
>> In contrast to rtems_task_create() this function creates a task with a
>> user-provided task storage area.
> The name is build but it creates a task? I am wondering about
> rtems_task_create_static or something along this line?

A function to do a static initialization is a contradiction from my 
point of view. Static initialization means for me that you statically 
initialize a data structure and then it is ready to use (it may involve 
a static constructor).

The function builds a task from user-provided (stack, attributes, etc.) 
and system-provided (thread control block) components.

>
>> Close #3959.
> Sorry, I had not read the ticket's details.

There is a similar ticket for message queues:

https://devel.rtems.org/ticket/4007

>
> Chris
>
>> ---
>>   cpukit/Makefile.am                     |   1 +
>>   cpukit/include/rtems/rtems/tasks.h     |  65 ++++++
>>   cpukit/include/rtems/rtems/tasksimpl.h |  11 +
>>   cpukit/rtems/src/taskbuild.c           | 273 ++++++++++++++++++++++++
>>   cpukit/rtems/src/taskcreate.c          | 274 +++++--------------------
>>   testsuites/sptests/sp01/init.c         |  22 +-
>>   testsuites/sptests/sp01/sp01.doc       |   1 +
>>   testsuites/sptests/sp01/system.h       |   2 +-
>>   8 files changed, 413 insertions(+), 236 deletions(-)
>>   create mode 100644 cpukit/rtems/src/taskbuild.c
>>
>> diff --git a/cpukit/Makefile.am b/cpukit/Makefile.am
>> index bc56822cf8..e382478eac 100644
>> --- a/cpukit/Makefile.am
>> +++ b/cpukit/Makefile.am
>> @@ -785,6 +785,7 @@ librtemscpu_a_SOURCES += rtems/src/statustext.c
>>   librtemscpu_a_SOURCES += rtems/src/statustoerrno.c
>>   librtemscpu_a_SOURCES += rtems/src/systemeventreceive.c
>>   librtemscpu_a_SOURCES += rtems/src/systemeventsend.c
>> +librtemscpu_a_SOURCES += rtems/src/taskbuild.c
>>   librtemscpu_a_SOURCES += rtems/src/taskcreate.c
>>   librtemscpu_a_SOURCES += rtems/src/taskdelete.c
>>   librtemscpu_a_SOURCES += rtems/src/taskexit.c
>> diff --git a/cpukit/include/rtems/rtems/tasks.h b/cpukit/include/rtems/rtems/tasks.h
>> index 12c323e60e..dff811686a 100644
>> --- a/cpukit/include/rtems/rtems/tasks.h
>> +++ b/cpukit/include/rtems/rtems/tasks.h
>> @@ -164,6 +164,71 @@ rtems_status_code rtems_task_create(
>> [...]
>> +  /**
>> +   * @brief This member defines the optional handler to free the task storage
>> +   *   area.
>> +   *
>> +   * It may be NULL.
>> +   */
>> +  void ( *storage_free )( void * );
> Called under what context? What can this call do? For example call the standard
> heap allocator.

This is a good question.  What about:

@brief This member defines the optional handler to free the task storage 
area.

It is called when the task building aborts due to a failed task create 
extension or the task is deleted. It is called from task context under 
protection of the object allocator lock. It is allowed to call free() in 
this handler.