GSOC:disable newlibc reentrancy

[Joel Sherrill]

Alan Cudmore wrote:
> The announcement below may be of interest to the TinyRTEMS project.
> An RTEMS API compatible RTOS. It is currently targeted to the Leon 2,
> but it should be possible to port it to new architectures. The
> announcement says it will be released under GPL this year.
>   
I want to comment on a couple of points in this.

+ 7KB memory footprint probably is just kernel
    services in minimum usage -- not everything
    and not a BSP.  RTEMS proper is not far from that.
   
+ Test coverage.  The test coverage on the CVS head
    is on the order of 97-98% for all the code in
    score, posix, rtems, and sapi using the tests in
    CVS.  This was verified on tsim/erc32.  If you want
    100% binary coverage, it is just a matter of pursuing
    those last cases.

+ Many of the "features" sound like things in
    RTEMS presented in marketing speak.  A few
    sound like it has been tailored to the LEON.

The rest is interesting in that it shows a "profile"
that we could meet with standard source with
a prebuilt cpukit. 

--joel
> Alan
>
> ------------
>
>
> Austrian Aerospace announces the opening of the sources of ARTOS,
> a light weight Real Time Operating System Kernel, for Leon-2.
>
> The API of this free RTOS is compatible to RTEMS (www.rtems.org)
> and exhibits a number of qualities that make it especially
> suitable for space applications:
>
>    - there is no use of dynamic memory allocation
>    - task stack usage and interrupt stack usage can be
>      monitored on-the-fly
>    - detection of implausible values of the stack pointer
>    - detection of task control block damages
>    - heavy use of source code comments to ease
>      long life maintenance
>    - heavy use of assert()ions and defensive programming
>      style
>    - adherence to a locking discipline to ease thorough
>      testing for data races with tools based on the
>      lock set algorithm
>    - independence of the Standard-C library
>    - ARTOS is programmed according to a very
>      strict coding standard
>    - only 7KB memory footprint
>
> This operating system is for single CPU use only and at
> the time being features two different scheduling
> strategies:
>
>    - priority based pre-emtive scheduling, where each task
>      has a unique priority
>    - priority based Run To Completion scheduling
>
> Both schedulers allow to interface with our dynamic Worst
> Case Execution Time measurement tool.
>
> The kernel is configurable/scalable via ten well documented
> preprocessor macros. The ARTOS test suite features 100%
> unit test decision coverage, 100% structured integration
> test coverage and 100% system level requirements coverage
> tested on the AT697E for a given configuration. The test suite
> sources, however, won't be released to the general public.
>
> The RTOS allows the use of Leon-2's Interrupt Mask and
> Priority Register (ITMP) to dynamically change the
> priorities of interrupts or to mask interrupts. The
> implementation of this feature works around the
> unpredictable effect latency of writes to ITMP.
>
> The following RTEMS system calls are supported by ARTOS:
>
> rtems_initialize_executive_early
> rtems_initialize_executive_late
> rtems_set_error_handler
> rtems_fatal_error_occurred
>
> rtems_task_create
> rtems_task_start
> rtems_task_ident
>
> rtems_semaphore_create
> rtems_semaphore_ident
> rtems_semaphore_release
> rtems_semaphore_obtain
>
> rtems_message_queue_create
> rtems_message_queue_ident
> rtems_message_queue_urgent
> rtems_message_queue_send
> rtems_message_queue_get_number_pending
> rtems_message_queue_receive
>
> rtems_event_send
> rtems_event_receive
>
> rtems_interrupt_enable
> rtems_interrupt_disable
> rtems_interrupt_is_in_progress
> rtems_interrupt_catch
>
> rtems_partition_create
> rtems_partition_ident
> rtems_partition_get_buffer
> rtems_partition_return_buffer
>
> The source code of ARTOS will be released under the GPL
> mid of this year. Companies signing a non-disclosure
> agreement with Austrian Aerospace, will have the
> opportunity to obtain test versions of ARTOS earlier
> than that.
>
> In case of questions or requests you are welcomed to
> contact stephan.gruenfelder at space.at
>
>
>
>
>   


-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel.sherrill at OARcorp.com        On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
   Support Available             (256) 722-9985