## RTEMS 6.1 Release Notes ### RTEMS Improvements In this section, we discuss public API level changes as well as improvements to the implementation of those API routines. Public API changes usually fall into one of the following categories: * Addition of new methods * Modifications to prototypes * Deletion of obsoleted methods Implementation improvements usually fall into one of the following categories: * Algorithm improvements in execution time or memory usage * Critical section reduction ### API Changes * If the processor set is not large enough to contain the processor set of the scheduler, then `rtems_scheduler_get_processor_set()` returns `RTEMS_INVALID_SIZE` instead of `RTEMS_INVALID_NUMBER`. * If the processor set is not large enough to contain the processor affinity set of the task, then `rtems_task_get_affinity()` returns `RTEMS_INVALID_SIZE` instead of `RTEMS_INVALID_NUMBER`. * If time-of-day argument is `NULL`, then `rtems_timer_fire_when()`, `rtems_timer_server_fire_when(), and `rtems_task_wake_when()` return `RTEMS_INVALID_ADDRESS` instead of `RTEMS_INVALID_CLOCK`. * The time-of-day arguments in `rtems_timer_fire_when()`, `rtems_timer_server_fire_when(), and `rtems_task_wake_when()` were constified. * If the entry point is `NULL`, then `rtems_task_start()` returns now `RTEMS_INVALID_ADDRESS`. * If `rtems_task_delete()` is called from within interrupt context, then it returns now `RTEMS_CALLED_FROM_ISR`. * The rate monotonic period statistics are no longer affected by `rtems_cpu_usage_reset()`. * Termios * `txTaskCharsDequeued` has been added to `struct rtems_termios_tty`. With that the size of the structure changed. Libraries and applications that use the structure should be recompiled. * The `l_start` line discipline function now receives the number of characters that have been sent. It is save to ignore the extra parameter for applications that don't need it. #### API Additions * `RTEMS_ALIGN_UP()` * `RTEMS_ALIGN_DOWN()` * `rtems_get_build_label()` * `rtems_get_target_hash()` * `rtems_interrupt_clear()` * `rtems_interrupt_entry_initialize()` * `RTEMS_INTERRUPT_ENTRY_INITIALIZER()` * `rtems_interrupt_entry_install()` * `rtems_interrupt_entry_remove()` * `rtems_interrupt_get_affinity()` * `rtems_interrupt_get_attributes()` * `rtems_interrupt_handler_install()` * `rtems_interrupt_handler_iterate()` * `rtems_interrupt_handler_remove()` * `rtems_interrupt_is_pending()` * `rtems_interrupt_raise()` * `rtems_interrupt_raise_on()` * `rtems_interrupt_server_action_prepend()` * `rtems_interrupt_server_create()` * `rtems_interrupt_server_delete()` * `rtems_interrupt_server_entry_destroy()` * `rtems_interrupt_server_entry_initialize()` * `rtems_interrupt_server_entry_move()` * `rtems_interrupt_server_entry_submit()` * `rtems_interrupt_server_handler_install()` * `rtems_interrupt_server_handler_iterate()` * `rtems_interrupt_server_handler_remove()` * `rtems_interrupt_server_initialize()` * `rtems_interrupt_server_move()` * `rtems_interrupt_server_request_destroy()` * `rtems_interrupt_server_request_initialize()` * `rtems_interrupt_server_request_set_vector()` * `rtems_interrupt_server_request_submit()` * `rtems_interrupt_server_resume()` * `rtems_interrupt_server_set_affinity()` * `rtems_interrupt_server_suspend()` * `rtems_interrupt_set_affinity()` * `rtems_interrupt_vector_disable()` * `rtems_interrupt_vector_enable()` * `rtems_interrupt_vector_is_enabled()` * `RTEMS_MESSAGE_QUEUE_BUFFER()` * `rtems_message_queue_construct()` * `RTEMS_PARTITION_ALIGNMENT` * `rtems_task_construct()` * `RTEMS_TASK_STORAGE_SIZE()` * `RTEMS_TASK_STORAGE_ALIGNMENT` #### API Implementation Improvements * The Classic API signal processing was reworked to avoid possible infinite recursions. It is still strongly recommended to use the `RTEMS_NO_ASR` task mode for the signal handler. * Zero size allocation results are now consistent accross directives, for example `malloc( 0 )` and `posix_memalign( &p, align, 0 )` return now a unique pointer (or `NULL` if the heap is empty). In POSIX, zero size memory allocations are implementation-defined behaviour. The implementation has two options: * https://pubs.opengroup.org/onlinepubs/9699919799/functions/malloc.html * https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_memalign.html Linux and FreeBSD return a unique pointer for zero size memory allocations. This approach is now also used in RTEMS as well throughout the memory allocation directives #### API Deprecations * `rtems_iterate_over_all_threads()`. Use `rtems_task_iterate()` instead. * `_Copyright_Notice` is deprecated. Use `rtems_get_copyright_notice()` instead. * `_RTEMS_version` is deprecated. Use `rtems_get_version_string()` instead. * `RTEMS_COMPILER_NO_RETURN_ATTRIBUTE` is deprecated. Use `RTEMS_NO_RETURN` instead. * `RTEMS_COMPILER_PURE_ATTRIBUTE` is deprecated. Use `RTEMS_PURE` instead. * `RTEMS_COMPILER_DEPRECATED_ATTRIBUTE` is deprecated. Use `RTEMS_DEPRECATED` instead. * `RTEMS_COMPILER_UNUSED_ATTRIBUTE` is deprecated. Use `RTEMS_UNUSED` instead. * `RTEMS_COMPILER_PACKED_ATTRIBUTE` is deprecated. Use `RTEMS_PACKED` instead. #### API Removals * The obsoleted header file was removed. * The never implemented `rtems_interrupt_cause()` directive was removed. * Support for the RTEMS thread model used by GCC versions prior to 6.1 was removed (for example `rtems_gxx_once()`). * The obsoleted `rtems_get_current_processor()` directive was removed. Use `rtems_scheduler_get_processor()` instead. * The obsoleted `rtems_get_processor_count()` directive was removed. Use `rtems_scheduler_get_processor_maximum()` instead. * The obsoleted `boolean` type was removed. Use `bool` instead. * The obsoleted `single_precision` type was removed. Use `float` instead. * The obsoleted `double_precision` type was removed. Use `double` instead. * The obsoleted `proc_ptr` type was removed. Use a proper function pointer type. * The obsoleted `rtems_context` type was removed. * The obsoleted `rtems_context_fp` type was removed. * The obsoleted `rtems_extension` type was removed. Use `void` instead. * The obsoleted `rtems_io_lookup_name()` type was removed. Use `stat()` instead. * The obsoleted `region_information_block` was removed. Use `Heap_Information_block` instead. * The obsoleted `rtems_thread_cpu_usage_t` type was removed. Use `struct timespec` instead. * The obsoleted `rtems_rate_monotonic_period_time_t` type was removed. Use `struct timespec` instead. * The obsoleted `RTEMS_MAXIMUM_NAME_LENGTH` define was removed. Use `sizeof(rtems_name)` instead. ### SMP Support Improvements * The SMP scheduler framework was reworked to fix potential data corruption issues and priority group ordering violations. ### Configuration Changes * TBD * New configuration options: * `CONFIGURE_MAXIMUM_THREAD_LOCAL_STORAGE_SIZE` * `CONFIGURE_MINIMUM_TASKS_WITH_USER_PROVIDED_STORAGE` * Renamed configuration options: * TBD * Removed configuration options: * TBD ## RTEMS Shell Improvements The following improvements were made to the RTEMS Shell: * TBD ## General * TBD ## Architectures Removed obsoleted architectures: * Epiphany * PowerPC SPE Obsoleted architectures: * V850 * SPARC64 * SuperH (sh) ## BSPs and Device Drivers * General * TBD * New BSPs * `arm/fvp` * `arm/imxrt` * `arm/stm32h7` * Significant updates to existing BSPs * `ARCH/BSP`: TBD * Removal of obsoleted BSPs * `powerpc/brs5l` * `powerpc/brs6l` * `powerpc/dp2` * `powerpc/haleakala` * `powerpc/mpc5566evb_spe` * `powerpc/mpc5643l_dpu` * `powerpc/mpc5643l_evb` * `powerpc/mpc5674f_ecu508_app` * `powerpc/mpc5674f_ecu508_boot` * `powerpc/mpc5674fevb_spe` * `powerpc/mpc5674f_rsm6` * Obsoleted BSPs * `m68k/gen68302` * `m68k/ods68302` * `powerpc/mbx8xx` * Drivers * TBD ## Newlib Changes * Add `futimens()` and `utimensat()` ## Ecosystem * Improved GCOV support for RTEMS and embedded systems in general. See GCC options `-fprofile-info-section` and `-fprofile-update=atomic`. The `libgcov` provides now the `__gcov_info_to_gcda()` function to dump the GCOV information.