Change Log

Changes for v2.00:

1. UTIME support for interval timers and the poll system call
   NOTE: A huge thanks goes out to Anders Blomdell for providing these features and testing/bugfixing UTIME.
2. Real-time processes can now have unique names assigned to them. The new get_rt_id_from_name system call will return the real-time id associated with a particular named real-time process.
3. To support the naming extension and the new watchdog timers, a new scheduling interface has been developed. For examples of how these new features work, look at the example programs in the user_programs directory of the KURT 2.0 distribution.

Changes for v1.23:

1. Updated to include changes from UTIME v1.17

Changes for v1.21:

1. The prototype for get_rtmod_num has been added to rt.h
2. Another error in the parbit RTMod has been corrected

Changes for v1.19:

1. A new library call was added. This call (get_rtmod_num) takes in the name of the RTMod and returns the RTMod ID of that module.
2. Corrected an error in the parbit RTMod which used to cause a segfault.

Changes for v1.18:

1. Made sure that the retval from copy_xx_user is checked properly
2. Fixed a bug in unregister_rtproc
3. Added a new periodic_process_mode which stores information whether an explicit schedule file was used or periodic processes were being scheduled
4. Corrected logic of rt_suspend, switch_to_normal and unregister_rtproc to handle periodic_process_mode correctly
5. The set_period and get_period system call has been removed.
6. rt_params no longer has the is_periodic flag. If period is set its a periodic process.
7. RT_PERIODIC_PROCESS option has been removed. Now periodic processes are self scheduled.
8. Priorities are now inherited via forking.
9. set_rtparams is allowed only for the super user. This was a bug in the previous version
10. The first call to rt_suspend does not block for a second now. Now the p process is scheduled in 1 jiffy later.
11. The two real-time modes are #defined as SCHED_ALL_PROCS and SCHED_KURT_PROCS
12. rt_suspend now takes a flag (instead of the force parameter earlier) Flags can be SUSPEND_IF_NRT, START_SCHED and STOP_SCHED. SUSPEND_IF_NRT and START_SCHED can be orred with each other.

Changes for v1.17:

• Now the SCHED_KURT policy is a bit mask. If you mark a process as SCHED_KURT, then the 7th bit (highest bit of the lowest byte) is set. This allows processes to be scheduled according to their original policy when the kernel is in non-real-time mode.
• Now switch_to_rt takes an extra parameter which specifies the real_time_mode. If rt_mode is set to 2 then all processes are allowed to run. If rt_mode is set to 1 then only SCHED_KURT processes are allowed to run.
• This version of KURT is with UTIME v1.16 which fixes a bug in the select system call.
• In this version of KURT, no modifications are necessary to /usr/include/sched.h. So, if you have installed any previous version of KURT then edit /usr/include/sched.h and remove the following lines:

  #include <linux/rt.h>

  #define SCHED_KURT 99

• rt.h has been modified so that you can use KURT with C++ programs.

Changes for v1.15:

• Patch is for Linux-2.1.75.
• Patch is available with UTIME-v1.15 patch which is more stable than the earlier releases.
• Periodic processes now schedule themselves (and hence dont need a separate executive process).
• rtd.conf has been modified to include a few more important processes.