I’m porting several huge libraries from other real-time os'es (VxWorks, WINCE, DSP/BIOS etc.) to Linux. The job includes porting of a glue-layer between Linux and the libraries. This glue-layer is the implementation of: * clock_ms () * int_lock() * int_unlock() * mutex_create() * mutex_give() * task_create() etc. etc. Each function has a different implementation on each real-time os. As an ex. the implementation of mutex_create() for vxworks is like this: SEM_ID id = semMCreate(SEM_Q_PRIORITY | SEM_INVERSION_SAFE | SEM_DELETE_SAFE); while on Linux it is like this: sem_t *semH = (sem_t*)malloc( sizeof(sem_t) ); sem_init(semH, 0,init); return (void*)semH; By using this approach, the libraries can be written independent of OS. But the functions (which I need) that causes problem for me is the following functions: timer_init( callbackFunc ) and timer_set( CLOCK_MS timeMs ) The first function (timer_init) is called at startup of my application, and installs a callbackfuction for all timerevents. The second function is to arm the timer. When the timer goes off, the callbackfuntion should be called preferably on a high priority. Some of the other os'es implements this as a one-shot-timerinterrupt, so the priority should be quite high. My first approach to port this to Linux was to use signals and setitimer(). This worked, but the problem with this solution was that the priority of the callback was the same as the priority of the thread that set up the timer. My next approach was to use a special high priority timer thread. Whenever a lo-pri thread needs to arm the timer, it signals the high-pri thread to set up the alarm. I have not tested this yet so I don't know how well it will work. But does other have other solutions/suggestions how to solve this? br. Morten - To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
