The detailed description of the seven system calls are as follows:


1. rbed_schedule 

SYNOPSIS
	#defined in sched.c
	asmlinkage int sys_rbed_schedule(pid_t id, int p, struct sched_param *param)

DESCRIPTION
	rbed_schedule() sets a new scheduling policy p for process with
pid=id. The scheduling parameters of the process are set according to param.   

RETURN VALUE
	rbed_schedule returns the resource level (non-negative integer)
at which the process can run for its next period and negative value
on error. Each resource level indicates a CPU utilization 
(execution time / period), for example, 0 -> 80%, 1 -> 40%, 2 -> 20%, etc. 


2. rbed_deadline_met 

SYNOPSIS
	#defined in sched.c
	asmlinkage int sys_rbed_deadline_met(pid_t id)

DESCRIPTION
	rbed_deadline_met checks if the process with pid=id meets its deadline 
or not. It gets the current time using the rdtsc register, compare it to 
the deadline of the process. If completion time < deadline, sleep for 
time = deadline - completion_time, else don't sleep and start next
period right away.

RETURN VALUE
	1) The last four (lower four) bits are for qos levels and wrap flag
		0x*0..0x*9  -> 0..9 qos levels
		0x*A        -> wrap
	2) The previous four (upper four) bits are for deadline meet flags.
		0x0* for successfully making the deadline 
		0x1* didn't make it
		0x2* apic break occurred during schedule (usually don't happen)


3. rate_adjust 

SYNOPSIS
	#defined in sched.c
	asmlinkage long sys_rate_adjust(long ctr_err)

DESCRIPTION
	rate_adjust adjusts the rate for the current process according to the 
rescaled benefit by the control error ctr_err. This is designed for adaptive
applications that needs to dynamically adjust their periods according
to the available CPU utilization. 

RETURN VALUE
	rate_adjust returns the current actual period for the current process. 


4. getperiod  

SYNOPSIS
	#defined in sched.c
	asmlinkage long sys_getperiod(int flag)

DESCRIPTION
	getperiod gets the previous actual period or next expected period for 
the current SRT process according to the flag.

RETURN VALUE
	getperiod returns the previous actual period of the current
process if flag=0 and returns the next expected period if the flag=1.


5. setqos 

SYNOPSIS
	#defined in sched.c
	asmlinkage int sys_setqos(int flag){

DESCRIPTION
	setqos sets the adaptive resource allocation policy for the current 
process according to the flag. If flag=0, it sets the policy to "optimal"
policy; if flag=1, it sets the policy to "proportional" policy. The
"optimal" policy allocates all the resources to the process that has 
the maximum control error, which is passed into the kernel by
adjust_adjust system call. The "proportional" policy allocates the
resources to the processes proportionally to their control error.    
 
RETURN VALUE
	setqos returns the old (previous) resource allocation flag, which
indicates "0: optimal" or "1: proportional" 


6. rbed_tracedump 

SYNOPSIS
	#defined in sched.c
	asmlinkage int sys_rbed_tracedump(int *num, struct rbed_trace *tr)

DESCRIPTION
	rbed_tracedump copies the kernel data with size of 
num*sizeof(struct rbed_trace) to user space structure specified by tr.  
This system calls is used for application to get the kernel debug
information. The kernel data is saved in a kernel buffer, which only
keeps the latest data.   

RETURN VALUE
	returns 0 if the kernel data does not overflow, or 1 if the kernel
data overflows. 


7. rbed_rt_tracedump 

SYNOPSIS
	#defined in sched.c
	asmlinkage int sys_rbed_rt_tracedump(int *num, struct rbed_trace *tr)

DESCRIPTION
	Similar to rbed_tracedump, except that it only dumps the data of
real-time processes. 

RETURN VALUE
	returns 0 if the kernel data does not overflow, or 1 if the kernel
data overflows.