Description

The Schedule Creator key conveys the authority to create and modify processor reserves. Its holder is able to alter the scheduling attributes of any process, and is necessarily part of the trusted computing base.

A more complete discussion of the EROS scheduling mechanism can be found on the Scheduling page of the concepts section.

The schedule creator key is not rescindable.

Operations

Check Alleged Key Type (OC = KT)

Returns the alleged type of the key.

Reply

R1

AKT_SchedCre: Key is a schedule creator key

Get Max Reserve (OC = 1)

Returns the number of kernel reserve structures.

Reply	W	The number of reserves supported by this kernel image. Reserves 0..15 are assumed to correspond to processes having no capacity reserve running at priorities 0 through 15 respectively.
Result	RC_OK	Success. The returned offset is the offset of the object within the range.

Get Reserve Information (OC = 3)

Retrieves the active and inactive priorities for this schedule.

Request	W	The reserve to be fetched.
Reply	W	The index of the reserve.
	L	The period of this reserve, in milliseconds.
	L	The duration of this reserve, in milliseconds.
	L	The scheduling quanta of this reserve, in milliseconds.
	L	The start time for this reserve, in milliseconds.
	I	The priority under which threads should run when this reserve is active.
	I	The priority under which threads should run when this reserve is inactive.
Result	RC_OK	Success. The returned record contains information concerning this reserve.
	RC_RequestError	The specified reserve index exceeded the number of reserves supported by this kernel.

Set Reserve Information (OC = 4)

Sets the active and inactive priorities for this schedule.

Request	W	The index of the reserve to be modified.
	L	The period of this reserve, in milliseconds.
	L	The duration of this reserve, in milliseconds.
	L	The scheduling quanta of this reserve, in milliseconds.
	L	The start time for this reserve, in milliseconds.
	I	The priority under which threads should run when this reserve is active.
	I	The priority under which threads should run when this reserve is inactive.
Result	RC_OK	Success. The provided values have been set. The reserve is deactivated.
	RC_RequestError	The specified reserve index exceeded the number of reserves supported by this kernel, or corresponded to a strict priority reserve, or the specified active priority was less than 16.