Services
Version 1.02 12/12/00 41
3.1.8 RestoreTPL()
Summary
Restores a task’s priority level to its previous value.
Prototype
VOID
RestoreTPL (
IN EFI_TPL OldTpl
)
Parameters
OldTpl The previous task priority level to restore (the value from a previous,
matching call to RaiseTPL()). Type EFI_TPL is defined in
Section 3.1.7.
Description
The RestoreTPL() function restores a task’s priority level to its previous value. Calls to
RestoreTPL() are matched with calls to RaiseTPL().
Note: If OldTpl is above the current TPL level, then the system behavior is indeterminate.
Additionally, only TPL_APPLICATION, TPL_CALLBACK, TPL_NOTIFY, and
TPL_HIGH_LEVEL may be used. All other values are reserved for use by the firmware; using
them will result in unpredictable behavior. Good codeing practice dictates that all code should
execute at its lowest possible TPL level, and the use of TPL levels above TPL_APPLICATION
must be minimized. Executing at TPL levels above TPL_APPLICATION for extended periods of
time may also result in unpredictable behavior.
Status Codes Returned
None.