Restoretpl() - Intel Extensible Firmware Interface Specification

3.1.8

RestoreTPL()

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