A data processing system 2 supporting interrupt handling is provided with
an interrupt controller 24. The interrupt controller is responsive to
save state data when interrupt processing is commenced by pre-emption of
existing processing, whether that be background processing or another
interrupt. If a further interrupt is required to be executed immediately
after the interrupt which triggered the pre-emption, then the speed with
which interrupt processing can be started is advantageously increased if
that subsequent interrupt processing is performed without restoring and
then resaving the original state data. The interrupts in this arrangement
can be considered to be chained together without intervening save and
restore operations.