US 12,475,048 B2
Linefill delegation in a cache hierarchy
Natalya Bondarenko, Antibes (FR); Stefano Ghiggini, Antibes (FR); Kamil Garifullin, Nice (FR); Fabian Gruber, Birmingham (GB); Abhishek Raja, Niagara Falls, NY (US); and Devin S Lafford, Austin, TX (US)
Assigned to Arm Limited, Cambridge (GB)
Filed by Arm Limited, Cambridge (GB)
Filed on Jul. 11, 2023, as Appl. No. 18/350,217.
Prior Publication US 2025/0021480 A1, Jan. 16, 2025
Int. Cl. G06F 12/0811 (2016.01); G06F 12/0862 (2016.01); G06F 12/0871 (2016.01)
CPC G06F 12/0811 (2013.01) [G06F 12/0862 (2013.01); G06F 12/0871 (2013.01)] 20 Claims
OG exemplary drawing
 
1. Apparatus comprising:
a level N cache level; and
a level M cache level, where M is greater than N,
wherein the level N cache level comprises a cache storage and a plurality of linefill slots and the level N cache level is configured to perform a slot allocation procedure in response to a lookup miss in the cache storage, in dependence on a linefill slot occupancy criterion, wherein the slot allocation procedure comprises allocation of an available linefill slot of the plurality of linefill slots to a pending linefill request generated in response to the lookup miss,
wherein on completion of the pending linefill request, the linefill slot allocated to the pending linefill request is configured to provide a cache line within the cache storage to store data returned by the linefill request,
wherein the linefill slot allocated to the pending linefill request is freed upon completion of the pending linefill request,
wherein the level N cache level is configured to effect a modification of the slot allocation procedure in dependence on the linefill slot occupancy criterion,
and wherein the level N cache level is responsive to the linefill slot occupancy criterion being fulfilled to cause a linefill delegation action to be instructed to the level M cache level.