US 12,332,801 B2
Descriptor cache eviction for multi-queue direct memory access
Chandrasekhar S. Thyamagondlu, Saratoga, CA (US); and Tao Yu, Campbell, CA (US)
Assigned to Xilinx, Inc., San Jose, CA (US)
Filed by Xilinx, Inc., San Jose, CA (US)
Filed on Mar. 28, 2023, as Appl. No. 18/191,326.
Prior Publication US 2024/0330191 A1, Oct. 3, 2024
Int. Cl. G06F 12/08 (2016.01); G06F 12/0891 (2016.01)
CPC G06F 12/0891 (2013.01) [G06F 2212/27 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method, of evicting queues from a memory of a direct memory access system, the method, comprising:
monitoring a global eviction timer configured to count down from a predetermined value responsive to a prior eviction event of a cache memory;
from a plurality of descriptor lists stored in a plurality of entries of a cache memory, determining a set of candidate descriptor lists including one or more descriptor lists of a plurality of descriptor lists in the cache memory in a prefetch only state;
detecting an eviction event by detecting expiration of the global eviction timer and one or more eviction conditions, wherein the expiration of the global eviction timer indicates passage of a minimum amount of time since the prior eviction event;
in response to detecting the eviction event, selecting a descriptor list from the set of candidate descriptor lists for eviction; and
evicting the selected descriptor list from the cache memory.