When compiled without 'options RSS', the ena driver created taskqueues
using taskqueue_start_threads_cpuset passing a mask value of NULL,
both in the ena_setup_tx_resources path (for enqueues) and in the
ena_create_io_queues path (for the completion-processing).
In the default configuration, on most EC2 instances, this results in
taskqueues running in the right NUMA domain, but only by accident; in
non-default configurations (e.g. with with multiple EBS volumes
attached and associated NVMe taskqueues) the taskqueues may land in
the wrong NUMA domain even on instance types where the one-EBS-one-ENA
case produces the desired results.
Set (struct ena_que)->domain and use that to inform the choice of CPU
sets. On a c8gn.48xlarge EC2 instance this doubles throughput on a
32-TCP-stream benchmark.
MFC after: 7 days
Sponsored by: Amazon