irqbypass: Use xarray to track producers and consumers

irqbypass: Use xarray to track producers and consumers

Track IRQ bypass producers and consumers using an xarray to avoid the O(2n)
insertion time associated with walking a list to check for duplicate
entries, and to search for an partner.

At low (tens or few hundreds) total producer/consumer counts, using a list
is faster due to the need to allocate backing storage for xarray.  But as
count creeps into the thousands, xarray wins easily, and can provide
several orders of magnitude better latency at high counts.  E.g. hundreds
of nanoseconds vs. hundreds of milliseconds.

Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: David Matlack <dmatlack@google.com>
Cc: Like Xu <like.xu.linux@gmail.com>
Cc: Binbin Wu <binbin.wu@linux.intel.com>
Reported-by: Yong He <alexyonghe@tencent.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217379
Link: https://lore.kernel.org/all/20230801115646.33990-1-likexu@tencent.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20250516230734.2564775-8-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>