[$] Smarter IRQ suspension in the networking stack

High-performance networking is a highly tuned activity; the amount of timeavailable to deal with each packet may be measured in nanoseconds, so caremust be taken to avoid anything that might slow the process down.Recently, there has been a fair amount of attention given to a patch setmerged for 6.13 that, it is claimed, can improve processing efficiency(and, thus, power savings)in data centers by as much as 30%. The change itself, contributed by JoeDamato and Martin Karsten, is a relatively small tweak to existingoptimization techniques; it shows just how much care is needed to optimizea high-bandwidth server.