/* * Update packet in/out/collision statistics. The i82557 doesn't * allow you to access these counters without doing a fairly * expensive DMA to get _all_ of the statistics it maintains, so * we do this operation here only once per second. The statistics * counters in the kernel are updated from the previous dump-stats * DMA and then a new dump-stats DMA is started. The on-chip * counters are zeroed when the DMA completes. If we can't start * the DMA immediately, we don't wait - we just prepare to read * them again next time. */