Changeset 10127:70bd9d295117
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mem: Track DRAM read/write switching and add hysteresis

This patch adds stats for tracking the number of reads/writes per bus
turn around, and also adds hysteresis to the write-to-read switching
to ensure that the queue does not oscilate around the low threshold.

All regressions pass after stats update.

Will go in with the other DRAM patches.