I am monitoring PCIe data on an Xeon E5-2600 machine according to the Uncore Performance Monitoring Guide Table 2-15.
I wonder what kind of transactions this is monitoring. I conducted some tests where I generated a lot of MMIO transactions to a PCIe device (using Linux; ioremap a PCIe device's BAR and use the readl/writel instructions), but they do NOT show up for above stated scenario.
I can see these instructions with the OFFCORE_RESPONSE counters, but why there and not by filtering for PCIe packets like in above's scenario? This feels a bit unintuitive.