I want to understand the working of posted interrupts , have a couple of questions:
- /proc/interrupts have entries for PIN and PIW – My current set up has the a Altera FPGA card in a Virtual Machine generating 1000 interrupts, and I observe that PIN is around 25-40 on various cores. What does the PIN signify?
- Can you please explain what PIN and PIW represent for?
- The perf kvm event - kvm_pi_irte_update , I assume it gets updated when the VT-d assigned device inserts the driver and confirms the posting , there has to be a count for trace event. In my case kvm_pi_irte_update is always zero . Can someone explain its working ad when the counters is updated.
- Is there a way to confirm that the posting occurs?