The calculation formula of topdown L1 is from the document:
https://urldefense.com/v3/__https://documentation-service.arm.com/static/60250c7395978b529036da86?token=__;!!ACWV5N9M2RV99hQ!Ll-Jgvfs0LitTCU-hC6i6BKBVJfhke-pbQq2VoO-gmuSAcglQ3ZqMVMd2r0An_5a3ZDPYmn8zXuCrpUbehwnLHplVQ$
However, due to the wrong count of stall_slot and stall_slot_frontend
in neoverse-n2, the real stall_slot and real stall_slot_frontend need
to subtract cpu_cycles, so when calculating the topdownL1 metrics,
stall_slot and stall_slot_frontend are corrected.
Since neoverse-n2 does not yet support topdown L2, metricgroups such
as Cache, TLB, Branch, InstructionsMix, and PEutilization will be
added to further analysis of performance bottlenecks in the following
patches.