RISC-V Design · All levels

CSR Programming Model, Privilege Visibility, and Timer Facilities: Reports and Metrics

Reports and Metrics for CSR Programming Model, Privilege Visibility, and Timer Facilities.

Reports and metrics

Reports and Metrics for CSR Programming Model, Privilege Visibility, and Timer Facilities is anchored on CSR read/write hazard rate, timer interrupt accuracy (ns error), and software context-switch overhead attributable to CSR traffic.. Convert observations into mechanism-backed decisions with explicit ownership.

Before/after trend

diagram

BEFORE / AFTER TREND - CSR Programming Model, Privilege Visibility, and Timer Facilities

CSR read/write hazard rate, timer interrupt accuracy (ns error), and software context-switch overhead attributable to CSR traffic.
  ^
  |                           o target band
  |                    o after fix + reruns
  |             o
  |      o baseline (failing)
  +--------------------------------------------------> iteration
       capture issue      isolate mechanism      close + monitor

Use this view to confirm the gain is causal and stable across seeds.

Root-cause tree

diagram

ROOT CAUSE TREE - CSR Programming Model, Privilege Visibility, and Timer Facilities

CSR read/write hazard rate, timer interrupt accuracy (ns error), and software context-switch overhead attributable to CSR traffic. regressed
          |
   reproducible on fixed seed?
      /                 \
    no                   yes
    |                     |
env/tool drift       first failing domain?
                     /        |         \
                  decode    execute    memory/MMU
                    |         |            |
               control map  bypass/FU   TLB/walk/perm
                    |
         privilege/CSR side effects checked?

Stop at first confirmed mechanism, then assign explicit owner + fix proof.

Track CSR read/write hazard rate, timer interrupt accuracy (ns error), and software context-switch overhead attributable to CSR traffic. on representative workloads, not just microbenchmarks.
Include build/runtime/privilege metadata in report headers.
Pair performance movement with correctness and reliability checks.
Report tail stability, not only mean uplift.

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