Add Blacksmith mactop diagnostics

Author: anupsv

.github/scripts/probe-mactop.sh

@@ -0,0 +1,68 @@
+#!/usr/bin/env bash
+# Diagnose whether a macOS runner exposes mactop/IOReport counters.
+set -euo pipefail
+
+seconds="${MLXFAST_MACTOP_PROBE_SECONDS:-3}"
+interval_ms="${MLXFAST_MACTOP_PROBE_INTERVAL_MS:-100}"
+
+if ! command -v mactop >/dev/null 2>&1; then
+  if ! command -v brew >/dev/null 2>&1; then
+    echo "probe-mactop: Homebrew is required to install mactop" >&2
+    exit 1
+  fi
+  echo "probe-mactop: installing mactop"
+  brew install mactop
+fi
+
+mactop_bin="$(command -v mactop)"
+echo "probe-mactop: mactop=${mactop_bin}"
+echo "probe-mactop: user=$(id)"
+echo "probe-mactop: sw_vers"
+sw_vers || true
+echo "probe-mactop: uname=$(uname -a)"
+echo "probe-mactop: cpu=$(sysctl -n machdep.cpu.brand_string 2>/dev/null || true)"
+
+run_mactop_probe() {
+  local label="$1"
+  shift
+  local stdout_path
+  local stderr_path
+  local status
+  stdout_path="$(mktemp "${TMPDIR:-/tmp}/mlxfast-mactop-${label}.out.XXXXXX")"
+  stderr_path="$(mktemp "${TMPDIR:-/tmp}/mlxfast-mactop-${label}.err.XXXXXX")"
+
+  echo "probe-mactop: ${label} start command=$*"
+  set +e
+  "$@" --headless --interval "${interval_ms}" --format json >"${stdout_path}" 2>"${stderr_path}" &
+  local pid="$!"
+  sleep "${seconds}"
+  if kill -0 "${pid}" 2>/dev/null; then
+    kill "${pid}" 2>/dev/null
+  fi
+  wait "${pid}"
+  status="$?"
+  set -e
+
+  echo "probe-mactop: ${label} status=${status}"
+  echo "probe-mactop: ${label} stdout_bytes=$(wc -c < "${stdout_path}" | tr -d ' ')"
+  echo "probe-mactop: ${label} stderr_bytes=$(wc -c < "${stderr_path}" | tr -d ' ')"
+  echo "probe-mactop: ${label} stdout_head"
+  sed -n '1,5p' "${stdout_path}" || true
+  echo "probe-mactop: ${label} stderr"
+  cat "${stderr_path}" || true
+}
+
+run_mactop_probe "plain" "${mactop_bin}"
+
+if sudo -n true 2>/dev/null; then
+  run_mactop_probe "sudo" sudo -n "${mactop_bin}"
+else
+  echo "probe-mactop: sudo passwordless unavailable"
+fi
+
+if command -v sandbox-exec >/dev/null 2>&1 && [[ -f tools/deny-network.sb ]]; then
+  run_mactop_probe "deny-network-sandbox" sandbox-exec -f tools/deny-network.sb "${mactop_bin}"
+else
+  echo "probe-mactop: sandbox-exec or tools/deny-network.sb unavailable"
+fi
+

.github/workflows/mactop-diagnostics.yml

@@ -0,0 +1,19 @@
+name: mactop-diagnostics
+
+on:
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  probe:
+    runs-on: blacksmith-12vcpu-macos-26
+    timeout-minutes: 15
+    steps:
+      - uses: actions/checkout@93cb6efe18208431cddfb8368fd83d5badbf9bfd # v5
+        with:
+          persist-credentials: false
+
+      - name: Probe mactop
+        run: .github/scripts/probe-mactop.sh