camerad: stress test (#34735)

* refactor a bunch of stuff

* prob

* enable

* rm print

* cleanup

---------

Co-authored-by: Comma Device <device@comma.ai>

system/camerad/cameras/spectra.h

@@ -211,9 +211,9 @@ private:
   inline static bool first_frame_synced = false;
 
   // a mode for stressing edge cases: realignment, sync failures, etc.
-  inline bool stress_test(const char* log, float prob=0.02) {
-    static bool enable = getenv("SPECTRA_STRESS_TEST") != nullptr;
-    bool triggered = enable && ((static_cast<double>(rand()) / RAND_MAX) < prob);
+  inline bool stress_test(const char* log) {
+    static double prob = std::stod(util::getenv("SPECTRA_ERROR_PROB", "-1"));;
+    bool triggered = (prob > 0) && ((static_cast<double>(rand()) / RAND_MAX) < prob);
     if (triggered) {
       LOGE("stress test (cam %d): %s", cc.camera_num, log);
     }

system/camerad/test/test_camerad.py

@@ -83,13 +83,12 @@ class TestCamerad:
       assert np.all((ts[c]['timestampEof'] - ts[c]['timestampSof']) > 0)
 
       # logMonoTime > SOF
-      assert np.all((ts[c]['t'] - ts[c]['timestampSof']/1e9) > 0.001)
-      assert np.all((ts[c]['t'] - ts[c]['timestampEof']/1e9) > 0.001)
+      assert np.all((ts[c]['t'] - ts[c]['timestampSof']/1e9) > 1e-7)
+      assert np.all((ts[c]['t'] - ts[c]['timestampEof']/1e9) > 1e-7)
 
-  @pytest.mark.skip("TODO: enable this")
   def test_stress_test(self):
-    os.environ['SPECTRA_STRESS_TEST'] = '1'
-    logs = run_and_log(["camerad", ], CAMERAS, 15)
+    os.environ['SPECTRA_ERROR_PROB'] = '0.008'
+    logs = run_and_log(["camerad", ], CAMERAS, 10)
     ts = msgs_to_time_series(logs)
 
     # we should see some jumps from introduced errors