Add bounded nRF radio yield experiment and correlated worst-hop timings

test/test_nrf_radio_yield_budget.py

@@ -0,0 +1,110 @@
+"""Execute finite per-frame radio yield budgets and default-off behavior."""
+from pathlib import Path
+import os
+import subprocess
+import tempfile
+import unittest
+
+from test_rak3401_buffered_radio_hal import MOCK_HAL
+
+ROOT = Path(__file__).resolve().parents[1]
+
+MOCK = MOCK_HAL.replace('virtual ~ArduinoHal() = default;', '''
+  unsigned yields = 0;
+  virtual ~ArduinoHal() = default;
+  virtual void yield() { ++yields; }
+''')
+
+FIXTURE = r'''
+#include <helpers/radiolib/Nrf52BufferedRadioHal.h>
+int main() {
+  SPIClass bus;
+  Nrf52BufferedRadioHal concrete(bus,8000000);
+  ArduinoHal& radio=concrete;
+  constexpr unsigned budget=MC_NRF_RADIO_BUSY_SPIN_POLLS;
+#if MC_NRF_RADIO_BUSY_SPIN_POLLS == 0
+  static_assert(sizeof(Nrf52BufferedRadioHal)==sizeof(ArduinoHal),"default RAM growth");
+#endif
+  // The first pre-transfer wait delegates immediately, even in opt-in builds.
+  for(unsigned i=0;i<1000;++i) radio.yield();
+  assert(radio.yields==1000 && bus.bursts==0);
+  radio.spiTransfer(nullptr,0,nullptr);
+  radio.yield();
+  assert(radio.yields==1001 && bus.bursts==0);
+
+  uint8_t tx[]={0x86,0x12,0x34},rx[3]={};
+  for(unsigned frame=0;frame<1000;++frame) {
+    const unsigned before=radio.yields;
+    radio.spiTransfer(tx,sizeof(tx),rx);
+    assert(rx[0]==uint8_t(tx[0]^0xa5) && rx[2]==uint8_t(tx[2]^0xa5));
+    for(unsigned i=0;i<budget;++i) radio.yield();
+    assert(radio.yields==before);
+    radio.yield(); assert(radio.yields==before+1);
+    // A zero-byte call must not replenish an exhausted budget.
+    radio.spiTransfer(nullptr,0,nullptr);
+    radio.yield(); assert(radio.yields==before+2);
+  }
+  assert(bus.bursts==1000 && bus.bytes==0);
+
+  // Neither a zero-size transfer midway through a budget nor later ordinary
+  // waits can turn the finite budget into perpetual spinning.
+  unsigned before=radio.yields;
+  radio.spiTransfer(tx,sizeof(tx),rx);
+  for(unsigned i=0;i<budget/2;++i) radio.yield();
+  radio.spiTransfer(nullptr,0,nullptr);
+  for(unsigned i=budget/2;i<budget;++i) radio.yield();
+  assert(radio.yields==before);
+  for(unsigned i=0;i<100000;++i) radio.yield();
+  assert(radio.yields==before+100000);
+  before=radio.yields;
+  radio.spiTransfer(tx,sizeof(tx),rx);
+  for(unsigned i=0;i<100000;++i) radio.yield();
+  assert(radio.yields==before+100000-budget);
+  assert(bus.bursts==1002 && bus.bytes==0);
+}
+'''
+
+
+class NrfRadioYieldBudgetTest(unittest.TestCase):
+    def test_zero_four_eight_sixteen_preserve_transfer_and_bound_skipped_yields(self):
+        with tempfile.TemporaryDirectory() as directory:
+            folder=Path(directory)
+            (folder/'hal/Arduino').mkdir(parents=True)
+            (folder/'hal/Arduino/ArduinoHal.h').write_text(MOCK,encoding='ascii')
+            cpp,binary=folder/'test.cpp',folder/'test.exe'
+            cpp.write_text(FIXTURE,encoding='ascii')
+            for budget in (0,4,8,16):
+                with self.subTest(budget=budget):
+                    built=subprocess.run([os.environ.get('CXX','g++'),'-std=c++17',
+                        '-Wall','-Wextra','-Werror',f'-DMC_NRF_RADIO_BUSY_SPIN_POLLS={budget}',
+                        '-I',str(folder),'-I',str(ROOT/'src'),str(cpp),'-o',str(binary)],
+                        capture_output=True,text=True)
+                    self.assertEqual(built.returncode,0,built.stderr)
+                    ran=subprocess.run([str(binary)],capture_output=True,text=True)
+                    self.assertEqual(ran.returncode,0,ran.stderr)
+            for budget in (-1,17):
+                with self.subTest(invalid_budget=budget):
+                    built=subprocess.run([os.environ.get('CXX','g++'),'-std=c++17',
+                        f'-DMC_NRF_RADIO_BUSY_SPIN_POLLS={budget}','-I',str(folder),
+                        '-I',str(ROOT/'src'),str(cpp),'-o',str(binary)],
+                        capture_output=True,text=True)
+                    self.assertNotEqual(built.returncode,0)
+                    self.assertIn('bounded 0..16 poll budget',built.stderr)
+
+    def test_default_preprocessing_omits_budget_and_override(self):
+        with tempfile.TemporaryDirectory() as directory:
+            folder=Path(directory)
+            (folder/'hal/Arduino').mkdir(parents=True)
+            (folder/'hal/Arduino/ArduinoHal.h').write_text(MOCK,encoding='ascii')
+            result=subprocess.run([os.environ.get('CXX','g++'),'-std=c++17','-E','-P',
+                '-x','c++','-I',str(folder),'-I',str(ROOT/'src'),'-'],
+                input='#include <helpers/radiolib/Nrf52BufferedRadioHal.h>\n',
+                capture_output=True,text=True)
+            self.assertEqual(result.returncode,0,result.stderr)
+            production=result.stdout.split('class Nrf52BufferedRadioHal',1)[1]
+            self.assertNotIn('_busy_spin_polls_remaining',production)
+            self.assertNotIn('void yield()',production)
+
+
+if __name__=='__main__':
+    unittest.main()

test/test_profile_switch_timing.py

@@ -48,7 +48,7 @@ void dwt_enable() { clockEnabled=true; ++enableCalls; }
 int main() {
   using namespace mesh::profiletiming;
   auto& capture=mesh_hil_profile_timing;
-  assert(capture.magic==Magic && capture.size_bytes==1736);
+  assert(capture.magic==Magic && capture.version==2 && capture.size_bytes==1808);
   assert(capture.clock_hz==64000000 && capture.sequence==0);
   initializeClock();
   assert(enableCalls==1 && capture.clock_state==2);
@@ -68,6 +68,7 @@ int main() {
   const auto& forward=capture.direction[0];
   assert(forward.successes==1 && forward.busy==0 && forward.failures==0);
   assert(forward.last_mask==511 && forward.last_us[Whole]==600);
+  assert(forward.worst_us[Whole]==600 && forward.worst_us[Frequency]==50);
   assert(forward.stage[Whole].sum_low_us==600 && forward.stage[Whole].sum_high_us==0);
   assert(forward.stage[Whole].min_us==600 && forward.stage[Whole].max_us==600);
   assert(forward.stage[Whole].histogram[9]==1);
@@ -94,10 +95,13 @@ int main() {
   begin(0,1,0); mark(Frequency,20*64); finish(Success,20*64);
   assert(sum.sum_low_us==9 && sum.sum_high_us==4);
   assert(sum.min_us==20 && sum.max_us==50 && sum.count==2);
+  assert(forward.worst_us[Whole]==600 && forward.worst_us[Frequency]==50);
   begin(1,0,0); mark(Frequency,960*64); finish(Success,960*64);
   assert(capture.direction[1].stage[Frequency].histogram[15]==1);
   begin(1,0,0); mark(Frequency,10000*64); finish(Success,10000*64);
   assert(capture.direction[1].stage[Frequency].histogram[15]==2);
+  assert(capture.direction[1].worst_us[Whole]==10000);
+  assert(capture.direction[1].worst_us[Frequency]==10000);
 }
 '''.replace("@GLOBALS@", self.production_globals()))