fixing perf testing for packets w/ packet builder (#252)

Summary:
With some packets in textures moved to packet builder it broke perf testing. So fixing it. Also removing outdated comment about inline decap since you folks decided to run tons of syscalls instead

Pull Request resolved: #252

Reviewed By: pdubovitsky

Differential Revision: D84077259

Pulled By: frankfeir

fbshipit-source-id: 76a8392bbec4170d2f2125a21488eb9130a84db0

Author: tehnerd

katran/lib/testing/framework/BpfTester.cpp

@@ -431,10 +431,15 @@ std::vector<TestResult> BpfTester::testPerfFromFixture(
 
   // Run all tests and collect results
   for (int i = first_index; i < last_index; i++) {
-    auto single_results = runXdpProgPerf(
-        config_.testData[i].inputPacket,
-        config_.testData[i].description,
-        repeat);
+    std::string input_packet;
+    if (config_.testData[i].inputPacketBuilder.has_value()) {
+      auto inputResult = config_.testData[i].inputPacketBuilder->build();
+      input_packet = inputResult.base64Packet;
+    } else {
+      input_packet = config_.testData[i].inputPacket;
+    }
+    auto single_results =
+        runXdpProgPerf(input_packet, config_.testData[i].description, repeat);
     results.insert(results.end(), single_results.begin(), single_results.end());
   }
   return results;
@@ -480,7 +485,7 @@ std::vector<TestResult> BpfTester::runXdpProgPerf(
       duration = 1;
     }
   }
-  if (repeat > 0) {
+  if (repeat > 0 && total_duration > 0) {
     auto avgDuration = total_duration / repeat;
     auto pps = kNanosecInSec / avgDuration;
     auto pps_millions = static_cast<double>(pps) / 1000000.0;

katran/lib/testing/framework/katran_tester.cpp

@@ -398,7 +398,6 @@ int main(int argc, char** argv) {
     tester.testPcktsFromPcap();
     return 0;
   } else if (FLAGS_perf_testing) {
-    // for perf tests to work katran must be compiled w -DINLINE_DECAP
     preparePerfTestingLbData(*lb);
     auto results = tester.testPerfFromFixture(FLAGS_repeat, FLAGS_position);
     printPerfResults(results);