DPL: Extending initial parsing of input messages

This is in preparation for support of split payloads with pruned headers

Author: matthiasrichter

Framework/Core/src/DataProcessingDevice.cxx

@@ -886,63 +886,86 @@ void DataProcessingDevice::handleData(DataProcessorContext& context, InputChanne
     SourceInfo
   };
 
+  struct InputInfo {
+    InputInfo(size_t p, size_t s, InputType t)
+      : position(p), size(s), type(t)
+    {
+    }
+    size_t position;
+    size_t size;
+    InputType type;
+  };
+
   // This is how we validate inputs. I.e. we try to enforce the O2 Data model
   // and we do a few stats. We bind parts as a lambda captured variable, rather
   // than an input, because we do not want the outer loop actually be exposed
   // to the implementation details of the messaging layer.
   auto getInputTypes = [&stats = context.registry->get<DataProcessingStats>(),
-                        &info, &context]() -> std::optional<std::vector<InputType>> {
+                        &info, &context]() -> std::optional<std::vector<InputInfo>> {
     auto& parts = info.parts;
     stats.inputParts = parts.Size();
 
     TracyPlot("messages received", (int64_t)parts.Size());
-    if (parts.Size() % 2) {
-      return std::nullopt;
-    }
-    std::vector<InputType> results(parts.Size() / 2, InputType::Invalid);
+    std::vector<InputInfo> results;
+    // we can reserve the upper limit
+    results.reserve(parts.Size() / 2);
+    size_t nTotalPayloads = 0;
+
+    auto insertInputInfo = [&results, &nTotalPayloads](size_t position, size_t length, InputType type) {
+      results.emplace_back(position, length, type);
+      if (type != InputType::Invalid && length > 1) {
+        nTotalPayloads += length - 1;
+      }
+    };
 
-    for (size_t hi = 0; hi < parts.Size() / 2; ++hi) {
-      auto pi = hi * 2;
+    for (size_t pi = 0; pi < parts.Size(); pi += 2) {
       auto sih = o2::header::get<SourceInfoHeader*>(parts.At(pi)->GetData());
       if (sih) {
         info.state = sih->state;
-        results[hi] = InputType::SourceInfo;
+        insertInputInfo(pi, 2, InputType::SourceInfo);
         *context.wasActive = true;
         continue;
       }
       auto dh = o2::header::get<DataHeader*>(parts.At(pi)->GetData());
       if (!dh) {
-        results[hi] = InputType::Invalid;
+        insertInputInfo(pi, 0, InputType::Invalid);
         LOGP(error, "Header is not a DataHeader?");
         continue;
       }
       if (dh->payloadSize != parts.At(pi + 1)->GetSize()) {
-        results[hi] = InputType::Invalid;
+        insertInputInfo(pi, 0, InputType::Invalid);
         LOGP(error, "DataHeader payloadSize mismatch");
         continue;
       }
       TracyPlot("payload size", (int64_t)dh->payloadSize);
       auto dph = o2::header::get<DataProcessingHeader*>(parts.At(pi)->GetData());
       TracyAlloc(parts.At(pi + 1)->GetData(), parts.At(pi + 1)->GetSize());
       if (!dph) {
-        results[hi] = InputType::Invalid;
+        insertInputInfo(pi, 2, InputType::Invalid);
         LOGP(error, "Header stack does not contain DataProcessingHeader");
         continue;
       }
-      // We can set the type for the next splitPayloadParts
-      // because we are guaranteed they are all the same.
-      // If splitPayloadParts = 0, we assume that means there is only one (header, payload)
-      // pair.
-      size_t finalSplitPayloadIndex = hi + (dh->splitPayloadParts > 0 ? dh->splitPayloadParts : 1);
-      if (finalSplitPayloadIndex > results.size()) {
-        LOGP(error, "DataHeader::splitPayloadParts invalid");
-        results[hi] = InputType::Invalid;
-        continue;
-      }
-      for (; hi < finalSplitPayloadIndex; ++hi) {
-        results[hi] = InputType::Data;
+      {
+        // We can set the type for the next splitPayloadParts
+        // because we are guaranteed they are all the same.
+        // If splitPayloadParts = 0, we assume that means there is only one (header, payload)
+        // pair.
+        size_t finalSplitPayloadIndex = pi + (dh->splitPayloadParts > 0 ? dh->splitPayloadParts : 1) * 2;
+        if (finalSplitPayloadIndex > parts.Size()) {
+          LOGP(error, "DataHeader::splitPayloadParts invalid");
+          insertInputInfo(pi, 0, InputType::Invalid);
+          continue;
+        }
+        insertInputInfo(pi, 2, InputType::Data);
+        for (; pi + 2 < finalSplitPayloadIndex; pi += 2) {
+          insertInputInfo(pi + 2, 2, InputType::Data);
+        }
       }
-      hi = finalSplitPayloadIndex - 1;
+    }
+    assert(std::accumulate(results.begin(), results.end(), 0, [](size_t const& count, auto const& element) -> size_t { return count + element.size; }));
+    if (results.size() + nTotalPayloads != parts.Size()) {
+      LOG(ERROR) << "inconsistent number of inputs extracted";
+      return std::nullopt;
     }
     return results;
   };
@@ -951,21 +974,22 @@ void DataProcessingDevice::handleData(DataProcessorContext& context, InputChanne
     registry.get<DataProcessingStats>().errorCount++;
   };
 
-  auto handleValidMessages = [&info, &context = context, &relayer = *context.relayer, &reportError](std::vector<InputType> const& types) {
+  auto handleValidMessages = [&info, &context = context, &relayer = *context.relayer, &reportError](std::vector<InputInfo> const& inputInfos) {
     static WaitBackpressurePolicy policy;
     auto& parts = info.parts;
     // We relay execution to make sure we have a complete set of parts
     // available.
-    for (size_t pi = 0; pi < (parts.Size() / 2); ++pi) {
-      switch (types[pi]) {
+    for (auto ii = 0; ii < inputInfos.size(); ++ii) {
+      auto const& input = inputInfos[ii];
+      switch (input.type) {
         case InputType::Data: {
-          auto headerIndex = 2 * pi;
-          auto payloadIndex = 2 * pi + 1;
+          auto headerIndex = input.position;
+          auto payloadIndex = headerIndex + 1;
           assert(payloadIndex < parts.Size());
           auto dh = o2::header::get<DataHeader*>(parts.At(headerIndex)->GetData());
           auto relayed = relayer.relay(parts.At(headerIndex),
                                        &parts.At(payloadIndex), dh->splitPayloadParts > 0 ? dh->splitPayloadParts * 2 - 1 : 0);
-          pi += dh->splitPayloadParts > 0 ? dh->splitPayloadParts - 1 : 0;
+          ii += dh->splitPayloadParts > 0 ? dh->splitPayloadParts - 1 : 0;
           switch (relayed) {
             case DataRelayer::Backpressured:
               if (info.normalOpsNotified == true && info.backpressureNotified == false) {
@@ -988,8 +1012,8 @@ void DataProcessingDevice::handleData(DataProcessorContext& context, InputChanne
         } break;
         case InputType::SourceInfo: {
           *context.wasActive = true;
-          auto headerIndex = 2 * pi;
-          auto payloadIndex = 2 * pi + 1;
+          auto headerIndex = input.position;
+          auto payloadIndex = input.position + 1;
           assert(payloadIndex < parts.Size());
           auto dh = o2::header::get<DataHeader*>(parts.At(headerIndex)->GetData());
           // FIXME: the message with the end of stream cannot contain