i#5843 scheduler: Add query of input workload (#6246)

Adds a new stream API get_input_workload_ordinal() which allows the
output stream to figure out which workload its current input stream came
from.

Adds a couple of sanity tests.

Issue: #5843

clients/drcachesim/scheduler/scheduler.cpp

@@ -1169,6 +1169,17 @@ scheduler_tmpl_t<RecordType, ReaderType>::get_input_ordinal(output_ordinal_t out
     return outputs_[output].cur_input;
 }
 
+template <typename RecordType, typename ReaderType>
+int
+scheduler_tmpl_t<RecordType, ReaderType>::get_workload_ordinal(output_ordinal_t output)
+{
+    if (output < 0 || output >= static_cast<output_ordinal_t>(outputs_.size()))
+        return -1;
+    if (outputs_[output].cur_input < 0)
+        return -1;
+    return inputs_[outputs_[output].cur_input].workload;
+}
+
 template <typename RecordType, typename ReaderType>
 bool
 scheduler_tmpl_t<RecordType, ReaderType>::is_record_synthetic(output_ordinal_t output)

clients/drcachesim/scheduler/scheduler.h

@@ -626,6 +626,18 @@ template <typename RecordType, typename ReaderType> class scheduler_tmpl_t {
         {
             return scheduler_->get_input_ordinal(ordinal_);
         }
+        /**
+         * Returns the ordinal for the workload which is the source of the current input
+         * stream feeding this output stream.  This workload ordinal is the index into the
+         * vector of type #dynamorio::drmemtrace::scheduler_tmpl_t::input_workload_t
+         * passed to init().  Returns -1 if there is no current input for this output
+         * stream.
+         */
+        virtual int
+        get_input_workload_ordinal()
+        {
+            return scheduler_->get_workload_ordinal(ordinal_);
+        }
         /**
          * Returns the value of the most recently seen #TRACE_MARKER_TYPE_TIMESTAMP
          * marker.
@@ -1080,6 +1092,11 @@ template <typename RecordType, typename ReaderType> class scheduler_tmpl_t {
     input_ordinal_t
     get_input_ordinal(output_ordinal_t output);
 
+    // Returns the workload ordinal value for the current input stream scheduled on
+    // the 'output_ordinal'-th output stream.
+    int
+    get_workload_ordinal(output_ordinal_t output);
+
     // Returns whether the current record for the current input stream scheduled on
     // the 'output_ordinal'-th output stream is synthetic.
     bool

clients/drcachesim/tests/scheduler_unit_tests.cpp

@@ -298,6 +298,8 @@ test_serial()
     for (scheduler_t::stream_status_t status = stream->next_record(memref);
          status != scheduler_t::STATUS_EOF; status = stream->next_record(memref)) {
         assert(status == scheduler_t::STATUS_OK);
+        // There is just one workload so we expect to always see 0 as the ordinal.
+        assert(stream->get_input_workload_ordinal() == 0);
         if (memref.marker.type == TRACE_TYPE_MARKER &&
             memref.marker.marker_type == TRACE_MARKER_TYPE_TIMESTAMP) {
             assert(memref.marker.marker_value > last_timestamp);
@@ -784,6 +786,7 @@ test_real_file_queries_and_filters(const char *testdir)
         assert(false);
     auto *stream = scheduler.get_stream(0);
     memref_t memref;
+    int max_workload_index = 0;
     int max_input_index = 0;
     std::set<memref_tid_t> tids_seen;
     for (scheduler_t::stream_status_t status = stream->next_record(memref);
@@ -792,10 +795,17 @@ test_real_file_queries_and_filters(const char *testdir)
         assert(memref.instr.tid == TID_1_A || memref.instr.tid == TID_2_A ||
                memref.instr.tid == TID_2_B);
         tids_seen.insert(memref.instr.tid);
+        if (stream->get_input_workload_ordinal() > max_workload_index)
+            max_workload_index = stream->get_input_workload_ordinal();
         if (stream->get_input_stream_ordinal() > max_input_index)
             max_input_index = stream->get_input_stream_ordinal();
+        if (stream->get_input_stream_ordinal() == 0)
+            assert(stream->get_input_workload_ordinal() == 0);
+        else
+            assert(stream->get_input_workload_ordinal() == 1);
     }
-    // Ensure 3 input streams and test input queries.
+    // Ensure 2 input workloads with 3 streams with proper names.
+    assert(max_workload_index == 1);
     assert(max_input_index == 2);
     assert(scheduler.get_input_stream_count() == 3);
     assert(scheduler.get_input_stream_name(0) ==