correct level information in version_set.cc (#6920)

Summary:
fix these two issues https://github.com/facebook/rocksdb/issues/6912  and https://github.com/facebook/rocksdb/issues/6667
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6920

Reviewed By: cheng-chang

Differential Revision: D21864885

Pulled By: ajkr

fbshipit-source-id: 10e21fc1851b67a59d44358f59c64fa5523bd263

db/version_set.cc

@@ -1806,11 +1806,11 @@ void Version::Get(const ReadOptions& read_options, const LookupKey& k,
         cfd_->internal_stats()->GetFileReadHist(fp.GetHitFileLevel()),
         IsFilterSkipped(static_cast<int>(fp.GetHitFileLevel()),
                         fp.IsHitFileLastInLevel()),
-        fp.GetCurrentLevel());
+        fp.GetHitFileLevel());
     // TODO: examine the behavior for corrupted key
     if (timer_enabled) {
       PERF_COUNTER_BY_LEVEL_ADD(get_from_table_nanos, timer.ElapsedNanos(),
-                                fp.GetCurrentLevel());
+                                fp.GetHitFileLevel());
     }
     if (!status->ok()) {
       return;
@@ -1946,11 +1946,11 @@ void Version::MultiGet(const ReadOptions& read_options, MultiGetRange* range,
         cfd_->internal_stats()->GetFileReadHist(fp.GetHitFileLevel()),
         IsFilterSkipped(static_cast<int>(fp.GetHitFileLevel()),
                         fp.IsHitFileLastInLevel()),
-        fp.GetCurrentLevel());
+        fp.GetHitFileLevel());
     // TODO: examine the behavior for corrupted key
     if (timer_enabled) {
       PERF_COUNTER_BY_LEVEL_ADD(get_from_table_nanos, timer.ElapsedNanos(),
-                                fp.GetCurrentLevel());
+                                fp.GetHitFileLevel());
     }
     if (!s.ok()) {
       // TODO: Set status for individual keys appropriately
@@ -5672,7 +5672,7 @@ InternalIterator* VersionSet::MakeInputIterator(
               /*table_reader_ptr=*/nullptr,
               /*file_read_hist=*/nullptr, TableReaderCaller::kCompaction,
               /*arena=*/nullptr,
-              /*skip_filters=*/false, /*level=*/static_cast<int>(which),
+              /*skip_filters=*/false, /*level=*/static_cast<int>(c->level(which)),
               /*smallest_compaction_key=*/nullptr,
               /*largest_compaction_key=*/nullptr,
               /*allow_unprepared_value=*/false);
@@ -5686,7 +5686,7 @@ InternalIterator* VersionSet::MakeInputIterator(
             /*should_sample=*/false,
             /*no per level latency histogram=*/nullptr,
             TableReaderCaller::kCompaction, /*skip_filters=*/false,
-            /*level=*/static_cast<int>(which), range_del_agg,
+            /*level=*/static_cast<int>(c->level(which)), range_del_agg,
             c->boundaries(which));
       }
     }