move compaction_filter to immutable_options

Summary:
all shared_ptrs are in immutable_options now. This will also make
options assignment a little cheaper

Test Plan: make release

Reviewers: sdong, yhchiang, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23001

Author: Lei Jin

db/db_impl.cc

@@ -2643,12 +2643,12 @@ Status DBImpl::ProcessKeyValueCompaction(
       cfd->user_comparator(), cfd->ioptions()->merge_operator,
       db_options_.info_log.get(), cfd->options()->min_partial_merge_operands,
       false /* internal key corruption is expected */);
-  auto compaction_filter = cfd->options()->compaction_filter;
+  auto compaction_filter = cfd->ioptions()->compaction_filter;
   std::unique_ptr<CompactionFilter> compaction_filter_from_factory = nullptr;
   if (!compaction_filter) {
     auto context = compact->GetFilterContextV1();
     compaction_filter_from_factory =
-        cfd->options()->compaction_filter_factory->CreateCompactionFilter(
+        cfd->ioptions()->compaction_filter_factory->CreateCompactionFilter(
             context);
     compaction_filter = compaction_filter_from_factory.get();
   }
@@ -3085,8 +3085,8 @@ Status DBImpl::DoCompactionWork(CompactionState* compact,
     = nullptr;
   auto context = compact->GetFilterContext();
   compaction_filter_from_factory_v2 =
-      cfd->options()->compaction_filter_factory_v2->CreateCompactionFilterV2(
-          context);
+      cfd->ioptions()->compaction_filter_factory_v2->
+          CreateCompactionFilterV2(context);
   auto compaction_filter_v2 =
     compaction_filter_from_factory_v2.get();
 
@@ -3116,7 +3116,7 @@ Status DBImpl::DoCompactionWork(CompactionState* compact,
         continue;
       } else {
         const SliceTransform* transformer =
-            cfd->options()->compaction_filter_factory_v2->GetPrefixExtractor();
+            cfd->ioptions()->compaction_filter_factory_v2->GetPrefixExtractor();
         const auto key_prefix = transformer->Transform(ikey.user_key);
         if (!prefix_initialized) {
           compact->cur_prefix_ = key_prefix.ToString();

include/rocksdb/immutable_options.h

@@ -13,7 +13,9 @@ namespace rocksdb {
 // ImmutableCFOptions is a data struct used by RocksDB internal. It contains a
 // subset of Options that should not be changed during the entire lifetime
 // of DB. You shouldn't need to access this data structure unless you are
-// implementing a new TableFactory.
+// implementing a new TableFactory. Raw pointers defined in this struct do
+// not have ownership to the data they point to. Options contains shared_ptr
+// to these data.
 struct ImmutableCFOptions {
   explicit ImmutableCFOptions(const Options& options);
 
@@ -27,6 +29,12 @@ struct ImmutableCFOptions {
 
   MergeOperator* merge_operator;
 
+  const CompactionFilter* compaction_filter;
+
+  CompactionFilterFactory* compaction_filter_factory;
+
+  CompactionFilterFactoryV2* compaction_filter_factory_v2;
+
   Logger* info_log;
 
   Statistics* statistics;

util/options.cc

@@ -38,6 +38,9 @@ ImmutableCFOptions::ImmutableCFOptions(const Options& options)
     prefix_extractor(options.prefix_extractor.get()),
     comparator(options.comparator),
     merge_operator(options.merge_operator.get()),
+    compaction_filter(options.compaction_filter),
+    compaction_filter_factory(options.compaction_filter_factory.get()),
+    compaction_filter_factory_v2(options.compaction_filter_factory_v2.get()),
     info_log(options.info_log.get()),
     statistics(options.statistics.get()),
     env(options.env),