Rename pending_compaction_ to queued_for_compaction_.

Summary:
We use `queued_for_flush_` to indicate a column family has been added to the
flush queue. Similarly and to be consistent in our naming, we need to use `queued_for_compaction_` to indicate a column family has been added to the compaction queue. In the past we used
`pending_compaction_` which can also be ambiguous.
Closes https://github.com/facebook/rocksdb/pull/3781

Differential Revision: D7790063

Pulled By: riversand963

fbshipit-source-id: 6786b11a4fcaea36dc9b4672233dbe042f921804

db/column_family.cc

@@ -428,7 +428,7 @@ ColumnFamilyData::ColumnFamilyData(
       flush_reason_(FlushReason::kOthers),
       column_family_set_(column_family_set),
       queued_for_flush_(false),
-      pending_compaction_(false),
+      queued_for_compaction_(false),
       prev_compaction_needed_bytes_(0),
       allow_2pc_(db_options.allow_2pc),
       last_memtable_id_(0) {
@@ -505,7 +505,7 @@ ColumnFamilyData::~ColumnFamilyData() {
   // It would be wrong if this ColumnFamilyData is in flush_queue_ or
   // compaction_queue_ and we destroyed it
   assert(!queued_for_flush_);
-  assert(!pending_compaction_);
+  assert(!queued_for_compaction_);
 
   if (super_version_ != nullptr) {
     // Release SuperVersion reference kept in ThreadLocalPtr.

db/column_family.h

@@ -346,9 +346,9 @@ class ColumnFamilyData {
 
   // Protected by DB mutex
   void set_queued_for_flush(bool value) { queued_for_flush_ = value; }
-  void set_pending_compaction(bool value) { pending_compaction_ = value; }
+  void set_queued_for_compaction(bool value) { queued_for_compaction_ = value; }
   bool queued_for_flush() { return queued_for_flush_; }
-  bool pending_compaction() { return pending_compaction_; }
+  bool queued_for_compaction() { return queued_for_compaction_; }
 
   enum class WriteStallCause {
     kNone,
@@ -457,7 +457,7 @@ class ColumnFamilyData {
 
   // If true --> this ColumnFamily is currently present in
   // DBImpl::compaction_queue_
-  bool pending_compaction_;
+  bool queued_for_compaction_;
 
   uint64_t prev_compaction_needed_bytes_;
 

db/db_impl_compaction_flush.cc

@@ -1272,18 +1272,18 @@ DBImpl::BGJobLimits DBImpl::GetBGJobLimits(int max_background_flushes,
 }
 
 void DBImpl::AddToCompactionQueue(ColumnFamilyData* cfd) {
-  assert(!cfd->pending_compaction());
+  assert(!cfd->queued_for_compaction());
   cfd->Ref();
   compaction_queue_.push_back(cfd);
-  cfd->set_pending_compaction(true);
+  cfd->set_queued_for_compaction(true);
 }
 
 ColumnFamilyData* DBImpl::PopFirstFromCompactionQueue() {
   assert(!compaction_queue_.empty());
   auto cfd = *compaction_queue_.begin();
   compaction_queue_.pop_front();
-  assert(cfd->pending_compaction());
-  cfd->set_pending_compaction(false);
+  assert(cfd->queued_for_compaction());
+  cfd->set_queued_for_compaction(false);
   return cfd;
 }
 
@@ -1314,7 +1314,7 @@ void DBImpl::SchedulePendingFlush(ColumnFamilyData* cfd,
 }
 
 void DBImpl::SchedulePendingCompaction(ColumnFamilyData* cfd) {
-  if (!cfd->pending_compaction() && cfd->NeedsCompaction()) {
+  if (!cfd->queued_for_compaction() && cfd->NeedsCompaction()) {
     AddToCompactionQueue(cfd);
     ++unscheduled_compactions_;
   }