Fix ios compile

Summary: No __thread for ios.

Test Plan: compile works for ios now

Reviewers: ljin, dhruba

Reviewed By: dhruba

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D22491

db/db_impl.cc

@@ -1979,7 +1979,7 @@ void DBImpl::MaybeScheduleFlushOrCompaction() {
 }
 
 void DBImpl::RecordFlushIOStats() {
-  RecordTick(stats_, FLUSH_WRITE_BYTES, iostats_context.bytes_written);
+  RecordTick(stats_, FLUSH_WRITE_BYTES, IOSTATS(bytes_written));
   IOSTATS_RESET(bytes_written);
 }
 

db/db_impl_readonly.h

@@ -74,6 +74,8 @@ class DBImplReadOnly : public DBImpl {
                               uint32_t target_path_id = 0) override {
     return Status::NotSupported("Not supported operation in read only mode.");
   }
+
+#ifndef ROCKSDB_LITE
   virtual Status DisableFileDeletions() override {
     return Status::NotSupported("Not supported operation in read only mode.");
   }
@@ -85,6 +87,8 @@ class DBImplReadOnly : public DBImpl {
                               bool flush_memtable = true) override {
     return Status::NotSupported("Not supported operation in read only mode.");
   }
+#endif  // ROCKSDB_LITE
+
   using DBImpl::Flush;
   virtual Status Flush(const FlushOptions& options,
                        ColumnFamilyHandle* column_family) override {

include/rocksdb/iostats_context.h

@@ -27,7 +27,9 @@ struct IOStatsContext {
   uint64_t bytes_read;
 };
 
+#ifndef IOS_CROSS_COMPILE
 extern __thread IOStatsContext iostats_context;
+#endif  // IOS_CROSS_COMPILE
 
 }  // namespace rocksdb
 

util/iostats_context.cc

@@ -9,7 +9,9 @@
 
 namespace rocksdb {
 
+#ifndef IOS_CROSS_COMPILE
 __thread IOStatsContext iostats_context;
+#endif  // IOS_CROSS_COMPILE
 
 void IOStatsContext::Reset() {
   thread_pool_id = Env::Priority::TOTAL;

util/iostats_context_imp.h

@@ -6,6 +6,8 @@
 #pragma once
 #include "rocksdb/iostats_context.h"
 
+#ifndef IOS_CROSS_COMPILE
+
 // increment a specific counter by the specified value
 #define IOSTATS_ADD(metric, value)     \
   (iostats_context.metric += value)
@@ -30,3 +32,15 @@
 
 #define IOSTATS(metric)                        \
   (iostats_context.metric)
+
+#else  // IOS_CROSS_COMPILE
+
+#define IOSTATS_ADD(metric, value)
+#define IOSTATS_ADD_IF_POSITIVE(metric, value)
+#define IOSTATS_RESET(metric)
+#define IOSTATS_RESET_ALL()
+#define IOSTATS_SET_THREAD_POOL_ID(value)
+#define IOSTATS_THREAD_POOL_ID()
+#define IOSTATS(metric) 0
+
+#endif  // IOS_CROSS_COMPILE