Split EventBaseThread from ScopedEventBaseThread

Summary:
[Folly] Split `EventBaseThread` from `ScopedEventBaseThread`.

Now `ScopedEventBaseThread` is really scoped and immovable, while `EventBaseThread` is movable and can be started and stopped.

Users which will never move, and will never start or stop, the `ScopedEventBaseThread` can continue using it. Users which need to move, or which need to start and stop, the object will use `EventBaseThread` instead.

Reviewed By: andriigrynenko

Differential Revision: D4338447

fbshipit-source-id: 57c186630bc199a7a7b7223b1fcb077ce3d86743

mcrouter/CarbonRouterInstanceBase.h

@@ -13,7 +13,7 @@
 #include <memory>
 #include <unordered_map>
 
-#include <folly/io/async/ScopedEventBaseThread.h>
+#include <folly/io/async/EventBaseThread.h>
 
 #include "mcrouter/ConfigApi.h"
 #include "mcrouter/LeaseTokenMap.h"
@@ -142,7 +142,7 @@ class CarbonRouterInstanceBase {
   const std::unique_ptr<AsyncWriter> asyncWriter_;
 
   // Auxiliary EventBase thread.
-  folly::ScopedEventBaseThread evbAuxiliaryThread_;
+  folly::EventBaseThread evbAuxiliaryThread_;
 
   LogPostprocessCallbackFunc postprocessCallback_;
 

mcrouter/LeaseTokenMap.cpp

@@ -25,7 +25,7 @@ inline uint64_t applyMagic(uint32_t id) {
 
 } // anonymous
 
-LeaseTokenMap::LeaseTokenMap(folly::ScopedEventBaseThread& evbThread,
+LeaseTokenMap::LeaseTokenMap(folly::EventBaseThread& evbThread,
                              uint32_t leaseTokenTtl)
     : evbThread_(evbThread),
       timeoutHandler_(*this, *evbThread.getEventBase()),

mcrouter/LeaseTokenMap.h

@@ -16,7 +16,7 @@
 
 #include <folly/IntrusiveList.h>
 #include <folly/io/async/EventBase.h>
-#include <folly/io/async/ScopedEventBaseThread.h>
+#include <folly/io/async/EventBaseThread.h>
 #include <folly/Optional.h>
 #include <folly/Range.h>
 
@@ -43,7 +43,7 @@ class LeaseTokenMap {
    * @param leaseTokenTtl     How many milliseconds the lease token will live.
    *                          Must be greater than 0.
    */
-  explicit LeaseTokenMap(folly::ScopedEventBaseThread& evbThread,
+  explicit LeaseTokenMap(folly::EventBaseThread& evbThread,
                          uint32_t leaseTokenTtl = 10000);
   ~LeaseTokenMap();
 
@@ -144,7 +144,7 @@ class LeaseTokenMap {
    private:
     LeaseTokenMap& parent_;
   };
-  folly::ScopedEventBaseThread& evbThread_;
+  folly::EventBaseThread& evbThread_;
   TimeoutHandler timeoutHandler_;
   uint32_t leaseTokenTtlMs_;
 

mcrouter/lib/network/AsyncMcServer.cpp

@@ -335,8 +335,7 @@ AsyncMcServer::AsyncMcServer(Options opts)
     : opts_(std::move(opts)) {
   if (opts_.congestionController.cpuControlTarget > 0 ||
       opts_.congestionController.memControlTarget > 0) {
-    auxiliaryEvbThread_ =
-        folly::make_unique<folly::ScopedEventBaseThread>(true /* auto start */);
+    auxiliaryEvbThread_ = folly::make_unique<folly::ScopedEventBaseThread>();
 
     if (opts_.congestionController.cpuControlTarget > 0) {
       opts_.worker.cpuController = std::make_shared<CpuController>(

mcrouter/test/cpp_unit_tests/LeaseTokenMapTest.cpp

@@ -15,7 +15,7 @@
 #include <gtest/gtest.h>
 
 #include <folly/io/async/EventBase.h>
-#include <folly/io/async/ScopedEventBaseThread.h>
+#include <folly/io/async/EventBaseThread.h>
 #include <folly/Optional.h>
 
 #include "mcrouter/LeaseTokenMap.h"
@@ -41,7 +41,7 @@ void assertQueryFalse(LeaseTokenMap& map, std::string routeName,
 } // anonymous namespace
 
 TEST(LeaseTokenMap, sanity) {
-  folly::ScopedEventBaseThread evbAuxThread;
+  folly::EventBaseThread evbAuxThread;
   LeaseTokenMap map(evbAuxThread);
 
   EXPECT_EQ(map.size(), 0);
@@ -67,7 +67,7 @@ TEST(LeaseTokenMap, magicConflict) {
   // by memcached) that contains our "magic", LeaseTokenMap should handle it
   // gracefully.
 
-  folly::ScopedEventBaseThread evbAuxThread;
+  folly::EventBaseThread evbAuxThread;
   LeaseTokenMap map(evbAuxThread);
 
   EXPECT_EQ(map.size(), 0);
@@ -85,7 +85,7 @@ TEST(LeaseTokenMap, nestedRoutes) {
   // Simulates the following routing:
   // proxyRoute -> failover:route02 -> failover:route01 -> destinationRoute
 
-  folly::ScopedEventBaseThread evbAuxThread;
+  folly::EventBaseThread evbAuxThread;
   LeaseTokenMap map(evbAuxThread);
 
   // LEASE-GET
@@ -107,7 +107,7 @@ TEST(LeaseTokenMap, nestedRoutes) {
 
 TEST(LeaseTokenMap, shrink) {
   size_t tokenTtl = 100;
-  folly::ScopedEventBaseThread evbAuxThread;
+  folly::EventBaseThread evbAuxThread;
   LeaseTokenMap map(evbAuxThread, tokenTtl);
 
   EXPECT_EQ(map.size(), 0);
@@ -125,7 +125,7 @@ TEST(LeaseTokenMap, shrink) {
 
 TEST(LeaseTokenMap, stress) {
   size_t tokenTtl = 1000;
-  folly::ScopedEventBaseThread evbAuxThread;
+  folly::EventBaseThread evbAuxThread;
   LeaseTokenMap map(evbAuxThread, tokenTtl);
 
   EXPECT_EQ(map.size(), 0);