Back out "hazptr: Allow destruction of obj batch after default domain"

Summary: Original commit changeset: 6021479ab36c

Reviewed By: d4l3k

Differential Revision: D18535981

fbshipit-source-id: 4f9e5da29ed6d9bae04f29bcf273b41d39cc5754

folly/synchronization/Hazptr-fwd.h

@@ -132,10 +132,6 @@ class hazptr_domain;
 template <template <typename> class Atom = std::atomic>
 hazptr_domain<Atom>& default_hazptr_domain();
 
-/** default_hazptr_domain_alive */
-template <template <typename> class Atom = std::atomic>
-bool& default_hazptr_domain_alive();
-
 /** hazptr_domain_push_list */
 template <template <typename> class Atom = std::atomic>
 void hazptr_domain_push_list(

folly/synchronization/HazptrDomain.h

@@ -133,26 +133,14 @@ class hazptr_domain {
 
  public:
   /** Constructor */
-  hazptr_domain() {
-    if (std::is_same<Atom<int>, std::atomic<int>>{} &&
-        this == &default_hazptr_domain<Atom>()) {
-      set_default_hazptr_domain_alive(true);
-    }
-  }
+  hazptr_domain() = default;
 
   /** Destructor */
   ~hazptr_domain() {
     shutdown_ = true;
     reclaim_all_objects();
     free_hazptr_recs();
-    if (!tagged_.empty()) {
-      auto head = tagged_.pop_all(RetiredList::kDontLock);
-      reclaim_list_transitive(head);
-    }
-    if (std::is_same<Atom<int>, std::atomic<int>>{} &&
-        this == &default_hazptr_domain<Atom>()) {
-      set_default_hazptr_domain_alive(false);
-    }
+    DCHECK(tagged_.empty());
   }
 
   hazptr_domain(const hazptr_domain&) = delete;
@@ -595,10 +583,6 @@ class hazptr_domain {
     hcount_.fetch_add(1);
     return rec;
   }
-
-  void set_default_hazptr_domain_alive(bool b) {
-    default_hazptr_domain_alive<Atom>() = b;
-  }
 }; // hazptr_domain
 
 /**
@@ -627,12 +611,6 @@ FOLLY_ALWAYS_INLINE hazptr_domain<Atom>& default_hazptr_domain() {
   return hazptr_default_domain_helper<Atom>::get();
 }
 
-template <template <typename> class Atom>
-bool& default_hazptr_domain_alive() {
-  static bool alive = false;
-  return alive;
-}
-
 /** hazptr_domain_push_retired: push a list of retired objects into a domain */
 template <template <typename> class Atom>
 void hazptr_domain_push_retired(

folly/synchronization/HazptrObj.h

@@ -331,8 +331,7 @@ class hazptr_obj_batch {
       Obj* obj = l.head();
       reclaim_list(obj);
     }
-    if (pushed_to_domain_tagged_.load(std::memory_order_relaxed) &&
-        default_hazptr_domain_alive<Atom>()) {
+    if (pushed_to_domain_tagged_.load(std::memory_order_relaxed)) {
       default_hazptr_domain<Atom>().cleanup_batch_tag(this);
     }
     DCHECK(l_.empty());
@@ -360,7 +359,7 @@ class hazptr_obj_batch {
 
   /** push_obj */
   void push_obj(Obj* obj) {
-    if (active_ && default_hazptr_domain_alive<Atom>()) {
+    if (active_) {
       l_.push(obj);
       inc_count();
       check_threshold_push();
@@ -385,9 +384,6 @@ class hazptr_obj_batch {
 
   /** check_threshold_push */
   void check_threshold_push() {
-    if (!default_hazptr_domain_alive<Atom>()) {
-      return;
-    }
     auto c = count();
     while (c >= kThreshold) {
       if (cas_count(c, 0)) {