use C++ atomic with proper default constructor

commit_hash:1c25da3ce2125ca4d8d1e3e026ef0d2a6d0aa355

1 files changed, 14 insertions, 10 deletions

diff --git a/library/cpp/lwtrace/rwspinlock.h b/library/cpp/lwtrace/rwspinlock.h
index 5e4608e068..1effd5fe0e 100644
--- a/library/cpp/lwtrace/rwspinlock.h
+++ b/library/cpp/lwtrace/rwspinlock.h
@@ -1,6 +1,6 @@
 #pragma once
 
-#include <library/cpp/deprecated/atomic/atomic.h>
+#include <atomic>
 
 #include <util/system/spinlock.h>
 
@@ -27,16 +27,16 @@
 //    * writer can release lock (State = 0: -> READING)
 
 struct TRWSpinLock {
-    TAtomic State; // must be initialized by 'TRWSpinLock myLock = {0};' construction
+    std::atomic_signed_lock_free State;
 
     void Init() noexcept {
-        State = 0;
+        State.store(0, std::memory_order_relaxed);
     }
 
     void AcquireRead() noexcept {
         while (true) {
-            TAtomic a = AtomicGet(State);
-            if ((a & 1) == 0 && AtomicCas(&State, a + 2, a)) {
+            std::atomic_signed_lock_free::value_type a = State.load(std::memory_order_acquire);
+            if ((a & 1) == 0 && State.compare_exchange_strong(a, a + 2, std::memory_order_acquire)) {
                 break;
             }
             SpinLockPause();
@@ -44,25 +44,29 @@ struct TRWSpinLock {
     }
 
     void ReleaseRead() noexcept {
-        AtomicAdd(State, -2);
+        State.fetch_add(-2, std::memory_order_release);
     }
 
     void AcquireWrite() noexcept {
         while (true) {
-            TAtomic a = AtomicGet(State);
-            if ((a & 1) == 0 && AtomicCas(&State, a + 1, a)) {
+            std::atomic_signed_lock_free::value_type a = State.load(std::memory_order_acquire);
+            if ((a & 1) == 0 && State.compare_exchange_strong(a, a + 1, std::memory_order_acquire)) {
                 break;
             }
             SpinLockPause();
         }
 
-        while (!AtomicCas(&State, TAtomicBase(-1), 1)) {
+        while (true) {
+            std::atomic_signed_lock_free::value_type a = 1;
+            if (State.compare_exchange_strong(a, -1, std::memory_order_acquire)) {
+                break;
+            }
             SpinLockPause();
         }
     }
 
     void ReleaseWrite() noexcept {
-        AtomicSet(State, 0);
+        State.store(0, std::memory_order_release);
     }
 };