diff --git a/crypto/threads_pthread.c b/crypto/threads_pthread.c
index 28bd38c57c..e1c7f3c979 100644
--- a/crypto/threads_pthread.c
+++ b/crypto/threads_pthread.c
@@ -106,6 +106,7 @@ static inline void *apple_atomic_load_n_pvoid(void **p,
 #  define ATOMIC_STORE_N(t, p, v, o) __atomic_store_n(p, v, o)
 #  define ATOMIC_STORE(t, p, v, o) __atomic_store(p, v, o)
 #  define ATOMIC_EXCHANGE_N(t, p, v, o) __atomic_exchange_n(p, v, o)
+#  define ATOMIC_COMPARE_EXCHANGE_N(t, p, e, d, s, f) __atomic_compare_exchange_n(p, e, d, 0, s, f)
 #  define ATOMIC_ADD_FETCH(p, v, o) __atomic_add_fetch(p, v, o)
 #  define ATOMIC_FETCH_ADD(p, v, o) __atomic_fetch_add(p, v, o)
 #  define ATOMIC_SUB_FETCH(p, v, o) __atomic_sub_fetch(p, v, o)
@@ -172,6 +173,23 @@ IMPL_fallback_atomic_exchange_n(prcu_cb_item)
 
 #  define ATOMIC_EXCHANGE_N(t, p, v, o) fallback_atomic_exchange_n_##t(p, v)
 
+#  define IMPL_fallback_atomic_compare_exchange_n(t)                                  \
+    static ossl_inline int fallback_atomic_compare_exchange_n_##t(t *p, t *e, t d, s, f) \
+    {                                                                                 \
+        int ret = 1;                                                                 \
+        pthread_mutex_lock(&atomic_sim_lock);                                         \
+        if (*p == *e)                                                                 \
+            *p = d;                                                                    \
+        else                                                                          \
+            ret = 0;                                                                   \
+        pthread_mutex_unlock(&atomic_sim_lock);                                       \
+        return ret;                                                                   \
+    }
+
+IMPL_fallback_atomic_exchange_n(uint64_t)
+
+#  define ATOMIC_COMPARE_EXCHANGE_N(t, p, e, d, s, f) fallback_atomic_compare_exchange_n_##t(p, e, d, s, f)
+
 /*
  * The fallbacks that follow don't need any per type implementation, as
  * they are designed for uint64_t only.  If there comes a time when multiple
@@ -477,6 +495,8 @@ void ossl_rcu_read_unlock(CRYPTO_RCU_LOCK *lock)
 static struct rcu_qp *update_qp(CRYPTO_RCU_LOCK *lock)
 {
     uint64_t new_id;
+    uint64_t update;
+    uint64_t ret;
     uint64_t current_idx;
 
     pthread_mutex_lock(&lock->alloc_lock);
@@ -510,10 +530,13 @@ static struct rcu_qp *update_qp(CRYPTO_RCU_LOCK *lock)
      * of this update are published to the read side prior to updating the
      * reader idx below
      */
-    ATOMIC_AND_FETCH(&lock->qp_group[current_idx].users, ID_MASK,
-                     __ATOMIC_RELEASE);
-    ATOMIC_OR_FETCH(&lock->qp_group[current_idx].users, new_id,
-                    __ATOMIC_RELEASE);
+try_again:
+    ret = ATOMIC_LOAD_N(uint64_t, &lock->qp_group[current_idx].users, __ATOMIC_ACQUIRE);
+    update = ret & ID_MASK;
+    update |= new_id;
+    if (!ATOMIC_COMPARE_EXCHANGE_N(uint64_t, &lock->qp_group[current_idx].users, &ret, update,
+                                   __ATOMIC_ACQ_REL, __ATOMIC_RELAXED))
+        goto try_again;
 
     /*
      * Update the reader index to be the prior qp.