diff --git a/services/bufferhub/BufferNode.cpp b/services/bufferhub/BufferNode.cpp
index 4bad829..cc87e15 100644
--- a/services/bufferhub/BufferNode.cpp
+++ b/services/bufferhub/BufferNode.cpp
@@ -14,10 +14,10 @@
     // Using placement new here to reuse shared memory instead of new allocation
     // Initialize the atomic variables to zero.
     BufferHubDefs::MetadataHeader* metadata_header = metadata_.metadata_header();
-    buffer_state_ = new (&metadata_header->buffer_state) std::atomic<uint64_t>(0);
-    fence_state_ = new (&metadata_header->fence_state) std::atomic<uint64_t>(0);
+    buffer_state_ = new (&metadata_header->buffer_state) std::atomic<uint32_t>(0);
+    fence_state_ = new (&metadata_header->fence_state) std::atomic<uint32_t>(0);
     active_clients_bit_mask_ =
-            new (&metadata_header->active_clients_bit_mask) std::atomic<uint64_t>(0);
+            new (&metadata_header->active_clients_bit_mask) std::atomic<uint32_t>(0);
 }
 
 // Allocates a new BufferNode.
@@ -74,22 +74,22 @@
     }
 }
 
-uint64_t BufferNode::GetActiveClientsBitMask() const {
+uint32_t BufferNode::GetActiveClientsBitMask() const {
     return active_clients_bit_mask_->load(std::memory_order_acquire);
 }
 
-uint64_t BufferNode::AddNewActiveClientsBitToMask() {
-    uint64_t current_active_clients_bit_mask = GetActiveClientsBitMask();
-    uint64_t client_state_mask = 0ULL;
-    uint64_t updated_active_clients_bit_mask = 0ULL;
+uint32_t BufferNode::AddNewActiveClientsBitToMask() {
+    uint32_t current_active_clients_bit_mask = GetActiveClientsBitMask();
+    uint32_t client_state_mask = 0U;
+    uint32_t updated_active_clients_bit_mask = 0U;
     do {
         client_state_mask =
                 BufferHubDefs::FindNextAvailableClientStateMask(current_active_clients_bit_mask);
-        if (client_state_mask == 0ULL) {
+        if (client_state_mask == 0U) {
             ALOGE("%s: reached the maximum number of channels per buffer node: %d.", __FUNCTION__,
                   BufferHubDefs::kMaxNumberOfClients);
             errno = E2BIG;
-            return 0ULL;
+            return 0U;
         }
         updated_active_clients_bit_mask = current_active_clients_bit_mask | client_state_mask;
     } while (!(active_clients_bit_mask_->compare_exchange_weak(current_active_clients_bit_mask,
@@ -99,7 +99,7 @@
     return client_state_mask;
 }
 
-void BufferNode::RemoveClientsBitFromMask(const uint64_t& value) {
+void BufferNode::RemoveClientsBitFromMask(const uint32_t& value) {
     active_clients_bit_mask_->fetch_and(~value);
 }
 
diff --git a/services/bufferhub/include/bufferhub/BufferHubIdGenerator.h b/services/bufferhub/include/bufferhub/BufferHubIdGenerator.h
index c5b2cde..b51fcda 100644
--- a/services/bufferhub/include/bufferhub/BufferHubIdGenerator.h
+++ b/services/bufferhub/include/bufferhub/BufferHubIdGenerator.h
@@ -32,7 +32,7 @@
 class BufferHubIdGenerator {
 public:
     // 0 is considered invalid
-    static constexpr uint32_t kInvalidId = 0UL;
+    static constexpr uint32_t kInvalidId = 0U;
 
     // Get the singleton instance of this class
     static BufferHubIdGenerator& getInstance();
diff --git a/services/bufferhub/include/bufferhub/BufferNode.h b/services/bufferhub/include/bufferhub/BufferNode.h
index 02bb5af..cf56c33 100644
--- a/services/bufferhub/include/bufferhub/BufferNode.h
+++ b/services/bufferhub/include/bufferhub/BufferNode.h
@@ -38,19 +38,19 @@
     // Gets the current value of active_clients_bit_mask in metadata_ with
     // std::memory_order_acquire, so that all previous releases of
     // active_clients_bit_mask from all threads will be returned here.
-    uint64_t GetActiveClientsBitMask() const;
+    uint32_t GetActiveClientsBitMask() const;
 
     // Find and add a new client_state_mask to active_clients_bit_mask in
     // metadata_.
     // Return the new client_state_mask that is added to active_clients_bit_mask.
-    // Return 0ULL if there are already 32 bp clients of the buffer.
-    uint64_t AddNewActiveClientsBitToMask();
+    // Return 0U if there are already 16 clients of the buffer.
+    uint32_t AddNewActiveClientsBitToMask();
 
     // Removes the value from active_clients_bit_mask in metadata_ with
     // std::memory_order_release, so that the change will be visible to any
     // acquire of active_clients_bit_mask_ in any threads after the succeed of
     // this operation.
-    void RemoveClientsBitFromMask(const uint64_t& value);
+    void RemoveClientsBitFromMask(const uint32_t& value);
 
 private:
     // Helper method for constructors to initialize atomic metadata header
@@ -75,14 +75,14 @@
 
     // buffer_state_ tracks the state of the buffer. Buffer can be in one of these
     // four states: gained, posted, acquired, released.
-    std::atomic<uint64_t>* buffer_state_ = nullptr;
+    std::atomic<uint32_t>* buffer_state_ = nullptr;
 
     // TODO(b/112012161): add comments to fence_state_.
-    std::atomic<uint64_t>* fence_state_ = nullptr;
+    std::atomic<uint32_t>* fence_state_ = nullptr;
 
     // active_clients_bit_mask_ tracks all the bp clients of the buffer. It is the
     // union of all client_state_mask of all bp clients.
-    std::atomic<uint64_t>* active_clients_bit_mask_ = nullptr;
+    std::atomic<uint32_t>* active_clients_bit_mask_ = nullptr;
 };
 
 } // namespace implementation
diff --git a/services/bufferhub/tests/BufferNode_test.cpp b/services/bufferhub/tests/BufferNode_test.cpp
index 8555eb7..dbf10e8 100644
--- a/services/bufferhub/tests/BufferNode_test.cpp
+++ b/services/bufferhub/tests/BufferNode_test.cpp
@@ -56,21 +56,21 @@
 }
 
 TEST_F(BufferNodeTest, TestAddNewActiveClientsBitToMask_twoNewClients) {
-    uint64_t new_client_state_mask_1 = buffer_node->AddNewActiveClientsBitToMask();
+    uint32_t new_client_state_mask_1 = buffer_node->AddNewActiveClientsBitToMask();
     EXPECT_EQ(buffer_node->GetActiveClientsBitMask(), new_client_state_mask_1);
 
     // Request and add a new client_state_mask again.
     // Active clients bit mask should be the union of the two new
     // client_state_masks.
-    uint64_t new_client_state_mask_2 = buffer_node->AddNewActiveClientsBitToMask();
+    uint32_t new_client_state_mask_2 = buffer_node->AddNewActiveClientsBitToMask();
     EXPECT_EQ(buffer_node->GetActiveClientsBitMask(),
               new_client_state_mask_1 | new_client_state_mask_2);
 }
 
 TEST_F(BufferNodeTest, TestAddNewActiveClientsBitToMask_32NewClients) {
-    uint64_t new_client_state_mask = 0ULL;
-    uint64_t current_mask = 0ULL;
-    uint64_t expected_mask = 0ULL;
+    uint32_t new_client_state_mask = 0U;
+    uint32_t current_mask = 0U;
+    uint32_t expected_mask = 0U;
 
     for (int i = 0; i < BufferHubDefs::kMaxNumberOfClients; ++i) {
         new_client_state_mask = buffer_node->AddNewActiveClientsBitToMask();
@@ -83,14 +83,14 @@
 
     // Method should fail upon requesting for more than maximum allowable clients.
     new_client_state_mask = buffer_node->AddNewActiveClientsBitToMask();
-    EXPECT_EQ(new_client_state_mask, 0ULL);
+    EXPECT_EQ(new_client_state_mask, 0U);
     EXPECT_EQ(errno, E2BIG);
 }
 
 TEST_F(BufferNodeTest, TestRemoveActiveClientsBitFromMask) {
     buffer_node->AddNewActiveClientsBitToMask();
-    uint64_t current_mask = buffer_node->GetActiveClientsBitMask();
-    uint64_t new_client_state_mask = buffer_node->AddNewActiveClientsBitToMask();
+    uint32_t current_mask = buffer_node->GetActiveClientsBitMask();
+    uint32_t new_client_state_mask = buffer_node->AddNewActiveClientsBitToMask();
     EXPECT_NE(buffer_node->GetActiveClientsBitMask(), current_mask);
 
     buffer_node->RemoveClientsBitFromMask(new_client_state_mask);