diff --git a/services/core/jni/com_android_server_am_CachedAppOptimizer.cpp b/services/core/jni/com_android_server_am_CachedAppOptimizer.cpp
index cfc63f0..7b08413 100644
--- a/services/core/jni/com_android_server_am_CachedAppOptimizer.cpp
+++ b/services/core/jni/com_android_server_am_CachedAppOptimizer.cpp
@@ -54,6 +54,9 @@
 using android::meminfo::ProcMemInfo;
 using namespace android::meminfo;
 
+static const size_t kPageSize = getpagesize();
+static const size_t kPageMask = ~(kPageSize - 1);
+
 #define COMPACT_ACTION_FILE_FLAG 1
 #define COMPACT_ACTION_ANON_FLAG 2
 
@@ -64,7 +67,7 @@
 #define ASYNC_RECEIVED_WHILE_FROZEN (2)
 #define TXNS_PENDING_WHILE_FROZEN (4)
 
-#define MAX_RW_COUNT (INT_MAX & PAGE_MASK)
+#define MAX_RW_COUNT (INT_MAX & kPageMask)
 
 // Defines the maximum amount of VMAs we can send per process_madvise syscall.
 // Currently this is set to UIO_MAXIOV which is the maximum segments allowed by
@@ -233,7 +236,6 @@
 // process_madvise on failure
 int madviseVmasFromBatch(unique_fd& pidfd, VmaBatch& batch, int madviseType,
                          uint64_t* outBytesProcessed) {
-    static const size_t kPageSize = getpagesize();
     if (batch.totalVmas == 0 || batch.totalBytes == 0) {
         // No VMAs in Batch, skip.
         *outBytesProcessed = 0;