src/java.base/share/classes/sun/nio/fs/NativeBuffers.java

rev 50306 : imported patch loom-fibers

*** 23,47 ****
   * questions.
   */
  
  package sun.nio.fs;
  
  import jdk.internal.misc.Unsafe;
  
  /**
   * Factory for native buffers.
   */
  
  class NativeBuffers {
!     private NativeBuffers() { }
  
      private static final Unsafe unsafe = Unsafe.getUnsafe();
  
      private static final int TEMP_BUF_POOL_SIZE = 3;
      private static ThreadLocal<NativeBuffer[]> threadLocal =
          new ThreadLocal<NativeBuffer[]>();
  
      /**
       * Allocates a native buffer, of at least the given size, from the heap.
       */
      static NativeBuffer allocNativeBuffer(int size) {
          // Make a new one of at least 2k
--- 23,51 ----
   * questions.
   */
  
  package sun.nio.fs;
  
+ import jdk.internal.misc.JavaLangAccess;
+ import jdk.internal.misc.SharedSecrets;
  import jdk.internal.misc.Unsafe;
  
  /**
   * Factory for native buffers.
   */
  
  class NativeBuffers {
!     private static JavaLangAccess JLA = SharedSecrets.getJavaLangAccess();
  
      private static final Unsafe unsafe = Unsafe.getUnsafe();
  
      private static final int TEMP_BUF_POOL_SIZE = 3;
      private static ThreadLocal<NativeBuffer[]> threadLocal =
          new ThreadLocal<NativeBuffer[]>();
  
+     private NativeBuffers() { }
+ 
      /**
       * Allocates a native buffer, of at least the given size, from the heap.
       */
      static NativeBuffer allocNativeBuffer(int size) {
          // Make a new one of at least 2k
*** 53,63 ****
       * Returns a native buffer, of at least the given size, from the thread
       * local cache.
       */
      static NativeBuffer getNativeBufferFromCache(int size) {
          // return from cache if possible
!         NativeBuffer[] buffers = threadLocal.get();
          if (buffers != null) {
              for (int i=0; i<TEMP_BUF_POOL_SIZE; i++) {
                  NativeBuffer buffer = buffers[i];
                  if (buffer != null && buffer.size() >= size) {
                      buffers[i] = null;
--- 57,67 ----
       * Returns a native buffer, of at least the given size, from the thread
       * local cache.
       */
      static NativeBuffer getNativeBufferFromCache(int size) {
          // return from cache if possible
!         NativeBuffer[] buffers = JLA.getKernelThreadLocal(threadLocal);
          if (buffers != null) {
              for (int i=0; i<TEMP_BUF_POOL_SIZE; i++) {
                  NativeBuffer buffer = buffers[i];
                  if (buffer != null && buffer.size() >= size) {
                      buffers[i] = null;
*** 87,97 ****
       * Releases the given buffer. If there is space in the thread local cache
       * then the buffer goes into the cache; otherwise the memory is deallocated.
       */
      static void releaseNativeBuffer(NativeBuffer buffer) {
          // create cache if it doesn't exist
!         NativeBuffer[] buffers = threadLocal.get();
          if (buffers == null) {
              buffers = new NativeBuffer[TEMP_BUF_POOL_SIZE];
              buffers[0] = buffer;
              threadLocal.set(buffers);
              return;
--- 91,101 ----
       * Releases the given buffer. If there is space in the thread local cache
       * then the buffer goes into the cache; otherwise the memory is deallocated.
       */
      static void releaseNativeBuffer(NativeBuffer buffer) {
          // create cache if it doesn't exist
!         NativeBuffer[] buffers = JLA.getKernelThreadLocal(threadLocal);
          if (buffers == null) {
              buffers = new NativeBuffer[TEMP_BUF_POOL_SIZE];
              buffers[0] = buffer;
              threadLocal.set(buffers);
              return;