8286496: Improve Thread labels

Reviewed-by: andrew
Backport-of: e733e55de88e63e129f15edefc602c050339b38a

Author: martinuy

hotspot/src/share/vm/jfr/recorder/checkpoint/jfrCheckpointManager.cpp

@@ -156,7 +156,9 @@ bool JfrCheckpointManager::is_locked() const {
 }
 
 static void assert_free_lease(const BufferPtr buffer) {
-  assert(buffer != NULL, "invariant");
+  if (buffer == NULL) {
+    return;
+  }
   assert(buffer->acquired_by_self(), "invariant");
   assert(buffer->lease(), "invariant");
 }

hotspot/src/share/vm/jfr/recorder/storage/jfrBuffer.cpp

@@ -38,11 +38,13 @@ JfrBuffer::JfrBuffer() : _next(NULL),
                          _top(NULL),
                          _flags(0),
                          _header_size(0),
-                         _size(0) {}
+                         _size(0)
+                         LP64_ONLY(COMMA _pad(0)) {}
 
 bool JfrBuffer::initialize(size_t header_size, size_t size, const void* id /* NULL */) {
-  _header_size = (u2)header_size;
-  _size = (u4)(size / BytesPerWord);
+  assert(header_size <= max_jushort, "invariant");
+  _header_size = static_cast<u2>(header_size);
+  _size = size;
   assert(_identity == NULL, "invariant");
   _identity = id;
   set_pos(start());

hotspot/src/share/vm/jfr/recorder/storage/jfrBuffer.hpp

@@ -52,9 +52,10 @@ class JfrBuffer {
   const void* volatile _identity;
   u1* _pos;
   mutable const u1* volatile _top;
-  u2 _flags;
+  size_t _size;
   u2 _header_size;
-  u4 _size;
+  u2 _flags;
+  LP64_ONLY(const u4 _pad;)
 
   const u1* stable_top() const;
 
@@ -124,7 +125,7 @@ class JfrBuffer {
   }
 
   size_t size() const {
-    return _size * BytesPerWord;
+    return _size;
   }
 
   size_t total_size() const {

hotspot/src/share/vm/jfr/recorder/storage/jfrMemorySpace.hpp

@@ -108,19 +108,27 @@ class JfrMemorySpace : public JfrCHeapObj {
 };
 
 // allocations are even multiples of the mspace min size
-inline u8 align_allocation_size(u8 requested_size, size_t min_elem_size) {
+inline size_t align_allocation_size(size_t requested_size, size_t min_elem_size) {
   assert((int)min_elem_size % os::vm_page_size() == 0, "invariant");
+  if (requested_size > static_cast<size_t>(min_intx)) {
+    assert(false, err_msg("requested size: " SIZE_FORMAT " is too large", requested_size));
+    return 0;
+  }
   u8 alloc_size_bytes = min_elem_size;
   while (requested_size > alloc_size_bytes) {
     alloc_size_bytes <<= 1;
   }
   assert((int)alloc_size_bytes % os::vm_page_size() == 0, "invariant");
-  return alloc_size_bytes;
+  assert(alloc_size_bytes <= static_cast<size_t>(min_intx), "invariant");
+  return static_cast<size_t>(alloc_size_bytes);
 }
 
 template <typename T, template <typename> class RetrievalType, typename Callback>
 T* JfrMemorySpace<T, RetrievalType, Callback>::allocate(size_t size) {
-  const u8 aligned_size_bytes = align_allocation_size(size, _min_elem_size);
+  const size_t aligned_size_bytes = align_allocation_size(size, _min_elem_size);
+  if (size != 0 && aligned_size_bytes == 0) {
+    return NULL;
+  }
   void* const allocation = JfrCHeapObj::new_array<u1>(aligned_size_bytes + sizeof(T));
   if (allocation == NULL) {
     return NULL;

hotspot/src/share/vm/jfr/writers/jfrWriterHost.inline.hpp

@@ -70,6 +70,7 @@ template <typename T>
 inline void WriterHost<BE, IE, WriterPolicyImpl>::write(const T* value, size_t len) {
   assert(value != NULL, "invariant");
   assert(len > 0, "invariant");
+  assert(len <= max_jint, "invariant");
   // Might need T + 1 size
   u1* const pos = ensure_size(sizeof(T) * len + len);
   if (pos) {
@@ -125,8 +126,9 @@ template <typename T>
 inline void WriterHost<BE, IE, WriterPolicyImpl>::be_write(const T* value, size_t len) {
   assert(value != NULL, "invariant");
   assert(len > 0, "invariant");
-  // Might need T + 1 size
-  u1* const pos = ensure_size(sizeof(T) * len + len);
+  assert(len <= max_jint, "invariant");
+  // Big endian writes map one-to-one for length, so no extra space is needed.
+  u1* const pos = ensure_size(sizeof(T) * len);
   if (pos) {
     this->set_current_pos(BE::be_write(value, len, pos));
   }

hotspot/src/share/vm/prims/jni.cpp

@@ -191,8 +191,6 @@ static jint CurrentVersion = JNI_VERSION_1_8;
 #define FP_SELECT(TypeName, intcode, fpcode) \
   FP_SELECT_##TypeName(intcode, fpcode)
 
-#define COMMA ,
-
 // Choose DT_RETURN_MARK macros  based on the type: float/double -> void
 // (dtrace doesn't do FP yet)
 #ifndef USDT2

hotspot/src/share/vm/utilities/macros.hpp

@@ -34,6 +34,9 @@
 // Makes a string of the macro expansion of a
 #define XSTR(a) STR(a)
 
+// Allow commas in macro arguments.
+#define COMMA ,
+
 // -DINCLUDE_<something>=0 | 1 can be specified on the command line to include
 // or exclude functionality.