[api] Tweak SharedMemoryStatistics Api

Move the API from Isolate to V8 and add better memory fields.

Bug: v8:7464
Change-Id: Ic82c7c74ac8f20a2f2cb896dc0203fdd0b5d8d5f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1905546Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64856}

include/v8.h

@@ -7457,21 +7457,23 @@ typedef size_t (*NearHeapLimitCallback)(void* data, size_t current_heap_limit,
  * Collection of shared per-process V8 memory information.
  *
  * Instances of this class can be passed to
- * v8::Isolate::GetSharedMemoryStatistics to get shared memory statistics from
- * V8.
+ * v8::V8::GetSharedMemoryStatistics to get shared memory statistics from V8.
  */
 class V8_EXPORT SharedMemoryStatistics {
  public:
   SharedMemoryStatistics();
-  size_t total_read_only_space_size() { return total_read_only_space_size_; }
-  size_t total_size() { return total_size_; }
+  size_t read_only_space_size() { return read_only_space_size_; }
+  size_t read_only_space_used_size() { return read_only_space_used_size_; }
+  size_t read_only_space_physical_size() {
+    return read_only_space_physical_size_;
+  }
 
  private:
-  size_t total_read_only_space_size_;
-  size_t total_size_;
+  size_t read_only_space_size_;
+  size_t read_only_space_used_size_;
+  size_t read_only_space_physical_size_;
 
   friend class V8;
-  friend class Isolate;
 };
 
 /**
@@ -8441,11 +8443,6 @@ class V8_EXPORT Isolate {
   template <class T>
   V8_INLINE MaybeLocal<T> GetDataFromSnapshotOnce(size_t index);
 
-  /**
-   * Get statistics about the shared memory usage.
-   */
-  void GetSharedMemoryStatistics(SharedMemoryStatistics* statistics);
-
   /**
    * Get statistics about the heap memory usage.
    */
@@ -9470,6 +9467,11 @@ class V8_EXPORT V8 {
       UnhandledExceptionCallback unhandled_exception_callback);
 #endif
 
+  /**
+   * Get statistics about the shared memory usage.
+   */
+  static void GetSharedMemoryStatistics(SharedMemoryStatistics* statistics);
+
  private:
   V8();
 

src/api/api.cc

@@ -5709,7 +5709,9 @@ bool v8::V8::Dispose() {
 }
 
 SharedMemoryStatistics::SharedMemoryStatistics()
-    : total_read_only_space_size_(0), total_size_(0) {}
+    : read_only_space_size_(0),
+      read_only_space_used_size_(0),
+      read_only_space_physical_size_(0) {}
 
 HeapStatistics::HeapStatistics()
     : total_heap_size_(0),
@@ -5763,6 +5765,12 @@ void v8::V8::InitializeExternalStartupDataFromFile(const char* snapshot_blob) {
 
 const char* v8::V8::GetVersion() { return i::Version::GetVersion(); }
 
+void V8::GetSharedMemoryStatistics(SharedMemoryStatistics* statistics) {
+  statistics->read_only_space_size_ = 0;
+  statistics->read_only_space_used_size_ = 0;
+  statistics->read_only_space_physical_size_ = 0;
+}
+
 template <typename ObjectType>
 struct InvokeBootstrapper;
 
@@ -8475,11 +8483,6 @@ i::Address* Isolate::GetDataFromSnapshotOnce(size_t index) {
   return GetSerializedDataFromFixedArray(i_isolate, list, index);
 }
 
-void Isolate::GetSharedMemoryStatistics(SharedMemoryStatistics* statistics) {
-  statistics->total_read_only_space_size_ = 0;
-  statistics->total_size_ = 0;
-}
-
 void Isolate::GetHeapStatistics(HeapStatistics* heap_statistics) {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
   i::Heap* heap = isolate->heap();