Fix #12578: Wrong error message when run out of GPU memory

paddle/fluid/memory/detail/buddy_allocator.cc

@@ -162,6 +162,8 @@ void BuddyAllocator::Free(void* p) {
 }
 
 size_t BuddyAllocator::Used() { return total_used_; }
+size_t BuddyAllocator::GetMinChunkSize() {return min_chunk_size_;};
+size_t BuddyAllocator::GetMaxChunkSize() {return max_chunk_size_;};
 
 void* BuddyAllocator::SystemAlloc(size_t size) {
   size_t index = 0;

paddle/fluid/memory/detail/buddy_allocator.h

@@ -42,6 +42,8 @@ class BuddyAllocator {
   void* Alloc(size_t unaligned_size);
   void Free(void* ptr);
   size_t Used();
+  size_t GetMinChunkSize();
+  size_t GetMaxChunkSize();
 
  public:
   // Disable copy and assignment

paddle/fluid/memory/malloc.cc

@@ -119,8 +119,8 @@ void* Alloc<platform::CUDAPlace>(platform::CUDAPlace place, size_t size) {
     LOG(WARNING) << "Cannot allocate " << size << " bytes in GPU "
                  << place.device << ", available " << avail << " bytes";
     LOG(WARNING) << "total " << total;
-    LOG(WARNING) << "GpuMinChunkSize " << platform::GpuMinChunkSize();
-    LOG(WARNING) << "GpuMaxChunkSize " << platform::GpuMaxChunkSize();
+    LOG(WARNING) << "GpuMinChunkSize " << buddy_allocator->GetMinChunkSize();
+    LOG(WARNING) << "GpuMaxChunkSize " << buddy_allocator->GetMaxChunkSize();
     LOG(WARNING) << "GPU memory used: " << Used<platform::CUDAPlace>(place);
     platform::SetDeviceId(cur_dev);
   }