8361948: Shenandoah: region free capacity unit mismatch

Backport-of: 46988e1073e9a2b47491c90143b1f261fe56da56

Author: Xiaolong Peng

src/hotspot/share/gc/shenandoah/shenandoahFreeSet.cpp

@@ -880,7 +880,7 @@ HeapWord* ShenandoahFreeSet::allocate_from_regions(Iter& iterator, ShenandoahAll
   for (idx_t idx = iterator.current(); iterator.has_next(); idx = iterator.next()) {
     ShenandoahHeapRegion* r = _heap->get_region(idx);
     size_t min_size = (req.type() == ShenandoahAllocRequest::_alloc_tlab) ? req.min_size() : req.size();
-    if (alloc_capacity(r) >= min_size) {
+    if (alloc_capacity(r) >= min_size * HeapWordSize) {
       HeapWord* result = try_allocate_in(r, req, in_new_region);
       if (result != nullptr) {
         return result;