memory: Refactor memory_region_clear_coalescing

Removing the update variable and quit earlier if the memory region has
no coalesced range.  This prepares for the next patch.

Fixes: 3ac7d43a6fbb5d4a3
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20190820141328.10009-4-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/memory.c b/memory.c
index 4aa38eb5b1a3ec89700f49656794d0cd862a32bb..9a1193a1444a12d5fa406e03c0e0a864e71c5404 100644 (file)
--- a/memory.c
+++ b/memory.c
@@ -2281,7 +2281,10 @@ void memory_region_add_coalescing(MemoryRegion *mr,
 void memory_region_clear_coalescing(MemoryRegion *mr)
 {
     CoalescedMemoryRange *cmr;
-    bool updated = false;
+
+    if (QTAILQ_EMPTY(&mr->coalesced)) {
+        return;
+    }
 
     qemu_flush_coalesced_mmio_buffer();
     mr->flush_coalesced_mmio = false;
@@ -2290,12 +2293,9 @@ void memory_region_clear_coalescing(MemoryRegion *mr)
         cmr = QTAILQ_FIRST(&mr->coalesced);
         QTAILQ_REMOVE(&mr->coalesced, cmr, link);
         g_free(cmr);
-        updated = true;
     }
 
-    if (updated) {
-        memory_region_update_coalesced_range(mr);
-    }
+    memory_region_update_coalesced_range(mr);
 }
 
 void memory_region_set_flush_coalesced(MemoryRegion *mr)