BlueStore: add fast check against empty list

Signed-off-by: xie xingguo <xie.xingguo@zte.com.cn>

diff --git a/src/os/bluestore/BlueStore.cc b/src/os/bluestore/BlueStore.cc
index 3a02b17ffb84523df6cd53712bbc57f347e23243..f2e422e19ccd779f8e464520cd4eb267a74994ee 100644 (file)
--- a/src/os/bluestore/BlueStore.cc
+++ b/src/os/bluestore/BlueStore.cc
@@ -596,6 +596,9 @@ int BlueStore::OnodeHashLRU::trim(int max)
           << " size " << onode_map.size() << dendl;
   int trimmed = 0;
   int num = onode_map.size() - max;
+  if (onode_map.size() == 0 || num <= 0)
+    return 0; // don't even try
+  
   lru_list_t::iterator p = lru.end();
   if (num)
     --p;