ESubtreeMap類分析

ESubtreeMap類說明:
 class ESubtreeMap: public LogEvent {
  EMetaBlob metablob;
  map<dirfrag_t, vector<dirfrag_t>> subtrees;
  set<dirfrag_t> ambiguous_subtrees;
  uint64_t expire_pos;
  uint64_t event_seq;
 }:
 
ESubtreeMap類方法：
ESubtreeMap::replay(mds)
|__若expire_pos有效且大於當前MDLog中journaler的expire pos 
  |__設置MDLog的journaler expire pos值，即：mds->mdlog->journaler->set_expire_pos(expire_pos)
|__若MDCache是subtrees
  |__遍歷subtrees
    |__從MDCache中獲得subtree_root對應的CDir
    |__檢查subtree root對應的CDir是不是subtree
    |__遍歷subtree_root下面的全部dirfrags
      |__在MDCache中執行get_force_dirfrag操做，即：mds->mdcache->get_force_dirfrag()
    |__在MDCache中獲得subtree_root的subtree bound，即：mds->mdcache->get_subtree_bound()
    |__遍歷subtree_root下面的全部dirfrags
      |__從subtree bound數組中刪除dirfrags
    |__若ambiguous_subtrees數組中包含subtree_root
      |__檢查MDCache中是否在ambiguous中包含subtree_root，即：mds->mdcache->have_ambiguous_import()
    |__若ambiguous_subtrees數組中不包含subtree_root
      |__檢查MDCache中是否在ambiguous中包含subtree_root，即：mds->mdcache->have_ambiguous_import()
  |__從MDCache中獲得subtrees，即：mds->mdcache->list_subtrees()
  |__遍歷MDCache中的subtrees
    |__檢查MDCache着那個的subtrees是否在ESubtreeMap類的subtrees集合中
|__執行EMetaBlob::replay操做
|__遍歷subtrees數組
  |__從MDCache中獲得subtree_root對應的CDir
  |__檢查subtree_root是否在ambiguous_subtrees數組中
    |__在MDCache中添加ambiguous信息，即：mds->mdcache->add_ambiguous_import()
    |__在MDCache中調整subtree auth，即：mds->mdcache->adjust_bounded_subtree_auth()
  |__subtree_root再也不ambiguous_subtrees數組中
    |__在MDCache中調整subtree auth，即：mds->mdcache->adjust_bounded_subtree_auth()
|__在MDCache中執行recalc auth bits，即：mds->mdcache->recalc_auth_bits()