mds: skip inode that is being puring when opening snap past parent

we can not increase reference count of purging inodes. purging
inodes have no snapshots, so it's OK to skip them.

Signed-off-by: Yan, Zheng <zyan@redhat.com>

diff --git a/src/mds/SnapRealm.cc b/src/mds/SnapRealm.cc
index 080d44c7b5c3cc1bce80a25ff1381f1e31a032ca..14af91f8f704ea0a4d29a6f0c567ab382b72a7cd 100644 (file)
--- a/src/mds/SnapRealm.cc
+++ b/src/mds/SnapRealm.cc
@@ -115,8 +115,7 @@ bool SnapRealm::_open_parents(MDSInternalContextBase *finish, snapid_t first, sn
   assert(srnode.past_parents.size() >= open_past_parents.size());
   if (srnode.past_parents.size() > open_past_parents.size()) {
     for (map<snapid_t, snaplink_t>::iterator p = srnode.past_parents.begin();
-        p != srnode.past_parents.end();
-        ++p) {    
+        p != srnode.past_parents.end(); ) {
       dout(10) << " past_parent [" << p->second.first << "," << p->first << "] is "
               << p->second.ino << dendl;
       CInode *parent = mdcache->get_inode(p->second.ino);
@@ -126,12 +125,18 @@ bool SnapRealm::_open_parents(MDSInternalContextBase *finish, snapid_t first, sn
        mdcache->open_ino(p->second.ino, mdcache->mds->mdsmap->get_metadata_pool(), fin);
        return false;
       }
+      if (parent->state_test(CInode::STATE_PURGING)) {
+       dout(10) << " skip purging past_parent " << *parent << dendl;
+       srnode.past_parents.erase(p++);
+       continue;
+      }
       assert(parent->snaprealm);  // hmm!
       if (!parent->snaprealm->_open_parents(finish, p->second.first, p->first))
        return false;
       if (!open_past_parents.count(p->second.ino)) {
        add_open_past_parent(parent->snaprealm);
       }
+      ++p;
     }
   }