From 7fc4bd19bf3d1589804b4e41dfca9692545fac99 Mon Sep 17 00:00:00 2001
From: "Yan, Zheng" <zyan@redhat.com>
Date: Tue, 7 Feb 2017 10:25:06 +0800
Subject: [PATCH] mds: disambiguate other mds' imports when cluster enters
 rejoin state

When mds cluster is in rejoin state, we know all mds have finished
their exports. All export abort notifications have been processed
by standby mds. So it's safe to disambiguate other mds' imports.

Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
---
 src/mds/MDCache.cc | 52 +++++++++++++++++++++++++++++-----------------
 src/mds/MDCache.h  |  3 ++-
 2 files changed, 35 insertions(+), 20 deletions(-)

diff --git a/src/mds/MDCache.cc b/src/mds/MDCache.cc
index c5936dd65d89..38177c602966 100644
--- a/src/mds/MDCache.cc
+++ b/src/mds/MDCache.cc
@@ -3300,7 +3300,7 @@ void MDCache::maybe_resolve_finish()
   }
 
   dout(10) << "maybe_resolve_finish got all resolves+resolve_acks, done." << dendl;
-  disambiguate_imports();
+  disambiguate_my_imports();
   finish_committed_masters();
 
   if (resolve_done) {
@@ -3488,11 +3488,11 @@ void MDCache::finish_rollback(metareqid_t reqid) {
   }
 }
 
-void MDCache::disambiguate_imports()
+void MDCache::disambiguate_other_imports()
 {
-  dout(10) << "disambiguate_imports" << dendl;
+  dout(10) << "disambiguate_other_imports" << dendl;
 
-  bool is_resolve = mds->is_resolve();
+  bool recovering = !(mds->is_clientreplay() || mds->is_active() || mds->is_stopping());
   // other nodes' ambiguous imports
   for (map<mds_rank_t, map<dirfrag_t, vector<dirfrag_t> > >::iterator p = other_ambiguous_imports.begin();
        p != other_ambiguous_imports.end();
@@ -3505,9 +3505,9 @@ void MDCache::disambiguate_imports()
 	 ++q) {
       dout(10) << " ambiguous import " << q->first << " bounds " << q->second << dendl;
       // an ambiguous import will not race with a refragmentation; it's appropriate to force here.
-      CDir *dir = get_force_dirfrag(q->first, is_resolve);
+      CDir *dir = get_force_dirfrag(q->first, recovering);
       if (!dir) continue;
-      
+
       if (dir->is_ambiguous_auth() ||	// works for me_ambig or if i am a surviving bystander
 	  dir->authority() == CDIR_AUTH_UNDEF) { // resolving
 	dout(10) << "  mds." << who << " did import " << *dir << dendl;
@@ -3519,6 +3519,18 @@ void MDCache::disambiguate_imports()
     }
   }
   other_ambiguous_imports.clear();
+}
+
+void MDCache::disambiguate_my_imports()
+{
+  dout(10) << "disambiguate_my_imports" << dendl;
+
+  if (!mds->is_resolve()) {
+    assert(my_ambiguous_imports.empty());
+    return;
+  }
+
+  disambiguate_other_imports();
 
   // my ambiguous imports
   mds_authority_t me_ambig(mds->get_nodeid(), mds->get_nodeid());
@@ -3550,18 +3562,15 @@ void MDCache::disambiguate_imports()
   assert(my_ambiguous_imports.empty());
   mds->mdlog->flush();
 
-  if (is_resolve) {
-    // verify all my subtrees are unambiguous!
-    for (map<CDir*,set<CDir*> >::iterator p = subtrees.begin();
-	 p != subtrees.end();
-	 ++p) {
-      CDir *dir = p->first;
-      if (dir->is_ambiguous_dir_auth()) {
-	dout(0) << "disambiguate_imports uh oh, dir_auth is still ambiguous for " << *dir << dendl;
-	show_subtrees();
-      }
-      assert(!dir->is_ambiguous_dir_auth());
+  // verify all my subtrees are unambiguous!
+  for (map<CDir*,set<CDir*> >::iterator p = subtrees.begin();
+       p != subtrees.end();
+       ++p) {
+    CDir *dir = p->first;
+    if (dir->is_ambiguous_dir_auth()) {
+      dout(0) << "disambiguate_imports uh oh, dir_auth is still ambiguous for " << *dir << dendl;
     }
+    assert(!dir->is_ambiguous_dir_auth());
   }
 
   show_subtrees();
@@ -3925,6 +3934,13 @@ void MDCache::rejoin_send_rejoins()
     return;
   }
 
+  assert(!migrator->is_importing());
+  assert(!migrator->is_exporting());
+
+  if (!mds->is_rejoin()) {
+    disambiguate_other_imports();
+  }
+
   map<mds_rank_t, MMDSCacheRejoin*> rejoins;
 
 
@@ -3961,8 +3977,6 @@ void MDCache::rejoin_send_rejoins()
     }
   }
   
-  assert(!migrator->is_importing());
-  assert(!migrator->is_exporting());
   
   // check all subtrees
   for (map<CDir*, set<CDir*> >::iterator p = subtrees.begin();
diff --git a/src/mds/MDCache.h b/src/mds/MDCache.h
index fc3b5fcc557b..8f0d4bb02e08 100644
--- a/src/mds/MDCache.h
+++ b/src/mds/MDCache.h
@@ -442,7 +442,8 @@ protected:
   void process_delayed_resolve();
   void discard_delayed_resolve(mds_rank_t who);
   void maybe_resolve_finish();
-  void disambiguate_imports();
+  void disambiguate_my_imports();
+  void disambiguate_other_imports();
   void trim_unlinked_inodes();
   void add_uncommitted_slave_update(metareqid_t reqid, mds_rank_t master, MDSlaveUpdate*);
   void finish_uncommitted_slave_update(metareqid_t reqid, mds_rank_t master);
-- 
2.47.3