From: Yan, Zheng <zheng.z.yan@intel.com>
Date: Thu, 14 Mar 2013 04:27:51 +0000 (+0800)
Subject: mds: don't send resolve message between active MDS
X-Git-Tag: v0.62~120^2~28
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=ed85dd61a5a663ee79fd9468e37d734f77b1a63f;p=ceph.git

mds: don't send resolve message between active MDS

When MDS cluster is resolving, current behavior is sending subtree resolve
message to all other MDS and waiting for all other MDS' resolve message.
The problem is that active MDS can have diffent subtree map due to rename.
Besides gathering active MDS's resolve messages are also racy. The only
function for these messages is disambiguate other MDS' import. We can
replace it by import finish notification.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
---

diff --git a/src/mds/MDCache.cc b/src/mds/MDCache.cc
index d3a15981a12..e360465c2cb 100644
--- a/src/mds/MDCache.cc
+++ b/src/mds/MDCache.cc
@@ -2521,7 +2521,8 @@ void MDCache::send_subtree_resolves()
        ++p) {
     if (*p == mds->whoami)
       continue;
-    resolves[*p] = new MMDSResolve;
+    if (mds->is_resolve() || mds->mdsmap->is_resolve(*p))
+      resolves[*p] = new MMDSResolve;
   }
 
   // known
@@ -2841,7 +2842,7 @@ void MDCache::handle_resolve(MMDSResolve *m)
 	  migrator->import_reverse(dir);
 	} else {
 	  dout(7) << "ambiguous import succeeded on " << *dir << dendl;
-	  migrator->import_finish(dir);
+	  migrator->import_finish(dir, true);
 	}
 	my_ambiguous_imports.erase(p);  // no longer ambiguous.
       }
@@ -3436,7 +3437,12 @@ void MDCache::rejoin_send_rejoins()
        ++p) {
     CDir *dir = p->first;
     assert(dir->is_subtree_root());
-    assert(!dir->is_ambiguous_dir_auth());
+    if (dir->is_ambiguous_dir_auth()) {
+      // exporter is recovering, importer is survivor.
+      assert(rejoins.count(dir->authority().first));
+      assert(!rejoins.count(dir->authority().second));
+      continue;
+    }
 
     // my subtree?
     if (dir->is_auth())
diff --git a/src/mds/Migrator.cc b/src/mds/Migrator.cc
index b485ab11a9d..604a78c908d 100644
--- a/src/mds/Migrator.cc
+++ b/src/mds/Migrator.cc
@@ -2088,6 +2088,23 @@ void Migrator::import_reverse(CDir *dir)
   }
 }
 
+void Migrator::import_notify_finish(CDir *dir, set<CDir*>& bounds)
+{
+  dout(7) << "import_notify_finish " << *dir << dendl;
+
+  for (set<int>::iterator p = import_bystanders[dir].begin();
+       p != import_bystanders[dir].end();
+       ++p) {
+    MExportDirNotify *notify =
+      new MExportDirNotify(dir->dirfrag(), false,
+			   pair<int,int>(import_peer[dir->dirfrag()], mds->get_nodeid()),
+			   pair<int,int>(mds->get_nodeid(), CDIR_AUTH_UNKNOWN));
+    for (set<CDir*>::iterator i = bounds.begin(); i != bounds.end(); i++)
+      notify->get_bounds().push_back((*i)->dirfrag());
+    mds->send_message_mds(notify, *p);
+  }
+}
+
 void Migrator::import_notify_abort(CDir *dir, set<CDir*>& bounds)
 {
   dout(7) << "import_notify_abort " << *dir << dendl;
@@ -2183,11 +2200,11 @@ void Migrator::handle_export_finish(MExportDirFinish *m)
   CDir *dir = cache->get_dirfrag(m->get_dirfrag());
   assert(dir);
   dout(7) << "handle_export_finish on " << *dir << dendl;
-  import_finish(dir);
+  import_finish(dir, false);
   m->put();
 }
 
-void Migrator::import_finish(CDir *dir) 
+void Migrator::import_finish(CDir *dir, bool notify)
 {
   dout(7) << "import_finish on " << *dir << dendl;
 
@@ -2205,6 +2222,10 @@ void Migrator::import_finish(CDir *dir)
   // remove pins
   set<CDir*> bounds;
   cache->get_subtree_bounds(dir, bounds);
+
+  if (notify)
+    import_notify_finish(dir, bounds);
+
   import_remove_pins(dir, bounds);
 
   map<CInode*, map<client_t,Capability::Export> > cap_imports;
diff --git a/src/mds/Migrator.h b/src/mds/Migrator.h
index 7988f325ff1..2889a74f491 100644
--- a/src/mds/Migrator.h
+++ b/src/mds/Migrator.h
@@ -273,12 +273,13 @@ protected:
   void import_reverse_unfreeze(CDir *dir);
   void import_reverse_final(CDir *dir);
   void import_notify_abort(CDir *dir, set<CDir*>& bounds);
+  void import_notify_finish(CDir *dir, set<CDir*>& bounds);
   void import_logged_start(dirfrag_t df, CDir *dir, int from,
 			   map<client_t,entity_inst_t> &imported_client_map,
 			   map<client_t,uint64_t>& sseqmap);
   void handle_export_finish(MExportDirFinish *m);
 public:
-  void import_finish(CDir *dir);
+  void import_finish(CDir *dir, bool notify);
 protected:
 
   void handle_export_caps(MExportCaps *m);