mds: redo choose_loner/drop_loner

Still need a simple_excl() with a try_choose_loner() check, and something
in simple_eval.

src/mds/CInode.h

@@ -479,8 +479,9 @@ public:
   // client caps
   int loner_cap;
 
-  bool choose_loner() {
-    assert(loner_cap < 0);
+  bool try_choose_loner() {
+    if (loner_cap >= 0)
+      return true;
 
     if (!mds_caps_wanted.empty())
       return false;
@@ -503,6 +504,21 @@ public:
     }
     return false;
   }
+  
+  bool try_drop_loner() {
+    if (loner_cap < 0)
+      return true;
+
+    int other_allowed = get_caps_allowed(false);
+    Capability *cap = get_client_cap(loner_cap);
+    if (!cap ||
+	(cap->issued() & ~other_allowed) == 0) {
+      loner_cap = -1;
+      return true;
+    }
+    return false;
+  }
+
 
   int count_nonstale_caps() {
     int n = 0;
@@ -560,6 +576,9 @@ public:
     cap->rdcaps_item.remove_myself();
     containing_realm->remove_cap(client, cap);
 
+    if (client == loner_cap)
+      loner_cap = -1;
+
     delete cap;
     client_caps.erase(client);
     if (client_caps.empty()) {

src/mds/Locker.cc

@@ -464,9 +464,6 @@ void Locker::eval_gather(SimpleLock *lock)
 	return;
       }
       
-      if (in && lock->get_state() != LOCK_EXCL)
-	in->loner_cap = -1;
-
       switch (lock->get_state()) {
 	// to mixed
       case LOCK_TSYN_MIX:
@@ -492,6 +489,9 @@ void Locker::eval_gather(SimpleLock *lock)
       lock->get_parent()->auth_unpin(lock);
     }
 
+    if (in)
+      in->try_drop_loner();
+
     lock->set_state(next);
     lock->finish_waiters(SimpleLock::WAIT_STABLE|SimpleLock::WAIT_WR|SimpleLock::WAIT_RD|SimpleLock::WAIT_XLOCK);
     
@@ -531,7 +531,6 @@ void Locker::eval(SimpleLock *lock)
 }
 
 
-
 // ------------------
 // rdlock
 
@@ -2158,7 +2157,8 @@ bool Locker::simple_sync(SimpleLock *lock)
     lock->encode_locked_state(data);
     send_lock_message(lock, LOCK_AC_SYNC, data);
   }
-
+  if (in)
+    in->try_drop_loner();
   lock->set_state(LOCK_SYNC);
   lock->finish_waiters(SimpleLock::WAIT_RD|SimpleLock::WAIT_STABLE);
   return true;
@@ -2224,8 +2224,9 @@ void Locker::simple_lock(SimpleLock *lock)
   if (gather) {
     lock->get_parent()->auth_pin(lock);
   } else {
+    if (in)
+      in->try_drop_loner();
     lock->set_state(LOCK_LOCK);
-    in->loner_cap = -1;
     lock->finish_waiters(FileLock::WAIT_XLOCK|FileLock::WAIT_WR|FileLock::WAIT_STABLE);
   }
 }
@@ -2591,6 +2592,9 @@ bool Locker::scatter_scatter_fastpath(ScatterLock *lock)
       lock->encode_locked_state(data);
       send_lock_message(lock, LOCK_AC_SCATTER, data);
     } 
+    
+    ((CInode *)lock->get_parent())->try_drop_loner();
+
     lock->set_state(LOCK_MIX);
     lock->finish_waiters(ScatterLock::WAIT_WR|ScatterLock::WAIT_STABLE);
     return true;
@@ -2671,6 +2675,8 @@ void Locker::scatter_tempsync(ScatterLock *lock)
   }
   
   // do tempsync
+  ((CInode *)lock->get_parent())->try_drop_loner();
+
   lock->set_state(LOCK_TSYN);
   lock->finish_waiters(ScatterLock::WAIT_RD|ScatterLock::WAIT_STABLE);
 }
@@ -2984,10 +2990,10 @@ void Locker::file_eval(FileLock *lock)
 	   !lock->is_rdlocked() &&
 	   !lock->is_waiter_for(SimpleLock::WAIT_WR) &&
 	   ((wanted & (CEPH_CAP_GWR|CEPH_CAP_GWRBUFFER)) || in->inode.is_dir()) &&
-	   in->choose_loner()) {
+	   in->try_choose_loner()) {
     dout(7) << "file_eval stable, bump to loner " << *lock
 	    << " on " << *lock->get_parent() << dendl;
-    file_loner(lock);
+    file_excl(lock);
   }
 
   // * -> mixed?
@@ -3080,15 +3086,15 @@ void Locker::file_mixed(FileLock *lock)
     if (gather)
       lock->get_parent()->auth_pin(lock);
     else {
+      in->try_drop_loner();
       lock->set_state(LOCK_MIX);
-      in->loner_cap = -1;
       issue_caps(in);
     }
   }
 }
 
 
-void Locker::file_loner(FileLock *lock)
+void Locker::file_excl(FileLock *lock)
 {
   CInode *in = (CInode*)lock->get_parent();
   dout(7) << "file_loner " << *lock << " on " << *lock->get_parent() << dendl;  

src/mds/Locker.h

@@ -102,21 +102,14 @@ public:
   // simple
 public:
   void try_simple_eval(SimpleLock *lock);
-  void simple_eval_gather(SimpleLock *lock);
   bool simple_rdlock_try(SimpleLock *lock, Context *con);
 protected:
   void simple_eval(SimpleLock *lock);
   void handle_simple_lock(SimpleLock *lock, MLock *m);
+
   bool simple_sync(SimpleLock *lock);
   void simple_lock(SimpleLock *lock);
   void simple_xlock(SimpleLock *lock);
-  bool simple_rdlock_start(SimpleLock *lock, MDRequest *mut);
-  void simple_rdlock_finish(SimpleLock *lock, Mutation *mut);
-  bool simple_wrlock_force(SimpleLock *lock, Mutation *mut);
-  bool simple_wrlock_start(SimpleLock *lock, MDRequest *mut);
-  void simple_wrlock_finish(SimpleLock *lock, Mutation *mut);
-  bool simple_xlock_start(SimpleLock *lock, MDRequest *mut);
-  void simple_xlock_finish(SimpleLock *lock, Mutation *mut);
 
 public:
   bool dentry_can_rdlock_trace(vector<CDentry*>& trace);
@@ -127,32 +120,16 @@ public:
 public:
   void try_scatter_eval(ScatterLock *lock);
   void scatter_eval(ScatterLock *lock);        // public for MDCache::adjust_subtree_auth()
-  void scatter_eval_gather(ScatterLock *lock);
 
   void scatter_tick();
   void scatter_nudge(ScatterLock *lock, Context *c);
 
 protected:
-  bool scatter_lock_fastpath(ScatterLock *lock);  // called by LogSegment::try_to_expire
-  void scatter_lock(ScatterLock *lock, bool nowait=false);  // called by LogSegment::try_to_expire
-
   void handle_scatter_lock(ScatterLock *lock, MLock *m);
   void _scatter_replica_lock(ScatterLock *lock, int auth);
-  void scatter_sync(ScatterLock *lock);
   bool scatter_scatter_fastpath(ScatterLock *lock);
   void scatter_scatter(ScatterLock *lock, bool nowait=false);
   void scatter_tempsync(ScatterLock *lock);
-  bool scatter_rdlock_start(ScatterLock *lock, MDRequest *mut);
-  void scatter_rdlock_finish(ScatterLock *lock, Mutation *mut);
-public:
-  bool scatter_wrlock_try(ScatterLock *lock, Mutation *mut, bool initiate);
-protected:
-  bool scatter_wrlock_start(ScatterLock *lock, MDRequest *mut);
-public:
-  void scatter_wrlock_finish(ScatterLock *lock, Mutation *mut);
-protected:
-  bool scatter_xlock_start(ScatterLock *lock, MDRequest *mut);
-  void scatter_xlock_finish(ScatterLock *lock, Mutation *mut);
 
   void scatter_writebehind(ScatterLock *lock);
   class C_Locker_ScatterWB : public Context {
@@ -182,23 +159,12 @@ protected:
 
   // file
 public:
-  void file_eval_gather(ScatterLock *lock);
   void try_file_eval(ScatterLock *lock);
   void file_eval(ScatterLock *lock);
 protected:
   void handle_file_lock(ScatterLock *lock, MLock *m);
-  bool file_sync(ScatterLock *lock);
-  void file_lock(ScatterLock *lock);
   void file_mixed(ScatterLock *lock);
-  void file_loner(ScatterLock *lock);
-  bool file_rdlock_try(ScatterLock *lock, Context *con);
-  bool file_rdlock_start(ScatterLock *lock, MDRequest *mut);
-  void file_rdlock_finish(ScatterLock *lock, Mutation *mut);
-  bool file_wrlock_force(ScatterLock *lock, Mutation *mut);
-  bool file_wrlock_start(ScatterLock *lock, MDRequest *mut);
-  void file_wrlock_finish(ScatterLock *lock, Mutation *mut);
-  bool file_xlock_start(ScatterLock *lock, MDRequest *mut);
-  void file_xlock_finish(ScatterLock *lock, Mutation *mut);
+  void file_excl(ScatterLock *lock);
 
   xlist<ScatterLock*> updated_filelocks;
 public:

src/mds/MDCache.cc

@@ -3500,7 +3500,7 @@ void MDCache::process_reconnected_caps()
 	in->loner_cap = -1;
 	if (issued & ((CEPH_CAP_GRDCACHE|CEPH_CAP_GWRBUFFER) << CEPH_CAP_SFILE)) {
 	  in->filelock.set_state(LOCK_EXCL);
-	  in->choose_loner();
+	  in->try_choose_loner();
 	} else {
 	  in->filelock.set_state(LOCK_MIX);
 	}