Move the master socket in the ganeti run dir

[ganeti-local] / lib / mcpu.py

diff --git a/lib/mcpu.py b/lib/mcpu.py
index 4e9659d..4bdfb46 100644 (file)
--- a/lib/mcpu.py
+++ b/lib/mcpu.py
@@ -37,6 +37,7 @@ from ganeti import cmdlib
 from ganeti import config
 from ganeti import ssconf
 from ganeti import logger
+from ganeti import locking
 
 
 class Processor(object):
@@ -98,6 +99,52 @@ class Processor(object):
     """
     self.context = context
     self._feedback_fn = feedback
+    self.exclusive_BGL = False
+
+  def _ExecLU(self, lu):
+    """Logical Unit execution sequence.
+
+    """
+    write_count = self.context.cfg.write_count
+    lu.CheckPrereq()
+    hm = HooksMaster(rpc.call_hooks_runner, self, lu)
+    h_results = hm.RunPhase(constants.HOOKS_PHASE_PRE)
+    lu.HooksCallBack(constants.HOOKS_PHASE_PRE, h_results,
+                     self._feedback_fn, None)
+    try:
+      result = lu.Exec(self._feedback_fn)
+      h_results = hm.RunPhase(constants.HOOKS_PHASE_POST)
+      result = lu.HooksCallBack(constants.HOOKS_PHASE_POST, h_results,
+                                self._feedback_fn, result)
+    finally:
+      # FIXME: This needs locks if not lu_class.REQ_BGL
+      if write_count != self.context.cfg.write_count:
+        hm.RunConfigUpdate()
+
+    return result
+
+  def _LockAndExecLU(self, lu, level):
+    """Execute a Logical Unit, with the needed locks.
+
+    This is a recursive function that starts locking the given level, and
+    proceeds up, till there are no more locks to acquire. Then it executes the
+    given LU and its opcodes.
+
+    """
+    if level in lu.needed_locks:
+      # This is always safe to do, as we can't acquire more/less locks than
+      # what was requested.
+      lu.needed_locks[level] = self.context.glm.acquire(level,
+                                                        lu.needed_locks[level])
+      try:
+        result = self._LockAndExecLU(lu, level + 1)
+      finally:
+        if lu.needed_locks[level]:
+          self.context.glm.release(level)
+    else:
+      result = self._ExecLU(lu)
+
+    return result
 
   def ExecOpCode(self, op):
     """Execute an opcode.
@@ -119,25 +166,19 @@ class Processor(object):
     else:
       sstore = ssconf.SimpleStore()
 
-    write_count = self.context.cfg.write_count
-    lu = lu_class(self, op, self.context.cfg, sstore)
-    lu.CheckPrereq()
-    hm = HooksMaster(rpc.call_hooks_runner, self, lu)
-    h_results = hm.RunPhase(constants.HOOKS_PHASE_PRE)
-    lu.HooksCallBack(constants.HOOKS_PHASE_PRE,
-                     h_results, self._feedback_fn, None)
+    # Acquire the Big Ganeti Lock exclusively if this LU requires it, and in a
+    # shared fashion otherwise (to prevent concurrent run with an exclusive LU.
+    self.context.glm.acquire(locking.LEVEL_CLUSTER, [locking.BGL],
+                             shared=not lu_class.REQ_BGL)
     try:
-      result = lu.Exec(self._feedback_fn)
-      h_results = hm.RunPhase(constants.HOOKS_PHASE_POST)
-      result = lu.HooksCallBack(constants.HOOKS_PHASE_POST,
-                       h_results, self._feedback_fn, result)
+      self.exclusive_BGL = lu_class.REQ_BGL
+      lu = lu_class(self, op, self.context, sstore)
+      lu.ExpandNames()
+      assert lu.needed_locks is not None, "needed_locks not set by LU"
+      result = self._LockAndExecLU(lu, locking.LEVEL_NODE)
     finally:
-      if lu.cfg is not None:
-        # we use lu.cfg and not self.cfg as for init cluster, self.cfg
-        # is None but lu.cfg has been recently initialized in the
-        # lu.Exec method
-        if write_count != lu.cfg.write_count:
-          hm.RunConfigUpdate()
+      self.context.glm.release(locking.LEVEL_CLUSTER)
+      self.exclusive_BGL = False
 
     return result
 
@@ -158,13 +199,17 @@ class Processor(object):
     if lu_class is None:
       raise errors.OpCodeUnknown("Unknown opcode")
 
+    if lu_class.REQ_BGL and not self.exclusive_BGL:
+      raise errors.ProgrammerError("LUs which require the BGL cannot"
+                                   " be chained to granular ones.")
+
     if lu_class.REQ_WSSTORE:
       sstore = ssconf.WritableSimpleStore()
     else:
       sstore = ssconf.SimpleStore()
 
     #do_hooks = lu_class.HPATH is not None
-    lu = lu_class(self, op, self.context.cfg, sstore)
+    lu = lu_class(self, op, self.context, sstore)
     lu.CheckPrereq()
     #if do_hooks:
     #  hm = HooksMaster(rpc.call_hooks_runner, self, lu)