use SpinLock

stdlib/Distributed/src/cluster.jl

@@ -95,7 +95,7 @@ end
 @enum WorkerState W_CREATED W_CONNECTED W_TERMINATING W_TERMINATED
 mutable struct Worker
  id::Int
- msg_lock::Threads.ReentrantLock # Lock for del_msgs, add_msgs, and gcflag
+ msg_lock::Threads.SpinLock # Lock for del_msgs, add_msgs, and gcflag, SpinLock since it needs to be used from finalizers
  del_msgs::Array{Any,1}
  add_msgs::Array{Any,1}
  gcflag::Bool
@@ -134,7 +134,7 @@ mutable struct Worker
  if haskey(map_pid_wrkr, id)
  return map_pid_wrkr[id]
  end
- w=new(id, Threads.ReentrantLock(), [], [], false, W_CREATED, Threads.Condition(), time(), conn_func)
+ w=new(id, Threads.SpinLock(), [], [], false, W_CREATED, Threads.Condition(), time(), conn_func)
  w.initialized = Event()
  register_worker(w)
  w

stdlib/Distributed/src/remotecall.jl

@@ -266,14 +266,13 @@ function send_del_client(rr)
  elseif id_in_procs(rr.where) # process only if a valid worker
  w = worker_from_id(rr.where)
  msg = (remoteref_id(rr), myid())
- Threads.@spawn begin # Need to spawn task since we can be in finalizer
- lock(w.msg_lock) do
- push!(w.del_msgs, $msg)
- w.gcflag = true
- end
- lock(any_gc_flag) do
- notify(any_gc_flag)
- end
+ # Lock is SpinLock an can thus be acquired from finalizer
+ lock(w.msg_lock) do
+ push!(w.del_msgs, msg)
+ w.gcflag = true
+ end
+ lock(any_gc_flag) do
+ notify(any_gc_flag)
  end
  end
 end