diff --git a/infer/src/absint/AbstractInterpreter.ml b/infer/src/absint/AbstractInterpreter.ml
index 8b733d1bd..3922a3a29 100644
--- a/infer/src/absint/AbstractInterpreter.ml
+++ b/infer/src/absint/AbstractInterpreter.ml
@@ -304,9 +304,16 @@ module AbstractInterpreterCommon (TransferFunctions : NodeTransferFunctions) = s
       | Ok post ->
           post
       | Error (exn, backtrace, instr) ->
-          if not !logged_error then (
-            L.internal_error "In instruction %a@\n" (Sil.pp_instr ~print_types:true Pp.text) instr ;
-            logged_error := true ) ;
+          ( match exn with
+          | TaskSchedulerTypes.ProcnameAlreadyLocked _ ->
+              (* this isn't an error; don't log it *)
+              ()
+          | _ ->
+              if not !logged_error then (
+                L.internal_error "In instruction %a@\n"
+                  (Sil.pp_instr ~print_types:true Pp.text)
+                  instr ;
+                logged_error := true ) ) ;
           Caml.Printexc.raise_with_backtrace exn backtrace
     in
     (* hack to ensure that we call `exec_instr` on a node even if it has no instructions *)
diff --git a/infer/src/backend/SchedulerTypes.ml b/infer/src/absint/TaskSchedulerTypes.ml
similarity index 59%
rename from infer/src/backend/SchedulerTypes.ml
rename to infer/src/absint/TaskSchedulerTypes.ml
index 679ec3bb4..4550df667 100644
--- a/infer/src/backend/SchedulerTypes.ml
+++ b/infer/src/absint/TaskSchedulerTypes.ml
@@ -6,4 +6,8 @@
  *)
 open! IStd
 
+exception ProcnameAlreadyLocked of Procname.t
+(** for the Restart scheduler: raise when a worker tries to analyze a procedure already being
+    analyzed by another process *)
+
 type target = Procname of Procname.t | File of SourceFile.t
diff --git a/infer/src/backend/FileScheduler.ml b/infer/src/backend/FileScheduler.ml
index 705902159..ec6a0bc70 100644
--- a/infer/src/backend/FileScheduler.ml
+++ b/infer/src/backend/FileScheduler.ml
@@ -7,7 +7,7 @@
 open! IStd
 
 let make sources =
-  let open SchedulerTypes in
+  let open TaskSchedulerTypes in
   let gen =
     List.rev_map sources ~f:(fun sf -> File sf)
     |> List.permute ~random_state:(Random.State.make (Array.create ~len:1 0))
diff --git a/infer/src/backend/FileScheduler.mli b/infer/src/backend/FileScheduler.mli
index 32ba8fc52..945815b23 100644
--- a/infer/src/backend/FileScheduler.mli
+++ b/infer/src/backend/FileScheduler.mli
@@ -6,4 +6,4 @@
  *)
 open! IStd
 
-val make : SourceFile.t list -> (SchedulerTypes.target, Procname.t) ProcessPool.TaskGenerator.t
+val make : SourceFile.t list -> (TaskSchedulerTypes.target, Procname.t) ProcessPool.TaskGenerator.t
diff --git a/infer/src/backend/InferAnalyze.ml b/infer/src/backend/InferAnalyze.ml
index eed1961fe..c1c17c04e 100644
--- a/infer/src/backend/InferAnalyze.ml
+++ b/infer/src/backend/InferAnalyze.ml
@@ -19,7 +19,7 @@ let clear_caches_except_lrus () =
 
 let clear_caches () = Ondemand.LocalCache.clear () ; clear_caches_except_lrus ()
 
-let analyze_target : (SchedulerTypes.target, Procname.t) Tasks.doer =
+let analyze_target : (TaskSchedulerTypes.target, Procname.t) Tasks.doer =
   let analyze_source_file exe_env source_file =
     if Topl.is_active () then DB.Results_dir.init (Topl.sourcefile ()) ;
     DB.Results_dir.init source_file ;
@@ -30,7 +30,7 @@ let analyze_target : (SchedulerTypes.target, Procname.t) Tasks.doer =
             DotCfg.emit_frontend_cfg (Topl.sourcefile ()) (Topl.cfg ()) ;
           if Config.write_html then Printer.write_all_html_files source_file ;
           None
-        with RestartScheduler.ProcnameAlreadyLocked pname -> Some pname )
+        with TaskSchedulerTypes.ProcnameAlreadyLocked pname -> Some pname )
   in
   (* In call-graph scheduling, log progress every [per_procedure_logging_granularity] procedures.
      The default roughly reflects the average number of procedures in a C++ file. *)
@@ -46,7 +46,7 @@ let analyze_target : (SchedulerTypes.target, Procname.t) Tasks.doer =
     try
       Ondemand.analyze_proc_name_toplevel exe_env proc_name ;
       None
-    with RestartScheduler.ProcnameAlreadyLocked pname -> Some pname
+    with TaskSchedulerTypes.ProcnameAlreadyLocked pname -> Some pname
   in
   fun target ->
     let exe_env = Exe_env.mk () in
@@ -124,7 +124,9 @@ let tasks_generator_builder_for sources =
 
 let analyze source_files_to_analyze =
   if Int.equal Config.jobs 1 then (
-    let target_files = List.rev_map source_files_to_analyze ~f:(fun sf -> SchedulerTypes.File sf) in
+    let target_files =
+      List.rev_map source_files_to_analyze ~f:(fun sf -> TaskSchedulerTypes.File sf)
+    in
     Tasks.run_sequentially ~f:analyze_target target_files ;
     BackendStats.get () )
   else (
diff --git a/infer/src/backend/RestartScheduler.ml b/infer/src/backend/RestartScheduler.ml
index 1de82be57..b745b96f6 100644
--- a/infer/src/backend/RestartScheduler.ml
+++ b/infer/src/backend/RestartScheduler.ml
@@ -7,9 +7,7 @@
 open! IStd
 module L = Logging
 
-exception ProcnameAlreadyLocked of Procname.t
-
-type work_with_dependency = {work: SchedulerTypes.target; need_to_finish: Procname.t option}
+type work_with_dependency = {work: TaskSchedulerTypes.target; need_to_finish: Procname.t option}
 
 let of_list (lst : work_with_dependency list) : ('a, Procname.t) ProcessPool.TaskGenerator.t =
   let content = Queue.of_list lst in
@@ -39,10 +37,10 @@ let make sources =
     List.map sources ~f:SourceFiles.proc_names_of_source
     |> List.concat
     |> List.rev_map ~f:(fun procname ->
-           {work= SchedulerTypes.Procname procname; need_to_finish= None} )
+           {work= TaskSchedulerTypes.Procname procname; need_to_finish= None} )
   in
   let files =
-    List.map sources ~f:(fun file -> {work= SchedulerTypes.File file; need_to_finish= None})
+    List.map sources ~f:(fun file -> {work= TaskSchedulerTypes.File file; need_to_finish= None})
   in
   let permute = List.permute ~random_state:(Random.State.make (Array.create ~len:1 0)) in
   permute pnames @ permute files |> of_list
@@ -91,7 +89,7 @@ let lock_exn pname =
       if ProcLocker.try_lock pname then record_locked_proc pname
       else (
         unlock_all () ;
-        raise (ProcnameAlreadyLocked pname) ) )
+        raise (TaskSchedulerTypes.ProcnameAlreadyLocked pname) ) )
 
 
 let unlock pname =
diff --git a/infer/src/backend/RestartScheduler.mli b/infer/src/backend/RestartScheduler.mli
index 9054c85be..79f08e1d3 100644
--- a/infer/src/backend/RestartScheduler.mli
+++ b/infer/src/backend/RestartScheduler.mli
@@ -6,8 +6,6 @@
  *)
 open! IStd
 
-exception ProcnameAlreadyLocked of Procname.t
-
 val setup : unit -> unit
 
 val clean : unit -> unit
@@ -16,4 +14,4 @@ val lock_exn : Procname.t -> unit
 
 val unlock : Procname.t -> unit
 
-val make : SourceFile.t list -> (SchedulerTypes.target, Procname.t) ProcessPool.TaskGenerator.t
+val make : SourceFile.t list -> (TaskSchedulerTypes.target, Procname.t) ProcessPool.TaskGenerator.t
diff --git a/infer/src/backend/SyntacticCallGraph.ml b/infer/src/backend/SyntacticCallGraph.ml
index a400b65f7..d9d75861c 100644
--- a/infer/src/backend/SyntacticCallGraph.ml
+++ b/infer/src/backend/SyntacticCallGraph.ml
@@ -96,8 +96,8 @@ let build_from_sources sources =
   g
 
 
-let bottom_up sources : (SchedulerTypes.target, Procname.t) ProcessPool.TaskGenerator.t =
-  let open SchedulerTypes in
+let bottom_up sources : (TaskSchedulerTypes.target, Procname.t) ProcessPool.TaskGenerator.t =
+  let open TaskSchedulerTypes in
   let syntactic_call_graph = build_from_sources sources in
   let remaining = ref (CallGraph.n_procs syntactic_call_graph) in
   let remaining_tasks () = !remaining in
diff --git a/infer/src/backend/SyntacticCallGraph.mli b/infer/src/backend/SyntacticCallGraph.mli
index 1c6dff799..8cc758d43 100644
--- a/infer/src/backend/SyntacticCallGraph.mli
+++ b/infer/src/backend/SyntacticCallGraph.mli
@@ -6,7 +6,7 @@
  *)
 open! IStd
 
-val make : SourceFile.t list -> (SchedulerTypes.target, Procname.t) ProcessPool.TaskGenerator.t
+val make : SourceFile.t list -> (TaskSchedulerTypes.target, Procname.t) ProcessPool.TaskGenerator.t
 (** task generator that works by
 
     - loading the syntactic call graph from the capture DB
diff --git a/infer/src/backend/ondemand.ml b/infer/src/backend/ondemand.ml
index 9d11d2b1a..6c7858a24 100644
--- a/infer/src/backend/ondemand.ml
+++ b/infer/src/backend/ondemand.ml
@@ -223,7 +223,7 @@ let run_proc_analysis ~caller_pdesc callee_pdesc =
     let backtrace = Printexc.get_backtrace () in
     IExn.reraise_if exn ~f:(fun () ->
         match exn with
-        | RestartScheduler.ProcnameAlreadyLocked _ ->
+        | TaskSchedulerTypes.ProcnameAlreadyLocked _ ->
             clear_actives () ; restore_global_state old_state ; true
         | _ ->
             if not !logged_error then (