Merge branch 'bjorn/erts/persistent_terms/OTP-14669' into maint

* bjorn/erts/persistent_terms/OTP-14669:
  Implement a tab for persistent terms in crashdump viewer
  Add tests of persistent terms for crashdump_viewer
  Add a persistent term storage
  Refactor releasing of literals
  Extend the sharing-preserving routines to optionally copy literals

4 files changed, 64 insertions, 1 deletions

diff --git a/erts/preloaded/src/Makefile b/erts/preloaded/src/Makefile
index 4333f6643a..e768a8edbc 100644
--- a/erts/preloaded/src/Makefile
+++ b/erts/preloaded/src/Makefile
@@ -47,7 +47,8 @@ PRE_LOADED_ERL_MODULES = \
 	erts_internal \
 	erl_tracer \
 	erts_literal_area_collector \
-	erts_dirty_process_signal_handler
+	erts_dirty_process_signal_handler \
+        persistent_term
 
 PRE_LOADED_BEAM_MODULES = \
 	prim_eval
diff --git a/erts/preloaded/src/erts_internal.erl b/erts/preloaded/src/erts_internal.erl
index 88f47e917b..63b786a473 100644
--- a/erts/preloaded/src/erts_internal.erl
+++ b/erts/preloaded/src/erts_internal.erl
@@ -90,6 +90,8 @@
 
 -export([create_dist_channel/4]).
 
+-export([erase_persistent_terms/0]).
+
 %%
 %% Await result of send to port
 %%
@@ -691,3 +693,7 @@ process_flag(_Pid, _Flag, _Value) ->
                                  
 create_dist_channel(_Node, _DistCtrlr, _Flags, _Ver) ->
     erlang:nif_error(undefined).
+
+-spec erase_persistent_terms() -> 'ok'.
+erase_persistent_terms() ->
+    erlang:nif_error(undefined).
diff --git a/erts/preloaded/src/init.erl b/erts/preloaded/src/init.erl
index 253fcf7a1f..b4b8b3bf9b 100644
--- a/erts/preloaded/src/init.erl
+++ b/erts/preloaded/src/init.erl
@@ -552,6 +552,7 @@ stop(Reason,State) ->
 do_stop(restart,#state{start = Start, flags = Flags, args = Args}) ->
     %% Make sure we don't have any outstanding messages before doing the restart.
     flush(),
+    erts_internal:erase_persistent_terms(),
     boot(Start,Flags,Args);
 do_stop(reboot,_) ->
     halt();
diff --git a/erts/preloaded/src/persistent_term.erl b/erts/preloaded/src/persistent_term.erl
new file mode 100644
index 0000000000..5d0c266127
--- /dev/null
+++ b/erts/preloaded/src/persistent_term.erl
@@ -0,0 +1,55 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2018. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(persistent_term).
+
+-export([erase/1,get/0,get/1,info/0,put/2]).
+
+-type key() :: term().
+-type value() :: term().
+
+-spec erase(Key) -> Result when
+      Key :: key(),
+      Result :: boolean().
+erase(_Key) ->
+    erlang:nif_error(undef).
+
+-spec get() -> List when
+      List :: [{key(),value()}].
+get() ->
+    erlang:nif_error(undef).
+
+-spec get(Key) -> Value when
+      Key :: key(),
+      Value :: value().
+get(_Key) ->
+    erlang:nif_error(undef).
+
+-spec info() -> Info when
+      Info :: #{'count':=Count,'memory':=Memory},
+      Count :: non_neg_integer(),
+      Memory :: non_neg_integer().
+info() ->
+    erlang:nif_error(undef).
+
+-spec put(Key, Value) -> 'ok' when
+      Key :: key(),
+      Value :: value().
+put(_Key, _Value) ->
+    erlang:nif_error(undef).