[master] Don't block when evaluating requisites of parallel states

changelog/59959.fixed.md

@@ -0,0 +1 @@
+Fixed requisites by parallel states on parallel states being evaluated synchronously (blocking state execution for other parallel states)

salt/modules/state.py

@@ -1926,7 +1926,7 @@ def sls_id(id_, mods, test=None, queue=None, state_events=None, **kwargs):
         ret = {}
         for chunk in chunks:
             if chunk.get("__id__", "") == id_:
-                ret.update(st_.state.call_chunk(chunk, {}, chunks))
+                ret.update(st_.state.call_chunk(chunk, {}, chunks)[0])
 
         _set_retcode(ret, highstate=highstate)
         # Work around Windows multiprocessing bug, set __opts__['test'] back to

salt/state.py

@@ -2468,6 +2468,20 @@ def call_chunks(
         """
         Iterate over a list of chunks and call them, checking for requires.
         """
+
+        def _call_pending(
+            pending: dict[str, LowChunk], running: dict[str, dict]
+        ) -> tuple[dict[str, LowChunk], dict[str, dict], bool]:
+            still_pending = {}
+            for tag, pend in pending.items():
+                if tag not in running:
+                    running, is_pending = self.call_chunk(pend, running, chunks)
+                    if is_pending:
+                        still_pending[tag] = pend
+                    if self.check_failhard(pend, running):
+                        return still_pending, running, True
+            return still_pending, running, False
+
         if disabled_states is None:
             # Check for any disabled states
             disabled = {}
@@ -2476,7 +2490,11 @@ def call_chunks(
         else:
             disabled = disabled_states
         running = {}
+        pending_chunks = {}
         for low in chunks:
+            pending_chunks, running, failhard = _call_pending(pending_chunks, running)
+            if failhard:
+                return running
             if "__FAILHARD__" in running:
                 running.pop("__FAILHARD__")
                 return running
@@ -2486,14 +2504,21 @@ def call_chunks(
                 action = self.check_pause(low)
                 if action == "kill":
                     break
-                running = self.call_chunk(low, running, chunks)
+                running, pending = self.call_chunk(low, running, chunks)
+                if pending:
+                    pending_chunks[tag] = low
                 if self.check_failhard(low, running):
                     return running
+        while pending_chunks:
+            pending_chunks, running, failhard = _call_pending(pending_chunks, running)
+            if failhard:
+                return running
+            time.sleep(0.01)
         while True:
             if self.reconcile_procs(running):
                 break
             time.sleep(0.01)
-        ret = dict(list(disabled.items()) + list(running.items()))
+        ret = {**disabled, **running}
         return ret
 
     def check_failhard(self, low: LowChunk, running: dict[str, dict]):
@@ -2599,6 +2624,7 @@ def _check_requisites(self, low: LowChunk, running: dict[str, dict[str, Any]]):
         states.
         """
         reqs = {}
+        pending = False
         for req_type, chunk in self.dependency_dag.get_dependencies(low):
             reqs.setdefault(req_type, []).append(chunk)
         fun_stats = set()
@@ -2617,17 +2643,15 @@ def _check_requisites(self, low: LowChunk, running: dict[str, dict[str, Any]]):
                 if run_dict_chunk:
                     filtered_run_dict[tag] = run_dict_chunk
             run_dict = filtered_run_dict
-
-            while True:
-                if self.reconcile_procs(run_dict):
-                    break
-                time.sleep(0.01)
+            pending = bool(not self.reconcile_procs(run_dict) and low.get("parallel"))
 
             for chunk in chunks:
                 tag = _gen_tag(chunk)
                 if tag not in run_dict:
                     req_stats.add("unmet")
                     continue
+                if pending:
+                    continue
                 # A state can include a "skip_req" key in the return dict
                 # with a True value to skip triggering onchanges, watch, or
                 # other requisites which would result in a only running on a
@@ -2684,6 +2708,8 @@ def _check_requisites(self, low: LowChunk, running: dict[str, dict[str, Any]]):
 
         if "unmet" in fun_stats:
             status = "unmet"
+        elif pending:
+            status = "pending"
         elif "fail" in fun_stats:
             status = "fail"
         elif "skip_req" in fun_stats and (fun_stats & {"onchangesmet", "premet"}):
@@ -2765,7 +2791,7 @@ def call_chunk(
         running: dict[str, dict],
         chunks: Sequence[LowChunk],
         depth: int = 0,
-    ) -> dict[str, dict]:
+    ) -> tuple[dict[str, dict], bool]:
         """
         Execute the chunk if the requisites did not fail
         """
@@ -2781,8 +2807,13 @@ def call_chunk(
 
         status, reqs = self._check_requisites(low, running)
         if status == "unmet":
-            if self._call_unmet_requisites(low, running, chunks, tag, depth):
-                return running
+            running_failhard, pending = self._call_unmet_requisites(
+                low, running, chunks, tag, depth
+            )
+            if running_failhard or pending:
+                return running, pending
+        elif status == "pending":
+            return running, True
         elif status == "met":
             if low.get("__prereq__"):
                 self.pre[tag] = self.call(low, chunks, running)
@@ -2910,7 +2941,7 @@ def call_chunk(
                 for key in ("__sls__", "__id__", "name"):
                     running[sub_tag][key] = low.get(key)
 
-        return running
+        return running, False
 
     def _assign_not_run_result_dict(
         self,
@@ -2944,16 +2975,19 @@ def _call_unmet_requisites(
         chunks: Sequence[LowChunk],
         tag: str,
         depth: int,
-    ) -> dict[str, dict]:
+    ) -> tuple[dict[str, dict], bool]:
+        pending = False
         for _, chunk in self.dependency_dag.get_dependencies(low):
             # Check to see if the chunk has been run, only run it if
             # it has not been run already
             ctag = _gen_tag(chunk)
             if ctag not in running:
-                running = self.call_chunk(chunk, running, chunks)
+                running, pending = self.call_chunk(chunk, running, chunks)
+                if pending:
+                    return running, pending
                 if self.check_failhard(chunk, running):
                     running["__FAILHARD__"] = True
-                    return running
+                    return running, pending
         if low.get("__prereq__"):
             status, _ = self._check_requisites(low, running)
             self.pre[tag] = self.call(low, chunks, running)
@@ -2975,11 +3009,11 @@ def _call_unmet_requisites(
                 for key in ("__sls__", "__id__", "name"):
                     running[tag][key] = low.get(key)
             else:
-                running = self.call_chunk(low, running, chunks, depth)
+                running, pending = self.call_chunk(low, running, chunks, depth)
         if self.check_failhard(low, running):
             running["__FAILHARD__"] = True
-            return running
-        return {}
+            return running, pending
+        return {}, pending
 
     def call_beacons(self, chunks: Iterable[LowChunk], running: dict) -> dict:
         """

tests/pytests/functional/modules/state/requisites/test_require.py

@@ -1,3 +1,4 @@
+import datetime
 import time
 
 import pytest
@@ -537,6 +538,69 @@ def test_parallel_state_with_requires(state, state_tree):
             assert "__parallel__" in ret[_id]
 
 
+@pytest.mark.skip_on_windows
+def test_parallel_state_with_requires_on_parallel(state, state_tree):
+    """
+    Parallel states requiring other parallel states should not block
+    state execution while waiting on their requisites.
+
+    Issue #59959
+    """
+    sls_contents = """
+        service_a:
+          cmd.run:
+              - name: sleep 2
+              - parallel: True
+
+        service_b1:
+          cmd.run:
+              - name: sleep 5
+              - parallel: True
+              - require:
+                  - service_a
+
+        service_b2:
+          cmd.run:
+              - name: 'true'
+              - parallel: True
+              - require:
+                  - service_b1
+
+        service_c:
+          cmd.run:
+              - name: 'true'
+              - parallel: True
+              - require:
+                  - service_a
+    """
+
+    with pytest.helpers.temp_file("requisite_parallel.sls", sls_contents, state_tree):
+        ret = state.sls(
+            "requisite_parallel",
+            __pub_jid="1",  # Because these run in parallel we need a fake JID)
+        )
+        start_b1 = datetime.datetime.combine(
+            datetime.date.today(),
+            datetime.time.fromisoformat(
+                ret["cmd_|-service_b1_|-sleep 5_|-run"]["start_time"]
+            ),
+        )
+        start_c = datetime.datetime.combine(
+            datetime.date.today(),
+            datetime.time.fromisoformat(
+                ret["cmd_|-service_c_|-true_|-run"]["start_time"]
+            ),
+        )
+        start_diff = start_c - start_b1
+        # Expected order:
+        #   a > (b1, c) > b2
+        # When b2 blocks while waiting for b1, c has to wait for b1 as well.
+        # c should approximately start at the same time as b1 though.
+        assert start_diff < datetime.timedelta(seconds=5)  # b1 sleeps for 5 seconds
+        for state_ret in ret.raw.values():
+            assert "__parallel__" in state_ret
+
+
 def test_issue_59922_conflict_in_name_and_id_for_require_in(state, state_tree):
     """
     Make sure that state_type is always honored while compiling down require_in to

tests/pytests/unit/modules/state/test_state.py

@@ -107,7 +107,7 @@ def call_chunk(data, data1, data2):
             """
             Mock call_chunk method
             """
-            return {"": "ABC"}
+            return {"": "ABC"}, False
 
         @staticmethod
         def call_chunks(data):

tests/pytests/unit/state/test_state_compiler.py

@@ -853,7 +853,7 @@ def test_call_chunk_sub_state_run(minion_opts):
         with patch("salt.state.State.call", return_value=mock_call_return):
             minion_opts["disabled_requisites"] = ["require"]
             state_obj = salt.state.State(minion_opts)
-            ret = state_obj.call_chunk(low_data, {}, [])
+            ret, _ = state_obj.call_chunk(low_data, {}, [])
             sub_state = ret.get(expected_sub_state_tag)
             assert sub_state
             assert sub_state["__run_num__"] == 1