crimson/.../snaptrim_event: SnapTrimObjSubEvent should enter WaitRepop

Otherwise, it parks on Process until the repop completes blocking any
other repops, including client IO.  Since we don't actually care about
ordering, simply calling handle.complete() would also be viable, but
this is a valid usage of the stage and does provide information to an
operator.

Signed-off-by: Samuel Just <[email protected]>

Author: athanatos

src/crimson/osd/osd_operations/client_request.h

@@ -53,9 +53,6 @@ class ClientRequest final : public PhasedOperationT<ClientRequest>,
     struct AwaitMap : OrderedExclusivePhaseT<AwaitMap> {
       static constexpr auto type_name = "ClientRequest::PGPipeline::await_map";
     } await_map;
-    struct WaitRepop : OrderedConcurrentPhaseT<WaitRepop> {
-      static constexpr auto type_name = "ClientRequest::PGPipeline::wait_repop";
-    } wait_repop;
     struct SendReply : OrderedExclusivePhaseT<SendReply> {
       static constexpr auto type_name = "ClientRequest::PGPipeline::send_reply";
     } send_reply;

src/crimson/osd/osd_operations/common/pg_pipeline.h

@@ -29,6 +29,9 @@ class CommonPGPipeline {
   struct Process : OrderedExclusivePhaseT<Process> {
     static constexpr auto type_name = "CommonPGPipeline::process";
   } process;
+  struct WaitRepop : OrderedConcurrentPhaseT<WaitRepop> {
+    static constexpr auto type_name = "ClientRequest::PGPipeline::wait_repop";
+  } wait_repop;
 };
 
 } // namespace crimson::osd

src/crimson/osd/osd_operations/snaptrim_event.cc

@@ -416,8 +416,12 @@ SnapTrimObjSubEvent::start()
 	      std::move(osd_op_p),
 	      std::move(log_entries));
 	    return submitted.then_interruptible(
-	      [all_completed=std::move(all_completed), this] () mutable {
-		return std::move(all_completed);
+	      [this, all_completed=std::move(all_completed)]() mutable {
+		return enter_stage<interruptor>(
+		  client_pp().wait_repop
+		).then_interruptible([all_completed=std::move(all_completed)]() mutable{
+		  return std::move(all_completed);
+		});
 	      });
 	  });
 	});

src/crimson/osd/osd_operations/snaptrim_event.h

@@ -168,6 +168,7 @@ class SnapTrimObjSubEvent : public PhasedOperationT<SnapTrimObjSubEvent> {
     StartEvent,
     CommonPGPipeline::GetOBC::BlockingEvent,
     CommonPGPipeline::Process::BlockingEvent,
+    CommonPGPipeline::WaitRepop::BlockingEvent,
     CompletionEvent
   > tracking_events;
 };