SERVER-15535 Consider return value of setFollowerMode in call sites that care.

3 files changed, 15 insertions, 6 deletions

diff --git a/src/mongo/db/repl/resync.cpp b/src/mongo/db/repl/resync.cpp
index 915ab0e440b..a1703987676 100644
--- a/src/mongo/db/repl/resync.cpp
+++ b/src/mongo/db/repl/resync.cpp
@@ -75,12 +75,11 @@ namespace repl {
                     return appendCommandStatus(result, Status(ErrorCodes::NotYetInitialized,
                                                               "no replication yet active"));
                 }
-                if (replCoord->getCurrentMemberState().primary()) {
+                if (replCoord->getCurrentMemberState().primary() ||
+                        !replCoord->setFollowerMode(MemberState::RS_STARTUP2)) {
                     return appendCommandStatus(result, Status(ErrorCodes::NotSecondary,
                                                               "primaries cannot resync"));
                 }
-
-                replCoord->setFollowerMode(MemberState::RS_STARTUP2);
                 BackgroundSync::get()->setInitialSyncRequestedFlag(true);
                 return true;
             }
diff --git a/src/mongo/db/repl/rs_rollback.cpp b/src/mongo/db/repl/rs_rollback.cpp
index 97cafc3d849..ff3c8db959a 100644
--- a/src/mongo/db/repl/rs_rollback.cpp
+++ b/src/mongo/db/repl/rs_rollback.cpp
@@ -730,7 +730,11 @@ namespace {
          *
          *  also, this is better for status reporting - we know what is happening.
          */
-        replCoord->setFollowerMode(MemberState::RS_ROLLBACK);
+        if (!replCoord->setFollowerMode(MemberState::RS_ROLLBACK)) {
+            log() << "Cannot transition from " << replCoord->getCurrentMemberState() << " to " <<
+                MemberState(MemberState::RS_ROLLBACK);
+            return 0;
+        }
 
         FixUpInfo how;
         log() << "rollback 1";
@@ -778,7 +782,11 @@ namespace {
 
         // success - leave "ROLLBACK" state
         // can go to SECONDARY once minvalid is achieved
-        replCoord->setFollowerMode(MemberState::RS_RECOVERING);
+        if (!replCoord->setFollowerMode(MemberState::RS_RECOVERING)) {
+            warning() << "Failed to transition into " << MemberState(MemberState::RS_RECOVERING) <<
+                "; expected to be in state " << MemberState(MemberState::RS_ROLLBACK) <<
+                "but found self in " << replCoord->getCurrentMemberState();
+        }
 
         return 0;
     }
diff --git a/src/mongo/db/repl/rs_sync.cpp b/src/mongo/db/repl/rs_sync.cpp
index ec31acb65c0..839bae2e188 100644
--- a/src/mongo/db/repl/rs_sync.cpp
+++ b/src/mongo/db/repl/rs_sync.cpp
@@ -213,7 +213,9 @@ namespace repl {
                     syncDoInitialSync();
                     continue; // start from top again in case sync failed.
                 }
-                replCoord->setFollowerMode(MemberState::RS_RECOVERING);
+                if (!replCoord->setFollowerMode(MemberState::RS_RECOVERING)) {
+                    continue;
+                }
 
                 /* we have some data.  continue tailing. */
                 SyncTail tail(BackgroundSync::get(), multiSyncApply);