From e183a10c8c4d8d1a8b69b596d0c97d7365e1ec86 Mon Sep 17 00:00:00 2001
From: Jingyu Zhou <jingyuzhou@gmail.com>
Date: Tue, 20 Oct 2020 22:48:53 -0700
Subject: [PATCH] Add "waitForDestUID" flag for abortBackup

---
 fdbclient/BackupAgent.actor.h                       |  3 ++-
 fdbclient/DatabaseBackupAgent.actor.cpp             | 10 ++++++----
 fdbserver/workloads/BackupToDBCorrectness.actor.cpp |  8 +++++---
 3 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/fdbclient/BackupAgent.actor.h b/fdbclient/BackupAgent.actor.h
index 0037541cef..aa7e56f140 100644
--- a/fdbclient/BackupAgent.actor.h
+++ b/fdbclient/BackupAgent.actor.h
@@ -428,7 +428,8 @@ public:
 		return runRYWTransaction(cx, [=](Reference<ReadYourWritesTransaction> tr){ return discontinueBackup(tr, tagName); });
 	}
 
-	Future<Void> abortBackup(Database cx, Key tagName, bool partial = false, bool abortOldBackup = false, bool dstOnly = false);
+	Future<Void> abortBackup(Database cx, Key tagName, bool partial = false, bool abortOldBackup = false,
+	                         bool dstOnly = false, bool waitForDestUID = false);
 
 	Future<std::string> getStatus(Database cx, int errorLimit, Key tagName);
 
diff --git a/fdbclient/DatabaseBackupAgent.actor.cpp b/fdbclient/DatabaseBackupAgent.actor.cpp
index a829f488bb..13d1567b1c 100644
--- a/fdbclient/DatabaseBackupAgent.actor.cpp
+++ b/fdbclient/DatabaseBackupAgent.actor.cpp
@@ -2098,7 +2098,8 @@ public:
 		return Void();
 	}
 
-	ACTOR static Future<Void> abortBackup(DatabaseBackupAgent* backupAgent, Database cx, Key tagName, bool partial, bool abortOldBackup, bool dstOnly) {
+	ACTOR static Future<Void> abortBackup(DatabaseBackupAgent* backupAgent, Database cx, Key tagName, bool partial,
+	                                      bool abortOldBackup, bool dstOnly, bool waitForDestUID) {
 		state Reference<ReadYourWritesTransaction> tr(new ReadYourWritesTransaction(cx));
 		state Key logUidValue, destUidValue;
 		state UID logUid, destUid;
@@ -2125,7 +2126,7 @@ public:
 				UID destUid = destUidFuture.get();
 				if (destUid.isValid()) {
 					destUidValue = BinaryWriter::toValue(destUid, Unversioned());
-				} else if (destUidValue.size() == 0) {
+				} else if (destUidValue.size() == 0 && waitForDestUID) {
 					// Give DR task a chance to update destUid to avoid the problem of
 					// leftover version key. If we got an commit_unknown_result before,
 					// reuse the previous destUidValue.
@@ -2459,8 +2460,9 @@ Future<Void> DatabaseBackupAgent::discontinueBackup(Reference<ReadYourWritesTran
 	return DatabaseBackupAgentImpl::discontinueBackup(this, tr, tagName);
 }
 
-Future<Void> DatabaseBackupAgent::abortBackup(Database cx, Key tagName, bool partial, bool abortOldBackup, bool dstOnly){
-	return DatabaseBackupAgentImpl::abortBackup(this, cx, tagName, partial, abortOldBackup, dstOnly);
+Future<Void> DatabaseBackupAgent::abortBackup(Database cx, Key tagName, bool partial, bool abortOldBackup, bool dstOnly,
+                                              bool waitForDestUID) {
+	return DatabaseBackupAgentImpl::abortBackup(this, cx, tagName, partial, abortOldBackup, dstOnly, waitForDestUID);
 }
 
 Future<std::string> DatabaseBackupAgent::getStatus(Database cx, int errorLimit, Key tagName) {
diff --git a/fdbserver/workloads/BackupToDBCorrectness.actor.cpp b/fdbserver/workloads/BackupToDBCorrectness.actor.cpp
index 5cba973c16..2f08e2d1bf 100644
--- a/fdbserver/workloads/BackupToDBCorrectness.actor.cpp
+++ b/fdbserver/workloads/BackupToDBCorrectness.actor.cpp
@@ -545,9 +545,11 @@ struct BackupToDBCorrectnessWorkload : TestWorkload {
 
 				TraceEvent("BARW_AbortBackupExtra", randomID).detail("BackupTag", printable(self->backupTag));
 				try {
-					wait(backupAgent.abortBackup(self->extraDB, self->backupTag));
-				}
-				catch (Error& e) {
+					// This abort can race with submitBackup such that destUID may
+					// not be set yet. Adding "waitForDestUID" flag to avoid the race.
+					wait(backupAgent.abortBackup(self->extraDB, self->backupTag, /*partial=*/false,
+					                             /*abortOldBackup=*/false, /*dstOnly=*/false, /*waitForDestUID*/ true));
+				} catch (Error& e) {
 					TraceEvent("BARW_AbortBackupExtraException", randomID).error(e);
 					if (e.code() != error_code_backup_unneeded)
 						throw;