[Tarantool-patches] [PATCH 4/4] txn_limbo: add ROLLBACK processing

[Serge Petrenko]

18.06.2020 15:14, Serge Petrenko пишет:
> Now txn_limbo writes a ROLLBACK entry to WAL when one of the limbo
> entries fails to gather quorum during a txn_limbo_confirm_timeout.
> All the limbo entries, starting with the failed one, are rolled back in
> reverse order.
>
> Closes #4848


New commit:

commit 2ee0c4380f17658b0fd1a507d565cd79b6910e3d
Author: Serge Petrenko <sergepetrenko at tarantool.org>
Date:   Mon Jun 22 21:08:49 2020 +0300

     fix for 'txn_limbo: add ROLLBACK processing'

     Fix parameter use inside applier_on_rollback_written().

     Make applier_txn_rollback_cb() respect rollback reason in
     txn->signature.

     Make limbo set rollback reason after timeout or read ROLLBACK message.

     [TO BE SQUASHED INTO THE PREVIOUS COMMIT]

diff --git a/src/box/applier.cc b/src/box/applier.cc
index 98a140a57..774af0149 100644
--- a/src/box/applier.cc
+++ b/src/box/applier.cc
@@ -273,10 +273,10 @@ applier_on_confirm_written(struct trigger *trig, 
void *event)
   * Rolls back part of the txs waiting in limbo.
   */
  static int
-applier_on_rollback_written(struct trigger *trig, void *data)
+applier_on_rollback_written(struct trigger *trig, void *event)
  {
-    (void) trig;
-    int64_t lsn = *(int64_t *)data;
+    (void) event;
+    int64_t lsn = *(int64_t *)trig->data;
      txn_limbo_read_rollback(&txn_limbo, lsn);
      return 0;
  }
@@ -801,6 +801,14 @@ static int
  applier_txn_rollback_cb(struct trigger *trigger, void *event)
  {
      (void) trigger;
+    struct txn *txn = (struct txn *) event;
+    /*
+     * Synchronous transaction rollback due to receiving a
+     * ROLLBACK entry is a normal event and requires no
+     * special handling.
+     */
+    if (txn->signature == TXN_SIGNATURE_SYNC_ROLLBACK)
+        return 0;

      /*
       * Setup shared applier diagnostic area.
diff --git a/src/box/txn_limbo.c b/src/box/txn_limbo.c
index 03badf9fc..931f5c3d4 100644
--- a/src/box/txn_limbo.c
+++ b/src/box/txn_limbo.c
@@ -150,7 +150,7 @@ txn_limbo_wait_complete(struct txn_limbo *limbo, 
struct txn_limbo_entry *entry)
          rlist_foreach_entry_safe_reverse(e, &limbo->queue,
                           in_queue, tmp) {
              e->is_rollback = true;
-            e->txn->signature = -1;
+            e->txn->signature = TXN_SIGNATURE_QUORUM_TIMEOUT;
              txn_limbo_pop(limbo, e);
              txn_clear_flag(e->txn, TXN_WAIT_ACK);
              txn_complete(e->txn);
@@ -274,7 +274,7 @@ txn_limbo_read_rollback(struct txn_limbo *limbo, 
int64_t lsn)
          txn_clear_flag(e->txn, TXN_WAIT_ACK);

          /* Rollback the transaction. */
-        e->txn->signature = -1;
+        e->txn->signature = TXN_SIGNATURE_SYNC_ROLLBACK;
          txn_complete(e->txn);
      }
  }

-- 
Serge Petrenko