Fix txg_quiesce thread deadlock

[zfs.git] / module / zfs / txg.c

diff --git a/module/zfs/txg.c b/module/zfs/txg.c
index c7c3df3..7c820af 100644 (file)
--- a/module/zfs/txg.c
+++ b/module/zfs/txg.c
@@ -367,6 +367,13 @@ txg_quiesce(dsl_pool_t *dp, uint64_t txg)
        tx->tx_open_txg++;
 
        /*
+        * Now that we've incremented tx_open_txg, we can let threads
+        * enter the next transaction group.
+        */
+       for (c = 0; c < max_ncpus; c++)
+               mutex_exit(&tx->tx_cpu[c].tc_lock);
+
+       /*
         * Measure how long the txg was open and replace the kstat.
         */
        th = dsl_pool_txg_history_get(dp, txg);
@@ -376,13 +383,6 @@ txg_quiesce(dsl_pool_t *dp, uint64_t txg)
        dsl_pool_txg_history_add(dp, tx->tx_open_txg);
 
        /*
-        * Now that we've incremented tx_open_txg, we can let threads
-        * enter the next transaction group.
-        */
-       for (c = 0; c < max_ncpus; c++)
-               mutex_exit(&tx->tx_cpu[c].tc_lock);
-
-       /*
         * Quiesce the transaction group by waiting for everyone to txg_exit().
         */
        start = gethrtime();