libaio: don't call io_destroy(), let exit_aio() take care of it

From the exit_aio() path, we can parallellize the freeing, hence
not taking an RCU grace period hit for each.

Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/engines/libaio.c b/engines/libaio.c
index d4f48303becb8af99a63bcc0e1667a030bdd0a66..8ba21f8959b318939786aaa21b96e21f7485d8c5 100644 (file)
--- a/engines/libaio.c
+++ b/engines/libaio.c
@@ -316,7 +316,14 @@ static void fio_libaio_cleanup(struct thread_data *td)
        struct libaio_data *ld = td->io_ops->data;
 
        if (ld) {
-               io_destroy(ld->aio_ctx);
+               /*
+                * Work-around to avoid huge RCU stalls at exit time. If we
+                * don't do this here, then it'll be torn down by exit_aio().
+                * But for that case we can parallellize the freeing, thus
+                * speeding it up a lot.
+                */
+               if (!(td->flags & TD_F_CHILD))
+                       io_destroy(ld->aio_ctx);
                free(ld->aio_events);
                free(ld->iocbs);
                free(ld->io_us);