LU-12616 obclass: fix MDS start/stop race

[fs/lustre-release.git] / lustre / fld / fld_request.c

diff --git a/lustre/fld/fld_request.c b/lustre/fld/fld_request.c
index 123bc97..3dd616e 100644 (file)
--- a/lustre/fld/fld_request.c
+++ b/lustre/fld/fld_request.c
@@ -346,7 +346,6 @@ int fld_client_rpc(struct obd_export *exp,
 
        LASSERT(exp != NULL);
 
-again:
        imp = class_exp2cliimp(exp);
        switch (fld_op) {
        case FLD_QUERY:
@@ -397,9 +396,15 @@ again:
        req->rq_reply_portal = MDC_REPLY_PORTAL;
        ptlrpc_at_set_req_timeout(req);
 
-       obd_get_request_slot(&exp->exp_obd->u.cli);
-       rc = ptlrpc_queue_wait(req);
-       obd_put_request_slot(&exp->exp_obd->u.cli);
+       if (OBD_FAIL_CHECK(OBD_FAIL_FLD_QUERY_REQ && req->rq_no_delay)) {
+               /* the same error returned by ptlrpc_import_delay_req */
+               rc = -EWOULDBLOCK;
+               req->rq_status = rc;
+       } else {
+               obd_get_request_slot(&exp->exp_obd->u.cli);
+               rc = ptlrpc_queue_wait(req);
+               obd_put_request_slot(&exp->exp_obd->u.cli);
+       }
 
        if (rc == -ENOENT) {
                /* Don't loop forever on non-existing FID sequences. */
@@ -413,15 +418,10 @@ again:
                    OCD_HAS_FLAG(&imp->imp_connect_data, LIGHTWEIGHT) &&
                    rc != -ENOTSUPP) {
                        /*
-                        * Since LWP is not replayable, so it will keep
-                        * trying unless umount happens or the remote
-                        * target does not support the operation, otherwise
-                        * it would cause unecessary failure of the
-                        * application.
+                        * Since LWP is not replayable, so notify the caller
+                        * to retry if needed after a while.
                         */
-                       ptlrpc_req_finished(req);
-                       rc = 0;
-                       goto again;
+                       rc = -EAGAIN;
                }
                GOTO(out_req, rc);
        }