libceph: fix linger request requeueing

Fix the request transition from linger -> normal request.  The key is to
preserve r_osd and requeue on the same OSD.  Reregister as a normal request,
add the request to the proper queues, then unregister the linger.  Fix the
unregister helper to avoid clearing r_osd (and also simplify the parallel
check in __unregister_request()).

Reported-by: Henry Chang <henry.cy.chang@gmail.com>
Signed-off-by: Sage Weil <sage@newdream.net>

1 files changed, 9 insertions, 3 deletions

diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index 3b91d651fe08..9204de484c2e 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -579,9 +579,15 @@ static void __kick_osd_requests(struct ceph_osd_client *osdc,
 
         list_for_each_entry_safe(req, nreq, &osd->o_linger_requests,
                                  r_linger_osd) {
-                __unregister_linger_request(osdc, req);
+                /*
+                 * reregister request prior to unregistering linger so
+                 * that r_osd is preserved.
+                 */
+                BUG_ON(!list_empty(&req->r_req_lru_item));
                 __register_request(osdc, req);
-                list_move(&req->r_req_lru_item, &osdc->req_unsent);
+                list_add(&req->r_req_lru_item, &osdc->req_unsent);
+                list_add(&req->r_osd_item, &req->r_osd->o_requests);
+                __unregister_linger_request(osdc, req);
                 dout("requeued lingering %p tid %llu osd%d\n", req, req->r_tid,
                      osd->o_osd);
         }
@@ -798,7 +804,7 @@ static void __register_request(struct ceph_osd_client *osdc,
         req->r_request->hdr.tid = cpu_to_le64(req->r_tid);
         INIT_LIST_HEAD(&req->r_req_lru_item);
 
-        dout("register_request %p tid %lld\n", req, req->r_tid);
+        dout("__register_request %p tid %lld\n", req, req->r_tid);
         __insert_request(osdc, req);
         ceph_osdc_get_request(req);
         osdc->num_requests++;