LU-8250 mdd: move linkea prepare out of transaction.

Move linkea prepare out of transaction to avoid reading
linkea remotely inside the transaciton.

Signed-off-by: Di Wang <di.wang@intel.com>
Change-Id: I10f0979c0c496fdcc5349f36ac5cca123d42c8a5
Reviewed-on: http://review.whamcloud.com/23096
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Mike Pershin <mike.pershin@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>

diff --git a/lustre/mdd/mdd_dir.c b/lustre/mdd/mdd_dir.c
index 975c1cb..65fd18d 100644 (file)
--- a/lustre/mdd/mdd_dir.c
+++ b/lustre/mdd/mdd_dir.c
@@ -1325,6 +1325,14 @@ static int mdd_link(const struct lu_env *env, struct md_object *tgt_obj,
        LASSERT(ma->ma_attr.la_valid & LA_CTIME);
        la->la_ctime = la->la_mtime = ma->ma_attr.la_ctime;
 
+       /* Note: even this function will change ldata, but it comes from
+        * thread_info, which is completely temporary and only seen in
+        * this function, so we do not need reset ldata once it fails.*/
+       rc = mdd_linkea_prepare(env, mdd_sobj, NULL, NULL, mdo2fid(mdd_tobj),
+                               lname, 0, 0, ldata);
+       if (rc != 0)
+               GOTO(stop, rc);
+
        rc = mdd_declare_link(env, mdd, mdd_tobj, mdd_sobj, lname, handle,
                              la, ldata);
         if (rc)
@@ -1370,17 +1378,12 @@ static int mdd_link(const struct lu_env *env, struct md_object *tgt_obj,
 
        la->la_valid = LA_CTIME;
        rc = mdd_update_time(env, mdd_sobj, cattr, la, handle);
-       if (rc == 0) {
-               rc = mdd_linkea_prepare(env, mdd_sobj, NULL, NULL,
-                                       mdo2fid(mdd_tobj), lname, 0, 0,
-                                       ldata);
-               if (rc == 0)
-                       mdd_links_add(env, mdd_sobj, mdo2fid(mdd_tobj),
-                                     lname, handle, ldata, 0);
-               /* The failure of links_add should not cause the link
-                * failure, reset rc here */
-               rc = 0;
-       }
+       if (rc == 0)
+               /* Note: The failure of links_add should not cause the
+                * link failure, so do not check return value. */
+               mdd_links_add(env, mdd_sobj, mdo2fid(mdd_tobj),
+                             lname, handle, ldata, 0);
+
        EXIT;
 out_unlock:
        mdd_write_unlock(env, mdd_sobj);