LU-11359 mdt: fix mdt_dom_discard_data() timeouts

[fs/lustre-release.git] / lustre / mdt / mdt_reint.c

diff --git a/lustre/mdt/mdt_reint.c b/lustre/mdt/mdt_reint.c
index c97e718..fdb9798 100644 (file)
--- a/lustre/mdt/mdt_reint.c
+++ b/lustre/mdt/mdt_reint.c
@@ -844,7 +844,7 @@ static int mdt_reint_unlink(struct mdt_thread_info *info,
        struct mdt_lock_handle *child_lh;
        struct ldlm_enqueue_info *einfo = &info->mti_einfo[0];
        __u64 lock_ibits;
-       bool cos_incompat = false, discard = false;
+       bool cos_incompat = false;
        int no_name = 0;
        int rc;
 
@@ -1025,8 +1025,8 @@ relock:
                rc = mdt_attr_get_complex(info, mc, ma);
                if (rc)
                        GOTO(out_stat, rc);
-       } else {
-               discard = mdt_dom_check_for_discard(info, mc);
+       } else if (mdt_dom_check_for_discard(info, mc)) {
+               mdt_dom_discard_data(info, mc);
        }
        mdt_handle_last_unlink(info, mc, ma);
 
@@ -1060,13 +1060,6 @@ unlock_parent:
        mdt_object_unlock(info, mp, parent_lh, rc);
 put_parent:
        mdt_object_put(info->mti_env, mp);
-
-       /* discard is just a PW DOM lock to drop the data on a client
-        * no need to keep objects being get and locked, do that after all.
-        */
-       if (discard)
-               mdt_dom_discard_data(info, child_fid);
-
         return rc;
 }
 
@@ -2295,8 +2288,8 @@ static int mdt_reint_rename(struct mdt_thread_info *info,
        struct lu_fid *old_fid = &info->mti_tmp_fid1;
        struct lu_fid *new_fid = &info->mti_tmp_fid2;
        __u64 lock_ibits;
-       bool reverse = false;
-       bool cos_incompat, discard = false;
+       bool reverse = false, discard = false;
+       bool cos_incompat;
        int rc;
        ENTRY;
 
@@ -2619,7 +2612,6 @@ relock:
                        mdt_handle_last_unlink(info, mnew, ma);
                        discard = mdt_dom_check_for_discard(info, mnew);
                }
-
                mdt_rename_counter_tally(info, info->mti_mdt, req,
                                         msrcdir, mtgtdir);
        }
@@ -2630,7 +2622,7 @@ relock:
 out_unlock_old:
        mdt_object_unlock(info, mold, lh_oldp, rc);
 out_put_new:
-       if (mnew != NULL)
+       if (mnew && !discard)
                mdt_object_put(info->mti_env, mnew);
 out_put_old:
        mdt_object_put(info->mti_env, mold);
@@ -2645,13 +2637,15 @@ out_put_tgtdir:
 out_put_srcdir:
        mdt_object_put(info->mti_env, msrcdir);
 
-       /* If 'discard' is set then new_fid must exits.
-        * DOM data discard need neither object nor lock,
-        * so do this at the end.
+       /* The DoM discard can be done right in the place above where it is
+        * assigned, meanwhile it is done here after rename unlock due to
+        * compatibility with old clients, for them the discard blocks
+        * the main thread until completion. Check LU-11359 for details.
         */
-       if (discard)
-               mdt_dom_discard_data(info, new_fid);
-
+       if (discard) {
+               mdt_dom_discard_data(info, mnew);
+               mdt_object_put(info->mti_env, mnew);
+       }
        return rc;
 }