LU-13415 dom: use DoM optimization for DOM+OST files

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

diff --git a/lustre/mdt/mdt_open.c b/lustre/mdt/mdt_open.c
index 5b36b78..6392580 100644 (file)
--- a/lustre/mdt/mdt_open.c
+++ b/lustre/mdt/mdt_open.c
@@ -809,8 +809,9 @@ static int mdt_object_open_lock(struct mdt_thread_info *info,
        bool try_layout = false;
        bool create_layout = false;
        int rc = 0;
-       int dom_stripes = LMM_NO_DOM;
-       bool dom_lock = false;
+       __u32 dom_stripe = 0;
+       unsigned int dom_only = 0;
+       unsigned int dom_lock = 0;
 
        ENTRY;
 
@@ -828,23 +829,23 @@ static int mdt_object_open_lock(struct mdt_thread_info *info,
                    ma->ma_need & MA_LOV)
                        try_layout = true;
 
-               /* DoM files can have just MDT stripe or combined MDT + OST
-                * stripes.
-                * - In the first case the open for read/write will do IO to
-                *   the MDT stripe and it makes sense to take IO lock in
-                *   advance along with OPEN even if it is blocking lock.
-                * - In the second case it is just size of MDT stripe and it
-                *   is quite unlikely that client will write into it, though
-                *   it may read it. So IO lock will be taken optionally if it
-                *   is non-blocking one.
+               /* DoM files can take IO lock at OPEN when it makes sense,
+                * check if file has DoM stripe and ask for lock if client
+                * no lock on that resource yet.
                 */
                if (ma->ma_valid & MA_LOV && ma->ma_lmm != NULL)
-                       dom_stripes = mdt_lmm_dom_entry(ma->ma_lmm);
-
-               if (dom_stripes == LMM_DOM_ONLY &&
-                   info->mti_mdt->mdt_opts.mo_dom_lock > 0 &&
+                       dom_stripe = mdt_lmm_dom_entry_check(ma->ma_lmm,
+                                                            &dom_only);
+               /* If only DOM stripe is being used then we can expect IO
+                * to it after OPEN and will return corresponding DOM ibit
+                * using default strategy from mdt_opts.mo_dom_lock.
+                * Otherwise trylock mode is used always and DOM ibit will
+                * be returned optionally.
+                */
+               if (dom_stripe &&
                    !mdt_dom_client_has_lock(info, mdt_object_fid(obj)))
-                       dom_lock = true;
+                       dom_lock = !dom_only ? TRYLOCK_DOM_ON_OPEN :
+                                  info->mti_mdt->mdt_opts.mo_dom_lock;
        }
 
        if (acq_lease) {
@@ -899,16 +900,14 @@ static int mdt_object_open_lock(struct mdt_thread_info *info,
                        lhc = &info->mti_lh[MDT_LH_LOCAL];
                } else if (dom_lock) {
                        lm = (open_flags & MDS_FMODE_WRITE) ? LCK_PW : LCK_PR;
-                       if (info->mti_mdt->mdt_opts.mo_dom_lock ==
-                           TRYLOCK_DOM_ON_OPEN) {
+                       if (dom_lock == TRYLOCK_DOM_ON_OPEN) {
                                trybits |= MDS_INODELOCK_DOM |
                                           MDS_INODELOCK_LAYOUT;
                        } else {
-                               /* mo_dom_lock == ALWAYS_DOM_LOCK_ON_OPEN */
+                               /* dom_lock == ALWAYS_DOM_LOCK_ON_OPEN */
                                *ibits = MDS_INODELOCK_DOM;
-                               if (info->mti_mdt->mdt_opts.mo_dom_read_open) {
+                               if (info->mti_mdt->mdt_opts.mo_dom_read_open)
                                        trybits |= MDS_INODELOCK_LAYOUT;
-                               }
                        }
                }