Whamcloud - gitweb
LU-1299 clio: a combo patch to fix cl_lock
[fs/lustre-release.git] / lustre / lov / lov_lock.c
index 1c118f0..40192ce 100644 (file)
@@ -1,6 +1,4 @@
-/* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
- * vim:expandtab:shiftwidth=8:tabstop=8:
- *
+/*
  * GPL HEADER START
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
@@ -28,6 +26,8 @@
 /*
  * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
+ *
+ * Copyright (c) 2011, 2012, Whamcloud, Inc.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
@@ -267,12 +267,12 @@ static int lov_subresult(int result, int rc)
         int result_rank;
         int rc_rank;
 
+        ENTRY;
+
         LASSERT(result <= 0 || result == CLO_REPEAT || result == CLO_WAIT);
         LASSERT(rc <= 0 || rc == CLO_REPEAT || rc == CLO_WAIT);
         CLASSERT(CLO_WAIT < CLO_REPEAT);
 
-        ENTRY;
-
         /* calculate ranks in the ordering above */
         result_rank = result < 0 ? 1 + CLO_REPEAT : result;
         rc_rank = rc < 0 ? 1 + CLO_REPEAT : rc;
@@ -321,7 +321,7 @@ static int lov_lock_sub_init(const struct lu_env *env,
                         nr++;
         }
         LASSERT(nr > 0);
-        OBD_ALLOC(lck->lls_sub, nr * sizeof lck->lls_sub[0]);
+        OBD_ALLOC_LARGE(lck->lls_sub, nr * sizeof lck->lls_sub[0]);
         if (lck->lls_sub == NULL)
                 RETURN(-ENOMEM);
 
@@ -485,7 +485,8 @@ static void lov_lock_fini(const struct lu_env *env,
                          * a reference on its parent.
                          */
                         LASSERT(lck->lls_sub[i].sub_lock == NULL);
-                OBD_FREE(lck->lls_sub, lck->lls_nr * sizeof lck->lls_sub[0]);
+                OBD_FREE_LARGE(lck->lls_sub,
+                               lck->lls_nr * sizeof lck->lls_sub[0]);
         }
         OBD_SLAB_FREE_PTR(lck, lov_lock_kmem);
         EXIT;
@@ -523,7 +524,7 @@ static int lov_lock_enqueue_one(const struct lu_env *env, struct lov_lock *lck,
 
         /* first, try to enqueue a sub-lock ... */
         result = cl_enqueue_try(env, sublock, io, enqflags);
-        if (sublock->cll_state == CLS_ENQUEUED)
+        if ((sublock->cll_state == CLS_ENQUEUED) && !(enqflags & CEF_AGL))
                 /* if it is enqueued, try to `wait' on it---maybe it's already
                  * granted */
                 result = cl_wait_try(env, sublock);
@@ -532,8 +533,8 @@ static int lov_lock_enqueue_one(const struct lu_env *env, struct lov_lock *lck,
          * parallel, otherwise---enqueue has to wait until sub-lock is granted
          * before proceeding to the next one.
          */
-        if (result == CLO_WAIT && sublock->cll_state <= CLS_HELD &&
-            enqflags & CEF_ASYNC && !last)
+        if ((result == CLO_WAIT) && (sublock->cll_state <= CLS_HELD) &&
+            (enqflags & CEF_ASYNC) && (!last || (enqflags & CEF_AGL)))
                 result = 0;
         RETURN(result);
 }
@@ -696,7 +697,8 @@ static int lov_lock_unuse(const struct lu_env *env,
                 rc = lov_sublock_lock(env, lck, lls, closure, &subenv);
                 if (rc == 0) {
                         if (lls->sub_flags & LSF_HELD) {
-                                LASSERT(sublock->cll_state == CLS_HELD);
+                                LASSERT(sublock->cll_state == CLS_HELD ||
+                                        sublock->cll_state == CLS_ENQUEUED);
                                 rc = cl_unuse_try(subenv->lse_env, sublock);
                                 rc = lov_sublock_release(env, lck, i, 0, rc);
                         }
@@ -749,17 +751,9 @@ static void lov_lock_cancel(const struct lu_env *env,
 
                         switch(sublock->cll_state) {
                         case CLS_HELD:
-                                rc = cl_unuse_try(subenv->lse_env,
-                                                  sublock);
+                               rc = cl_unuse_try(subenv->lse_env, sublock);
                                 lov_sublock_release(env, lck, i, 0, 0);
                                 break;
-                        case CLS_ENQUEUED:
-                                /* TODO: it's not a good idea to cancel this
-                                 * lock because it's innocent. But it's
-                                 * acceptable. The better way would be to
-                                 * define a new lock method to unhold the
-                                 * dlm lock. */
-                                cl_lock_cancel(env, sublock);
                         default:
                                 lov_sublock_release(env, lck, i, 1, 0);
                                 break;
@@ -788,12 +782,15 @@ static int lov_lock_wait(const struct lu_env *env,
         struct lov_lock        *lck     = cl2lov_lock(slice);
         struct cl_lock_closure *closure = lov_closure_get(env, slice->cls_lock);
         enum cl_lock_state      minstate;
+        int                     reenqueued;
         int                     result;
         int                     i;
 
         ENTRY;
 
-        for (result = 0, minstate = CLS_FREEING, i = 0; i < lck->lls_nr; ++i) {
+again:
+        for (result = 0, minstate = CLS_FREEING, i = 0, reenqueued = 0;
+             i < lck->lls_nr; ++i) {
                 int rc;
                 struct lovsub_lock     *sub;
                 struct cl_lock         *sublock;
@@ -813,10 +810,18 @@ static int lov_lock_wait(const struct lu_env *env,
                         minstate = min(minstate, sublock->cll_state);
                         lov_sublock_unlock(env, sub, closure, subenv);
                 }
+                if (rc == CLO_REENQUEUED) {
+                        reenqueued++;
+                        rc = 0;
+                }
                 result = lov_subresult(result, rc);
                 if (result != 0)
                         break;
         }
+        /* Each sublock only can be reenqueued once, so will not loop for
+         * ever. */
+        if (result == 0 && reenqueued != 0)
+                goto again;
         cl_lock_closure_fini(closure);
         RETURN(result ?: minstate >= CLS_HELD ? 0 : CLO_WAIT);
 }
@@ -862,6 +867,11 @@ static int lov_lock_use(const struct lu_env *env,
                                 if (rc != 0)
                                         rc = lov_sublock_release(env, lck,
                                                                  i, 1, rc);
+                        } else if (sublock->cll_state == CLS_NEW) {
+                                /* Sub-lock might have been canceled, while
+                                 * top-lock was cached. */
+                                result = -ESTALE;
+                                lov_sublock_release(env, lck, i, 1, result);
                         }
                         lov_sublock_unlock(env, sub, closure, subenv);
                 }