Normalize against incoming page buffering changes.

1 files changed, 534 insertions, 17 deletions

diff --git a/src/H5C.c b/src/H5C.c
index fe97f05..804eaf5 100644
--- a/src/H5C.c
+++ b/src/H5C.c
@@ -159,6 +159,10 @@ static herr_t H5C__mark_flush_dep_dirty(H5C_cache_entry_t * entry);
 
 static herr_t H5C__mark_flush_dep_clean(H5C_cache_entry_t * entry);
 
+static herr_t H5C__serialize_ring(H5F_t *f, hid_t dxpl_id, H5C_ring_t ring);
+static herr_t H5C__serialize_single_entry(H5F_t *f, hid_t dxpl_id, 
+    H5C_t *cache_ptr, H5C_cache_entry_t *entry_ptr);
+
 static herr_t H5C__verify_len_eoa(H5F_t *f, const H5C_class_t * type,
     haddr_t addr, size_t *len, hbool_t actual);
 
@@ -750,20 +754,10 @@ H5C_prep_for_file_close(H5F_t *f, hid_t dxpl_id)
     /* Make certain there aren't any protected entries */
     HDassert(cache_ptr->pl_len == 0);
 
-    /* If the file is opened and closed without any access to 
-     * any group or dataset, it is possible that the cache image (if 
-     * it exists) has not been read yet.  Do this now if required.
-     */
-    if(cache_ptr->load_image) {
-        cache_ptr->load_image = FALSE;
-        if(H5C__load_cache_image(f, dxpl_id) < 0)
-	    HGOTO_ERROR(H5E_CACHE, H5E_CANTLOAD, FAIL, "Can't load cache image")
-    } /* end if */
+    /* Prepare cache image */
+    if(H5C__prep_image_for_file_close(f, dxpl_id) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTCREATE, FAIL, "can't create cache image")
 
-    /* Generate the cache image, if requested */
-    if(cache_ptr->image_ctl.generate_image)
-        if(H5C__prep_image_for_file_close(f, dxpl_id) < 0)
-	    HGOTO_ERROR(H5E_CACHE, H5E_CANTCREATE, FAIL, "Can't create cache image")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -5310,7 +5304,7 @@ H5C_flush_invalidate_ring(H5F_t * f, hid_t dxpl_id, H5C_ring_t ring,
     H5C_cache_entry_t  *entry_ptr = NULL;
     H5C_cache_entry_t  *next_entry_ptr = NULL;
 #if H5C_DO_SANITY_CHECKS
-    int64_t             initial_slist_len = 0;
+    uint32_t            initial_slist_len = 0;
     size_t              initial_slist_size = 0;
 #endif /* H5C_DO_SANITY_CHECKS */
     herr_t              ret_value = SUCCEED;
@@ -5545,7 +5539,7 @@ H5C_flush_invalidate_ring(H5F_t * f, hid_t dxpl_id, H5C_ring_t ring,
 
         if(node_ptr == NULL) {
             HDassert(cache_ptr->slist_len == (initial_slist_len + cache_ptr->slist_len_increase));
-            HDassert((int64_t)cache_ptr->slist_size == ((int64_t)initial_slist_size + cache_ptr->slist_size_increase));
+            HDassert(cache_ptr->slist_size == (initial_slist_size + cache_ptr->slist_size_increase));
         } /* end if */
 #endif /* H5C_DO_SANITY_CHECKS */
 
@@ -5747,7 +5741,7 @@ H5C_flush_ring(H5F_t *f, hid_t dxpl_id, H5C_ring_t ring,  unsigned flags)
     H5C_cache_entry_t *	entry_ptr = NULL;
     H5C_cache_entry_t *	next_entry_ptr = NULL;
 #if H5C_DO_SANITY_CHECKS
-    int64_t		initial_slist_len = 0;
+    uint32_t		initial_slist_len = 0;
     size_t              initial_slist_size = 0;
 #endif /* H5C_DO_SANITY_CHECKS */
     int                 i;
@@ -5953,7 +5947,7 @@ H5C_flush_ring(H5F_t *f, hid_t dxpl_id, H5C_ring_t ring,  unsigned flags)
 #if H5C_DO_SANITY_CHECKS
         /* Verify that the slist size and length are as expected. */
         HDassert((initial_slist_len + cache_ptr->slist_len_increase) == cache_ptr->slist_len);
-        HDassert((size_t)((int64_t)initial_slist_size + cache_ptr->slist_size_increase) == cache_ptr->slist_size);
+        HDassert((initial_slist_size + cache_ptr->slist_size_increase) == cache_ptr->slist_size);
 #endif /* H5C_DO_SANITY_CHECKS */
     } /* while */
 
@@ -7996,6 +7990,529 @@ H5C__assert_flush_dep_nocycle(const H5C_cache_entry_t * entry,
 
 
 /*-------------------------------------------------------------------------
+ * Function:    H5C__serialize_cache
+ *
+ * Purpose:	Serialize (i.e. construct an on disk image) for all entries 
+ *		in the metadata cache including clean entries.  
+ *
+ *		Note that flush dependencies and "flush me last" flags
+ *		must be observed in the serialization process.  
+ *
+ *		Note also that entries may be loaded, flushed, evicted,
+ *		expunged, relocated, resized, or removed from the cache
+ *		during this process, just as these actions may occur during
+ *		a regular flush.
+ *
+ *		However, we are given that the cache will contain no protected
+ *		entries on entry to this routine (although entries may be 
+ *		briefly protected and then unprotected during the serialize 
+ *		process).  
+ *
+ *		The objective of this routine is serialize all entries and 
+ *		to force all entries into their actual locations on disk.  
+ *
+ *		The initial need for this routine is to settle all entries 
+ *		in the cache prior to construction of the metadata cache 
+ *		image so that the size of the cache image can be calculated.
+ *		However, I gather that other uses for the routine are 
+ *		under consideration.
+ *
+ * Return:      Non-negative on success/Negative on failure or if there was
+ *		a request to flush all items and something was protected.
+ *
+ * Programmer:  John Mainzer
+ *		7/22/15
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5C__serialize_cache(H5F_t *f, hid_t dxpl_id)
+{
+#if H5C_DO_SANITY_CHECKS
+    int                 i;
+    uint32_t            index_len = 0;
+    size_t              index_size = (size_t)0;
+    size_t              clean_index_size = (size_t)0;
+    size_t              dirty_index_size = (size_t)0;
+    size_t              slist_size = (size_t)0;
+    uint32_t            slist_len = 0;
+#endif /* H5C_DO_SANITY_CHECKS */
+    H5C_ring_t          ring;
+    H5C_t             * cache_ptr;
+    herr_t              ret_value = SUCCEED;
+
+    FUNC_ENTER_PACKAGE
+
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(f->shared);
+    cache_ptr = f->shared->cache;
+    HDassert(cache_ptr);
+    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
+    HDassert(cache_ptr->slist_ptr);
+
+#if H5C_DO_SANITY_CHECKS
+    HDassert(cache_ptr->index_ring_len[H5C_RING_UNDEFINED] == 0);
+    HDassert(cache_ptr->index_ring_size[H5C_RING_UNDEFINED] == (size_t)0);
+    HDassert(cache_ptr->clean_index_ring_size[H5C_RING_UNDEFINED] == (size_t)0);
+    HDassert(cache_ptr->dirty_index_ring_size[H5C_RING_UNDEFINED] == (size_t)0);
+    HDassert(cache_ptr->slist_ring_len[H5C_RING_UNDEFINED] == 0);
+    HDassert(cache_ptr->slist_ring_size[H5C_RING_UNDEFINED] == (size_t)0);
+
+    for(i = H5C_RING_USER; i < H5C_RING_NTYPES; i++) {
+        index_len += cache_ptr->index_ring_len[i];
+        index_size += cache_ptr->index_ring_size[i];
+        clean_index_size += cache_ptr->clean_index_ring_size[i];
+        dirty_index_size += cache_ptr->dirty_index_ring_size[i];
+
+        slist_len += cache_ptr->slist_ring_len[i];
+        slist_size += cache_ptr->slist_ring_size[i];
+    } /* end for */
+
+    HDassert(cache_ptr->index_len == index_len);
+    HDassert(cache_ptr->index_size == index_size);
+    HDassert(cache_ptr->clean_index_size == clean_index_size);
+    HDassert(cache_ptr->dirty_index_size == dirty_index_size);
+    HDassert(cache_ptr->slist_len == slist_len);
+    HDassert(cache_ptr->slist_size == slist_size);
+#endif /* H5C_DO_SANITY_CHECKS */
+
+#if H5C_DO_EXTREME_SANITY_CHECKS
+    if((H5C_validate_protected_entry_list(cache_ptr) < 0) ||
+            (H5C_validate_pinned_entry_list(cache_ptr) < 0) ||
+            (H5C_validate_lru_list(cache_ptr) < 0))
+        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "an extreme sanity check failed on entry")
+#endif /* H5C_DO_EXTREME_SANITY_CHECKS */
+
+#ifndef NDEBUG
+    /* if this is a debug build, set the serialization_count field of 
+     * each entry in the cache to zero before we start the serialization.
+     * This allows us to detect the case in which any entry is serialized
+     * more than once (a performance issues), and more importantly, the 
+     * case is which any flush depencency parent is serializes more than
+     * once (a correctness issue).
+     */
+     {
+        H5C_cache_entry_t * scan_ptr = NULL;
+
+        scan_ptr = cache_ptr->il_head;
+        while(scan_ptr != NULL) {
+	    HDassert(scan_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+	    scan_ptr->serialization_count = 0;
+	    scan_ptr = scan_ptr->il_next;
+        } /* end while */
+     } /* end block */
+#endif /* NDEBUG */
+
+    /* set cache_ptr->serialization_in_progress to TRUE, and back 
+     * to FALSE at the end of the function.  Must maintain this flag
+     * to support H5C_get_serialization_in_progress(), which is in 
+     * turn required to support sanity checking in some cache 
+     * clients.
+     */
+    HDassert(!cache_ptr->serialization_in_progress);
+    cache_ptr->serialization_in_progress = TRUE;
+
+    /* Serialize each ring, starting from the outermost ring and
+     * working inward.
+     */
+    ring = H5C_RING_USER;
+    while(ring < H5C_RING_NTYPES) {
+	HDassert(cache_ptr->close_warning_received);
+        switch(ring) {
+            case H5C_RING_USER:
+                break;
+
+            case H5C_RING_RDFSM:
+                if(!cache_ptr->rdfsm_settled) {
+                    hbool_t fsm_settled = FALSE;        /* Whether the FSM was actually settled */
+
+                    /* Settle raw data FSM */
+                    if(H5MF_settle_raw_data_fsm(f, dxpl_id, &fsm_settled) < 0)
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "RD FSM settle failed")
+
+                    /* Only set the flag if the FSM was actually settled */
+                    if(fsm_settled)
+                        cache_ptr->rdfsm_settled = TRUE;
+                } /* end if */
+                break;
+
+            case H5C_RING_MDFSM:
+                if(!cache_ptr->mdfsm_settled) {
+                    hbool_t fsm_settled = FALSE;        /* Whether the FSM was actually settled */
+
+                    /* Settle metadata FSM */
+                    if(H5MF_settle_meta_data_fsm(f, dxpl_id, &fsm_settled) < 0)
+                        HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "MD FSM settle failed")
+
+                    /* Only set the flag if the FSM was actually settled */
+                    if(fsm_settled)
+                        cache_ptr->mdfsm_settled = TRUE;
+                } /* end if */
+                break;
+
+            case H5C_RING_SBE:
+            case H5C_RING_SB:
+                break;
+
+            default:
+                HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "Unknown ring?!?!")
+                break;
+        } /* end switch */
+
+        if(H5C__serialize_ring(f, dxpl_id, ring) < 0)
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "serialize ring failed")
+
+        ring++;
+    } /* end while */
+
+#ifndef NDEBUG
+    /* Verify that no entry has been serialized more than once.
+     * FD parents with multiple serializations should have been caught
+     * elsewhere, so no specific check for them here.
+     */
+     {
+        H5C_cache_entry_t * scan_ptr = NULL;
+
+        scan_ptr = cache_ptr->il_head;
+        while(scan_ptr != NULL) {
+	    HDassert(scan_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+	    HDassert(scan_ptr->serialization_count <= 1);
+
+	    scan_ptr = scan_ptr->il_next;
+        } /* end while */
+     } /* end block */
+#endif /* NDEBUG */
+
+done:
+    cache_ptr->serialization_in_progress = FALSE;
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5C__serialize_cache() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5C__serialize_ring
+ *
+ * Purpose:     Serialize the entries contained in the specified cache and
+ *              ring.  All entries in rings outside the specified ring
+ *              must have been serialized on entry.
+ *
+ *              If the cache contains protected entries in the specified
+ *              ring, the function will fail, as protected entries cannot
+ *              be serialized.  However all unprotected entries in the 
+ *		target ring should be serialized before the function 
+ *		returns failure.
+ *
+ *              If flush dependencies appear in the target ring, the
+ *              function makes repeated passes through the index list
+ *		serializing entries in flush dependency order.
+ *
+ *		All entries outside the H5C_RING_SBE are marked for 
+ *		inclusion in the cache image.  Entries in H5C_RING_SBE 
+ *		and below are marked for exclusion from the image.
+ *
+ * Return:      Non-negative on success/Negative on failure or if there was
+ *              a request to flush all items and something was protected.
+ *
+ * Programmer:  John Mainzer
+ *              9/11/15
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5C__serialize_ring(H5F_t *f, hid_t dxpl_id, H5C_ring_t ring)
+{
+    hbool_t		done = FALSE;
+    H5C_t             * cache_ptr;
+    H5C_cache_entry_t * entry_ptr;
+    herr_t              ret_value = SUCCEED;
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(f->shared);
+    cache_ptr = f->shared->cache;
+    HDassert(cache_ptr);
+    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
+    HDassert(ring > H5C_RING_UNDEFINED);
+    HDassert(ring < H5C_RING_NTYPES);
+
+    HDassert(cache_ptr->serialization_in_progress);
+
+    /* The objective here is to serialize all entries in the cache ring
+     * in flush dependency order.
+     *
+     * The basic algorithm is to scan the cache index list looking for 
+     * unserialized entries that are either not in a flush dependency
+     * relationship, or which have no unserialized children.  Any such
+     * entry is serialized and its flush dependency parents (if any) are 
+     * informed -- allowing them to decrement their userialized child counts.
+     *
+     * However, this algorithm is complicated by the ability
+     * of client serialization callbacks to perform operations on 
+     * on the cache which can result in the insertion, deletion, 
+     * relocation, resize, dirty, flush, eviction, or removal (via the
+     * take ownership flag) of entries.  Changes in the flush dependency
+     * structure are also possible.
+     *
+     * On the other hand, the algorithm is simplified by the fact that 
+     * we are serializing, not flushing.  Thus, as long as all entries 
+     * are serialized correctly, it doesn't matter if we have to go back
+     * and serialize an entry a second time.
+     *
+     * These possible actions result in the following modfications to 
+     * tha basic algorithm:
+     *
+     * 1) In the event of an entry expunge, eviction or removal, we must 
+     *    restart the scan as it is possible that the next entry in our 
+     *    scan is no longer in the cache.  Were we to examine this entry,
+     *    we would be accessing deallocated memory.
+     *
+     * 2) A resize, dirty, or insertion of an entry may result in the 
+     *    the increment of a flush dependency parent's dirty and/or 
+     *    unserialized child count.  In the context of serializing the 
+     *    the cache, this is a non-issue, as even if we have already 
+     *    serialized the parent, it will be marked dirty and its image 
+     *    marked out of date if appropriate when the child is serialized.  
+     *    
+     *    However, this is a major issue for a flush, as were this to happen
+     *    in a flush, it would violate the invariant that the flush dependency
+     *    feature is intended to enforce.  As the metadata cache has no 
+     *    control over the behavior of cache clients, it has no way of 
+     *    preventing this behaviour.  However, it should detect it if at all
+     *    possible.  
+     *
+     *    Do this by maintaining a count of the number of times each entry is
+     *    serialized during a cache serialization.  If any flush dependency 
+     *    parent is serialized more than once, throw an assertion failure.
+     *
+     * 3) An entry relocation will typically change the location of the 
+     *    entry in the index list.  This shouldn't cause problems as we 
+     *    will scan the index list until we make a complete pass without 
+     *    finding anything to serialize -- making relocations of either 
+     *    the current or next entries irrelevant.
+     *
+     *    Note that since a relocation may result in our skipping part of 
+     *    the index list, we must always do at least one more pass through
+     *    the index list after an entry relocation.
+     *
+     * 4) Changes in the flush dependency structure are possible on 
+     *    entry insertion, load, expunge, evict, or remove.  Destruction
+     *    of a flush dependency has no effect, as it can only relax the 
+     *    flush dependencies.  Creation of a flush dependency can create
+     *    an unserialized child of a flush dependency parent where all 
+     *    flush dependency children were previously serialized.  Should
+     *    this child dirty the flush dependency parent when it is serialized,
+     *    the parent will be re-serialized.
+     *
+     *    Per the discussion of 2) above, this is a non issue for cache 
+     *    serialization, and a major problem for cache flush.  Using the
+     *    same detection mechanism, throw an assertion failure if this 
+     *    condition appears.  
+     *
+     * Observe that either eviction or removal of entries as a result of 
+     * a serialization is not a problem as long as the flush depencency 
+     * tree does not change beyond the removal of a leaf.
+     */
+    while(!done) {
+        /* Reset the counters so that we can detect insertions, loads,
+         * moves, and flush dependency height changes caused by the pre_serialize
+         * and serialize callbacks.
+         */
+        cache_ptr->entries_loaded_counter         = 0;
+        cache_ptr->entries_inserted_counter	  = 0;
+        cache_ptr->entries_relocated_counter      = 0;
+
+	done = TRUE; /* set to FALSE if any activity in inner loop */
+	entry_ptr = cache_ptr->il_head;
+	while(entry_ptr != NULL) {
+	    HDassert(entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+
+	    /* Verify that either the entry is already serialized, or
+             * that it is assigned to either the target or an inner 
+             * ring.
+             */
+            HDassert((entry_ptr->ring >= ring) || (entry_ptr->image_up_to_date));
+
+	    /* Skip flush me last entries or inner ring entries */
+	    if(!entry_ptr->flush_me_last && entry_ptr->ring == ring) {
+
+		/* if we encounter an unserialized entry in the current
+                 * ring that is not marked flush me last, we are not done.
+                 */
+		if(!entry_ptr->image_up_to_date)
+		    done = FALSE;
+
+		/* Serialize the entry if its image is not up to date
+                 * and it has no unserialized flush dependency children.
+                 */
+		if(!entry_ptr->image_up_to_date && entry_ptr->flush_dep_nunser_children == 0) {
+		    HDassert(entry_ptr->serialization_count == 0);
+
+		    /* Serialize the entry */
+		    if(H5C__serialize_single_entry(f, dxpl_id, cache_ptr, entry_ptr) < 0)
+            	        HGOTO_ERROR(H5E_CACHE, H5E_CANTSERIALIZE, FAIL, "entry serialization failed")
+
+                    HDassert(entry_ptr->flush_dep_nunser_children == 0);
+		    HDassert(entry_ptr->serialization_count == 0);
+
+#ifndef NDEBUG
+                    /* Increment serialization counter (to detect multiple serializations) */
+		    entry_ptr->serialization_count++;
+#endif /* NDEBUG */
+                 } /* end if */
+            } /* end if */
+
+            /* Check for the cache being perturbed during the entry serialize */
+            if((cache_ptr->entries_loaded_counter > 0) ||
+                    (cache_ptr->entries_inserted_counter > 0) ||
+                    (cache_ptr->entries_relocated_counter > 0)) {
+
+#if H5C_COLLECT_CACHE_STATS
+                H5C__UPDATE_STATS_FOR_INDEX_SCAN_RESTART(cache_ptr);
+#endif /* H5C_COLLECT_CACHE_STATS */
+
+                /* Reset the counters */
+                cache_ptr->entries_loaded_counter         = 0;
+                cache_ptr->entries_inserted_counter	  = 0;
+                cache_ptr->entries_relocated_counter      = 0;
+
+                /* Restart scan */
+                entry_ptr = cache_ptr->il_head;
+            } /* end if */
+            else
+                /* Advance to next entry */
+	        entry_ptr = entry_ptr->il_next;
+	} /* while ( entry_ptr != NULL ) */
+    } /* while ( ! done ) */
+
+
+    /* Reset the counters so that we can detect insertions, loads,
+     * moves, and flush dependency height changes caused by the pre_serialize
+     * and serialize callbacks.
+     */
+    cache_ptr->entries_loaded_counter     = 0;
+    cache_ptr->entries_inserted_counter	  = 0;
+    cache_ptr->entries_relocated_counter  = 0;
+
+    /* At this point, all entries not marked "flush me last" and in
+     * the current ring or outside it should be serialized and have up 
+     * to date images.  Scan the index list again to serialize the 
+     * "flush me last" entries (if they are in the current ring) and to 
+     * verify that all other entries have up to date images.
+     */
+    entry_ptr = cache_ptr->il_head;
+    while(entry_ptr != NULL) {
+	HDassert(entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    	HDassert(entry_ptr->ring > H5C_RING_UNDEFINED);
+        HDassert(entry_ptr->ring < H5C_RING_NTYPES);
+        HDassert((entry_ptr->ring >= ring) || (entry_ptr->image_up_to_date));
+
+	if(entry_ptr->ring == ring) {
+	    if(entry_ptr->flush_me_last) {
+		if(!entry_ptr->image_up_to_date) {
+		    HDassert(entry_ptr->serialization_count == 0);
+                    HDassert(entry_ptr->flush_dep_nunser_children == 0);
+
+	            /* Serialize the entry */
+	            if(H5C__serialize_single_entry(f, dxpl_id,  cache_ptr, entry_ptr) < 0)
+		        HGOTO_ERROR(H5E_CACHE, H5E_CANTSERIALIZE, FAIL, "entry serialization failed")
+
+                    /* Check for the cache changing */
+                    if((cache_ptr->entries_loaded_counter > 0) ||
+                            (cache_ptr->entries_inserted_counter > 0) ||
+                            (cache_ptr->entries_relocated_counter > 0))
+		        HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "flush_me_last entry serialization triggered restart")
+
+                    HDassert(entry_ptr->flush_dep_nunser_children == 0);
+		    HDassert(entry_ptr->serialization_count == 0);
+#ifndef NDEBUG
+                    /* Increment serialization counter (to detect multiple serializations) */
+		    entry_ptr->serialization_count++;
+#endif /* NDEBUG */
+                } /* end if */
+            } /* end if */
+            else {
+	        HDassert(entry_ptr->image_up_to_date);
+		HDassert(entry_ptr->serialization_count <= 1);
+                HDassert(entry_ptr->flush_dep_nunser_children == 0);
+            }  /* end else */
+        } /* if ( entry_ptr->ring == ring ) */
+
+	entry_ptr = entry_ptr->il_next;
+    } /* while ( entry_ptr != NULL ) */
+
+done:
+    HDassert(cache_ptr->serialization_in_progress);
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5C__serialize_ring() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5C__serialize_single_entry
+ *
+ * Purpose:     Serialize the cache entry pointed to by the entry_ptr 
+ *		parameter.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  John Mainzer, 7/24/15
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5C__serialize_single_entry(H5F_t *f, hid_t dxpl_id, H5C_t *cache_ptr,
+    H5C_cache_entry_t *entry_ptr)
+{
+    herr_t		ret_value = SUCCEED;      /* Return value */
+
+    FUNC_ENTER_STATIC
+
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(cache_ptr);
+    HDassert(cache_ptr->magic == H5C__H5C_T_MAGIC);
+    HDassert(entry_ptr);
+    HDassert(entry_ptr->magic == H5C__H5C_CACHE_ENTRY_T_MAGIC);
+    HDassert(!entry_ptr->prefetched);
+    HDassert(!entry_ptr->image_up_to_date);
+    HDassert(entry_ptr->is_dirty);
+    HDassert(!entry_ptr->is_protected);
+    HDassert(!entry_ptr->flush_in_progress);
+    HDassert(entry_ptr->type);
+
+    /* Set entry_ptr->flush_in_progress to TRUE so the the target entry
+     * will not be evicted out from under us.  Must set it back to FALSE
+     * when we are done.
+     */
+    entry_ptr->flush_in_progress = TRUE;
+
+    /* Allocate buffer for the entry image if required. */
+    if(NULL == entry_ptr->image_ptr) {
+        HDassert(entry_ptr->size > 0);
+        if(NULL == (entry_ptr->image_ptr = H5MM_malloc(entry_ptr->size + H5C_IMAGE_EXTRA_SPACE)) )
+            HGOTO_ERROR(H5E_CACHE, H5E_CANTALLOC, FAIL, "memory allocation failed for on disk image buffer")
+#if H5C_DO_MEMORY_SANITY_CHECKS
+        HDmemcpy(((uint8_t *)entry_ptr->image_ptr) + image_size, H5C_IMAGE_SANITY_VALUE, H5C_IMAGE_EXTRA_SPACE);
+#endif /* H5C_DO_MEMORY_SANITY_CHECKS */
+    } /* end if */
+
+    /* Generate image for entry */
+    if(H5C__generate_image(f, cache_ptr, entry_ptr, dxpl_id) < 0)
+        HGOTO_ERROR(H5E_CACHE, H5E_CANTSERIALIZE, FAIL, "Can't generate image for cache entry")
+
+    /* Reset the flush_in progress flag */
+    entry_ptr->flush_in_progress = FALSE;
+
+done:
+    HDassert((ret_value != SUCCEED) || (!entry_ptr->flush_in_progress));
+    HDassert((ret_value != SUCCEED) || (entry_ptr->image_up_to_date));
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5C__serialize_single_entry() */
+
+
+/*-------------------------------------------------------------------------
  * Function:    H5C__generate_image
  *
  * Purpose:     Serialize an entry and generate its image.