Author: stefan2
Date: Thu Feb 19 21:33:58 2015
New Revision: 1661009
URL: http://svn.apache.org/r1661009
Log:
On the fsx-1.10 branch: Make DAG root nodes cachable.
* subversion/libsvn_fs_x/dag_cache.c
(get_root_node): New function to construct & cache root nodes.
(walk_dag_path): Call the new utility.
Modified:
subversion/branches/fsx-1.10/subversion/libsvn_fs_x/dag_cache.c
Modified: subversion/branches/fsx-1.10/subversion/libsvn_fs_x/dag_cache.c
URL:
http://svn.apache.org/viewvc/subversion/branches/fsx-1.10/subversion/libsvn_fs_x/dag_cache.c?rev=1661009&r1=1661008&r2=1661009&view=diff
==============================================================================
--- subversion/branches/fsx-1.10/subversion/libsvn_fs_x/dag_cache.c (original)
+++ subversion/branches/fsx-1.10/subversion/libsvn_fs_x/dag_cache.c Thu Feb 19
21:33:58 2015
@@ -625,6 +625,39 @@ dag_step(dag_node_t **child_p,
return SVN_NO_ERROR;
}
+/* Return the CHANGE_SET's root node in *NODE_P. ROOT is the FS API root
+ object for CHANGE_SET. Use SCRATCH_POOL for temporary allocations.
+
+ NOTE: *NODE_P will live within the DAG cache and we merely return a
+ reference to it. Hence, it will invalid upon the next cache insertion.
+ Callers must create a copy if they want a non-temporary object.
+ */
+static svn_error_t *
+get_root_node(dag_node_t **node_p,
+ svn_fs_root_t *root,
+ svn_fs_x__change_set_t change_set,
+ apr_pool_t *scratch_pool)
+{
+ svn_fs_t *fs = root->fs;
+ svn_fs_x__data_t *ffd = fs->fsap_data;
+ cache_entry_t *bucket;
+ const svn_string_t path = { "", 0 };
+
+ /* Auto-insert the node in the cache. */
+ auto_clear_dag_cache(ffd->dag_node_cache);
+ bucket = cache_lookup(ffd->dag_node_cache, change_set, &path);
+
+ /* If it is not already cached, construct the DAG node object for NODE_ID.
+ Let it live in the cache. Sadly, we often can't reuse txn DAG nodes. */
+ if (bucket->node == NULL)
+ SVN_ERR(svn_fs_x__root_node(&bucket->node, root,
+ ffd->dag_node_cache->pool, scratch_pool));
+
+ /* Return a reference to the cached object. */
+ *node_p = bucket->node;
+ return SVN_NO_ERROR;
+}
+
/* Walk the DAG starting at ROOT, following PATH and return a reference to
the target node in *NODE_P. Use SCRATCH_POOL for temporary allocations.
@@ -649,8 +682,8 @@ walk_dag_path(dag_node_t **node_p,
We will later assume that all paths have at least one parent level,
so we must check here for those that don't. */
if (path->len == 0)
- return svn_error_trace(svn_fs_x__root_node(node_p, root, scratch_pool,
- scratch_pool));
+ return svn_error_trace(get_root_node(node_p, root, change_set,
+ scratch_pool));
/* Callers often traverse the DAG in some path-based order or along the
history segments. That allows us to try a few guesses about where to
@@ -696,7 +729,7 @@ walk_dag_path(dag_node_t **node_p,
/* Make a parent_path item for the root node, using its own current
copy id. */
- SVN_ERR(svn_fs_x__root_node(&here, root, scratch_pool, iterpool));
+ SVN_ERR(get_root_node(&here, root, change_set, iterpool));
path->len = 0;
/* Walk the path segment by segment. */
