Function name and comment updates

Rename certain functions for more consistency when they share common
features. Make comments clearer about what arguments should be passed
to the insert and add functions.

Reviewed by: Sara Hartse <sara.hartse@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matt Ahrens <matt@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #9441

diff --git a/include/sys/btree.h b/include/sys/btree.h
index 1673b521750e015c8c48411090f09d434c48d9bb..9fe2534df1a4f806f31990174d30ba6af1558de4 100644 (file)
--- a/include/sys/btree.h
+++ b/include/sys/btree.h
@@ -131,10 +131,10 @@ void zfs_btree_create(zfs_btree_t *, int (*) (const void *, const void *),
 /*
  * Find a node with a matching value in the tree. Returns the matching node
  * found. If not found, it returns NULL and then if "where" is not NULL it sets
- * "where" for use with zfs_btree_insert() or zfs_btree_nearest().
+ * "where" for use with zfs_btree_add_idx() or zfs_btree_nearest().
  *
  * node   - node that has the value being looked for
- * where  - position for use with zfs_btree_nearest() or zfs_btree_insert(),
+ * where  - position for use with zfs_btree_nearest() or zfs_btree_add_idx(),
  *          may be NULL
  */
 void *zfs_btree_find(zfs_btree_t *, const void *, zfs_btree_index_t *);
@@ -145,17 +145,20 @@ void *zfs_btree_find(zfs_btree_t *, const void *, zfs_btree_index_t *);
  * node   - the node to insert
  * where  - position as returned from zfs_btree_find()
  */
-void zfs_btree_insert(zfs_btree_t *, const void *, const zfs_btree_index_t *);
+void zfs_btree_add_idx(zfs_btree_t *, const void *, const zfs_btree_index_t *);
 
 /*
- * Return the first or last valued node in the tree. Will return NULL
- * if the tree is empty.
+ * Return the first or last valued node in the tree. Will return NULL if the
+ * tree is empty. The index can be NULL if the location of the first or last
+ * element isn't required.
  */
 void *zfs_btree_first(zfs_btree_t *, zfs_btree_index_t *);
 void *zfs_btree_last(zfs_btree_t *, zfs_btree_index_t *);
 
 /*
- * Return the next or previous valued node in the tree.
+ * Return the next or previous valued node in the tree. The second index can
+ * safely be NULL, if the location of the next or previous value isn't
+ * required.
  */
 void *zfs_btree_next(zfs_btree_t *, const zfs_btree_index_t *,
     zfs_btree_index_t *);
@@ -169,7 +172,9 @@ void *zfs_btree_get(zfs_btree_t *, zfs_btree_index_t *);
 
 /*
  * Add a single value to the tree. The value must not compare equal to any
- * other node already in the tree.
+ * other node already in the tree. Note that the value will be copied out, not
+ * inserted directly. It is safe to free or destroy the value once this
+ * function returns.
  */
 void zfs_btree_add(zfs_btree_t *, const void *);
 
@@ -183,7 +188,7 @@ void zfs_btree_remove(zfs_btree_t *, const void *);
 /*
  * Remove the value at the given location from the tree.
  */
-void zfs_btree_remove_from(zfs_btree_t *, zfs_btree_index_t *);
+void zfs_btree_remove_idx(zfs_btree_t *, zfs_btree_index_t *);
 
 /*
  * Return the number of nodes in the tree

diff --git a/module/zfs/btree.c b/module/zfs/btree.c
index 8f514caabd9db4376c47ce3fd15d3f299f10f21b..f099eb67c7592a29a52aef7245d4d5176149a99a 100644 (file)
--- a/module/zfs/btree.c
+++ b/module/zfs/btree.c
@@ -980,7 +980,7 @@ zfs_btree_bulk_finish(zfs_btree_t *tree)
  * Insert value into tree at the location specified by where.
  */
 void
-zfs_btree_insert(zfs_btree_t *tree, const void *value,
+zfs_btree_add_idx(zfs_btree_t *tree, const void *value,
     const zfs_btree_index_t *where)
 {
        zfs_btree_index_t idx = {0};
@@ -1294,7 +1294,7 @@ zfs_btree_add(zfs_btree_t *tree, const void *node)
 {
        zfs_btree_index_t where = {0};
        VERIFY3P(zfs_btree_find(tree, node, &where), ==, NULL);
-       zfs_btree_insert(tree, node, &where);
+       zfs_btree_add_idx(tree, node, &where);
 }
 
 /* Helper function to free a tree node. */
@@ -1542,7 +1542,7 @@ zfs_btree_remove_from_node(zfs_btree_t *tree, zfs_btree_core_t *node,
 
 /* Remove the element at the specific location. */
 void
-zfs_btree_remove_from(zfs_btree_t *tree, zfs_btree_index_t *where)
+zfs_btree_remove_idx(zfs_btree_t *tree, zfs_btree_index_t *where)
 {
        size_t size = tree->bt_elem_size;
        zfs_btree_hdr_t *hdr = where->bti_node;
@@ -1778,7 +1778,7 @@ zfs_btree_remove(zfs_btree_t *tree, const void *value)
 {
        zfs_btree_index_t where = {0};
        VERIFY3P(zfs_btree_find(tree, value, &where), !=, NULL);
-       zfs_btree_remove_from(tree, &where);
+       zfs_btree_remove_idx(tree, &where);
 }
 
 /* Return the number of elements in the tree. */

diff --git a/module/zfs/dsl_scan.c b/module/zfs/dsl_scan.c
index 3eacb42f15ab84d884833b04db21664cff56bca7..b848f7ef3033c178e2bca3d9e7137eae075c4523 100644 (file)
--- a/module/zfs/dsl_scan.c
+++ b/module/zfs/dsl_scan.c
@@ -2925,13 +2925,23 @@ scan_io_queue_fetch_ext(dsl_scan_io_queue_t *queue)
                if (zfs_scan_issue_strategy == 1) {
                        return (range_tree_first(rt));
                } else if (zfs_scan_issue_strategy == 2) {
+                       /*
+                        * We need to get the original entry in the by_addr
+                        * tree so we can modify it.
+                        */
                        range_seg_t *size_rs =
                            zfs_btree_first(&queue->q_exts_by_size, NULL);
+                       if (size_rs == NULL)
+                               return (NULL);
                        uint64_t start = rs_get_start(size_rs, rt);
                        uint64_t size = rs_get_end(size_rs, rt) - start;
                        range_seg_t *addr_rs = range_tree_find(rt, start,
                            size);
                        ASSERT3P(addr_rs, !=, NULL);
+                       ASSERT3U(rs_get_start(size_rs, rt), ==,
+                           rs_get_start(addr_rs, rt));
+                       ASSERT3U(rs_get_end(size_rs, rt), ==,
+                           rs_get_end(addr_rs, rt));
                        return (addr_rs);
                }
        }
@@ -2948,12 +2958,21 @@ scan_io_queue_fetch_ext(dsl_scan_io_queue_t *queue)
        if (scn->scn_checkpointing) {
                return (range_tree_first(rt));
        } else if (scn->scn_clearing) {
+               /*
+                * We need to get the original entry in the by_addr
+                * tree so we can modify it.
+                */
                range_seg_t *size_rs = zfs_btree_first(&queue->q_exts_by_size,
                    NULL);
+               if (size_rs == NULL)
+                       return (NULL);
                uint64_t start = rs_get_start(size_rs, rt);
                uint64_t size = rs_get_end(size_rs, rt) - start;
                range_seg_t *addr_rs = range_tree_find(rt, start, size);
                ASSERT3P(addr_rs, !=, NULL);
+               ASSERT3U(rs_get_start(size_rs, rt), ==, rs_get_start(addr_rs,
+                   rt));
+               ASSERT3U(rs_get_end(size_rs, rt), ==, rs_get_end(addr_rs, rt));
                return (addr_rs);
        } else {
                return (NULL);

diff --git a/module/zfs/range_tree.c b/module/zfs/range_tree.c
index 0b369a43820fc4a8179e374e459155ca6065e3b0..1559605c21bab652aecc8720360359378380382a 100644 (file)
--- a/module/zfs/range_tree.c
+++ b/module/zfs/range_tree.c
@@ -349,7 +349,7 @@ range_tree_add_impl(void *arg, uint64_t start, uint64_t size, uint64_t fill)
                uint64_t before_start = rs_get_start_raw(rs_before, rt);
                uint64_t before_fill = rs_get_fill(rs_before, rt);
                uint64_t after_fill = rs_get_fill(rs_after, rt);
-               zfs_btree_remove_from(&rt->rt_root, &where_before);
+               zfs_btree_remove_idx(&rt->rt_root, &where_before);
 
                /*
                 * We have to re-find the node because our old reference is
@@ -385,7 +385,7 @@ range_tree_add_impl(void *arg, uint64_t start, uint64_t size, uint64_t fill)
                rs_set_start(rs, rt, start);
                rs_set_end(rs, rt, end);
                rs_set_fill(rs, rt, fill);
-               zfs_btree_insert(&rt->rt_root, rs, &where);
+               zfs_btree_add_idx(&rt->rt_root, rs, &where);
        }
 
        if (gap != 0) {
@@ -488,7 +488,7 @@ range_tree_remove_impl(range_tree_t *rt, uint64_t start, uint64_t size,
 
                rs_copy(rs, &rs_tmp, rt);
                if (zfs_btree_next(&rt->rt_root, &where, &where) != NULL)
-                       zfs_btree_insert(&rt->rt_root, &newseg, &where);
+                       zfs_btree_add_idx(&rt->rt_root, &newseg, &where);
                else
                        zfs_btree_add(&rt->rt_root, &newseg);
 
@@ -503,7 +503,7 @@ range_tree_remove_impl(range_tree_t *rt, uint64_t start, uint64_t size,
                rs_set_start(rs, rt, end);
                rs_copy(rs, &rs_tmp, rt);
        } else {
-               zfs_btree_remove_from(&rt->rt_root, &where);
+               zfs_btree_remove_idx(&rt->rt_root, &where);
                rs = NULL;
        }