From: Stephen Warren <[email protected]>
The following pattern of code is tempting:
for_each_matching_node(np, table) {
match = of_match_node(table, np);
However, this results in iterating over table twice; the second time
inside of_match_node(). The implementation of for_each_matching_node()
already found the match, so this is redundant. Invent new function
of_find_matching_node_and_match() and macro
for_each_matching_node_and_match() to remove the double iteration,
thus transforming the above code to:
for_each_matching_node_and_match(np, table, &match)
Signed-off-by: Stephen Warren <[email protected]>
---
v4: New patch.
This series is based on the ARM sys_timer rework that I posted yesterday,
although patch 1/3 should be completely independant of that, and could
perhaps even be applied for 3.8 right now.
I hope that these patches can be taken through arm-soc tree for 3.9;
I will repost them based on 3.8-rc1 at the appropriate time.
---
drivers/of/base.c | 18 +++++++++++++-----
include/linux/of.h | 15 +++++++++++++--
2 files changed, 26 insertions(+), 7 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index f2f63c8..094271e 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -594,27 +594,35 @@ const struct of_device_id *of_match_node(const struct
of_device_id *matches,
EXPORT_SYMBOL(of_match_node);
/**
- * of_find_matching_node - Find a node based on an of_device_id match
- * table.
+ * of_find_matching_node_and_match - Find a node based on an of_device_id
+ * match table.
* @from: The node to start searching from or NULL, the node
* you pass will not be searched, only the next one
* will; typically, you pass what the previous call
* returned. of_node_put() will be called on it
* @matches: array of of device match structures to search in
+ * @match Updated to point at the matches entry which matched
*
* Returns a node pointer with refcount incremented, use
* of_node_put() on it when done.
*/
-struct device_node *of_find_matching_node(struct device_node *from,
- const struct of_device_id *matches)
+struct device_node *of_find_matching_node_and_match(struct device_node *from,
+ const struct of_device_id *matches,
+ const struct of_device_id **match)
{
struct device_node *np;
+ if (match)
+ *match = NULL;
+
read_lock(&devtree_lock);
np = from ? from->allnext : allnodes;
for (; np; np = np->allnext) {
- if (of_match_node(matches, np) && of_node_get(np))
+ if (of_match_node(matches, np) && of_node_get(np)) {
+ if (match)
+ *match = matches;
break;
+ }
}
of_node_put(from);
read_unlock(&devtree_lock);
diff --git a/include/linux/of.h b/include/linux/of.h
index 681a6c8..1000496 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -180,11 +180,22 @@ extern struct device_node *of_find_compatible_node(struct
device_node *from,
#define for_each_compatible_node(dn, type, compatible) \
for (dn = of_find_compatible_node(NULL, type, compatible); dn; \
dn = of_find_compatible_node(dn, type, compatible))
-extern struct device_node *of_find_matching_node(struct device_node *from,
- const struct of_device_id *matches);
+extern struct device_node *of_find_matching_node_and_match(
+ struct device_node *from,
+ const struct of_device_id *matches,
+ const struct of_device_id **match);
+static inline struct device_node *of_find_matching_node(
+ struct device_node *from,
+ const struct of_device_id *matches)
+{
+ return of_find_matching_node_and_match(from, matches, NULL);
+}
#define for_each_matching_node(dn, matches) \
for (dn = of_find_matching_node(NULL, matches); dn; \
dn = of_find_matching_node(dn, matches))
+#define for_each_matching_node_and_match(dn, matches, match) \
+ for (dn = of_find_matching_node_and_match(NULL, matches, match); \
+ dn; dn = of_find_matching_node_and_match(dn, matches, match))
extern struct device_node *of_find_node_by_path(const char *path);
extern struct device_node *of_find_node_by_phandle(phandle handle);
extern struct device_node *of_get_parent(const struct device_node *node);
--
1.7.10.4
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