Re: [PATCH 02/16] radixtree: sync with mainline

[Wu Fengguang]

On Sun, Dec 04, 2005 at 03:57:50PM -0800, Andrew Morton wrote:
> Wu Fengguang <wfg@xxxxxxxxxxxxxxxx> wrote:
> >
> > [PATCH] radix-tree: Remove unnecessary indirections and clean up code
> > 
> >  is only partially merged into -mm tree. This patch completes it.
> 
> md: autorun ...               
> md: ... autorun DONE.
> Unable to handle kernel paging request at virtual address 8000003c

Sorry, the bug is caused by the returning line:

        return slot;

It should be

        return &slot;

The patch originally applies to
        
                        void *radix_tree_lookup()
        
But in -mm the function turns into
        
                        void **__lookup_slot()

And in my radixtree patch, it is

                        void *radix_tree_lookup_node()

The prototypes changed forth and back, so the problem was never discovered.

Wu
Subject: radixtree: sync with mainline
Cc: Christoph Lameter <clameter@xxxxxxx>

The patch from Christoph Lameter:

[PATCH] radix-tree: Remove unnecessary indirections and clean up code

is only partially merged into -mm tree. This patch completes it.

Signed-off-by: Christoph Lameter <clameter@xxxxxxx>
Signed-off-by: Wu Fengguang <wfg@xxxxxxxxxxxxxxxx>
 lib/radix-tree.c |   12 +++++-------
 1 files changed, 5 insertions(+), 7 deletions(-)

--- linux.orig/lib/radix-tree.c
+++ linux/lib/radix-tree.c
@@ -291,27 +291,25 @@ static inline void **__lookup_slot(struc
 				   unsigned long index)
 {
 	unsigned int height, shift;
-	struct radix_tree_node **slot;
+	struct radix_tree_node *slot;
 
 	height = root->height;
 	if (index > radix_tree_maxindex(height))
 		return NULL;
 
 	shift = (height-1) * RADIX_TREE_MAP_SHIFT;
-	slot = &root->rnode;
+	slot = root->rnode;
 
 	while (height > 0) {
-		if (*slot == NULL)
+		if (slot == NULL)
 			return NULL;
 
-		slot = (struct radix_tree_node **)
-			((*slot)->slots +
-				((index >> shift) & RADIX_TREE_MAP_MASK));
+		slot = slot->slots[(index >> shift) & RADIX_TREE_MAP_MASK];
 		shift -= RADIX_TREE_MAP_SHIFT;
 		height--;
 	}
 
-	return (void **)slot;
+	return &slot;
 }
 
 /**