Commit b3f9da79 authored by Kent Overstreet's avatar Kent Overstreet
Browse files

lib/generic-radix-tree.c: add preallocation 



Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent f6594633

include/linux/generic-radix-tree.h

+32 −6
Original line number Diff line number Diff line
@@ -41,6 +41,7 @@ 
#include <linux/limits.h>

#include <linux/log2.h>

#include <linux/math.h>

#include <linux/slab.h>

#include <linux/types.h>



struct genradix_root;
@@ -81,6 +82,10 @@ static inline struct genradix_node *genradix_root_to_node(struct genradix_root * 
	return (void *) ((unsigned long) r & ~GENRADIX_DEPTH_MASK);

}



struct __genradix {

	struct genradix_root		*root;

};



struct genradix_node {

	union {

		/* Interior node: */
@@ -91,9 +96,15 @@ struct genradix_node { 
	};

};



struct __genradix {

	struct genradix_root		*root;

};

static inline struct genradix_node *genradix_alloc_node(gfp_t gfp_mask)

{

	return kzalloc(GENRADIX_NODE_SIZE, gfp_mask);

}



static inline void genradix_free_node(struct genradix_node *node)

{

	kfree(node);

}



/*

 * NOTE: currently, sizeof(_type) must not be larger than GENRADIX_NODE_SIZE:
@@ -209,7 +220,8 @@ void *__genradix_ptr(struct __genradix *, size_t); 
	 __genradix_ptr(&(_radix)->tree,			\

			__genradix_idx_to_offset(_radix, _idx)))



void *__genradix_ptr_alloc(struct __genradix *, size_t, gfp_t);

void *__genradix_ptr_alloc(struct __genradix *, size_t,

			   struct genradix_node **, gfp_t);



#define genradix_ptr_alloc_inlined(_radix, _idx, _gfp)			\

	(__genradix_cast(_radix)					\
@@ -217,7 +229,15 @@ void *__genradix_ptr_alloc(struct __genradix *, size_t, gfp_t); 
			__genradix_idx_to_offset(_radix, _idx)) ?:	\

	  __genradix_ptr_alloc(&(_radix)->tree,				\

			__genradix_idx_to_offset(_radix, _idx),		\

			_gfp)))

			NULL, _gfp)))



#define genradix_ptr_alloc_preallocated_inlined(_radix, _idx, _new_node, _gfp)\

	(__genradix_cast(_radix)					\

	 (__genradix_ptr_inlined(&(_radix)->tree,			\

			__genradix_idx_to_offset(_radix, _idx)) ?:	\

	  __genradix_ptr_alloc(&(_radix)->tree,				\

			__genradix_idx_to_offset(_radix, _idx),		\

			_new_node, _gfp)))



/**

 * genradix_ptr_alloc - get a pointer to a genradix entry, allocating it
@@ -232,7 +252,13 @@ void *__genradix_ptr_alloc(struct __genradix *, size_t, gfp_t); 
	(__genradix_cast(_radix)				\

	 __genradix_ptr_alloc(&(_radix)->tree,			\

			__genradix_idx_to_offset(_radix, _idx),	\

			_gfp))

			NULL, _gfp))



#define genradix_ptr_alloc_preallocated(_radix, _idx, _new_node, _gfp)\

	(__genradix_cast(_radix)				\

	 __genradix_ptr_alloc(&(_radix)->tree,			\

			__genradix_idx_to_offset(_radix, _idx),	\

			_new_node, _gfp))



struct genradix_iter {

	size_t			offset;

lib/generic-radix-tree.c

+5 −11
Original line number Diff line number Diff line
@@ -15,27 +15,21 @@ void *__genradix_ptr(struct __genradix *radix, size_t offset) 
}

EXPORT_SYMBOL(__genradix_ptr);



static inline struct genradix_node *genradix_alloc_node(gfp_t gfp_mask)

{

	return kzalloc(GENRADIX_NODE_SIZE, gfp_mask);

}



static inline void genradix_free_node(struct genradix_node *node)

{

	kfree(node);

}



/*

 * Returns pointer to the specified byte @offset within @radix, allocating it if

 * necessary - newly allocated slots are always zeroed out:

 */

void *__genradix_ptr_alloc(struct __genradix *radix, size_t offset,

			   struct genradix_node **preallocated,

			   gfp_t gfp_mask)

{

	struct genradix_root *v = READ_ONCE(radix->root);

	struct genradix_node *n, *new_node = NULL;

	unsigned level;



	if (preallocated)

		swap(new_node, *preallocated);



	/* Increase tree depth if necessary: */

	while (1) {

		struct genradix_root *r = v, *new_root;
@@ -219,7 +213,7 @@ int __genradix_prealloc(struct __genradix *radix, size_t size, 
	size_t offset;



	for (offset = 0; offset < size; offset += GENRADIX_NODE_SIZE)

		if (!__genradix_ptr_alloc(radix, offset, gfp_mask))

		if (!__genradix_ptr_alloc(radix, offset, NULL, gfp_mask))

			return -ENOMEM;



	return 0;