Commit c1297987 authored by Liam R. Howlett's avatar Liam R. Howlett Committed by Andrew Morton
Browse files

maple_tree: introduce __mas_set_range() 

mas_set_range() resets the node to MAS_START, which will cause a re-walk
of the tree to the range.  This is unnecessary when the maple state is
already at the correct location of the write.  Add a function that only
sets the range to avoid unnecessary re-walking of the tree.

Link: https://lkml.kernel.org/r/20230724183157.3939892-6-Liam.Howlett@oracle.com


Signed-off-by: default avatarLiam R. Howlett <Liam.Howlett@oracle.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 445a2ea0

include/linux/maple_tree.h

+18 −3
Original line number Diff line number Diff line
@@ -539,6 +539,22 @@ static inline void mas_reset(struct ma_state *mas) 
 */

#define mas_for_each(__mas, __entry, __max) \

	while (((__entry) = mas_find((__mas), (__max))) != NULL)

/**

 * __mas_set_range() - Set up Maple Tree operation state to a sub-range of the

 * current location.

 * @mas: Maple Tree operation state.

 * @start: New start of range in the Maple Tree.

 * @last: New end of range in the Maple Tree.

 *

 * set the internal maple state values to a sub-range.

 * Please use mas_set_range() if you do not know where you are in the tree.

 */

static inline void __mas_set_range(struct ma_state *mas, unsigned long start,

		unsigned long last)

{

	mas->index = start;

	mas->last = last;

}



/**

 * mas_set_range() - Set up Maple Tree operation state for a different index.
@@ -553,8 +569,7 @@ static inline void mas_reset(struct ma_state *mas) 
static inline

void mas_set_range(struct ma_state *mas, unsigned long start, unsigned long last)

{

	       mas->index = start;

	       mas->last = last;

	__mas_set_range(mas, start, last);

	mas->node = MAS_START;

}