rbtree: add RB_DECLARE_CALLBACKS() macro

As proposed by Peter Zijlstra, this makes it easier to define the augmented
rbtree callbacks.

Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michel Lespinasse 2012-10-08 16:31:21 -07:00 committed by Linus Torvalds
parent 9d9e6f9703
commit 3908836aa7
3 changed files with 34 additions and 67 deletions

View file

@ -79,6 +79,36 @@ rb_insert_augmented(struct rb_node *node, struct rb_root *root,
__rb_insert_augmented(node, root, augment->rotate);
}
#define RB_DECLARE_CALLBACKS(rbstatic, rbname, rbstruct, rbfield, \
rbtype, rbaugmented, rbcompute) \
static void rbname ## _propagate(struct rb_node *rb, struct rb_node *stop) \
{ \
while (rb != stop) { \
rbstruct *node = rb_entry(rb, rbstruct, rbfield); \
rbtype augmented = rbcompute(node); \
if (node->rbaugmented == augmented) \
break; \
node->rbaugmented = augmented; \
rb = rb_parent(&node->rbfield); \
} \
} \
static void rbname ## _copy(struct rb_node *rb_old, struct rb_node *rb_new) \
{ \
rbstruct *old = rb_entry(rb_old, rbstruct, rbfield); \
rbstruct *new = rb_entry(rb_new, rbstruct, rbfield); \
new->rbaugmented = old->rbaugmented; \
} \
static void rbname ## _rotate(struct rb_node *rb_old, struct rb_node *rb_new) \
{ \
rbstruct *old = rb_entry(rb_old, rbstruct, rbfield); \
rbstruct *new = rb_entry(rb_new, rbstruct, rbfield); \
new->rbaugmented = old->rbaugmented; \
old->rbaugmented = rbcompute(old); \
} \
rbstatic const struct rb_augment_callbacks rbname = { \
rbname ## _propagate, rbname ## _copy, rbname ## _rotate \
};
/* Find logical next and previous nodes in a tree */
extern struct rb_node *rb_next(const struct rb_node *);