diff options
| author | Wei Yang <richardw.yang@linux.intel.com> | 2019-12-04 16:51:47 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-12-04 19:44:13 -0800 |
| commit | 11d43e62f693c66c8c76c2ea2349e0f3c5764964 (patch) | |
| tree | c9ee0fa1a402360641bc1d0275961a8ac87cea04 /include | |
| parent | ae81217edc18135d13e5b6c17609ee2c07af4188 (diff) | |
| download | linux-11d43e62f693c66c8c76c2ea2349e0f3c5764964.tar.bz2 | |
lib/rbtree: set successor's parent unconditionally
Both in Case 2 and 3, we exchange n and s. This mean no matter whether
child2 is NULL or not, successor's parent should be assigned to node's.
This patch takes this step out to make it explicit and reduce the
ambiguity.
Besides, this step reduces some symbol size like rb_erase().
KERN_CONFIG upstream patched
OPT_FOR_PERF 877 870
OPT_FOR_SIZE 635 621
Link: http://lkml.kernel.org/r/20191028021442.5450-1-richardw.yang@linux.intel.com
Signed-off-by: Wei Yang <richardw.yang@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/rbtree_augmented.h | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/include/linux/rbtree_augmented.h b/include/linux/rbtree_augmented.h index fdd421b8d9ae..99c42e1a74b8 100644 --- a/include/linux/rbtree_augmented.h +++ b/include/linux/rbtree_augmented.h @@ -283,14 +283,13 @@ __rb_erase_augmented(struct rb_node *node, struct rb_root *root, __rb_change_child(node, successor, tmp, root); if (child2) { - successor->__rb_parent_color = pc; rb_set_parent_color(child2, parent, RB_BLACK); rebalance = NULL; } else { unsigned long pc2 = successor->__rb_parent_color; - successor->__rb_parent_color = pc; rebalance = __rb_is_black(pc2) ? parent : NULL; } + successor->__rb_parent_color = pc; tmp = successor; } |