From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932185AbZDJKYj (ORCPT ); Fri, 10 Apr 2009 06:24:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1764686AbZDJKYH (ORCPT ); Fri, 10 Apr 2009 06:24:07 -0400 Received: from mail.gmx.net ([213.165.64.20]:48682 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1764457AbZDJKYG (ORCPT ); Fri, 10 Apr 2009 06:24:06 -0400 Cc: akpm@linux-foundation.org, peterz@infradead.org, lowdanie@gmail.com Content-Type: text/plain; charset="iso-8859-1" Date: Fri, 10 Apr 2009 12:24:04 +0200 From: "Wolfram Strepp" Message-ID: <20090410102404.247130@gmx.net> MIME-Version: 1.0 Subject: [PATCH 3/3] Further optimization of function rb_erase() in lib/rbtree.c To: linux-kernel@vger.kernel.org X-Authenticated: #14768304 X-Flags: 0001 X-Mailer: WWW-Mail 6100 (Global Message Exchange) X-Priority: 3 X-Provags-ID: V01U2FsdGVkX18ycw49830yg5/kI4h23ZWOqkYIax0bFKYBuYt4+I Zp4ezKr5B49c0R4ndd2Y9wY3cfKoZfpJ8O9w== Content-Transfer-Encoding: 8bit X-GMX-UID: Inq3BLIBbHIhesJg2DQ0f2oiJihyahCD X-FuHaFi: 0.64 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Furthermore, notice that the initial checks: if (!node->rb_left) child = node->rb_right; else if (!node->rb_right) child = node->rb_left; else { ... } guarantee that old->rb_right is set in the final else branch, therefore we can omit checking that again. Signed-off-by: Wolfram Strepp Signed-off-by: Peter Zijlstra --- lib/rbtree.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) Index: linux-2.6/lib/rbtree.c =================================================================== --- linux-2.6.orig/lib/rbtree.c +++ linux-2.6/lib/rbtree.c @@ -257,15 +257,15 @@ void rb_erase(struct rb_node *node, stru if (child) rb_set_parent(child, parent); parent->rb_left = child; + + node->rb_right = old->rb_right; + rb_set_parent(old->rb_right, node); } node->rb_parent_color = old->rb_parent_color; - node->rb_right = old->rb_right; node->rb_left = old->rb_left; - rb_set_parent(old->rb_left, node); - if (old->rb_right) - rb_set_parent(old->rb_right, node); + goto color; } -- Psssst! Schon vom neuen GMX MultiMessenger gehört? Der kann`s mit allen: http://www.gmx.net/de/go/multimessenger01