From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:39930) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UamFs-0003mk-Eo for qemu-devel@nongnu.org; Fri, 10 May 2013 08:16:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UamFr-0007jS-24 for qemu-devel@nongnu.org; Fri, 10 May 2013 08:16:56 -0400 Received: from mail-wg0-x22d.google.com ([2a00:1450:400c:c00::22d]:44188) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UamFq-0007jM-TC for qemu-devel@nongnu.org; Fri, 10 May 2013 08:16:55 -0400 Received: by mail-wg0-f45.google.com with SMTP id l18so4091400wgh.12 for ; Fri, 10 May 2013 05:16:54 -0700 (PDT) Sender: Paolo Bonzini From: Paolo Bonzini Date: Fri, 10 May 2013 14:16:37 +0200 Message-Id: <1368188203-3407-4-git-send-email-pbonzini@redhat.com> In-Reply-To: <1368188203-3407-1-git-send-email-pbonzini@redhat.com> References: <1368188203-3407-1-git-send-email-pbonzini@redhat.com> Subject: [Qemu-devel] [PATCH for-1.5 3/9] qom: add a fast path to object_class_dynamic_cast List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Anthony Liguori , Andreas Faerber , Aurelien Jarno , mst@redhat.com For leaf classes, in many cases the callbacks will simply downcast the object back to the original class. Add this fast path to object_class_dynamic_cast, object_dynamic_cast will inherit it. Signed-off-by: Paolo Bonzini --- qom/object.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/qom/object.c b/qom/object.c index 35f4694..0aa0c07 100644 --- a/qom/object.c +++ b/qom/object.c @@ -457,7 +457,12 @@ ObjectClass *object_class_dynamic_cast(ObjectClass *class, return NULL; } + /* A simple fast path that can trigger a lot for leaf classes. */ type = class->type; + if (type->name == typename) { + return class; + } + target_type = type_get_by_name(typename); if (!target_type) { /* target class type unknown, so fail the cast */ -- 1.8.1.4