From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx179.postini.com [74.125.245.179]) by kanga.kvack.org (Postfix) with SMTP id 588926B0044 for ; Mon, 6 Aug 2012 10:18:00 -0400 (EDT) Message-ID: <1344262669.27828.55.camel@twins> Subject: Re: [PATCH v2 8/9] rbtree: faster augmented rbtree manipulation From: Peter Zijlstra Date: Mon, 06 Aug 2012 16:17:49 +0200 In-Reply-To: <1343946858-8170-9-git-send-email-walken@google.com> References: <1343946858-8170-1-git-send-email-walken@google.com> <1343946858-8170-9-git-send-email-walken@google.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Michel Lespinasse Cc: riel@redhat.com, daniel.santos@pobox.com, aarcange@redhat.com, dwmw2@infradead.org, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, torvalds@linux-foundation.org On Thu, 2012-08-02 at 15:34 -0700, Michel Lespinasse wrote: > +static void augment_propagate(struct rb_node *rb, struct rb_node *stop) > +{ > + while (rb !=3D stop) { > + struct interval_tree_node *node =3D > + rb_entry(rb, struct interval_tree_node, rb); > + unsigned long subtree_last =3D compute_subtree_last(node)= ; > + if (node->__subtree_last =3D=3D subtree_last) > + break; > + node->__subtree_last =3D subtree_last; > + rb =3D rb_parent(&node->rb); > + } > +} > + > +static void augment_copy(struct rb_node *rb_old, struct rb_node *rb_new) > +{ > + struct interval_tree_node *old =3D > + rb_entry(rb_old, struct interval_tree_node, rb); > + struct interval_tree_node *new =3D > + rb_entry(rb_new, struct interval_tree_node, rb); > + > + new->__subtree_last =3D old->__subtree_last; > +} > + > +static void augment_rotate(struct rb_node *rb_old, struct rb_node *rb_ne= w) > +{ > + struct interval_tree_node *old =3D > + rb_entry(rb_old, struct interval_tree_node, rb); > + struct interval_tree_node *new =3D > + rb_entry(rb_new, struct interval_tree_node, rb); > + > + new->__subtree_last =3D old->__subtree_last; > + old->__subtree_last =3D compute_subtree_last(old); > +}=20 I still don't get why we need the 3 callbacks when both propagate and rotate are simple variants of the original callback (compute_subtree_last, in this instance). Why would every user need to replicate the propagate and rotate boilerplate? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org