From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753397AbaIHLbl (ORCPT ); Mon, 8 Sep 2014 07:31:41 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:57109 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752925AbaIHLbj (ORCPT ); Mon, 8 Sep 2014 07:31:39 -0400 Date: Mon, 8 Sep 2014 13:31:29 +0200 From: Peter Zijlstra To: Alexander Shishkin Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Robert Richter , Frederic Weisbecker , Mike Galbraith , Paul Mackerras , Stephane Eranian , Andi Kleen , kan.liang@intel.com Subject: Re: [PATCH v4 04/22] perf: Add a capability for AUX_NO_SG pmus to do software double buffering Message-ID: <20140908113129.GC6758@twins.programming.kicks-ass.net> References: <1408538179-792-1-git-send-email-alexander.shishkin@linux.intel.com> <1408538179-792-5-git-send-email-alexander.shishkin@linux.intel.com> <20140908071712.GT19379@twins.programming.kicks-ass.net> <87oauqv09h.fsf@ashishki-desk.ger.corp.intel.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="gLeD4uI0NkB0GjLy" Content-Disposition: inline In-Reply-To: <87oauqv09h.fsf@ashishki-desk.ger.corp.intel.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --gLeD4uI0NkB0GjLy Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Sep 08, 2014 at 02:07:22PM +0300, Alexander Shishkin wrote: > Peter Zijlstra writes: > > In particular this looks like it will allocate double the total amount > > of pages and 'loose' half of them. There is no corresponding code in the > > free path to collect them. >=20 > This code makes the biggest high order allocation no bigger than half of > the total requested size. Then, when I allocate the high-order chunks, I > do a split_page() on them and everywhere else in the code they are > treated as individual pages, including the free path. So this patch has > no implication on freeing. Is this your concern? Ah right. I completely misread the patch. Sorry for the noise. --gLeD4uI0NkB0GjLy Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJUDZORAAoJEHZH4aRLwOS6elcP/3T36PwZYOwc5erdEMQ/0KuE J3LiQfx395cCF8/+KJ+GkxNLlsorTjeJXAKhx1PXxO5Zlh+M9xlVJhdKxrqZXC/s 5YbpMshURdCsJQhmcHrehJg4J6aRNDSelRP+wbcxMimrxD3maS0T+Uvcot7SfHk7 2PHvrCw6Mp10P6Us4pIJ2hAbXbA9cOic0lPsv0RRsFWPsFU+0pPBSyTMWQLmuPY+ l0YCuSi5HKzW2k7xN7WowKuN5AZcgyosByDbevx8US5rQilJkm0lvlHolmdfJlsu +FnB2GDcRQPX2PJ/Myh/nEakcs5dBBc0wz1gtfY1UnYGlHf4XRXfKu2hK9txggt+ trFFAzCHNbAcwwC5hi9KcoQEpp5REi46ZcDEXhweFZC09a9tC5dPofQa2guyu1FG CLJlKWEjJ8M1B4daKW0DuKFttfGjLLRRmwb5mRl6gkV6shiuyyGhK6h5/CZb2iG6 3EKYHJGdcWDTP0scrz+cB8RzTOBqV8zuemBFYDzqHnrjrdZpzaT/TkH6VXLla827 uJ3RBBuIXL/dyRAdLBsxa+q4LNFQsdtPP90WxK09JxtRk2ARe7HAwp968Ks1rQCv TgUlzmkjmR6ZBJhjAeVqeUQMzD8LzWyrGEQNUKQLFoQinubI/9zwU5RtV6picR/7 J6N2CW2SqvPVONZTXVTO =9E+k -----END PGP SIGNATURE----- --gLeD4uI0NkB0GjLy--