From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EDA85CA9EA0 for ; Fri, 18 Oct 2019 14:07:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C0222222C3 for ; Fri, 18 Oct 2019 14:07:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2501882AbfJROHY (ORCPT ); Fri, 18 Oct 2019 10:07:24 -0400 Received: from s3.sipsolutions.net ([144.76.43.62]:58630 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2408322AbfJROHX (ORCPT ); Fri, 18 Oct 2019 10:07:23 -0400 Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.92.2) (envelope-from ) id 1iLSuX-0004Ql-P7; Fri, 18 Oct 2019 16:07:21 +0200 Message-ID: Subject: Re: [PATCH v2 1/4] mac80211: Rearrange ieee80211_tx_info to make room for tx_time_est From: Johannes Berg To: Toke =?ISO-8859-1?Q?H=F8iland-J=F8rgensen?= , Kan Yan Cc: linux-wireless@vger.kernel.org, make-wifi-fast@lists.bufferbloat.net, ath10k@lists.infradead.org, John Crispin , Lorenzo Bianconi , Felix Fietkau , Rajkumar Manoharan , Kevin Hayes Date: Fri, 18 Oct 2019 16:07:20 +0200 In-Reply-To: <87d0eudufu.fsf@toke.dk> References: <157115993755.2500430.12214017471129215800.stgit@toke.dk> <157115993866.2500430.13989567853855880476.stgit@toke.dk> <87sgnqe4wg.fsf@toke.dk> <10b885b3238cede2d99c6134bebcc0c8ba6f6b10.camel@sipsolutions.net> <87imomdvsj.fsf@toke.dk> <9fc60b546b54b40357264d67536733251cf39ebe.camel@sipsolutions.net> <87d0eudufu.fsf@toke.dk> Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.30.5 (3.30.5-1.fc29) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On Fri, 2019-10-18 at 16:01 +0200, Toke Høiland-Jørgensen wrote: > Right. Well in that case, let's try it. As long as we fail in a > reasonable way, we can just see if we run into anything that breaks? I > guess in this case that means rejecting requests from userspace if we > run out of IDs rather than silently wrapping and returning wrong data :) We can't reject due to how this works, but if the idr_alloc() fails then we'll just not give a status back to userspace later. > > > We could also split 5/11. That would support up to 32 ACK IDs, and we > > > can just truncate the airtime at 2048 us, which is not a big deal I'd > > > say. > > > > We can also play with the units of the airtime, e.g. making that a > > multiple of 2 or 4 us? Seems unlikely to matter much? > > Sure, that's a good point! Increments of 4us means we can fit 4ms is 10 > bits, leaving plenty of space for ACK IDs (hopefully). > > I'll rework the series to use that instead :) OK. There are two places that call idr_alloc() with a hardcoded limit of 0x10000, you'll have to fix those to have the right limit according to the bits you leave for the ACK id. johannes