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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 B301BCA9EA0 for ; Fri, 18 Oct 2019 13:01:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8C3F2222C5 for ; Fri, 18 Oct 2019 13:01:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=candelatech.com header.i=@candelatech.com header.b="jxDuiSzx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2410200AbfJRNB1 (ORCPT ); Fri, 18 Oct 2019 09:01:27 -0400 Received: from mail2.candelatech.com ([208.74.158.173]:60632 "EHLO mail3.candelatech.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2410165AbfJRNB0 (ORCPT ); Fri, 18 Oct 2019 09:01:26 -0400 Received: from [192.168.1.47] (unknown [50.34.216.97]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail3.candelatech.com (Postfix) with ESMTPSA id 54019137566; Fri, 18 Oct 2019 06:01:24 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 mail3.candelatech.com 54019137566 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=candelatech.com; s=default; t=1571403685; bh=05vVSmqtLW47sf9Rc6MdFNX56EEXBS4FCPBzksR0BBU=; h=Subject:To:References:Cc:From:Date:In-Reply-To:From; b=jxDuiSzx/ZZgjhMYWzw/B71/TOWFpvnWECNzIr6qxryERkzE1+Fw9kS1pqDf/yr3o IGFVVCEcNuMXsBkhxj2jqgpXAM0r3i7bhotOF0WDtqVhi0D+JskMCsNC65jXKiYbnz 0kvJfMOB4fPHiXbEddzWdHBOLHGo0BbujnDa1e3E= Subject: Re: [PATCH v2 1/4] mac80211: Rearrange ieee80211_tx_info to make room for tx_time_est To: Johannes Berg , =?UTF-8?Q?Toke_H=c3=b8iland-J=c3=b8rgensen?= , Kan Yan References: <157115993755.2500430.12214017471129215800.stgit@toke.dk> <157115993866.2500430.13989567853855880476.stgit@toke.dk> <87sgnqe4wg.fsf@toke.dk> <4bc17c32337888a57a78a0e2c874abd462faef21.camel@sipsolutions.net> 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 From: Ben Greear Message-ID: <237a3110-69c1-6679-6ffb-892c3815049c@candelatech.com> Date: Fri, 18 Oct 2019 06:01:23 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <4bc17c32337888a57a78a0e2c874abd462faef21.camel@sipsolutions.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On 10/18/2019 05:35 AM, Johannes Berg wrote: > On Fri, 2019-10-18 at 12:15 +0200, Toke Høiland-Jørgensen wrote: >> Kan Yan writes: >> >>> The "tx_time_est" field, shared by control and status, is not able to >>> survive until the skb returns to the mac80211 layer in some >>> architectures. The same space is defined as driver_data and some >>> wireless drivers use it for other purposes, as the cb in the sk_buff >>> is free to be used by any layer. >>> >>> In the case of ath10k, the tx_time_est get clobbered by >>> struct ath10k_skb_cb { >>> dma_addr_t paddr; >>> u8 flags; >>> u8 eid; >>> u16 msdu_id; >>> u16 airtime_est; >>> struct ieee80211_vif *vif; >>> struct ieee80211_txq *txq; >>> } __packed; >> >> Ah, bugger, of course the driver that actually needs this is using the >> full driver_data space :P > > Looks like you could shrink *this* fairly easily though. > > E.g. most likely vif == txq->vif unless txq==NULL, so it's down to 22 > bytes plus a bit/flag for knowing whether the pointer is a vif directly > (if no TXQ) or a TXQ. And of course you get two bits in every pointer (0x3) and likely the dma addr too. Plenty of space! Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail2.candelatech.com ([208.74.158.173] helo=mail3.candelatech.com) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iLRsl-00031Y-Jy for ath10k@lists.infradead.org; Fri, 18 Oct 2019 13:01:29 +0000 Subject: Re: [PATCH v2 1/4] mac80211: Rearrange ieee80211_tx_info to make room for tx_time_est References: <157115993755.2500430.12214017471129215800.stgit@toke.dk> <157115993866.2500430.13989567853855880476.stgit@toke.dk> <87sgnqe4wg.fsf@toke.dk> <4bc17c32337888a57a78a0e2c874abd462faef21.camel@sipsolutions.net> From: Ben Greear Message-ID: <237a3110-69c1-6679-6ffb-892c3815049c@candelatech.com> Date: Fri, 18 Oct 2019 06:01:23 -0700 MIME-Version: 1.0 In-Reply-To: <4bc17c32337888a57a78a0e2c874abd462faef21.camel@sipsolutions.net> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: base64 Content-Type: text/plain; charset="utf-8"; Format="flowed" Sender: "ath10k" Errors-To: ath10k-bounces+kvalo=adurom.com@lists.infradead.org To: Johannes Berg , =?UTF-8?Q?Toke_H=c3=b8iland-J=c3=b8rgensen?= , Kan Yan Cc: Rajkumar Manoharan , Kevin Hayes , make-wifi-fast@lists.bufferbloat.net, linux-wireless@vger.kernel.org, ath10k@lists.infradead.org, John Crispin , Lorenzo Bianconi , Felix Fietkau CgpPbiAxMC8xOC8yMDE5IDA1OjM1IEFNLCBKb2hhbm5lcyBCZXJnIHdyb3RlOgo+IE9uIEZyaSwg MjAxOS0xMC0xOCBhdCAxMjoxNSArMDIwMCwgVG9rZSBIw7hpbGFuZC1Kw7hyZ2Vuc2VuIHdyb3Rl Ogo+PiBLYW4gWWFuIDxreWFuQGdvb2dsZS5jb20+IHdyaXRlczoKPj4KPj4+IFRoZSAidHhfdGlt ZV9lc3QiIGZpZWxkLCBzaGFyZWQgYnkgY29udHJvbCBhbmQgc3RhdHVzLCBpcyBub3QgYWJsZSB0 bwo+Pj4gc3Vydml2ZSB1bnRpbCB0aGUgc2tiIHJldHVybnMgdG8gdGhlIG1hYzgwMjExIGxheWVy IGluIHNvbWUKPj4+IGFyY2hpdGVjdHVyZXMuIFRoZSBzYW1lIHNwYWNlIGlzIGRlZmluZWQgYXMg ZHJpdmVyX2RhdGEgYW5kIHNvbWUKPj4+IHdpcmVsZXNzIGRyaXZlcnMgdXNlIGl0IGZvciBvdGhl ciBwdXJwb3NlcywgYXMgdGhlIGNiIGluIHRoZSBza19idWZmCj4+PiBpcyBmcmVlIHRvIGJlIHVz ZWQgYnkgYW55IGxheWVyLgo+Pj4KPj4+IEluIHRoZSBjYXNlIG9mIGF0aDEwaywgdGhlIHR4X3Rp bWVfZXN0IGdldCBjbG9iYmVyZWQgYnkKPj4+IHN0cnVjdCBhdGgxMGtfc2tiX2NiIHsKPj4+ICAg ICAgICAgZG1hX2FkZHJfdCBwYWRkcjsKPj4+ICAgICAgICAgdTggZmxhZ3M7Cj4+PiAgICAgICAg IHU4IGVpZDsKPj4+ICAgICAgICAgdTE2IG1zZHVfaWQ7Cj4+PiAgICAgICAgIHUxNiBhaXJ0aW1l X2VzdDsKPj4+ICAgICAgICAgc3RydWN0IGllZWU4MDIxMV92aWYgKnZpZjsKPj4+ICAgICAgICAg c3RydWN0IGllZWU4MDIxMV90eHEgKnR4cTsKPj4+IH0gX19wYWNrZWQ7Cj4+Cj4+IEFoLCBidWdn ZXIsIG9mIGNvdXJzZSB0aGUgZHJpdmVyIHRoYXQgYWN0dWFsbHkgbmVlZHMgdGhpcyBpcyB1c2lu ZyB0aGUKPj4gZnVsbCBkcml2ZXJfZGF0YSBzcGFjZSA6UAo+Cj4gTG9va3MgbGlrZSB5b3UgY291 bGQgc2hyaW5rICp0aGlzKiBmYWlybHkgZWFzaWx5IHRob3VnaC4KPgo+IEUuZy4gbW9zdCBsaWtl bHkgdmlmID09IHR4cS0+dmlmIHVubGVzcyB0eHE9PU5VTEwsIHNvIGl0J3MgZG93biB0byAyMgo+ IGJ5dGVzIHBsdXMgYSBiaXQvZmxhZyBmb3Iga25vd2luZyB3aGV0aGVyIHRoZSBwb2ludGVyIGlz IGEgdmlmIGRpcmVjdGx5Cj4gKGlmIG5vIFRYUSkgb3IgYSBUWFEuCgpBbmQgb2YgY291cnNlIHlv dSBnZXQgdHdvIGJpdHMgaW4gZXZlcnkgcG9pbnRlciAoMHgzKSBhbmQgbGlrZWx5IHRoZQpkbWEg YWRkciB0b28uICBQbGVudHkgb2Ygc3BhY2UhCgpUaGFua3MsCkJlbgoKLS0gCkJlbiBHcmVlYXIg PGdyZWVhcmJAY2FuZGVsYXRlY2guY29tPgpDYW5kZWxhIFRlY2hub2xvZ2llcyBJbmMgIGh0dHA6 Ly93d3cuY2FuZGVsYXRlY2guY29tCgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fXwphdGgxMGsgbWFpbGluZyBsaXN0CmF0aDEwa0BsaXN0cy5pbmZyYWRlYWQu b3JnCmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8vYXRoMTBrCg==