From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from he.sipsolutions.net ([78.46.109.217]:47999 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751869Ab1I2J7s (ORCPT ); Thu, 29 Sep 2011 05:59:48 -0400 Subject: Re: [PATCH] mac80211: Allow NO_ACK flag overwrite for injected frames From: Johannes Berg To: Helmut Schaa Cc: linux-wireless@vger.kernel.org, linville@tuxdriver.com In-Reply-To: <1317288432-26380-1-git-send-email-helmut.schaa@googlemail.com> (sfid-20110929_112749_887836_A27DE080) References: <1317288432-26380-1-git-send-email-helmut.schaa@googlemail.com> (sfid-20110929_112749_887836_A27DE080) Content-Type: text/plain; charset="UTF-8" Date: Thu, 29 Sep 2011 11:59:35 +0200 Message-ID: <1317290375.3974.1.camel@jlt3.sipsolutions.net> (sfid-20110929_115951_929105_4F9AE0DF) Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Thu, 2011-09-29 at 11:27 +0200, Helmut Schaa wrote: > Allow injected unicast frames to be sent without having to wait > for an ACK. > > Signed-off-by: Helmut Schaa > --- > > Just in case you're interested in what's the intended purpose of this: > > Some clients are staying on scanned channels for a very short period of > time. hostapd sends out probe responses for each configured BSSID. Under > some circumstances I can see that the client already left the channel > while some probe responses are still sent out and thus retried. This > consumes quite some airtime. Commercial wireless APs (Aruba for example) > seem to disable retries for probe responses to mitigate such issues. Makes sense, but I wonder if we really should continue using radiotap :-) Maybe mgmt-tx in nl80211 would be appropriate. > @@ -1257,7 +1265,7 @@ ieee80211_tx_prepare(struct ieee80211_sub_if_data *sdata, > tx->flags |= IEEE80211_TX_UNICAST; > if (unlikely(local->wifi_wme_noack_test)) > info->flags |= IEEE80211_TX_CTL_NO_ACK; > - else > + else if (!(info->flags & IEEE80211_TX_CTL_NO_ACK)) > info->flags &= ~IEEE80211_TX_CTL_NO_ACK; ?? johannes