From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from charlotte.tuxdriver.com ([70.61.120.58]:54079 "EHLO smtp.tuxdriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750760Ab0JGPaG (ORCPT ); Thu, 7 Oct 2010 11:30:06 -0400 Date: Thu, 7 Oct 2010 11:27:09 -0400 From: "John W. Linville" To: Johannes Berg Cc: linux-wireless@vger.kernel.org Subject: Re: [PATCH 2/2] mac80211: use netif_receive_skb in ieee80211_tx_status callpath Message-ID: <20101007152708.GA20950@tuxdriver.com> References: <1277405253-23735-1-git-send-email-linville@tuxdriver.com> <1286457360.20974.1.camel@jlt3.sipsolutions.net> <1286457457.20974.2.camel@jlt3.sipsolutions.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1286457457.20974.2.camel@jlt3.sipsolutions.net> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Thu, Oct 07, 2010 at 03:17:37PM +0200, Johannes Berg wrote: > On Thu, 2010-10-07 at 15:16 +0200, Johannes Berg wrote: > > On Thu, 2010-06-24 at 14:47 -0400, John W. Linville wrote: > > > This avoids the extra queueing from calling netif_rx. > > > > John, can you please revert this? It's causing issues because we don't > > necessarily have BHs disabled here with all drivers (see below). > > Depending on the RCU implementation, it might disable BHs, but not all > > of them do or need to. > > > > Alternatively, we can require drivers to call ieee80211_tx_status() with > > BHs disabled, but somebody would have to go through them... > > For RX, we do this with ieee80211_rx_ni(). Right. I thought I had checked all these contexts, but ath9k in particular is a bit complicated to trace all the potential callpaths by hand. I'll revert it, and the rtl8180 patch to use napi (which also does tx status in that context). John -- John W. Linville Someday the world will need a hero, and you linville@tuxdriver.com might be all we have. Be ready.