Return-path: Received: from mail-we0-f171.google.com ([74.125.82.171]:50531 "EHLO mail-we0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762259AbbA3Nr2 convert rfc822-to-8bit (ORCPT ); Fri, 30 Jan 2015 08:47:28 -0500 Received: by mail-we0-f171.google.com with SMTP id k11so24841959wes.2 for ; Fri, 30 Jan 2015 05:47:27 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1422624670.1919.21.camel@sipsolutions.net> References: <1422607287-12289-1-git-send-email-michal.kazior@tieto.com> <1422621086-28970-1-git-send-email-michal.kazior@tieto.com> <1422621086-28970-3-git-send-email-michal.kazior@tieto.com> <1422621903.1919.7.camel@sipsolutions.net> <1422623054.1919.18.camel@sipsolutions.net> <1422624670.1919.21.camel@sipsolutions.net> Date: Fri, 30 Jan 2015 14:47:27 +0100 Message-ID: (sfid-20150130_145349_234208_577C773C) Subject: Re: [PATCH v2 2/7] ath10k: implement chanctx API From: Michal Kazior To: Johannes Berg Cc: "ath10k@lists.infradead.org" , linux-wireless Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On 30 January 2015 at 14:31, Johannes Berg wrote: > On Fri, 2015-01-30 at 14:22 +0100, Michal Kazior wrote: > >> You'd probably have to add quite a few mutex_lock(iflist_mtx) around >> drv_*() calls (not directly but somewhere at their call trees) to >> guarantee driver can use lock-free iterate() version (which doesn't >> exist yet). This could be tricky. > > Well, I was thinking you'd only use it in some places now - but it does > seem a bit difficult to maintain. > > We've not typically had to worry about using the synchronous versions > much since we mostly just need a single interface so we just pass it out > and use it there, or so. I'm not sure if you refer to iwlwifi or mac80211 now? If it's the latter: even if you have an ops with, e.g. vif pointer, driver may still need to iterate over interfaces in order to propagate some side-effect changes or aggregate some values/recalculate. Michał