Return-path: Received: from mms1.broadcom.com ([216.31.210.17]:2149 "EHLO mms1.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750916Ab2JSIAw (ORCPT ); Fri, 19 Oct 2012 04:00:52 -0400 Message-ID: <508108AB.2010801@broadcom.com> (sfid-20121019_100056_543372_F0519641) Date: Fri, 19 Oct 2012 10:00:43 +0200 From: "Arend van Spriel" MIME-Version: 1.0 To: "Bing Zhao" cc: "linux-wireless@vger.kernel.org" , "Johannes Berg" , "John W. Linville" , "Sam Leffler" , "Amitkumar Karwar" Subject: Re: [PATCH v6 3/6] cfg80211: add scan flag to indicate its priority References: <1350542071-26498-1-git-send-email-bzhao@marvell.com> <1350542071-26498-4-git-send-email-bzhao@marvell.com> <507FAF19.6030500@broadcom.com> <477F20668A386D41ADCC57781B1F7043083B80E682@SC-VEXCH1.marvell.com> In-Reply-To: <477F20668A386D41ADCC57781B1F7043083B80E682@SC-VEXCH1.marvell.com> Content-Type: text/plain; charset=iso-8859-1; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 10/18/2012 08:44 PM, Bing Zhao wrote: > Hi Arend, > >>> From: Sam Leffler >>> >>> Add NL80211_SCAN_FLAG_LOW_PRIORITY flag support. It tells drivers >>> that this is a low priority scan request, so that they can take >>> necessary action. >>> Drivers need to advertise low priority scan capability during >>> registration. >> >> I missed the previous versions of this patch series, but what 'necessary >> action' is needed for a low priority scan request. Patch #6 gives a clue >> so my assumption is that a low prio scan will be *aborted* when >> associated and data traffic is available. Is that correct? Could it also > > It's up to the driver to decide and implement the 'low priority scan' feature. > The driver can defer or abort the low priority scan request depending on various conditions. > For example, when heavy data traffic is on going you may want to abort the scan. Thanks, Bing I always find such answer tricky. Seeing where this is coming from I suspect there is some high-level expectation from user-space perspective. I suspect it is something like: A low-prio scan should not affect a data transfer (iperf, nfs i/o, etc.) noticably. Thanks for collecting the reading material ;-) Gr. AvS