From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Neukum Subject: Re: [PATCH 1/2 v5] usbnet: allow status interrupt URB to always be active Date: Thu, 11 Apr 2013 13:14:35 +0200 Message-ID: <28454387.MvMlbQoOly@linux-5eaq.site> References: <20110727141246.GC29616@orbit.nwl.cc> <3010836.mDNO71IiS7@linux-5eaq.site> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: Dan Williams , Elina Pasheva , Network Development , linux-usb , Rory Filer , Phil Sutter To: Ming Lei Return-path: Received: from smtp-out002.kontent.com ([81.88.40.216]:35853 "EHLO smtp-out002.kontent.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752127Ab3DKLNu (ORCPT ); Thu, 11 Apr 2013 07:13:50 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Thursday 11 April 2013 18:03:09 Ming Lei wrote: > On Thu, Apr 11, 2013 at 5:53 PM, Oliver Neukum wrote: > > On Thursday 11 April 2013 16:09:16 Ming Lei wrote: > >> > >> Could you explain why work queue need GFP_NOIO? > > > > Your fix for the memory allocation depends on it happening in the same > > context. If you execute code on a work queue this happens in the context > > of a kernel thread. > > I understand the interface might be called from workqueue, and my question > is why GFP_NOIO is needed in the work queue context. Generally speaking, > GFP_KERNEL is enough for work queue context. > > As we discussed before, GFP_NOIO is required in runtime resume context > and reset context, and the two contexts have been addressed automatically. > So looks you didn't answer my question, :-) Sorry, I misunderstood. Task A Task B queue queue work request a reset allocate memory and block cancel the work shit happened Regards Oliver