From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH] mk: fix kernel modules build dependency Date: Fri, 30 Mar 2018 10:32:30 +0200 Message-ID: <13988753.3FnxEl37g3@xps> References: <20180329153931.26351-1-thomas@monjalon.net> <79a33084-a6fc-d04a-a503-3c8cc15a58b2@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: hemant.agrawal@nxp.com, dev@dpdk.org To: Ferruh Yigit Return-path: Received: from out5-smtp.messagingengine.com (out5-smtp.messagingengine.com [66.111.4.29]) by dpdk.org (Postfix) with ESMTP id 8FFC72E81 for ; Fri, 30 Mar 2018 10:32:54 +0200 (CEST) In-Reply-To: List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 29/03/2018 20:43, Ferruh Yigit: > On 3/29/2018 7:21 PM, Ferruh Yigit wrote: > > On 3/29/2018 6:01 PM, Thomas Monjalon wrote: > >> 29/03/2018 18:50, Ferruh Yigit: > >>> On 3/29/2018 5:43 PM, Thomas Monjalon wrote: > >>>> 29/03/2018 18:38, Ferruh Yigit: > >>>>> On 3/29/2018 5:32 PM, Thomas Monjalon wrote: > >>>>>> 29/03/2018 17:48, Ferruh Yigit: > >>>>>>> On 3/29/2018 4:39 PM, Thomas Monjalon wrote: > >>>>>>>> Some kernel modules may need some header files to be "installed" > >>>>>>>> in the build directory. > >>>>>>>> > >>>>>>>> When running multiple threads of make, kernel modules can try to > >>>>>>>> be compiled before the lib headers are ready: > >>>>>>>> make -j3 > >>>>>>>> kernel/linux/kni/kni_misc.c:19:37: fatal error: > >>>>>>>> exec-env/rte_kni_common.h: No such file or directory > >>>>>>> > >>>>>>> Is there a reason to keep header in eal when module itself moved into kernel? > >>>>>> > >>>>>> It seems you missed my comment below: > >>>>>> > >>>>>> On a related note, this header file > >>>>>> lib/librte_eal/linuxapp/eal/include/exec-env/rte_kni_common.h > >>>>>> could be moved to lib/librte_kni/ > >>>>>> Opinion? > >>>>> > >>>>> Ahh, yes we are saying same thing. > >>>>> But not sure if it should go under lib/librte_kni/ or kernel/linux/kni/? > >>>>> I lean to kernel/linux/kni/. > >>>> > >>>> Why in kernel/? > >>>> > >>>> Logically, kernel/ depends on lib/ but not the reverse. > >>>> > >>>> And regarding the licensing, we avoid BSD files in Linux modules. > >>> > >>> From functionality point of view, module provides the functionality and it > >>> should provide the header, this can be all subjective tough :) > >>> > >>> Or in other words, if you have the kernel module, you can write another piece of > >>> userspace application (without using librte_kni) and it will be functional. > >>> But if you have the librte_kni only, it won't be functional on its own. > >>> > >>> Providing header with kernel enables other userspace app to user KNI. > >> > >> So you are saying we should reverse the dependency? > >> It would mean moving all headers used by kernel modules in kernel/ directory: > > > > No, not talking about moving headers to kernel/ folder. But we can "liberate" J > > the kernel modules. > > > > For KNI, rte_kni_common.h is shared between kernel and userspace, can't escape > > from it. But why this common header needs to depend other dpdk headers at all? > > Indeed commenting out rte_common and rte_config worked fine, it seem there is > > already no dependency. > > Hemant is right, putting rte_kni_common makes build dependent to module build, > and module is more fragile. > > I agree to move header to userspace library. Does it mean you ack this patch? Do you want to make a patch to move the header from EAL to librte_kni?