From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.tuxdriver.com (charlotte.tuxdriver.com [70.61.120.58]) by dpdk.org (Postfix) with ESMTP id 338C85A95 for ; Fri, 13 Mar 2015 16:19:12 +0100 (CET) Received: from hmsreliant.think-freely.org ([2001:470:8:a08:7aac:c0ff:fec2:933b] helo=localhost) by smtp.tuxdriver.com with esmtpsa (TLSv1:AES128-SHA:128) (Exim 4.63) (envelope-from ) id 1YWRMV-0007os-Ur; Fri, 13 Mar 2015 11:19:08 -0400 Date: Fri, 13 Mar 2015 11:18:55 -0400 From: Neil Horman To: Stefan Puiu Message-ID: <20150313151855.GG28191@hmsreliant.think-freely.org> References: <1422544811-26385-1-git-send-email-sergio.gonzalez.monroy@intel.com> <1426177681-16931-1-git-send-email-sergio.gonzalez.monroy@intel.com> <1426177681-16931-2-git-send-email-sergio.gonzalez.monroy@intel.com> <5502C7D9.2060503@intel.com> <5502CEAB.8060801@intel.com> <20150313131719.GA28191@hmsreliant.think-freely.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-Spam-Score: -2.9 (--) X-Spam-Status: No Cc: "dev@dpdk.org" Subject: Re: [dpdk-dev] [PATCH v2 1/4] mk: Remove combined library and related options X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 13 Mar 2015 15:19:12 -0000 On Fri, Mar 13, 2015 at 04:12:35PM +0200, Stefan Puiu wrote: > Hi, > > 2 cents from a DPDK library user - I make 2 changes to the default > linux+gcc configuration: combine libraries and build shared libraries > (since I want 2 instances of the app, it didn't make sense to me to > link statically). I tried working with the individual libs, but adding > all of them with --start-group/-end-group just seemed so much more > painful than simply linking against one lib. I know there are some > Makefile variables to help with this, but I use scons for building my > app, so that doesn't help much. > > Of course, if that can be achieved easily after building all the > libraries, that's fine. But I think combining the libs makes a lot of > sense in many cases. > So do it, create a linker script that internally contains one line: INPUT(-lrte_eal -lrte_alarm -lrte_mempool ... etc) Name the file libdpdk.so then when you build your app, just link -ldpdk Done. Neil > Thanks, > Stefan. > > On Fri, Mar 13, 2015 at 3:17 PM, Neil Horman wrote: > > On Fri, Mar 13, 2015 at 11:48:59AM +0000, Gonzalez Monroy, Sergio wrote: > >> On 13/03/2015 11:34, Kavanagh, Mark B wrote: > >> >>On 13/03/2015 10:49, Kavanagh, Mark B wrote: > >> >>>>--- > >> >>>>config/common_bsdapp | 6 -- > >> >>>>config/common_linuxapp | 6 -- > >> >>>>config/defconfig_ppc_64-power8-linuxapp-gcc | 2 - > >> >>>>lib/Makefile | 1 - > >> >>>>mk/rte.app.mk | 12 ---- > >> >>>>mk/rte.lib.mk | 35 ---------- > >> >>>>mk/rte.sdkbuild.mk | 3 - > >> >>>>mk/rte.sharelib.mk | 101 ---------------------------- > >> >>>>mk/rte.vars.mk | 9 --- > >> >>>>9 files changed, 175 deletions(-) > >> >>>>delete mode 100644 mk/rte.sharelib.mk > >> >>>> > >> >>>>diff --git a/config/common_bsdapp b/config/common_bsdapp > >> >>>>index 8ff4dc2..7ee5ecf 100644 > >> >>>>--- a/config/common_bsdapp > >> >>>>+++ b/config/common_bsdapp > >> >>>>@@ -79,12 +79,6 @@ CONFIG_RTE_FORCE_INTRINSICS=n > >> >>>>CONFIG_RTE_BUILD_SHARED_LIB=n > >> >>>> > >> >>>># > >> >>>>-# Combine to one single library > >> >>>>-# > >> >>>>-CONFIG_RTE_BUILD_COMBINE_LIBS=n > >> >>>>-CONFIG_RTE_LIBNAME=intel_dpdk > >> >>>Hi Sergio, > >> >>> > >> >>>Removing these options breaks compatibility with OVS. While it may be feasible to link > >> >>to individual static libraries, in our experience, a single combined library provides a > >> >>much more convenient way of linking. > >> >>>Thanks, > >> >>>Mark > >> >>> > >> >>>>- > >> > > >> >(snip) > >> > > >> > > >> >>>>-endif > >> >>>>- > >> >>>>-RTE_LIBNAME := $(CONFIG_RTE_LIBNAME:"%"=%) > >> >>>>-ifeq ($(RTE_LIBNAME),) > >> >>>>-RTE_LIBNAME := intel_dpdk > >> >>>>endif > >> >>>> > >> >>>># RTE_TARGET is deducted from config when we are building the SDK. > >> >>>>-- > >> >>>>1.9.3 > >> >>Hi Mark, > >> >> > >> >>How does this patch break compatibility with OVS? > >> >> > >> >>Thanks, > >> >>Sergio > >> >Hey Sergio, > >> > > >> >We use the CONFIG_RTE_BUILD_COMBINE_LIBS and CONFIG_RTE_LINBNAME flags to build a single static DPDK library, named 'libintel_dpdk.a', which OVS links against. Removing the combined library option breaks compatibility with any application that links against the combined DPDK library. > >> > > >> >Is there a strong technical motivation for removing these options? > >> > > >> >Thanks, > >> >Mark > >> From a shared library point of view, it just does not make sense to have > >> applications linked against a 'combined' library that may have different > >> features built in it. > >> > >> Removing these options, aside from the obvious 'less build config option', > >> it simplifies maintenance of makefiles as we currently have a separated > >> makefile with specific rules just for combined library. > >> > >> It is pretty straight forward to build a single combined archive out of > >> multiple archives, would it be acceptable to have a script to do this? > >> > >> Thanks, > >> Sergio > >> > > +1 > > > > For the static case, its easy to do a post build combination of archives. For > > the shared library case, its equally easy to simply create a linker scripts call > > .so that pulls in all the individual libraries. > > > > Neil > > >