On 13/03/2015 13:16, Kavanagh, Mark B wrote: > >> -----Original Message----- >> From: Gonzalez Monroy, Sergio >> Sent: Friday, March 13, 2015 11:49 AM >> To: Kavanagh, Mark B >> Cc: dev at dpdk.org >> Subject: Re: [dpdk-dev] [PATCH v2 1/4] mk: Remove combined library and >> related options >> >> 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. >> > For OVS, we don't build DPDK as a set of shared libraries, but rather an > individual static library, due to the performance penalties inherent in using > shared libraries. > >> 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? >> > This seems a bit 'hacky' to me and I'm not sure that it would be amenable to > the OVS maintainers. Unless I'm overlooking something here, I'd prefer to > maintain the status quo. This may be a case of personal opinions, but I don't think there is anything 'hacky' about it. Straight forward extract objects from archive, then archive them into a single library.
Currently to create a combined library we just copy all objects into one directory, then create the combined archive. After the patch, the script just needs to extract all objects from individual libraries into a directory and archive them all. In my opinion, one little exra step, same result plus we get less build config options, simplify lib building by removing the 'combined' lib path. >> Thanks, >> Sergio
