-----Original Message----- > Date: Wed, 21 Jun 2017 13:36:58 +0300 > From: Ilya Maximets <[email protected]> > To: Jerin Jacob <[email protected]>, Thomas Monjalon > <[email protected]> > CC: Sergio Gonzalez Monroy <[email protected]>, Hemant > Agrawal <[email protected]>, [email protected], Bruce Richardson > <[email protected]>, David Marchand <[email protected]>, > Heetae Ahn <[email protected]>, Yuanhan Liu <[email protected]>, > Jianfeng Tan <[email protected]>, Neil Horman > <[email protected]>, Yulong Pei <[email protected]> > Subject: Re: [PATCH v5 0/2] Balanced allocation of hugepages > User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 > Thunderbird/45.8.0 > > On 21.06.2017 13:29, Jerin Jacob wrote: > > -----Original Message----- > >> Date: Wed, 21 Jun 2017 11:58:12 +0200 > >> From: Thomas Monjalon <[email protected]> > >> To: Jerin Jacob <[email protected]> > >> Cc: Sergio Gonzalez Monroy <[email protected]>, Hemant > >> Agrawal <[email protected]>, Ilya Maximets <[email protected]>, > >> [email protected], Bruce Richardson <[email protected]>, David > >> Marchand <[email protected]>, Heetae Ahn > >> <[email protected]>, Yuanhan Liu <[email protected]>, Jianfeng > >> Tan <[email protected]>, Neil Horman <[email protected]>, Yulong > >> Pei <[email protected]> > >> Subject: Re: [PATCH v5 0/2] Balanced allocation of hugepages > >> > >> 21/06/2017 11:27, Jerin Jacob: > >>> -----Original Message----- > >>>> Date: Wed, 21 Jun 2017 10:49:14 +0200 > >>>> From: Thomas Monjalon <[email protected]> > >>>> To: Jerin Jacob <[email protected]> > >>>> Cc: Sergio Gonzalez Monroy <[email protected]>, Hemant > >>>> Agrawal <[email protected]>, Ilya Maximets > >>>> <[email protected]>, > >>>> [email protected], Bruce Richardson <[email protected]>, David > >>>> Marchand <[email protected]>, Heetae Ahn > >>>> <[email protected]>, Yuanhan Liu <[email protected]>, Jianfeng > >>>> Tan <[email protected]>, Neil Horman <[email protected]>, > >>>> Yulong > >>>> Pei <[email protected]> > >>>> Subject: Re: [PATCH v5 0/2] Balanced allocation of hugepages > >>>> > >>>> 21/06/2017 10:41, Jerin Jacob: > >>>>>>> 1. There are many machines (arm/ppc), which do not support NUMA. > >>>>>>> > >>>>>>> https://wiki.linaro.org/LEG/Engineering/Kernel/NUMA > >>>>>>> > >>>>>> > >>>>>> I did find that link too, last modified 4 years ago. > >>>>>> Despite that, I could not find any ARM references in libnuma sources, > >>>>>> but > >>>>>> Jerin proved that there is support for it. > >>>>>> > >>>>>> http://oss.sgi.com/projects/libnuma/ > >>>>>> https://github.com/numactl/numactl > >>>>> > >>>>> Those Linaro links are very old. ARM64 NUMA supported has been added in > >>>>> 4.7 kernel. > >>>>> I guess we are talking about build time time dependency with libnuma > >>>>> here. > >>>>> Correct? I think, Even with old arm64 kernel(< 4.6), You can build > >>>>> against > >>>>> libnuma if it is present in rootfs. Just that at runtime, it will return > >>>>> NUMA support not available. Correct? > >>>>> > >>>>> How hard is detect the presence of "numaif.h" if existing build system > >>>>> does not > >>>>> support it? If it trivial, we can enable > >>>>> RTE_LIBRTE_EAL_NUMA_AWARE_HUGEPAGES > >>>>> if build environment has "numaif.h". > >>>>> > >>>>> Some example in linux kernel build system: > >>>>> http://lxr.linux.no/linux+v4.10.1/scripts/gcc-goto.sh > >>>> > >>>> I think we should not try to detect numaif.h, because it should be > >>>> an error on platform supporting NUMA. > >>> > >>> I have installed libnuma on a NUMA and non NUMA machine. > >>> Compiled and ran following code on those machine and it could detect > >>> the numa availability. Could you add more details on the "error on > >>> platform supporting NUMA". > >> > >> I was saying that we do not need to detect NUMA. > >> If we are building DPDK for a NUMA architecture and libnuma is not > >> available, then it will be a problem that the user must catch. > >> The easiest way to catch it, is to fail on the include of numaif.h. > > > > libnuma is not really _architecture_ depended. > > > > Ilya Maximets patch disables NUMA support in common arm64 config.I > > think, It is not correct, We should not disable on any archs generic config. > > > > IMO, It should be enabled by default in common config and then we can > > detect the presence of numaif.h, if not available OR a target does not need > > it > > explicitly, proceed with disabling > > RTE_LIBRTE_EAL_NUMA_AWARE_HUGEPAGES. I think, That is more portable. > > Detecting of headers is impossible until dpdk doesn't have dynamic build > configuration system like autotools, CMake or meson. > Right now we just can't do that.
I agree. Unless if we do something like linux kernel does it below http://elixir.free-electrons.com/linux/latest/source/scripts/kconfig/lxdialog/check-lxdialog.sh Either way, I think, you can enable RTE_LIBRTE_EAL_NUMA_AWARE_HUGEPAGES in generic arm64 config and disable on defconfig_arm64-dpaa2-linuxapp-gcc(as Hemant requested) or any sub arch target that does not need in RTE_LIBRTE_EAL_NUMA_AWARE_HUGEPAGES. > > > No strong opinion on "failing the build" vs "printing a warning" in the > > absence of numaif.h
