> On Sep 3, 2020, at 1:20 AM, Juraj Linkeš <juraj.lin...@pantheon.tech> wrote: > > > >> -----Original Message----- >> From: dev <dev-boun...@dpdk.org> On Behalf Of Dharmik Thakkar >> Sent: Wednesday, August 26, 2020 6:56 AM >> To: Jerin Jacob <jerinjac...@gmail.com> >> Cc: tho...@monjalon.net; dpdk-dev <dev@dpdk.org>; nd <n...@arm.com> >> Subject: Re: [dpdk-dev] [PATCH 2/2] build: find max lcore programmatically >> >> >> >>> On Aug 25, 2020, at 11:47 PM, Jerin Jacob <jerinjac...@gmail.com> wrote: >>> >>> On Wed, Aug 26, 2020 at 2:44 AM Dharmik Thakkar >> <dharmik.thak...@arm.com> wrote: >>>> >>>> For Arm, RTE_MAX_LCORE is hard-coded into the config. It leads to >>>> incorrect RTE_MAX_LCORE when machines have same Implemener and part >>>> number but different number of CPUs. >>>> For x86, RTE_MAX_LCORE is always set to 128 (using the value set in >>>> meson_options.txt) >>>> >>>> Use python script to find max lcore when using native build to >>>> correctly set RTE_MAX_LCORE. >>> >>> We may need to build on the native arm64 machine and use it on another >>> arm64 machine(Just like x86). >>> So I think, at least for default config(which will be used by >>> distribution) to support max >>> lcores as fixed. I am not sure this patch changes those aspects or >>> not? Please check. >> >> This patch does *not* affect ‘default’ build type and cross-compilation. >> >>> >>>> >>>> Signed-off-by: Dharmik Thakkar <dharmik.thak...@arm.com> >>>> Reviewed-by: Ruifeng Wang <ruifeng.w...@arm.com> >>>> --- >>>> config/get_max_lcores.py | 13 +++++++++++++ >>>> config/meson.build | 13 ++++++++++++- >>>> 2 files changed, 25 insertions(+), 1 deletion(-) create mode 100755 >>>> config/get_max_lcores.py >>>> >>>> diff --git a/config/get_max_lcores.py b/config/get_max_lcores.py new >>>> file mode 100755 index 000000000000..ebf1c7efdadd >>>> --- /dev/null >>>> +++ b/config/get_max_lcores.py >>>> @@ -0,0 +1,13 @@ >>>> +#!/usr/bin/python3 >>>> +# SPDX-License-Identifier: BSD-3-Clause # Copyright(c) 2020 Arm >>>> +Limited >>>> + >>>> +import os >>>> + >>>> +max_lcores = [] >>>> + >>>> +nCPU = os.cpu_count() >>>> + >>>> +max_lcores.append(str(nCPU & 0xFFF)) # Number of CPUs >>>> + >>>> +print(' '.join(max_lcores)) >>>> diff --git a/config/meson.build b/config/meson.build index >>>> 6996e5cbeaa5..80c05bc15d2f 100644 >>>> --- a/config/meson.build >>>> +++ b/config/meson.build >>>> @@ -237,11 +237,22 @@ else # for 32-bit we need smaller reserved memory >> areas >>>> dpdk_conf.set('RTE_MAX_MEM_MB', 2048) endif >>>> >>>> - >>>> compile_time_cpuflags = [] >>>> subdir(arch_subdir) >>>> dpdk_conf.set('RTE_COMPILE_TIME_CPUFLAGS', >>>> ','.join(compile_time_cpuflags)) >>>> >>>> +# set max lcores >>>> +if machine != 'default' and not meson.is_cross_build() >>>> + # The script returns max lcores >>>> + params = files('get_max_lcores.py') >>>> + cmd_out = run_command(params) > > Have you considered running just a shell command, such as "nproc --all"?
Shell command based solution such as “nproc —all” is not OS-agnostic, it doesn’t work on Windows. > >>>> + if cmd_out.returncode() == 0 >>>> + cmd_lcore = cmd_out.stdout().to_lower().strip().split(' ') >>>> + endif >>>> + max_lcore = cmd_lcore[0].to_int() >>>> + dpdk_conf.set('RTE_MAX_LCORE', max_lcore) endif >>>> + >>>> # set the install path for the drivers >>>> dpdk_conf.set_quoted('RTE_EAL_PMD_PATH', eal_pmd_path) >>>> >>>> -- >>>> 2.17.1