Hi all, hi Bruce, I have an issue to compile 32 bit dpdk (version 20.08) with meson in a 64-bit container. As I can see from meson.build, it deducts the arch from the cc sizeof: dpdk_conf.set('RTE_ARCH_64', cc.sizeof('void *') == 8) The attempts to workaround it and set RTE_ARCH_64 to false gives good values in build/rte_build_config.h: #define RTE_ARCH i686 #undef RTE_ARCH_64 #define RTE_ARCH_I686 1 #define RTE_ARCH_X86 1 #define RTE_CACHE_LINE_SIZE 64 but, nevertheless, dpdk is compiled for 64 bit and not for 32 bit. Before, with make build system, RTE_ARCH_ values defined arch and compilation flags for x86 (like -m32 for i686), but with meson it seems to be more complicated? Is there a way to compile 32 bit dpdk (version 20.08) with meson in a 64-bit environment? Kind regards, Renata
On Tue, Oct 13, 2020 at 03:54:13PM +0000, Renata Saiakhova wrote:
> Hi all, hi Bruce,
>
> I have an issue to compile 32 bit dpdk (version 20.08) with meson in a
> 64-bit container.
>
> As I can see from meson.build, it deducts the arch from the cc sizeof:
>
> dpdk_conf.set('RTE_ARCH_64', cc.sizeof('void *') == 8)
>
> The attempts to workaround it and set RTE_ARCH_64 to false gives good
> values in build/rte_build_config.h:
>
> #define RTE_ARCH i686
> #undef RTE_ARCH_64
> #define RTE_ARCH_I686 1
> #define RTE_ARCH_X86 1
> #define RTE_CACHE_LINE_SIZE 64
> but, nevertheless, dpdk is compiled for 64 bit and not for 32 bit.
> Before, with make build system, RTE_ARCH_ values defined arch and
> compilation flags for x86 (like -m32 for i686), but with meson it seems
> to be more complicated?
> Is there a way to compile 32 bit dpdk (version 20.08) with meson in a
> 64-bit environment?
> Kind regards,
> Renata
Hi Renata,
there are two ways to do this - firstly one can create and use a
cross-file, but secondly, and easier, one just needs to tell the compiler
to create 32-bit binaries using the -m32 flag. In this second case, the
only additional complication is that you need to ensure that pkg-config
looks for the relevant .pc files in a 32-bit lib directory rather than a
64-bit one.
Based on that, on my Ubuntu system, the following commands will work to do a
32-bit build of DPDK:
$ PKG_CONFIG_LIBDIR=/usr/lib/i386-linux-gnu/pkgconfig/ meson -Dc_args='-m32' \
-Dc_link_args='-m32' build-32bit
$ ninja -C build-32bit
Checking the resulting binary:
$ file build-32bit/app/dpdk-testpmd
build-32bit/app/dpdk-testpmd: ELF 32-bit LSB shared object, Intel 80386, \
version 1 (SYSV), dynamically linked, ...
Depending on your Linux distribution, the pkg-config libdir you need to
specify may be different, e.g. /usr/lib32/pkgconfig, perhaps. Note also
that it's the "_LIBDIR" variable rather than "PKG_CONFIG_PATH" that must
be set, since the latter just appends to the search paths rather than
replacing them with 32-bit versions.
Regards,
/Bruce
Hi Bruce,
thanks, the second variant is indeed easy! Is there any advantage to create a cross-file instead of just passing an option to compiler and linker and specifying pkg-config libdir? or would it be more "canonical"?
Kind regards,
Renata
________________________________
From: Bruce Richardson <bruce.richardson@intel.com>
Sent: Tuesday, October 13, 2020 6:04 PM
To: Renata Saiakhova <renata.saiakhova@ekinops.com>
Cc: users@dpdk.org <users@dpdk.org>
Subject: Re: Compiling 32-bit dpdk with meson in 64-bit container
On Tue, Oct 13, 2020 at 03:54:13PM +0000, Renata Saiakhova wrote:
> Hi all, hi Bruce,
>
> I have an issue to compile 32 bit dpdk (version 20.08) with meson in a
> 64-bit container.
>
> As I can see from meson.build, it deducts the arch from the cc sizeof:
>
> dpdk_conf.set('RTE_ARCH_64', cc.sizeof('void *') == 8)
>
> The attempts to workaround it and set RTE_ARCH_64 to false gives good
> values in build/rte_build_config.h:
>
> #define RTE_ARCH i686
> #undef RTE_ARCH_64
> #define RTE_ARCH_I686 1
> #define RTE_ARCH_X86 1
> #define RTE_CACHE_LINE_SIZE 64
> but, nevertheless, dpdk is compiled for 64 bit and not for 32 bit.
> Before, with make build system, RTE_ARCH_ values defined arch and
> compilation flags for x86 (like -m32 for i686), but with meson it seems
> to be more complicated?
> Is there a way to compile 32 bit dpdk (version 20.08) with meson in a
> 64-bit environment?
> Kind regards,
> Renata
Hi Renata,
there are two ways to do this - firstly one can create and use a
cross-file, but secondly, and easier, one just needs to tell the compiler
to create 32-bit binaries using the -m32 flag. In this second case, the
only additional complication is that you need to ensure that pkg-config
looks for the relevant .pc files in a 32-bit lib directory rather than a
64-bit one.
Based on that, on my Ubuntu system, the following commands will work to do a
32-bit build of DPDK:
$ PKG_CONFIG_LIBDIR=/usr/lib/i386-linux-gnu/pkgconfig/ meson -Dc_args='-m32' \
-Dc_link_args='-m32' build-32bit
$ ninja -C build-32bit
Checking the resulting binary:
$ file build-32bit/app/dpdk-testpmd
build-32bit/app/dpdk-testpmd: ELF 32-bit LSB shared object, Intel 80386, \
version 1 (SYSV), dynamically linked, ...
Depending on your Linux distribution, the pkg-config libdir you need to
specify may be different, e.g. /usr/lib32/pkgconfig, perhaps. Note also
that it's the "_LIBDIR" variable rather than "PKG_CONFIG_PATH" that must
be set, since the latter just appends to the search paths rather than
replacing them with 32-bit versions.
Regards,
/Bruce
On Tue, Oct 13, 2020 at 04:28:16PM +0000, Renata Saiakhova wrote: > Hi Bruce, > > thanks, the second variant is indeed easy! Is there any advantage to > create a cross-file instead of just passing an option to compiler and > linker and specifying pkg-config libdir? or would it be more > "canonical"? > The cross-file might give you more flexibility in setting additional options and the like, but I believe just setting the '-m32' flag works fine. /Bruce > __________________________________________________________________ > > From: Bruce Richardson <bruce.richardson@intel.com> > Sent: Tuesday, October 13, 2020 6:04 PM > To: Renata Saiakhova <renata.saiakhova@ekinops.com> > Cc: users@dpdk.org <users@dpdk.org> > Subject: Re: Compiling 32-bit dpdk with meson in 64-bit container > > On Tue, Oct 13, 2020 at 03:54:13PM +0000, Renata Saiakhova wrote: > > Hi all, hi Bruce, > > > > I have an issue to compile 32 bit dpdk (version 20.08) with meson > in a > > 64-bit container. > > > > As I can see from meson.build, it deducts the arch from the cc > sizeof: > > > > dpdk_conf.set('RTE_ARCH_64', cc.sizeof('void *') == 8) > > > > The attempts to workaround it and set RTE_ARCH_64 to false gives > good > > values in build/rte_build_config.h: > > > > #define RTE_ARCH i686 > > #undef RTE_ARCH_64 > > #define RTE_ARCH_I686 1 > > #define RTE_ARCH_X86 1 > > #define RTE_CACHE_LINE_SIZE 64 > > but, nevertheless, dpdk is compiled for 64 bit and not for 32 bit. > > Before, with make build system, RTE_ARCH_ values defined arch and > > compilation flags for x86 (like -m32 for i686), but with meson it > seems > > to be more complicated? > > Is there a way to compile 32 bit dpdk (version 20.08) with meson > in a > > 64-bit environment? > > Kind regards, > > Renata > Hi Renata, > there are two ways to do this - firstly one can create and use a > cross-file, but secondly, and easier, one just needs to tell the > compiler > to create 32-bit binaries using the -m32 flag. In this second case, the > only additional complication is that you need to ensure that pkg-config > looks for the relevant .pc files in a 32-bit lib directory rather than > a > 64-bit one. > Based on that, on my Ubuntu system, the following commands will work to > do a > 32-bit build of DPDK: > $ PKG_CONFIG_LIBDIR=/usr/lib/i386-linux-gnu/pkgconfig/ meson > -Dc_args='-m32' \ > -Dc_link_args='-m32' build-32bit > $ ninja -C build-32bit > Checking the resulting binary: > $ file build-32bit/app/dpdk-testpmd > build-32bit/app/dpdk-testpmd: ELF 32-bit LSB shared object, Intel > 80386, \ > version 1 (SYSV), dynamically linked, ... > Depending on your Linux distribution, the pkg-config libdir you need to > specify may be different, e.g. /usr/lib32/pkgconfig, perhaps. Note also > that it's the "_LIBDIR" variable rather than "PKG_CONFIG_PATH" that > must > be set, since the latter just appends to the search paths rather than > replacing them with 32-bit versions. > Regards, > /Bruce