Hi, On Tue, Mar 30, 2021 at 10:29:22PM +0000, MONTET Julien via lttng-dev wrote: > Hello the developpers ! > > On my side, userspace and kernel event are working for both x86_64 and 32bits > on Ubuntu 20.04. > One of my main goals is to use LTTng on an armv7 target (Raspbian 32 bits).
Ok. > > I am using Docker to create the environment and to compile the image (Debian > 9.3). > During the compilation of RCU, I get : > #10 5.868 checking whether the C compiler works... no > #10 5.982 configure: error: in `/tmp/tmp.T2I20x25bo/userspace-rcu-0.12.2': > #10 5.983 configure: error: C compiler cannot create executables I would suggest that you have a look in the config.log file and share with us the complete file, as always use a paste service if possible. > > My question is the following : Can LTTng be used directly on arm ? It can absolutely be used on arm. For example see our portbuild testing matrix here: URCU: https://ci.lttng.org/job/liburcu_master_portbuild/ LTTng-tools: https://ci.lttng.org/job/lttng-tools_master_portbuild/ > https://lttng.org/docs/v2.10/#doc-instrumenting-32-bit-app-on-64-bit-system > I read again the tutorial and it seems we always need a 64-bits platform. On 32bit only platform you are limited to 32bit tracing and all the limitation related to 32bit, if any is applicable to your use case. > > Find below a part of my Dockerfile (that looks like the tuto): > # LTTng RCU - 32 bits > RUN bin/sh -c 'cd $(mktemp -d)' && \ > wget https://lttng.org/files/urcu/userspace-rcu-0.12.2.tar.bz2 && \ > tar -xvf userspace-rcu-0.12.2.tar.bz2 && \ > cd userspace-rcu-0.12.2 && \ > ./configure --libdir=/usr/local/lib32 CFLAGS=-m32 && \ > make && \ > make install && \ > ldconfig > > I tried to run the installation on the docker file of gcc-multilib, > build-essential, wget... but it doesn't work. Our project use standard autotools/make mechanism for cross compilation scenarios: https://www.gnu.org/software/automake/manual/html_node/Cross_002dCompilation.html I am not aware of any problem at this level but after looking around our CI I think we do not do a lot of cross compilation. Still I know that yocto and buildroot use cross-compilation for lttng and its dependencies without any major modification. Still, we will wait for the config.log file before putting this in the: not a lttng problem. Cheers -- Jonathan Rajotte-Julien EfficiOS _______________________________________________ lttng-dev mailing list lttng-dev@lists.lttng.org https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
