On Wed, Apr 03, 2019 at 11:14:58PM +0800, Ye Xiaolong wrote: > On 04/03, Luca Boccassi wrote: > >On Wed, 2019-04-03 at 22:43 +0800, Ye Xiaolong wrote: > >> On 04/03, Luca Boccassi wrote: > >> [snip] > >> > > Got it. > >> > > > >> > > In above steps, 'libbpf' also build from kernel source tree, will > >> > > it > >> > > be problem > >> > > in you builds to not have it build from source? > >> > > > >> > > If not, taking into account that xsk.h also will be fixed, only > >> > > 'tools/include/asm/barrier.h' remains the problem, and it looks > >> > > like > >> > > it can be > >> > > solved, please check above. > >> > > >> > libbpf is already packaged separately in Debian and I think other > >> > distros will follow soon, so it's all good for me once the barrier > >> > issue is solved. > >> > > >> > https://packages.debian.org/buster/libbpf-dev > >> > > >> > > >> > From the makefile's perspective it should not matter where it comes > >> > from - the headers should be expected to be in /usr/include and the > >> > library in /usr/lib* - and pkg-config can help with that if > >> > available. > >> > And if a user wants to use a custom path, then it's no different > >> > than > >> > any of the other dependencies on other external libraries > >> > >> From tools/lib/bpf/Makefile, after make install_lib and make > >> install_headers, > >> the headers and library would be put in /usr/local/include/bpf and > >> /usr/local/lib*, > >> Is it ok? > > > >Yes certainly that's fine, that's expected for local installations, and > >users can specify a prefix with the upstream's makefile if they want to > >install somewhere else. > > In my local test, if I run `make install_lib` to install the libbpf.so to > /usr/local/lib64, `-lbpf` specified in af_xdp pmd still fails to find the > library, > the build would end up with a lot of undefined references which are defined > in libbpf. > It means during dpdk compilation, it won't search libraries in > /usr/local/lib*, right? > > Install the libbpf to /usr/lib64 via `make install_lib prefix=/usr` doesn't > have > this issue, so shall I just document it in af_xdp.rst or there is other proper > way to do it? > At a guess I'd say you are using Fedora Linux, right? Fedora is unusual in that it doesn't by default add /usr/local to the library and header search paths so you need to explicitly add them to your environment. Other distros should work fine for this.
/Bruce
