Em Wed, Jan 03, 2018 at 03:33:07PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Wed, Jan 03, 2018 at 03:27:01PM -0300, Arnaldo Carvalho de Melo escreveu:
> > > Continuing investigation...
> >
> > After applying the fallback patch to allow new tools to work with older
> > kernels:
> >
> > [root@felicio ~]# perf test bpf
> > 39: BPF filter :
> > 39.1: Basic BPF filtering : Ok
> > 39.2: BPF pinning : Ok
> > 39.3: BPF prologue generation : Ok
> > 39.4: BPF relocation checker : Ok
> > [root@felicio ~]# uname -a
> > Linux felicio.ghostprotocols.net 4.13.0-rc7+ #1 SMP Mon Sep 11 13:56:18 -03
> > 2017 x86_64 x86_64 x86_64 GNU/Linux
> > [root@felicio ~]# rpm -q glibc
> > glibc-2.17-157.el7_3.2.x86_64
> > [root@felicio ~]#
> >
> > After applying the patch below I get to, which is what I am trying to
> > fix now:
> >
> > [root@jouet ~]# perf test bpf
> > 39: BPF filter :
> > 39.1: Basic BPF filtering : Ok
> > 39.2: BPF pinning : Ok
> > 39.3: BPF prologue generation : FAILED!
> > 39.4: BPF relocation checker : Skip
> > [root@jouet ~]#
>
> Update the patch to the one at the end of this message to make it work
> with older glibcs, so that we ask for epoll_pwait() and hook into that
> as well().
>
> Now checking why 39.3 fails...
Couldn't reproduce after fixing up some kernel build problems, the patch
below is all I need to have this working with both Fedora 27 and RHEL7,
please take a look and see if it continues to work on your systems,
- Arnaldo
> - Arnaldo
>
> diff --git a/tools/perf/tests/bpf-script-example.c
> b/tools/perf/tests/bpf-script-example.c
> index 268e5f8e4aa2..d1e67e271675 100644
> --- a/tools/perf/tests/bpf-script-example.c
> +++ b/tools/perf/tests/bpf-script-example.c
> @@ -31,7 +31,7 @@ struct bpf_map_def SEC("maps") flip_table = {
> .max_entries = 1,
> };
>
> -SEC("func=SyS_epoll_wait")
> +SEC("func=SyS_epoll_pwait")
> int bpf_func__SyS_epoll_wait(void *ctx)
> {
> int ind =0;
> diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c
> index 0512f1b5bfdb..7c04e2d5b60b 100644
> --- a/tools/perf/tests/bpf.c
> +++ b/tools/perf/tests/bpf.c
> @@ -25,7 +25,7 @@ static int epoll_wait_loop(void)
>
> /* Should fail NR_ITERS times */
> for (i = 0; i < NR_ITERS; i++)
> - epoll_wait(-(i + 1), NULL, 0, 0);
> + epoll_pwait(-(i + 1), NULL, 0, 0, NULL);
> return 0;
> }
>
