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Date:   Tue, 28 Jul 2020 09:13:42 -0300
From:   Arnaldo Carvalho de Melo <acme@kernel.org>
To:     Andrii Nakryiko <andrii.nakryiko@gmail.com>
Cc:     Roman Gushchin <guro@fb.com>, bpf <bpf@vger.kernel.org>,
        Networking <netdev@vger.kernel.org>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Kernel Team <kernel-team@fb.com>,
        open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH bpf-next v2 35/35] perf: don't touch RLIMIT_MEMLOCK
Message-ID: <20200728121342.GD40195@kernel.org>
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Em Mon, Jul 27, 2020 at 11:09:43PM -0700, Andrii Nakryiko escreveu:
> On Mon, Jul 27, 2020 at 12:21 PM Roman Gushchin <guro@fb.com> wrote:
> >
> > Since bpf stopped using memlock rlimit to limit the memory usage,
> > there is no more reason for perf to alter its own limit.
> >
> > Signed-off-by: Roman Gushchin <guro@fb.com>
> > ---
> 
> Cc'd Armaldo, but I'm guessing it's a similar situation that latest
> perf might be running on older kernel and should keep working.

Yes, please leave it as is, the latest perf should continue working with
older kernels, so if there is a way to figure out if the kernel running
is one where BPF doesn't use memlock rlimit for that purpose, then in
those cases we shouldn't use it.

- Arnaldo
 
> >  tools/perf/builtin-trace.c      | 10 ----------
> >  tools/perf/tests/builtin-test.c |  6 ------
> >  tools/perf/util/Build           |  1 -
> >  tools/perf/util/rlimit.c        | 29 -----------------------------
> >  tools/perf/util/rlimit.h        |  6 ------
> >  5 files changed, 52 deletions(-)
> >  delete mode 100644 tools/perf/util/rlimit.c
> >  delete mode 100644 tools/perf/util/rlimit.h
> >
> 
> [...]

-- 

- Arnaldo