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From:   Alexei Starovoitov <alexei.starovoitov@gmail.com>
Date:   Mon, 8 Jul 2019 16:16:25 -0700
Message-ID: <CAADnVQ+imsK-reGBiSzY02e+KdyGYZxm1su7T1bWvti=YmSV-Q@mail.gmail.com>
Subject: Re: [tip:x86/urgent] bpf: Fix ORC unwinding in non-JIT BPF code
To:     Josh Poimboeuf <jpoimboe@redhat.com>
Cc:     Ingo Molnar <mingo@kernel.org>, Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>, Song Liu <songliubraving@fb.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Steven Rostedt <rostedt@goodmis.org>,
        Kairui Song <kasong@redhat.com>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Alexei Starovoitov <ast@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-tip-commits@vger.kernel.org
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On Mon, Jul 8, 2019 at 4:02 PM Josh Poimboeuf <jpoimboe@redhat.com> wrote:
> > >
> > > modprobe test_bpf
> > > selftests/bpf/test_progs
> > > both print runtime.
> > > Some of test_progs have high run-to-run variations though.
> >
> > Thanks, I'll give it a shot.
>
> I modprobed test_bpf with JIT disabled.
>
> Before: 2.493018s
> After:  2.523572s
>
> So it looks like it's either no change, or slightly slower.

total time is hard to compare.
Could you compare few tests?
like two that are called "tcpdump *"

I think small regression is ok.
Folks that care about performance should be using JIT.