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Date:   Thu, 6 Oct 2022 12:29:22 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Florent Revest <revest@chromium.org>
Cc:     Xu Kuohai <xukuohai@huawei.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Xu Kuohai <xukuohai@huaweicloud.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
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        Ingo Molnar <mingo@redhat.com>,
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        Alexei Starovoitov <ast@kernel.org>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
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Subject: Re: [PATCH bpf-next v2 0/4] Add ftrace direct call for arm64
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On Thu, 6 Oct 2022 18:19:12 +0200
Florent Revest <revest@chromium.org> wrote:

> Sure, we can give this a try, I'll work on a macro that generates the
> 7 callbacks and we can check how much that helps. My belief right now
> is that ftrace's iteration over all ops on arm64 is where we lose most
> time but now that we have numbers it's pretty easy to check hypothesis
> :)

Ah, I forgot that's what Mark's code is doing. But yes, that needs to be
fixed first. I forget that arm64 doesn't have the dedicated trampolines yet.

So, let's hold off until that is complete.

-- Steve