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Date:   Wed, 2 Aug 2023 14:38:45 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc:     Masami Hiramatsu <mhiramat@kernel.org>,
        linux-trace-kernel@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>,
        Martin KaFai Lau <martin.lau@linux.dev>,
        bpf <bpf@vger.kernel.org>, Sven Schnelle <svens@linux.ibm.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Jiri Olsa <jolsa@kernel.org>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Alan Maguire <alan.maguire@oracle.com>,
        Mark Rutland <mark.rutland@arm.com>,
        Florent Revest <revest@chromium.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH v4 3/9] bpf/btf: Add a function to search a member of a
 struct/union
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On Wed, 2 Aug 2023 11:24:12 -0700
Alexei Starovoitov <alexei.starovoitov@gmail.com> wrote:

> This is a non starter.
> bpf progs expect arch dependent 'struct pt_regs *' and we cannot change that.

If the progs are compiled into native code, isn't there optimizations that
could be done? That is, if ftrace_regs is available, and the bpf program is
just using the subset of pt_regs, is it possible that it could be compiled
to use ftrace_regs?

Forgive my ignorance on how BPF programs turn into executables when running
in the kernel.

-- Steve