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Date: Tue, 1 Aug 2023 20:44:07 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>,
 linux-trace-kernel@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>,
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 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 Tue, 1 Aug 2023 20:40:54 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> Maybe we can add a ftrace_partial_regs(fregs) that returns a
> partially filled pt_regs, and the caller that uses this obviously knows
> its partial (as it's in the name). But this doesn't quite help out arm64
> because unlike x86, struct ftrace_regs does not contain an address
> compatibility with pt_regs fields. It would need to do a copy.
> 
>  ftrace_partial_regs(fregs, &regs) ?

Well, both would be pointers so you wouldn't need the "&", but it was
to stress that it would be copying one to the other.

  void ftrace_partial_regs(const struct ftrace_regs *fregs, struct pt_regs regs);

-- Steve