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From:   Thomas Gleixner <tglx@linutronix.de>
To:     Andy Lutomirski <luto@amacapital.net>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, x86@kernel.org,
        Brian Gerst <brgerst@gmail.com>,
        Juergen Gross <JGross@suse.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Arnd Bergmann <arnd@arndb.de>,
        "Paul E. McKenney" <paulmck@kernel.org>
Subject: Re: [patch 4/8] x86/entry: Move irq tracing on syscall entry to C-code
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References: <87imjofkhx.fsf@nanos.tec.linutronix.de> <AED99B11-8739-450F-932C-EF38C20D44CA@amacapital.net>
Date:   Sun, 01 Mar 2020 16:21:15 +0100
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Andy Lutomirski <luto@amacapital.net> writes:
>> On Mar 1, 2020, at 2:16 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
>> Ok, but for the time being anything before/after CONTEXT_KERNEL is unsafe
>> except trace_hardirq_off/on() as those trace functions do not allow to
>> attach anything AFAICT.
>
> Can you point to whatever makes those particular functions special?  I
> failed to follow the macro maze.

Those are not tracepoints and not going through the macro maze. See
kernel/trace/trace_preemptirq.c

Thanks,

        tglx