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Date:   Tue, 1 Aug 2023 13:46:50 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Ze Gao <zegao2021@gmail.com>
Cc:     Adrian Hunter <adrian.hunter@intel.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Ian Rogers <irogers@google.com>,
        Ingo Molnar <mingo@redhat.com>, Jiri Olsa <jolsa@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
        linux-trace-kernel@vger.kernel.org,
        linux-trace-devel@vger.kernel.org, Ze Gao <zegao@tencent.com>
Subject: Re: [RFC PATCH v3 4/6] sched, tracing: reorganize fields of switch
 event struct
Message-ID: <20230801114650.GE79828@hirez.programming.kicks-ass.net>
References: <20230801090124.8050-1-zegao@tencent.com>
 <20230801090124.8050-5-zegao@tencent.com>
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On Tue, Aug 01, 2023 at 05:01:22PM +0800, Ze Gao wrote:
> Report priorities in 'short' and prev_state in 'int' to save
> some buffer space. And also reorder the fields so that we take
> struct alignment into consideration to make the record compact.
> 
> Suggested-by: Steven Rostedt (Google) <rostedt@goodmis.org>

I don't see a single line describing the effort you've done to audit
consumers of this tracepoint.

*IF* you're wanting to break this tracepoint ABI, because seriously
that's what it is, then you get to invest the time and effort to audit
the users.