Messages in this thread | | | Date | Thu, 3 Aug 2023 10:59:09 +0200 | From | Peter Zijlstra <> | Subject | Re: [RFC PATCH v6 4/5] sched, tracing: add to report task state in symbolic chars |
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On Thu, Aug 03, 2023 at 04:33:51AM -0400, Ze Gao wrote: > Internal representations of task state are likely to be changed > or ordered, and reporting them to userspace without exporting > them as part of API is basically wrong, which can easily break > a userspace observability tool as kernel evolves. For example, > perf suffers from this and still reports wrong states as of this > writing. > > OTOH, some masqueraded states like TASK_REPORT_IDLE and > TASK_REPORT_MAX are also reported inadvertently, which confuses > things even more and most userspace tools do not even take them > into consideration. > > So add a new variable in company with the old raw value to > report task state in symbolic chars, which are self-explaining > and no further translation is needed. Of course this does not > break any userspace tool. > > Note for PREEMPT_ACTIVE, we introduce 'p' to report it and use > the old conventions for the rest. > > Signed-off-by: Ze Gao <zegao@tencent.com> > Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> > Acked-by: Ian Rogers <irogers@google.com>
I'm not sure you've actually read any of the things I've written. I hate this. Not going to happen.
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