Date:   Mon, 20 Feb 2023 23:16:15 +0300
From:   Alexey Dobriyan <adobriyan@gmail.com>
To:     Frederic Weisbecker <frederic@kernel.org>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Wei Li <liwei391@huawei.com>,
        Mirsad Goran Todorovac <mirsad.todorovac@alu.unizg.hr>,
        Yu Liao <liaoyu15@huawei.com>, Hillf Danton <hdanton@sina.com>,
        Ingo Molnar <mingo@kernel.org>
Subject: Re: [PATCH 7/7] selftests/proc: Remove idle time monotonicity
 assertions
Message-ID: <Y/PVD58nzv8gDhFL@p183>
References: <20230220124129.519477-1-frederic@kernel.org>
 <20230220124129.519477-8-frederic@kernel.org>
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On Mon, Feb 20, 2023 at 01:41:29PM +0100, Frederic Weisbecker wrote:
> Due to broken iowait task counting design (cf: comments above
> get_cpu_idle_time_us() and nr_iowait()), it is not possible to provide
> the guarantee that /proc/stat or /proc/uptime display monotonic idle
> time values.

Those test uptime _and_ idle time? You aren't sacking uptime, right?

>  delete mode 100644 tools/testing/selftests/proc/proc-uptime-001.c
>  delete mode 100644 tools/testing/selftests/proc/proc-uptime-002.c