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From:   John Ogness <john.ogness@linutronix.de>
To:     Peter Geis <pgwipeout@gmail.com>
Cc:     Petr Mladek <pmladek@suse.com>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "open list:ARM/Rockchip SoC..." <linux-rockchip@lists.infradead.org>
Subject: Re: [BUG] Threaded printk breaks early debugging
In-Reply-To: <CAMdYzYr-Wo713Y4qjboTpoK6GcrYfKCfRJAEizwXw6-=dymVzg@mail.gmail.com>
References: <CAMdYzYpF4FNTBPZsEFeWRuEwSies36QM_As8osPWZSr2q-viEA@mail.gmail.com>
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 <CAMdYzYr-Wo713Y4qjboTpoK6GcrYfKCfRJAEizwXw6-=dymVzg@mail.gmail.com>
Date:   Mon, 13 Jun 2022 01:14:50 +0206
Message-ID: <87zgihlbst.fsf@jogness.linutronix.de>
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On 2022-06-10, Peter Geis <pgwipeout@gmail.com> wrote:
> This might be a side effect of the fact that this is on a low powered
> arm64 board. I noticed with threading enabled during large bursts the
> console drops an excessive amount of messages. It's especially
> apparent during the handover from earlycon to the normal console.

I guess you have a very small kernel buffer and are generating unusually
high amounts of messages? Is there a reason you cannot use a larger
buffer?

Or maybe you are generating a constant amount of messages that a serial
port could never keep up with unless it was interfering with the system
in such a way as to slow everything down? This is exactly what printk
should _not_ be used for.

John Ogness