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Date:   Fri, 22 Jul 2022 14:33:44 -0400
From:   Mike Snitzer <snitzer@redhat.com>
To:     Bart Van Assche <bvanassche@acm.org>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Nathan Huckleberry <nhuck@google.com>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        Mike Snitzer <snitzer@kernel.org>,
        linux-kernel@vger.kernel.org, Eric Biggers <ebiggers@kernel.org>,
        dm-devel@redhat.com, Sami Tolvanen <samitolvanen@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Alasdair Kergon <agk@redhat.com>
Subject: Re: [PATCH 0/3] dm-verity: optionally use tasklets in dm-verity
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 <cabd732a-9942-3ece-8141-c0bc6378faca@acm.org>
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On Fri, Jul 22 2022 at  2:12P -0400,
Bart Van Assche <bvanassche@acm.org> wrote:

> On 7/22/22 09:41, Christoph Hellwig wrote:
> > We've been tying to kill off task lets for about 15 years.  I don't
> > think adding new users will make you a whole lot of friends..
> 
> +1 for not using tasklets. At least in Android the real-time thread
> scheduling latency is important. Tasklets are not visible to the scheduler
> and hence cause latency spikes for real-time threads. These latency spikes
> can be observed by users, e.g. if the real-time thread is involved in audio
> playback.

OK, then android wouldn't set the _optional_ "try_verify_in_tasklet"

Mike