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Subject: Re: [PATCH] block/umem: convert tasklet to threaded irq
To:     Christoph Hellwig <hch@infradead.org>,
        Davidlohr Bueso <dave@stgolabs.net>
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        Davidlohr Bueso <dbueso@suse.de>
References: <20210323004856.10206-1-dave@stgolabs.net>
 <20210323172437.GA2463754@infradead.org>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <0d26434e-36e2-58f2-16b4-ef0fa4292c6e@kernel.dk>
Date:   Tue, 23 Mar 2021 11:27:49 -0600
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On 3/23/21 11:24 AM, Christoph Hellwig wrote:
> On Mon, Mar 22, 2021 at 05:48:56PM -0700, Davidlohr Bueso wrote:
>> Tasklets have long been deprecated as being too heavy on the system
>> by running in irq context - and this is not a performance critical
>> path. If a higher priority process wants to run, it must wait for
>> the tasklet to finish before doing so. A more suitable equivalent
>> is to converted to threaded irq instead and deal with the async
>> processing in task context.
> 
> I'm really curious if this driver is still in use at all, or if we
> can drop it.

Me too, I'd be surprised if anyone has used it in... forever. We can
probably drop it - I really dislike making core changes to something
that can't even be tested. Davidlohr, assuming you had no way of
testing this change?

-- 
Jens Axboe