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Date:   Mon, 8 Jun 2020 09:42:54 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Jens Axboe <axboe@kernel.dk>, frederic@kernel.org,
        linux-kernel@vger.kernel.org, linux-block@vger.kernel.org
Subject: Re: blk-softirq vs smp_call_function_single_async()
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On Mon, Jun 08, 2020 at 06:40:09PM +0200, Peter Zijlstra wrote:
> There isn't one, it was meant to be used with static allocations.
> 
> Frederic proposed changing all these to irq_work, and I think I'll go do
> that. First dinner though.

The irq_work API looks reasonable.  What are the tradeoffs for
smp_call_single_async vs irq_work?