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From: Christoph Hellwig <hch@lst.de>
To: Bjorn Helgaas <helgaas@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, Jeremy Allison <jra@samba.org>,
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Subject: Re: [PATCH 1/4] driver core: Support two-pass driver shutdown
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On Fri, Jan 05, 2024 at 12:15:17PM -0600, Bjorn Helgaas wrote:
> This is a bit of hand waving because I'm not a workqueue expert, but
> it seems like basically the same amount of overhead without having to
> add .shutdown_wait() to the bus_type and the pci_driver.

It spawns a new work for the busy wait for the shutdown.  That's not a
very efficient programming model.