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Subject: Re: [PATCH] blk-mq: Export queue state through
 /sys/kernel/debug/block/*/state
To: Bart Van Assche <Bart.VanAssche@sandisk.com>
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CC: Omar Sandoval <osandov@fb.com>, Hannes Reinecke <hare@suse.de>,
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From: Jens Axboe <axboe@fb.com>
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Date: Wed, 29 Mar 2017 14:31:01 -0600
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On 03/29/2017 02:20 PM, Bart Van Assche wrote:
> Make it possible to check whether or not a block layer queue has
> been stopped. Make it possible to run a blk-mq queue from user
> space.

I like this, I've had run-this-queue wired up as well from sysfs
in the past. Maybe we should push it one further, and also allow
things like running a stopped queue?

Would probably be nicer if the file accepted input like "run" (which
would be your current run-this-queue) and "start" (start stopped
queues).

Then we could also EINVAL writes that we don't grok, instead of
just blindly always running the queue.

-- 
Jens Axboe