Re: [PATCH] scsi-misc-2.5 user per-device spare command

Christoph Hellwig
2003-04-25T16:38:29Z

On Fri, Apr 25, 2003 at 09:37:18AM -0700, Patrick Mansfield wrote:
> So we are guaranteed to be able to have at least one IO in flight for all
> devices. With a per-host spare, some device(s) might have to wait
> (generally polling based on an interval dependent on whatever blk_plug_device
> gives us) for a command to become available, and it is not clear what the
> IO behaviour - especially for swap - will be in such cases.

Ok.

> The sdev->sdev_lock (i.e. queue_lock) protects access to sdev->spare_cmd.

Then you'll sleep with the lock help for !GFP_ATOMIC allocations. That's
bad.