On 07/27/2016 08:52 AM, Benjamin Marzinski wrote:
if you look in drivers/md/dm-ioctl.c at do_resume(), device mapper
internally does a suspend when you call resume with a new table loaded.
That's when these suspends are happening.

In the userspace tools, this happens in the DM_DEVICE_RESUME calls after
dm_addmap_reload(), which loads the new table.  These all happen in the
domap() function.

Thanks Ben for chiming in. As far as I can see md->map is only used in the I/O submission path but not in the I/O completion path. So why to suspend and resume I/O before activating the new map? Do you think it would be safe to activate the new map without suspending and resuming I/O?

Thanks,

Bart.
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to