On 10/2/18 11:52 PM, Bart Van Assche wrote:
Hello Martin,
During the 2018 edition of LSF/MM there was a session about increasing SCSI
disk probing concurrency. This patch series implements what has been proposed
during that session, namely:
- Make sure that the driver core is aware of asynchronous SCSI LUN probing.
- Avoid unnecessary serialization between sd_probe() and sd_remove() because
this could lead to a deadlock.
Please consider this patch series for kernel v4.20.
Thanks,
Bart.
Bart Van Assche (3):
sd: Rely on the driver core for asynchronous probing
sd: Inline sd_probe_part2()
__device_release_driver(): Do not wait for asynchronous probing
drivers/base/dd.c | 3 --
drivers/scsi/scsi.c | 14 -----
drivers/scsi/scsi_pm.c | 22 +-------
drivers/scsi/scsi_priv.h | 3 --
drivers/scsi/sd.c | 110 ++++++++++++++++-----------------------
5 files changed, 46 insertions(+), 106 deletions(-)
Initially it looks ok-ish.
But I've has so many issues with asynchronous probing that I'd be really
careful here.
However, inlining sd_probe_async() should amount for some contention to
be removed; but I'd rather give it some more testing here.
I've found that testing on large configurations on iSER or SRP tend to
excite the issues.
Can you check against those, too?
I'll see to give it a spin on my test bed.
Cheers,
Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
hare@xxxxxxx +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG Nürnberg)
