mbox series

[RFC,00/15] libiscsi: lock clean ups

Message ID 1606858196-5421-1-git-send-email-michael.christie@oracle.com
Headers show
Series libiscsi: lock clean ups | expand

Message

Mike Christie Dec. 1, 2020, 9:29 p.m. UTC 
The following patches made over Linus's current tree cleanup the
locking in libiscsi so we again, for the main IO path, have the frwd
lock only used in the xmit/queue path and the back lock used in the
completion path and no taskqueuelock. The EH paths still use both
the frwd/back lock though.

These patches are not ready for merging. I have only tested iscsi_tcp.
Also, even though the changes to the offload drivers look like minimal
API use changes, I wanted to try and get some tests done as the changes
affect the main IO and error paths.

Also, I wanted to try and track down any offload maintainers that are
still doing development on their drivers. After this batch of patches
is merged we can go one step further and remove the frwd lock from
queuecommand for at least the iscsi xmit wq based drivers by switching
to some per task locking or lllists. And if we can figure out if the
offload cards manage their own cmdsn window then we could drop the
frwd lock for them too and we could do some optimizatons with the back
lock for them.

Comments

Manish Rangankar Dec. 4, 2020, 12:10 p.m. UTC | #1 
> -----Original Message-----

> From: Mike Christie <michael.christie@oracle.com>

> Sent: Wednesday, December 2, 2020 3:00 AM

> To: subbu.seetharaman@broadcom.com;

> ketan.mukadam@broadcom.com; jitendra.bhivare@broadcom.com;

> lduncan@suse.com; cleech@redhat.com; Nilesh Javali

> <njavali@marvell.com>; Manish Rangankar <mrangankar@marvell.com>;

> GR-QLogic-Storage-Upstream <GR-QLogic-Storage-

> Upstream@marvell.com>; varun@chelsio.com;

> martin.petersen@oracle.com; linux-scsi@vger.kernel.org;

> james.bottomley@hansenpartnership.com

> Subject: [EXT] [RFC PATCH 00/15] libiscsi: lock clean ups

> 

> External Email

> 

> ----------------------------------------------------------------------

> The following patches made over Linus's current tree cleanup the locking in

> libiscsi so we again, for the main IO path, have the frwd lock only used in

> the xmit/queue path and the back lock used in the completion path and no

> taskqueuelock. The EH paths still use both the frwd/back lock though.

> 

> These patches are not ready for merging. I have only tested iscsi_tcp.

> Also, even though the changes to the offload drivers look like minimal API

> use changes, I wanted to try and get some tests done as the changes affect

> the main IO and error paths.

> 

Mike,

We will run the sanity test for qedi and bnx2i.

Thanks,
Manish