Re: [PATCH RFC v2 12/24] hpsa: use reserved commands

From: Hannes Reinecke
Date: Tue Mar 17 2020 - 05:48:54 EST


On 3/17/20 10:38 AM, John Garry wrote:
On 11/03/2020 08:10, Ming Lei wrote:
ands(struct ctlr_info *h)
@@ -5803,6 +5803,7 @@ static int hpsa_scsi_host_alloc(struct ctlr_info *h)
ÂÂÂÂÂ sh->max_lun = HPSA_MAX_LUN;
ÂÂÂÂÂ sh->max_id = HPSA_MAX_LUN;
ÂÂÂÂÂ sh->can_queue = h->nr_cmds - HPSA_NRESERVED_CMDS;
+ÂÂÂ sh->nr_reserved_cmds = HPSA_NRESERVED_CMDS;
Now .nr_reserved_cmds has been passed to blk-mq, you need to increase
sh->can_queue to h->nr_cmds, because .can_queue is the whole queue depth
(include the part of reserved tags), otherwise, IO tags will be
decreased.


Sounds correct.

I will have having a look at the patchset; I thought I did a patch to modify .can_queue so that it would cover only the usable tags, not the reserved ones.

Cheers,

Hannes
--
Dr. Hannes Reinecke Teamlead Storage & Networking
hare@xxxxxxx +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 NÃrnberg
HRB 36809 (AG NÃrnberg), GeschÃftsfÃhrer: Felix ImendÃrffer