Skip to content

Commit

Permalink
[SCSI] aacraid: improve queue balancing
Browse files Browse the repository at this point in the history
The adapter queue is divided up equally to all the arrays to prevent
command starvation to any individual array. On the other hand,
physical targets are only granted a queue depth of one each. The code
prior to this patch used to deal with the incremental discovery of
targets, but the driver knows how many arrays are present prior to the
scan so this knowledge is used to generate a better estimate for the
queue depth.

Remove the capability of 'physical=0' from preventing access to the
class of adapters that have the RAID/SCSI mode of operation since none
of the physicals on the SCSI channel are candidates ever for an array.

As always, the user can override this default queue depth policy by
making the appropriate adjustments utilizing sysfs.

Signed-off-by: Mark Salyzyn <aacraid@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
  • Loading branch information
Salyzyn, Mark authored and James Bottomley committed Jan 23, 2008
1 parent b6ef70f commit b18268f
Showing 1 changed file with 13 additions and 10 deletions.
23 changes: 13 additions & 10 deletions drivers/scsi/aacraid/linit.c
Original file line number Diff line number Diff line change
Expand Up @@ -401,16 +401,14 @@ static int aac_biosparm(struct scsi_device *sdev, struct block_device *bdev,

static int aac_slave_configure(struct scsi_device *sdev)
{
struct aac_dev *aac = (struct aac_dev *)sdev->host->hostdata;
if ((sdev->type == TYPE_DISK) &&
(sdev_channel(sdev) != CONTAINER_CHANNEL)) {
(sdev_channel(sdev) != CONTAINER_CHANNEL) &&
(!aac->raid_scsi_mode || (sdev_channel(sdev) != 2))) {
if (expose_physicals == 0)
return -ENXIO;
if (expose_physicals < 0) {
struct aac_dev *aac =
(struct aac_dev *)sdev->host->hostdata;
if (!aac->raid_scsi_mode || (sdev_channel(sdev) != 2))
sdev->no_uld_attach = 1;
}
if (expose_physicals < 0)
sdev->no_uld_attach = 1;
}
if (sdev->tagged_supported && (sdev->type == TYPE_DISK) &&
(sdev_channel(sdev) == CONTAINER_CHANNEL)) {
Expand All @@ -419,18 +417,23 @@ static int aac_slave_configure(struct scsi_device *sdev)
unsigned num_lsu = 0;
unsigned num_one = 0;
unsigned depth;
unsigned cid;

/*
* Firmware has an individual device recovery time typically
* of 35 seconds, give us a margin.
*/
if (sdev->timeout < (45 * HZ))
sdev->timeout = 45 * HZ;
for (cid = 0; cid < aac->maximum_num_containers; ++cid)
if (aac->fsa_dev[cid].valid)
++num_lsu;
__shost_for_each_device(dev, host) {
if (dev->tagged_supported && (dev->type == TYPE_DISK) &&
(sdev_channel(dev) == CONTAINER_CHANNEL))
++num_lsu;
else
(sdev_channel(dev) == CONTAINER_CHANNEL)) {
if (!aac->fsa_dev[sdev_id(dev)].valid)
++num_lsu;
} else
++num_one;
}
if (num_lsu == 0)
Expand Down

0 comments on commit b18268f

Please sign in to comment.