Add a queue_depth file so that the multipath dynamic queue depth can be looked up from per-path gendisk (scsi_disk) directory.
Signed-off-by: John Garry <[email protected]> --- drivers/scsi/sd.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 52d9bc34bd666..27f64560335a4 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -4232,9 +4232,30 @@ static ssize_t sd_mpath_numa_nodes_show(struct device *dev, } static DEVICE_ATTR(mpath_numa_nodes, 0444, sd_mpath_numa_nodes_show, NULL); +static ssize_t sd_mpath_queue_depth_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct gendisk *gd = dev_to_disk(dev); + struct scsi_disk *sdkp = gd->private_data; + struct scsi_device *sdev = sdkp->device; + struct scsi_mpath_device *scsi_mpath_device = sdev->scsi_mpath_dev; + struct mpath_device *mpath_device = &scsi_mpath_device->mpath_device; + struct sd_mpath_disk *sd_mpath_disk = sdkp->sd_mpath_disk; + struct mpath_disk *mpath_disk = sd_mpath_disk->mpath_disk; + struct mpath_head *mpath_head = mpath_disk->mpath_head; + struct scsi_mpath_head *scsi_mpath_head = mpath_head->drvdata; + + if (!mpath_qd_iopolicy(&scsi_mpath_head->iopolicy)) + return 0; + + return sysfs_emit(buf, "%d\n", atomic_read(&mpath_device->nr_active)); +} +static DEVICE_ATTR(mpath_queue_depth, 0444, sd_mpath_queue_depth_show, NULL); + static struct attribute *sd_mpath_dev_attrs[] = { &dev_attr_mpath_dev.attr, &dev_attr_mpath_numa_nodes.attr, + &dev_attr_mpath_queue_depth.attr, NULL }; -- 2.43.5
