scsi: scsi_debug: Simplify request tag decoding

Since commit 64d513ac31 ("scsi: use host wide tags by default") all
SCSI requests have a tag, whether or not scsi-mq is enabled.

Additionally, it is safe to use blk_mq_unique_tag() and
blk_mq_unique_tag_to_hwq() for legacy SCSI queues. Since this means that
the sdebug_mq_active variable is superfluous, remove it.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Bart Van Assche 2018-01-26 08:52:19 -08:00 committed by Martin K. Petersen
parent 34e81f7a72
commit 458df78b1c

View file

@ -649,7 +649,6 @@ static bool sdebug_any_injecting_opt;
static bool sdebug_verbose;
static bool have_dif_prot;
static bool sdebug_statistics = DEF_STATISTICS;
static bool sdebug_mq_active;
static unsigned int sdebug_store_sectors;
static sector_t sdebug_capacity; /* in sectors */
@ -3727,20 +3726,13 @@ static int resp_xdwriteread_10(struct scsi_cmnd *scp,
static struct sdebug_queue *get_queue(struct scsi_cmnd *cmnd)
{
struct sdebug_queue *sqp = sdebug_q_arr;
u32 tag = blk_mq_unique_tag(cmnd->request);
u16 hwq = blk_mq_unique_tag_to_hwq(tag);
if (sdebug_mq_active) {
u32 tag = blk_mq_unique_tag(cmnd->request);
u16 hwq = blk_mq_unique_tag_to_hwq(tag);
if (unlikely(hwq >= submit_queues)) {
pr_warn("Unexpected hwq=%d, apply modulo\n", hwq);
hwq %= submit_queues;
}
pr_debug("tag=%u, hwq=%d\n", tag, hwq);
return sqp + hwq;
} else
return sqp;
pr_debug("tag=%#x, hwq=%d\n", tag, hwq);
if (WARN_ON_ONCE(hwq >= submit_queues))
hwq = 0;
return sdebug_q_arr + hwq;
}
/* Queued (deferred) command completions converge here. */
@ -4587,9 +4579,8 @@ static int scsi_debug_show_info(struct seq_file *m, struct Scsi_Host *host)
num_host_resets);
seq_printf(m, "dix_reads=%d, dix_writes=%d, dif_errors=%d\n",
dix_reads, dix_writes, dif_errors);
seq_printf(m, "usec_in_jiffy=%lu, %s=%d, mq_active=%d\n",
TICK_NSEC / 1000, "statistics", sdebug_statistics,
sdebug_mq_active);
seq_printf(m, "usec_in_jiffy=%lu, statistics=%d\n", TICK_NSEC / 1000,
sdebug_statistics);
seq_printf(m, "cmnd_count=%d, completions=%d, %s=%d, a_tsf=%d\n",
atomic_read(&sdebug_cmnd_count),
atomic_read(&sdebug_completions),
@ -5612,13 +5603,8 @@ static int scsi_debug_queuecommand(struct Scsi_Host *shost,
n += scnprintf(b + n, sb - n, "%02x ",
(u32)cmd[k]);
}
if (sdebug_mq_active)
sdev_printk(KERN_INFO, sdp, "%s: tag=%u, cmd %s\n",
my_name, blk_mq_unique_tag(scp->request),
b);
else
sdev_printk(KERN_INFO, sdp, "%s: cmd %s\n", my_name,
b);
sdev_printk(KERN_INFO, sdp, "%s: tag=%#x, cmd %s\n", my_name,
blk_mq_unique_tag(scp->request), b);
}
if (fake_host_busy(scp))
return SCSI_MLQUEUE_HOST_BUSY;
@ -5782,8 +5768,7 @@ static int sdebug_driver_probe(struct device * dev)
}
/* Decide whether to tell scsi subsystem that we want mq */
/* Following should give the same answer for each host */
sdebug_mq_active = shost_use_blk_mq(hpnt) && (submit_queues > 1);
if (sdebug_mq_active)
if (shost_use_blk_mq(hpnt))
hpnt->nr_hw_queues = submit_queues;
sdbg_host->shost = hpnt;