Commit e05fe29248 (qla2xxx: Honor FCP_RSP retry delay timer field.)
causes systems to busy-wait for about 3 minutes after boot prior to
detecting SAN disks.

During this wait period one kworker is running full-time
(though /proc/<pid>/stack has no useful data). Another kworker is
waiting for IO to complete during that whole time period.


Looking at drivers/scsi/qla2xxx/qla_os.c, fcport->retry_delay_timestamp
has a special value of 0 though that 0 value forces system to wait when
jiffies is very large value (e.g. 4294952605 - "negative" value when
signed on 32bit systems).

Signed-off-by: Bruno Prémont <bonb...@linux-vserver.org>
---
This fix probably still misses the special case when retry delay wants
jiffies to wrap around to 0...

 drivers/scsi/qla2xxx/qla_os.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index db3dbd9..1df4c66 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -735,7 +735,9 @@ qla2xxx_queuecommand(struct Scsi_Host *host, struct 
scsi_cmnd *cmd)
         * Return target busy if we've received a non-zero retry_delay_timer
         * in a FCP_RSP.
         */
-       if (time_after(jiffies, fcport->retry_delay_timestamp))
+       if (fcport->retry_delay_timestamp == 0) {
+               /* retry delay not set */
+       } else if (time_after(jiffies, fcport->retry_delay_timestamp))
                fcport->retry_delay_timestamp = 0;
        else
                goto qc24_target_busy;
--
2.0.4
--
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to