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authorJan Glauber <jang@linux.vnet.ibm.com>2011-01-05 12:47:50 +0100
committerMartin Schwidefsky <sky@mschwide.boeblingen.de.ibm.com>2011-01-05 12:47:28 +0100
commit3d6c76ff32bb9b2ebf6e859855d315eb42e3df50 (patch)
tree3a69d4f3023e75fee0bc55ba38ca7a54a8e4760c /drivers/s390/cio/qdio_main.c
parent4f325184f2d4c1f2258873b2a333005dc4dfcbc0 (diff)
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[S390] qdio: outbound tasklet scan threshold
Introduce a scan treshold for the qdio outbound queues. By setting the threshold the driver can tell qdio after how much used SBALs qdio should schedule the outbound tasklet that scans the queue for finished SBALs. The threshold is specific by the drivers because a Hipersockets device is much faster in utilizing outbound buffers than a ZFCP or OSA device. The default values after how many used SBALs the tasklet should run are: OSA: > 31 SBALs Hipersockets: > 7 SBALs zfcp: > 55 SBALs Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/cio/qdio_main.c')
-rw-r--r--drivers/s390/cio/qdio_main.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c
index 6621de94f3ad..4c0109900c74 100644
--- a/drivers/s390/cio/qdio_main.c
+++ b/drivers/s390/cio/qdio_main.c
@@ -1492,7 +1492,13 @@ static int handle_outbound(struct qdio_q *q, unsigned int callflags,
qperf_inc(q, fast_requeue);
out:
- tasklet_schedule(&q->tasklet);
+ /* in case of SIGA errors we must process the error immediately */
+ if (used >= q->u.out.scan_threshold || rc)
+ tasklet_schedule(&q->tasklet);
+ else
+ /* free the SBALs in case of no further traffic */
+ if (!timer_pending(&q->u.out.timer))
+ mod_timer(&q->u.out.timer, jiffies + HZ);
return rc;
}