Commit 6cbed91a authored Jul 17, 2007 by Frank Pavlic Committed by Martin Schwidefsky Jul 17, 2007

[S390] qdio: output queue stall on FCP and network devices



When running QIOASSIST enabled qdio devices in a z/VM environment
the output queue for such devices stall in heavy workload situations.
When SQBS and EQBS instructions returns CCQ=96 qdio does not reissue
the instruction again with the register settings done by millicode
but processed the returned qdio buffer. This is wrong. qdio has to
reissue the instruction once again on CCQ=96, as we already do it
for CCQ=97.

Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

parent 92d154b6

drivers/s390/cio/qdio.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -166,9 +166,9 @@ qdio_check_ccq(struct qdio_q *q, unsigned int ccq)
		{
		char dbf_text[15];

		if (ccq == 0 \|\| ccq == 32 \|\| ccq == 96)
		if (ccq == 0 \|\| ccq == 32)
		return 0;
		if (ccq == 97)
		if (ccq == 96 \|\| ccq == 97)
		return 1;
		/notify devices immediately/
		sprintf(dbf_text,"%d", ccq);

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