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authorJan Glauber <jang@linux.vnet.ibm.com>2011-04-20 10:15:33 +0200
committerMartin Schwidefsky <sky@mschwide.boeblingen.de.ibm.com>2011-04-20 10:15:43 +0200
commitbffbbd2df4196a73ffdc16709866dd96eb66aad8 (patch)
treed62c80319e3b63fc352afda230e618d792b9a5fb /drivers/s390
parente4c031b4f2515e9531d71c8aa779799231dbcd0c (diff)
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[S390] qdio: reset error states immediately
The qdio hardware may surpress further interrupts as long as a SBAL is in the error state. That can lead to unnotified data in the SBALs following the error state. To prevent this behaviour change the SBAL[s] in error state immediately to another program owned state so interrupts are again received for further traffic on the device. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390')
-rw-r--r--drivers/s390/cio/qdio_main.c17
1 files changed, 12 insertions, 5 deletions
diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c
index c532ba929ccd..e8f267eb8887 100644
--- a/drivers/s390/cio/qdio_main.c
+++ b/drivers/s390/cio/qdio_main.c
@@ -407,8 +407,11 @@ static inline void account_sbals(struct qdio_q *q, int count)
q->q_stats.nr_sbals[pos]++;
}
-static void announce_buffer_error(struct qdio_q *q, int count)
+static void process_buffer_error(struct qdio_q *q, int count)
{
+ unsigned char state = (q->is_input_q) ? SLSB_P_INPUT_NOT_INIT :
+ SLSB_P_OUTPUT_NOT_INIT;
+
q->qdio_error |= QDIO_ERROR_SLSB_STATE;
/* special handling for no target buffer empty */
@@ -426,6 +429,12 @@ static void announce_buffer_error(struct qdio_q *q, int count)
DBF_ERROR("F14:%2x F15:%2x",
q->sbal[q->first_to_check]->element[14].flags & 0xff,
q->sbal[q->first_to_check]->element[15].flags & 0xff);
+
+ /*
+ * Interrupts may be avoided as long as the error is present
+ * so change the buffer state immediately to avoid starvation.
+ */
+ set_buf_states(q, q->first_to_check, state, count);
}
static inline void inbound_primed(struct qdio_q *q, int count)
@@ -506,8 +515,7 @@ static int get_inbound_buffer_frontier(struct qdio_q *q)
account_sbals(q, count);
break;
case SLSB_P_INPUT_ERROR:
- announce_buffer_error(q, count);
- /* process the buffer, the upper layer will take care of it */
+ process_buffer_error(q, count);
q->first_to_check = add_buf(q->first_to_check, count);
atomic_sub(count, &q->nr_buf_used);
if (q->irq_ptr->perf_stat_enabled)
@@ -677,8 +685,7 @@ static int get_outbound_buffer_frontier(struct qdio_q *q)
account_sbals(q, count);
break;
case SLSB_P_OUTPUT_ERROR:
- announce_buffer_error(q, count);
- /* process the buffer, the upper layer will take care of it */
+ process_buffer_error(q, count);
q->first_to_check = add_buf(q->first_to_check, count);
atomic_sub(count, &q->nr_buf_used);
if (q->irq_ptr->perf_stat_enabled)