s390/qdio: rework BUG's and WARN_ON's
Remove or replace BUG/BUG_ON where possible and convert WARN_ON
to WARN_ON_ONCE if they can occur freqeuently as pointed out by:
https://lkml.org/lkml/2012/9/27/461
Checks have been removed if:
- the error condition leads to a hardware error which gets logged
and in most cases stops the device
- the error condition is a null pointer access
- the error condition is just pointless or already handled at
another location
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c
index e06fa03..1671d34 100644
--- a/drivers/s390/cio/qdio_main.c
+++ b/drivers/s390/cio/qdio_main.c
@@ -129,7 +129,6 @@
int rc, tmp_count = count, tmp_start = start, nr = q->nr, retried = 0;
unsigned int ccq = 0;
- BUG_ON(!q->irq_ptr->sch_token);
qperf_inc(q, eqbs);
if (!q->is_input_q)
@@ -147,7 +146,6 @@
}
if (rc == 2) {
- BUG_ON(tmp_count == count);
qperf_inc(q, eqbs_partial);
DBF_DEV_EVENT(DBF_WARN, q->irq_ptr, "EQBS part:%02x",
tmp_count);
@@ -189,8 +187,6 @@
if (!count)
return 0;
-
- BUG_ON(!q->irq_ptr->sch_token);
qperf_inc(q, sqbs);
if (!q->is_input_q)
@@ -199,7 +195,7 @@
ccq = do_sqbs(q->irq_ptr->sch_token, state, nr, &tmp_start, &tmp_count);
rc = qdio_check_ccq(q, ccq);
if (!rc) {
- WARN_ON(tmp_count);
+ WARN_ON_ONCE(tmp_count);
return count - tmp_count;
}
@@ -224,9 +220,6 @@
unsigned char __state = 0;
int i;
- BUG_ON(bufnr > QDIO_MAX_BUFFERS_MASK);
- BUG_ON(count > QDIO_MAX_BUFFERS_PER_Q);
-
if (is_qebsm(q))
return qdio_do_eqbs(q, state, bufnr, count, auto_ack);
@@ -258,9 +251,6 @@
{
int i;
- BUG_ON(bufnr > QDIO_MAX_BUFFERS_MASK);
- BUG_ON(count > QDIO_MAX_BUFFERS_PER_Q);
-
if (is_qebsm(q))
return qdio_do_sqbs(q, state, bufnr, count);
@@ -345,7 +335,6 @@
/* hipersocket busy condition */
if (unlikely(*busy_bit)) {
- WARN_ON(queue_type(q) != QDIO_IQDIO_QFMT || cc != 2);
retries++;
if (!start_time) {
@@ -559,7 +548,7 @@
DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in nop");
break;
default:
- BUG();
+ WARN_ON_ONCE(1);
}
out:
return q->first_to_check;
@@ -678,12 +667,10 @@
if (aob == NULL)
continue;
- BUG_ON(q->u.out.sbal_state == NULL);
q->u.out.sbal_state[b].flags |=
QDIO_OUTBUF_STATE_FLAG_PENDING;
q->u.out.aobs[b] = NULL;
} else if (state == SLSB_P_OUTPUT_EMPTY) {
- BUG_ON(q->u.out.sbal_state == NULL);
q->u.out.sbal_state[b].aob = NULL;
}
b = next_buf(b);
@@ -703,12 +690,11 @@
q->aobs[bufnr] = aob;
}
if (q->aobs[bufnr]) {
- BUG_ON(q->sbal_state == NULL);
q->sbal_state[bufnr].flags = QDIO_OUTBUF_STATE_FLAG_NONE;
q->sbal_state[bufnr].aob = q->aobs[bufnr];
q->aobs[bufnr]->user1 = (u64) q->sbal_state[bufnr].user;
phys_aob = virt_to_phys(q->aobs[bufnr]);
- BUG_ON(phys_aob & 0xFF);
+ WARN_ON_ONCE(phys_aob & 0xFF);
}
out:
@@ -809,8 +795,6 @@
goto out;
switch (state) {
- case SLSB_P_OUTPUT_PENDING:
- BUG();
case SLSB_P_OUTPUT_EMPTY:
/* the adapter got it */
DBF_DEV_EVENT(DBF_INFO, q->irq_ptr,
@@ -840,7 +824,7 @@
case SLSB_P_OUTPUT_HALTED:
break;
default:
- BUG();
+ WARN_ON_ONCE(1);
}
out:
@@ -912,7 +896,7 @@
static void __qdio_outbound_processing(struct qdio_q *q)
{
qperf_inc(q, tasklet_outbound);
- BUG_ON(atomic_read(&q->nr_buf_used) < 0);
+ WARN_ON_ONCE(atomic_read(&q->nr_buf_used) < 0);
if (qdio_outbound_q_moved(q))
qdio_kick_handler(q);
@@ -1138,16 +1122,10 @@
irq_ptr->perf_stat.qdio_int++;
if (IS_ERR(irb)) {
- switch (PTR_ERR(irb)) {
- case -EIO:
- DBF_ERROR("%4x IO error", irq_ptr->schid.sch_no);
- qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
- wake_up(&cdev->private->wait_q);
- return;
- default:
- WARN_ON(1);
- return;
- }
+ DBF_ERROR("%4x IO error", irq_ptr->schid.sch_no);
+ qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
+ wake_up(&cdev->private->wait_q);
+ return;
}
qdio_irq_check_sense(irq_ptr, irb);
cstat = irb->scsw.cmd.cstat;
@@ -1173,7 +1151,7 @@
case QDIO_IRQ_STATE_STOPPED:
break;
default:
- WARN_ON(1);
+ WARN_ON_ONCE(1);
}
wake_up(&cdev->private->wait_q);
}
@@ -1227,7 +1205,7 @@
if (!irq_ptr)
return -ENODEV;
- BUG_ON(irqs_disabled());
+ WARN_ON_ONCE(irqs_disabled());
DBF_EVENT("qshutdown:%4x", cdev->private->schid.sch_no);
mutex_lock(&irq_ptr->setup_mutex);
@@ -1358,7 +1336,6 @@
irq_ptr->qdr = (struct qdr *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
if (!irq_ptr->qdr)
goto out_rel;
- WARN_ON((unsigned long)irq_ptr->qdr & 0xfff);
if (qdio_allocate_qs(irq_ptr, init_data->no_input_qs,
init_data->no_output_qs))
@@ -1597,9 +1574,7 @@
set:
count = set_buf_states(q, bufnr, SLSB_CU_INPUT_EMPTY, count);
-
used = atomic_add_return(count, &q->nr_buf_used) - count;
- BUG_ON(used + count > QDIO_MAX_BUFFERS_PER_Q);
if (need_siga_in(q))
return qdio_siga_input(q);
@@ -1624,7 +1599,6 @@
count = set_buf_states(q, bufnr, SLSB_CU_OUTPUT_PRIMED, count);
used = atomic_add_return(count, &q->nr_buf_used);
- BUG_ON(used > QDIO_MAX_BUFFERS_PER_Q);
if (used == QDIO_MAX_BUFFERS_PER_Q)
qperf_inc(q, outbound_queue_full);
@@ -1678,7 +1652,6 @@
{
struct qdio_irq *irq_ptr;
-
if (bufnr >= QDIO_MAX_BUFFERS_PER_Q || count > QDIO_MAX_BUFFERS_PER_Q)
return -EINVAL;
@@ -1721,8 +1694,6 @@
return -ENODEV;
q = irq_ptr->input_qs[nr];
- WARN_ON(queue_irqs_enabled(q));
-
clear_nonshared_ind(irq_ptr);
qdio_stop_polling(q);
clear_bit(QDIO_QUEUE_IRQS_DISABLED, &q->u.in.queue_irq_state);
@@ -1769,7 +1740,6 @@
if (!irq_ptr)
return -ENODEV;
q = irq_ptr->input_qs[nr];
- WARN_ON(queue_irqs_enabled(q));
/*
* Cannot rely on automatic sync after interrupt since queues may