s390/qdio: remove q->first_to_kick

q->first_to_kick is obsolete, and can be replaced by q->first_to_check.

Both cursors start off at 0. Out of the three code paths that update
first_to_check, the qdio_inspect_queue() path is irrelevant as it
doesn't even touch first_to_kick anymore.
This leaves us with the two tasklet-driven code paths. Here any update
to first_to_check is followed by a call to qdio_kick_handler(), which
advances first_to_kick by the same amount.

So the two cursors will differ only for a tiny moment. Drivers have no
way of deterministically observing this difference, and thus it doesn't
matter which of the cursors we use for reporting an error to q->handler.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

diff --git a/drivers/s390/cio/qdio.h b/drivers/s390/cio/qdio.h
index 66191e864b0b6aa6eb7ba529d409dc11d7c52d5a..eb13c479e11debe9fcd5e0a9b12e2e07ec354c77 100644 (file)
--- a/drivers/s390/cio/qdio.h
+++ b/drivers/s390/cio/qdio.h
@@ -221,9 +221,6 @@ struct qdio_q {
         */
        int first_to_check;
 
-       /* beginning position for calling the program */
-       int first_to_kick;
-
        /* number of buffers in use by the adapter */
        atomic_t nr_buf_used;
 

diff --git a/drivers/s390/cio/qdio_main.c b/drivers/s390/cio/qdio_main.c
index d9acf492f73ca1752115d112e67ae21ba8669819..b0e84fba54dd12783efae4916be6662425ad5b59 100644 (file)
--- a/drivers/s390/cio/qdio_main.c
+++ b/drivers/s390/cio/qdio_main.c
@@ -143,7 +143,7 @@ again:
                DBF_ERROR("%4x EQBS ERROR", SCH_NO(q));
                DBF_ERROR("%3d%3d%2d", count, tmp_count, nr);
                q->handler(q->irq_ptr->cdev, QDIO_ERROR_GET_BUF_STATE, q->nr,
-                          q->first_to_kick, count, q->irq_ptr->int_parm);
+                          q->first_to_check, count, q->irq_ptr->int_parm);
                return 0;
        }
 }
@@ -191,7 +191,7 @@ again:
                DBF_ERROR("%4x SQBS ERROR", SCH_NO(q));
                DBF_ERROR("%3d%3d%2d", count, tmp_count, nr);
                q->handler(q->irq_ptr->cdev, QDIO_ERROR_SET_BUF_STATE, q->nr,
-                          q->first_to_kick, count, q->irq_ptr->int_parm);
+                          q->first_to_check, count, q->irq_ptr->int_parm);
                return 0;
        }
 }
@@ -622,10 +622,9 @@ static inline unsigned long qdio_aob_for_buffer(struct qdio_output_q *q,
        return phys_aob;
 }
 
-static void qdio_kick_handler(struct qdio_q *q, unsigned int count)
+static void qdio_kick_handler(struct qdio_q *q, unsigned int start,
+                             unsigned int count)
 {
-       int start = q->first_to_kick;
-
        if (unlikely(q->irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
                return;
 
@@ -642,7 +641,6 @@ static void qdio_kick_handler(struct qdio_q *q, unsigned int count)
                   q->irq_ptr->int_parm);
 
        /* for the next time */
-       q->first_to_kick = add_buf(start, count);
        q->qdio_error = 0;
 }
 
@@ -666,9 +664,9 @@ static void __qdio_inbound_processing(struct qdio_q *q)
        if (count == 0)
                return;
 
+       qdio_kick_handler(q, start, count);
        start = add_buf(start, count);
        q->first_to_check = start;
-       qdio_kick_handler(q, count);
 
        if (!qdio_inbound_q_done(q, start)) {
                /* means poll time is not yet over */
@@ -824,7 +822,7 @@ static void __qdio_outbound_processing(struct qdio_q *q)
        count = qdio_outbound_q_moved(q, start);
        if (count) {
                q->first_to_check = add_buf(start, count);
-               qdio_kick_handler(q, count);
+               qdio_kick_handler(q, start, count);
        }
 
        if (queue_type(q) == QDIO_ZFCP_QFMT && !pci_out_supported(q->irq_ptr) &&
@@ -945,7 +943,6 @@ static void qdio_handle_activate_check(struct ccw_device *cdev,
 {
        struct qdio_irq *irq_ptr = cdev->private->qdio_data;
        struct qdio_q *q;
-       int count;
 
        DBF_ERROR("%4x ACT CHECK", irq_ptr->schid.sch_no);
        DBF_ERROR("intp :%lx", intparm);
@@ -960,9 +957,8 @@ static void qdio_handle_activate_check(struct ccw_device *cdev,
                goto no_handler;
        }
 
-       count = sub_buf(q->first_to_check, q->first_to_kick);
        q->handler(q->irq_ptr->cdev, QDIO_ERROR_ACTIVATE,
-                  q->nr, q->first_to_kick, count, irq_ptr->int_parm);
+                  q->nr, q->first_to_check, 0, irq_ptr->int_parm);
 no_handler:
        qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
        /*