src/patches/suse-2.6.27.39/patches.arch/s390-17-perf-05-qdio_extract_all_primed_SBALs_at_once.patch

   1 From: Gerald Schaefer <geraldsc@de.ibm.com>
   2 Subject: [PATCH] qdio: extract all primed SBALs at once
   3 References: bnc#532063,LTC#55526
   4
   5 From: Jan Glauber <jang@linux.vnet.ibm.com>
   6
   7 For devices without QIOASSIST primed SBALS were extracted in a loop.
   8 Remove the loop since get_buf_states can already return more than
   9 one primed SBAL.
  10
  11 Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
  12
  13 Acked-by: John Jolly <jjolly@suse.de>
  14
  15 ---
  16  drivers/s390/cio/qdio_main.c |   34 ++++++----------------------------
  17  1 file changed, 6 insertions(+), 28 deletions(-)
  18
  19 Index: linux-sles11/drivers/s390/cio/qdio_main.c
  20 ===================================================================
  21 --- linux-sles11.orig/drivers/s390/cio/qdio_main.c
  22 +++ linux-sles11/drivers/s390/cio/qdio_main.c
  23 @@ -467,19 +467,13 @@ static int get_inbound_buffer_frontier(s
  24         count = min(atomic_read(&q->nr_buf_used), QDIO_MAX_BUFFERS_MASK);
  25         stop = add_buf(q->first_to_check, count);
  26
  27 -       /*
  28 -        * No siga sync here, as a PCI or we after a thin interrupt
  29 -        * will sync the queues.
  30 -        */
  31 -
  32 -       /* need to set count to 1 for non-qebsm */
  33 -       if (!is_qebsm(q))
  34 -               count = 1;
  35 -
  36 -check_next:
  37         if (q->first_to_check == stop)
  38                 goto out;
  39
  40 +       /*
  41 +        * No siga sync here, as a PCI or we after a thin interrupt
  42 +        * already sync'ed the queues.
  43 +        */
  44         count = get_buf_states(q, q->first_to_check, &state, count, 1);
  45         if (!count)
  46                 goto out;
  47 @@ -487,14 +481,9 @@ check_next:
  48         switch (state) {
  49         case SLSB_P_INPUT_PRIMED:
  50                 inbound_primed(q, count);
  51 -               /*
  52 -                * No siga-sync needed for non-qebsm here, as the inbound queue
  53 -                * will be synced on the next siga-r, resp.
  54 -                * tiqdio_is_inbound_q_done will do the siga-sync.
  55 -                */
  56                 q->first_to_check = add_buf(q->first_to_check, count);
  57                 atomic_sub(count, &q->nr_buf_used);
  58 -               goto check_next;
  59 +               break;
  60         case SLSB_P_INPUT_ERROR:
  61                 announce_buffer_error(q, count);
  62                 /* process the buffer, the upper layer will take care of it */
  63 @@ -653,11 +642,6 @@ static int get_outbound_buffer_frontier(
  64         count = min(atomic_read(&q->nr_buf_used), QDIO_MAX_BUFFERS_MASK);
  65         stop = add_buf(q->first_to_check, count);
  66
  67 -       /* need to set count to 1 for non-qebsm */
  68 -       if (!is_qebsm(q))
  69 -               count = 1;
  70 -
  71 -check_next:
  72         if (q->first_to_check == stop)
  73                 return q->first_to_check;
  74
  75 @@ -672,13 +656,7 @@ check_next:
  76
  77                 atomic_sub(count, &q->nr_buf_used);
  78                 q->first_to_check = add_buf(q->first_to_check, count);
  79 -               /*
  80 -                * We fetch all buffer states at once. get_buf_states may
  81 -                * return count < stop. For QEBSM we do not loop.
  82 -                */
  83 -               if (is_qebsm(q))
  84 -                       break;
  85 -               goto check_next;
  86 +               break;
  87         case SLSB_P_OUTPUT_ERROR:
  88                 announce_buffer_error(q, count);
  89                 /* process the buffer, the upper layer will take care of it */