src/patches/suse-2.6.27.25/patches.fixes/block-use-round_jiffies_up

   1 Subject: Block: use round_jiffies_up()
   2 From: Alan Stern <stern@rowland.harvard.edu>
   3 Date: Thu Nov 6 08:42:49 2008 +0100:
   4 Git: 7838c15b8dd18e78a523513749e5b54bda07b0cb
   5 References: bnc#464155
   6
   7 This patch (as1159b) changes the timeout routines in the block core to
   8 use round_jiffies_up().  There's no point in rounding the timer
   9 deadline down, since if it expires too early we will have to restart
  10 it.
  11
  12 The patch also removes some unnecessary tests when a request is
  13 removed from the queue's timer list.
  14
  15 Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
  16 Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
  17 Signed-off-by: Hannes Reinecke <hare@suse.de>
  18
  19 ---
  20  block/blk-timeout.c |   20 +++-----------------
  21  1 file changed, 3 insertions(+), 17 deletions(-)
  22
  23 --- a/block/blk-timeout.c
  24 +++ b/block/blk-timeout.c
  25 @@ -16,14 +16,7 @@ void blk_delete_timer(struct request *re
  26  {
  27         struct request_queue *q = req->q;
  28
  29 -       /*
  30 -        * Nothing to detach
  31 -        */
  32 -       if (!q->rq_timed_out_fn || !req->deadline)
  33 -               return;
  34 -
  35         list_del_init(&req->timeout_list);
  36 -
  37         if (list_empty(&q->timeout_list))
  38                 del_timer(&q->timeout);
  39  }
  40 @@ -83,7 +76,7 @@ void blk_rq_timed_out_timer(unsigned lon
  41         }
  42
  43         if (next_set && !list_empty(&q->timeout_list))
  44 -               mod_timer(&q->timeout, round_jiffies(next));
  45 +               mod_timer(&q->timeout, round_jiffies_up(next));
  46
  47         spin_unlock_irqrestore(q->queue_lock, flags);
  48  }
  49 @@ -139,17 +132,10 @@ void blk_add_timer(struct request *req)
  50
  51         /*
  52          * If the timer isn't already pending or this timeout is earlier
  53 -        * than an existing one, modify the timer. Round to next nearest
  54 +        * than an existing one, modify the timer. Round up to next nearest
  55          * second.
  56          */
  57 -       expiry = round_jiffies(req->deadline);
  58 -
  59 -       /*
  60 -        * We use ->deadline == 0 to detect whether a timer was added or
  61 -        * not, so just increase to next jiffy for that specific case
  62 -        */
  63 -       if (unlikely(!req->deadline))
  64 -               req->deadline = 1;
  65 +       expiry = round_jiffies_up(req->deadline);
  66
  67         if (!timer_pending(&q->timeout) ||
  68             time_before(expiry, q->timeout.expires))