xfs: Don't issue buffer IO direct from AIL push V2

[pandora-kernel.git] / fs / xfs / xfs_trans_ail.c

diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c
index 2ffc570..e799824 100644 (file)
--- a/fs/xfs/xfs_trans_ail.c
+++ b/fs/xfs/xfs_trans_ail.c
@@ -237,14 +237,15 @@ out:
 }
 
 /*
- * Function that does the work of pushing on the AIL
+ * xfsaild_push does the work of pushing on the AIL.  Returning a timeout of
+ * zero indicates that the caller should sleep until woken.
  */
 long
 xfsaild_push(
        struct xfs_ail  *ailp,
        xfs_lsn_t       *last_lsn)
 {
-       long            tout = 1000; /* milliseconds */
+       long            tout = 0;
        xfs_lsn_t       last_pushed_lsn = *last_lsn;
        xfs_lsn_t       target =  ailp->xa_target;
        xfs_lsn_t       lsn;
@@ -252,6 +253,7 @@ xfsaild_push(
        int             flush_log, count, stuck;
        xfs_mount_t     *mp = ailp->xa_mount;
        struct xfs_ail_cursor   *cur = &ailp->xa_cursors;
+       int             push_xfsbufd = 0;
 
        spin_lock(&ailp->xa_lock);
        xfs_trans_ail_cursor_init(ailp, cur);
@@ -262,7 +264,7 @@ xfsaild_push(
                 */
                xfs_trans_ail_cursor_done(ailp, cur);
                spin_unlock(&ailp->xa_lock);
-               last_pushed_lsn = 0;
+               *last_lsn = 0;
                return tout;
        }
 
@@ -279,7 +281,6 @@ xfsaild_push(
         * prevents use from spinning when we can't do anything or there is
         * lots of contention on the AIL lists.
         */
-       tout = 10;
        lsn = lip->li_lsn;
        flush_log = stuck = count = 0;
        while ((XFS_LSN_CMP(lip->li_lsn, target) < 0)) {
@@ -308,6 +309,7 @@ xfsaild_push(
                        XFS_STATS_INC(xs_push_ail_pushbuf);
                        IOP_PUSHBUF(lip);
                        last_pushed_lsn = lsn;
+                       push_xfsbufd = 1;
                        break;
 
                case XFS_ITEM_PINNED:
@@ -322,12 +324,6 @@ xfsaild_push(
                        stuck++;
                        break;
 
-               case XFS_ITEM_FLUSHING:
-                       XFS_STATS_INC(xs_push_ail_flushing);
-                       last_pushed_lsn = lsn;
-                       stuck++;
-                       break;
-
                default:
                        ASSERT(0);
                        break;
@@ -371,19 +367,24 @@ xfsaild_push(
                 * move forward in the AIL.
                 */
                XFS_STATS_INC(xs_push_ail_flush);
-               xfs_log_force(mp, (xfs_lsn_t)0, XFS_LOG_FORCE);
+               xfs_log_force(mp, 0);
+       }
+
+       if (push_xfsbufd) {
+               /* we've got delayed write buffers to flush */
+               wake_up_process(mp->m_ddev_targp->bt_task);
        }
 
        if (!count) {
                /* We're past our target or empty, so idle */
-               tout = 1000;
+               last_pushed_lsn = 0;
        } else if (XFS_LSN_CMP(lsn, target) >= 0) {
                /*
                 * We reached the target so wait a bit longer for I/O to
                 * complete and remove pushed items from the AIL before we
                 * start the next scan from the start of the AIL.
                 */
-               tout += 20;
+               tout = 50;
                last_pushed_lsn = 0;
        } else if ((stuck * 100) / count > 90) {
                /*
@@ -395,11 +396,14 @@ xfsaild_push(
                 * Backoff a bit more to allow some I/O to complete before
                 * continuing from where we were.
                 */
-               tout += 10;
+               tout = 20;
+       } else {
+               /* more to do, but wait a short while before continuing */
+               tout = 10;
        }
        *last_lsn = last_pushed_lsn;
        return tout;
-}      /* xfsaild_push */
+}
 
 
 /*