[XFS] Improve xfsbufd delayed write submission patterns, after blktrace

[linux-2.6] / fs / xfs / linux-2.6 / xfs_buf.c

diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index 2af528dcfb0428ca93f2a5dced879e400682b876..f13503508c4618cf4c302e56ccd7756c1f5272b3 100644 (file)
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2005 Silicon Graphics, Inc.
+ * Copyright (c) 2000-2006 Silicon Graphics, Inc.
  * All Rights Reserved.
  *
  * This program is free software; you can redistribute it and/or
@@ -1681,6 +1681,7 @@ xfsbufd(
        xfs_buf_t               *bp, *n;
        struct list_head        *dwq = &target->bt_delwrite_queue;
        spinlock_t              *dwlk = &target->bt_delwrite_lock;
+       int                     count;
 
        current->flags |= PF_MEMALLOC;
 
@@ -1696,6 +1697,7 @@ xfsbufd(
                schedule_timeout_interruptible(
                        xfs_buf_timer_centisecs * msecs_to_jiffies(10));
 
+               count = 0;
                age = xfs_buf_age_centisecs * msecs_to_jiffies(10);
                spin_lock(dwlk);
                list_for_each_entry_safe(bp, n, dwq, b_list) {
@@ -1711,9 +1713,11 @@ xfsbufd(
                                        break;
                                }
 
-                               bp->b_flags &= ~(XBF_DELWRI|_XBF_DELWRI_Q);
+                               bp->b_flags &= ~(XBF_DELWRI|_XBF_DELWRI_Q|
+                                                _XBF_RUN_QUEUES);
                                bp->b_flags |= XBF_WRITE;
-                               list_move(&bp->b_list, &tmp);
+                               list_move_tail(&bp->b_list, &tmp);
+                               count++;
                        }
                }
                spin_unlock(dwlk);
@@ -1724,12 +1728,12 @@ xfsbufd(
 
                        list_del_init(&bp->b_list);
                        xfs_buf_iostrategy(bp);
-
-                       blk_run_address_space(target->bt_mapping);
                }
 
                if (as_list_len > 0)
                        purge_addresses();
+               if (count)
+                       blk_run_address_space(target->bt_mapping);
 
                clear_bit(XBT_FORCE_FLUSH, &target->bt_flags);
        } while (!kthread_should_stop());
@@ -1767,7 +1771,7 @@ xfs_flush_buftarg(
                        continue;
                }
 
-               list_move(&bp->b_list, &tmp);
+               list_move_tail(&bp->b_list, &tmp);
        }
        spin_unlock(dwlk);
 
@@ -1776,7 +1780,7 @@ xfs_flush_buftarg(
         */
        list_for_each_entry_safe(bp, n, &tmp, b_list) {
                xfs_buf_lock(bp);
-               bp->b_flags &= ~(XBF_DELWRI|_XBF_DELWRI_Q);
+               bp->b_flags &= ~(XBF_DELWRI|_XBF_DELWRI_Q|_XBF_RUN_QUEUES);
                bp->b_flags |= XBF_WRITE;
                if (wait)
                        bp->b_flags &= ~XBF_ASYNC;
@@ -1786,6 +1790,9 @@ xfs_flush_buftarg(
                xfs_buf_iostrategy(bp);
        }
 
+       if (wait)
+               blk_run_address_space(target->bt_mapping);
+
        /*
         * Remaining list items must be flushed before returning
         */
@@ -1797,9 +1804,6 @@ xfs_flush_buftarg(
                xfs_buf_relse(bp);
        }
 
-       if (wait)
-               blk_run_address_space(target->bt_mapping);
-
        return pincount;
 }