If we could not allocate a block in the "goal" group, we continue the search in the rest groups:find a new reservation window, allocate a block from there. Since we could not allocate a block from the goal group anyway, skip the group where the number of free blocks is less than half of window size, there could be a better place to make a reservation.
---
linux-2.6.9-rc4-mm1-ming/fs/ext3/balloc.c | 12 +++++++++---
1 files changed, 9 insertions(+), 3 deletions(-)
diff -puN fs/ext3/balloc.c~ext3_skip_reservation_in_full_group fs/ext3/balloc.c
--- linux-2.6.9-rc4-mm1/fs/ext3/balloc.c~ext3_skip_reservation_in_full_group 2004-10-18 22:28:11.723757688 -0700
+++ linux-2.6.9-rc4-mm1-ming/fs/ext3/balloc.c 2004-10-18 22:28:11.732756320 -0700
@@ -1154,6 +1154,7 @@ int ext3_new_block(handle_t *handle, str
struct ext3_sb_info *sbi;
struct reserve_window_node *my_rsv = NULL;
struct reserve_window_node *rsv = &EXT3_I(inode)->i_rsv_window;
+ unsigned short windowsz = 0;
#ifdef EXT3FS_DEBUG
static int goal_hits, goal_attempts;
#endif
@@ -1185,9 +1186,9 @@ int ext3_new_block(handle_t *handle, str
* command EXT3_IOC_SETRSVSZ to set the window size to 0 to turn off
* reservation on that particular file)
*/
+ windowsz = atomic_read(&rsv->rsv_goal_size);
if (test_opt(sb, RESERVATION) &&
- S_ISREG(inode->i_mode) &&
- (atomic_read(&rsv->rsv_goal_size) > 0))
+ S_ISREG(inode->i_mode) && (windowsz > 0))
my_rsv = rsv;
if (!ext3_has_free_blocks(sbi)) {
*errp = -ENOSPC;
@@ -1240,7 +1241,12 @@ retry:
goto out;
}
free_blocks = le16_to_cpu(gdp->bg_free_blocks_count);
- if (free_blocks <= 0)
+ /*
+ * skip this group if the number of
+ * free blocks is less than half of the reservation
+ * window size.
+ */
+ if (free_blocks <= (windowsz/2))
continue;
brelse(bitmap_bh);
_