diff options
author | Mingming Cao <cmm@us.ibm.com> | 2006-03-26 09:37:59 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-03-26 16:57:01 (GMT) |
commit | d48589bfad0e60bff0aa3f9e4875983f607bd44b (patch) | |
tree | 3ec6d645847ea451b15abd6c9f1f27ce93591fd9 | |
parent | faa569763a7753e0a7cb8fd3919a62c0f7cc1e3c (diff) | |
download | linux-fsl-qoriq-d48589bfad0e60bff0aa3f9e4875983f607bd44b.tar.xz |
[PATCH] ext3_get_blocks: Adjust reservation window size for mblocks
Optimize the block reservation and the multiple block allocation: with the
knowledge of the total number of blocks ahead, set or adjust the reservation
window size properly (based on the number of blocks needed) before block
allocation happens: if there isn't any reservation yet, make sure the
reservation window equals to or greater than the number of blocks needed,
before create an reservation window; if a reservation window is already
exists, try to extends the window size to match the number of blocks to
allocate. This could increase the possibility of completing multiple blocks
allocation in a single request, as blocks are only allocated in the range of
the inode's reservation window.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r-- | fs/ext3/balloc.c | 32 |
1 files changed, 31 insertions, 1 deletions
diff --git a/fs/ext3/balloc.c b/fs/ext3/balloc.c index 7a2c719..77927d6 100644 --- a/fs/ext3/balloc.c +++ b/fs/ext3/balloc.c @@ -1011,6 +1011,31 @@ retry: goto retry; } +static void try_to_extend_reservation(struct ext3_reserve_window_node *my_rsv, + struct super_block *sb, int size) +{ + struct ext3_reserve_window_node *next_rsv; + struct rb_node *next; + spinlock_t *rsv_lock = &EXT3_SB(sb)->s_rsv_window_lock; + + if (!spin_trylock(rsv_lock)) + return; + + next = rb_next(&my_rsv->rsv_node); + + if (!next) + my_rsv->rsv_end += size; + else { + next_rsv = list_entry(next, struct ext3_reserve_window_node, rsv_node); + + if ((next_rsv->rsv_start - my_rsv->rsv_end - 1) >= size) + my_rsv->rsv_end += size; + else + my_rsv->rsv_end = next_rsv->rsv_start - 1; + } + spin_unlock(rsv_lock); +} + /* * This is the main function used to allocate a new block and its reservation * window. @@ -1095,6 +1120,8 @@ ext3_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle, while (1) { if (rsv_is_empty(&my_rsv->rsv_window) || (ret < 0) || !goal_in_my_reservation(&my_rsv->rsv_window, goal, group, sb)) { + if (my_rsv->rsv_goal_size < *count) + my_rsv->rsv_goal_size = *count; ret = alloc_new_reservation(my_rsv, goal, sb, group, bitmap_bh); if (ret < 0) @@ -1102,7 +1129,10 @@ ext3_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle, if (!goal_in_my_reservation(&my_rsv->rsv_window, goal, group, sb)) goal = -1; - } + } else if (goal > 0 && (my_rsv->rsv_end-goal+1) < *count) + try_to_extend_reservation(my_rsv, sb, + *count-my_rsv->rsv_end + goal - 1); + if ((my_rsv->rsv_start >= group_first_block + EXT3_BLOCKS_PER_GROUP(sb)) || (my_rsv->rsv_end < group_first_block)) BUG(); |