NTFS: Optimize fs/ntfs/aops.c::ntfs_write_block() by extending the page

lock protection over the buffer submission for i/o which allows the
      removal of the get_bh()/put_bh() pairs for each buffer.

Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
This commit is contained in:
Anton Altaparmakov 2005-09-08 21:43:47 +01:00
parent bd45fdd209
commit 54b02eb01c
2 changed files with 6 additions and 10 deletions

View File

@ -81,6 +81,9 @@ ToDo/Notes:
only zeroes.
- Fixup handling of sparse, compressed, and encrypted attributes in
fs/ntfs/aops.c::ntfs_writepage().
- Optimize fs/ntfs/aops.c::ntfs_write_block() by extending the page
lock protection over the buffer submission for i/o which allows the
removal of the get_bh()/put_bh() pairs for each buffer.
2.1.23 - Implement extension of resident files and make writing safe as well as
many bug fixes, cleanups, and enhancements...

View File

@ -735,7 +735,7 @@ lock_retry_remap:
/* For the error case, need to reset bh to the beginning. */
bh = head;
/* Just an optimization, so ->readpage() isn't called later. */
/* Just an optimization, so ->readpage() is not called later. */
if (unlikely(!PageUptodate(page))) {
int uptodate = 1;
do {
@ -751,7 +751,6 @@ lock_retry_remap:
/* Setup all mapped, dirty buffers for async write i/o. */
do {
get_bh(bh);
if (buffer_mapped(bh) && buffer_dirty(bh)) {
lock_buffer(bh);
if (test_clear_buffer_dirty(bh)) {
@ -789,14 +788,8 @@ lock_retry_remap:
BUG_ON(PageWriteback(page));
set_page_writeback(page); /* Keeps try_to_free_buffers() away. */
unlock_page(page);
/*
* Submit the prepared buffers for i/o. Note the page is unlocked,
* and the async write i/o completion handler can end_page_writeback()
* at any time after the *first* submit_bh(). So the buffers can then
* disappear...
*/
/* Submit the prepared buffers for i/o. */
need_end_writeback = TRUE;
do {
struct buffer_head *next = bh->b_this_page;
@ -804,9 +797,9 @@ lock_retry_remap:
submit_bh(WRITE, bh);
need_end_writeback = FALSE;
}
put_bh(bh);
bh = next;
} while (bh != head);
unlock_page(page);
/* If no i/o was started, need to end_page_writeback(). */
if (unlikely(need_end_writeback))