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btrfs: remove unnecessary @nr_written parameters

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We use @nr_written to record how many pages have been started by
btrfs_run_delalloc_range().

Currently there are only two cases that would populate @nr_written:

- Inline extent creation
- Compressed write

But both cases will also set @page_started to one.

In fact, in writepage_delalloc() we have the following code, showing
that @nr_written is really only utilized for above two cases:

	/* did the fill delalloc function already unlock and start
	 * the IO?
	 */
	if (page_started) {
		/*
		 * we've unlocked the page, so we can't update
		 * the mapping's writeback index, just update
		 * nr_to_write.
		 */
		wbc->nr_to_write -= nr_written;
		return 1;
	}

But for such cases, writepage_delalloc() will return 1, and exit
__extent_writepage() without going through __extent_writepage_io().

Thus this means, inside __extent_writepage_io(), we always get
@nr_written as 0.

So this patch is going to remove the unnecessary parameter from the
following functions:

- writepage_delalloc()

  As @nr_written passed in is always the initial value 0.

  Although inside that function, we still need a local @nr_written
  to update wbc->nr_to_write.

- __extent_writepage_io()

  As explained above, @nr_written passed in can only be 0.

  This also means we can remove one update_nr_written() call.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Qu Wenruo 2021-11-12 13:33:14 +08:00 committed by David Sterba
parent 9270501c16
commit 83f1b68002
1 changed files with 11 additions and 16 deletions
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27
fs/btrfs/extent_io.c
View File

@ -3785,12 +3785,13 @@ static void update_nr_written(struct writeback_control *wbc,
* This returns < 0 if there were errors (page still locked)
*/
static noinline_for_stack int writepage_delalloc(struct btrfs_inode *inode,
struct page *page, struct writeback_control *wbc,
unsigned long *nr_written)
struct page *page, struct writeback_control *wbc)
{
const u64 page_end = page_offset(page) + PAGE_SIZE - 1;
u64 delalloc_start = page_offset(page);
u64 delalloc_to_write = 0;
/* How many pages are started by btrfs_run_delalloc_range() */
unsigned long nr_written = 0;
int ret;
int page_started = 0;
@ -3806,7 +3807,7 @@ static noinline_for_stack int writepage_delalloc(struct btrfs_inode *inode,
continue;
}
ret = btrfs_run_delalloc_range(inode, page, delalloc_start,
delalloc_end, &page_started, nr_written, wbc);
delalloc_end, &page_started, &nr_written, wbc);
if (ret) {
btrfs_page_set_error(inode->root->fs_info, page,
page_offset(page), PAGE_SIZE);
@ -3829,16 +3830,13 @@ static noinline_for_stack int writepage_delalloc(struct btrfs_inode *inode,
thresh);
}
/* did the fill delalloc function already unlock and start
* the IO?
*/
/* Did btrfs_run_dealloc_range() already unlock and start the IO? */
if (page_started) {
/*
* we've unlocked the page, so we can't update
* the mapping's writeback index, just update
* nr_to_write.
* We've unlocked the page, so we can't update the mapping's
* writeback index, just update nr_to_write.
*/
wbc->nr_to_write -= *nr_written;
wbc->nr_to_write -= nr_written;
return 1;
}
@ -3910,7 +3908,6 @@ static noinline_for_stack int __extent_writepage_io(struct btrfs_inode *inode,
struct writeback_control *wbc,
struct extent_page_data *epd,
loff_t i_size,
unsigned long nr_written,
int *nr_ret)
{
struct btrfs_fs_info *fs_info = inode->root->fs_info;
@ -3929,7 +3926,6 @@ static noinline_for_stack int __extent_writepage_io(struct btrfs_inode *inode,
if (ret) {
/* Fixup worker will requeue */
redirty_page_for_writepage(wbc, page);
update_nr_written(wbc, nr_written);
unlock_page(page);
return 1;
}
@ -3938,7 +3934,7 @@ static noinline_for_stack int __extent_writepage_io(struct btrfs_inode *inode,
* we don't want to touch the inode after unlocking the page,
* so we update the mapping writeback index now
*/
update_nr_written(wbc, nr_written + 1);
update_nr_written(wbc, 1);
while (cur <= end) {
u64 disk_bytenr;
@ -4076,7 +4072,6 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
size_t pg_offset;
loff_t i_size = i_size_read(inode);
unsigned long end_index = i_size >> PAGE_SHIFT;
unsigned long nr_written = 0;
trace___extent_writepage(page, inode, wbc);
@ -4105,7 +4100,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
}
if (!epd->extent_locked) {
ret = writepage_delalloc(BTRFS_I(inode), page, wbc, &nr_written);
ret = writepage_delalloc(BTRFS_I(inode), page, wbc);
if (ret == 1)
return 0;
if (ret)
@ -4113,7 +4108,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
}
ret = __extent_writepage_io(BTRFS_I(inode), page, wbc, epd, i_size,
nr_written, &nr);
&nr);
if (ret == 1)
return 0;