On 23.05.2018 18:58, Josef Bacik wrote:
> From: Josef Bacik <jbacik@xxxxxx>
>
> Since we are waiting on all ordered extents at the start of the fsync()
> path we don't need to wait on any logged ordered extents, and we don't
> need to look up the checksums on the ordered extents as they will
> already be on disk prior to getting here. Rework this so we're only
> looking up and copying the on-disk checksums for the extent range we
> care about.
>
> Signed-off-by: Josef Bacik <jbacik@xxxxxx>
> ---
> fs/btrfs/tree-log.c | 118 +++++-----------------------------------------------
> 1 file changed, 10 insertions(+), 108 deletions(-)
>
> diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
> index 43758e30aa7a..791b5a731456 100644
> --- a/fs/btrfs/tree-log.c
> +++ b/fs/btrfs/tree-log.c
> @@ -4082,127 +4082,30 @@ static int extent_cmp(void *priv, struct list_head *a, struct list_head *b)
> return 0;
> }
>
> -static int wait_ordered_extents(struct btrfs_trans_handle *trans,
> - struct inode *inode,
> - struct btrfs_root *root,
> - const struct extent_map *em,
> - const struct list_head *logged_list,
> - bool *ordered_io_error)
> +static int log_extent_csums(struct btrfs_trans_handle *trans,
> + struct btrfs_inode *inode,
> + struct btrfs_root *root,
> + const struct extent_map *em)
> {
> struct btrfs_fs_info *fs_info = root->fs_info;
> - struct btrfs_ordered_extent *ordered;
> struct btrfs_root *log = root->log_root;
> - u64 mod_start = em->mod_start;
> - u64 mod_len = em->mod_len;
> - const bool skip_csum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM;
> u64 csum_offset;
> u64 csum_len;
> LIST_HEAD(ordered_sums);
> int ret = 0;
>
> - *ordered_io_error = false;
> -
> - if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
> + if (inode->flags & BTRFS_INODE_NODATASUM ||
> + test_bit(EXTENT_FLAG_PREALLOC, &em->flags) ||
> em->block_start == EXTENT_MAP_HOLE)
> return 0;
>
> - /*
> - * Wait far any ordered extent that covers our extent map. If it
> - * finishes without an error, first check and see if our csums are on
> - * our outstanding ordered extents.
> - */
> - list_for_each_entry(ordered, logged_list, log_list) {
> - struct btrfs_ordered_sum *sum;
> -
> - if (!mod_len)
> - break;
> -
> - if (ordered->file_offset + ordered->len <= mod_start ||
> - mod_start + mod_len <= ordered->file_offset)
> - continue;
> -
> - if (!test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags) &&
> - !test_bit(BTRFS_ORDERED_IOERR, &ordered->flags) &&
> - !test_bit(BTRFS_ORDERED_DIRECT, &ordered->flags)) {
> - const u64 start = ordered->file_offset;
> - const u64 end = ordered->file_offset + ordered->len - 1;
> -
> - WARN_ON(ordered->inode != inode);
> - filemap_fdatawrite_range(inode->i_mapping, start, end);
> - }
> -
> - wait_event(ordered->wait,
> - (test_bit(BTRFS_ORDERED_IO_DONE, &ordered->flags) ||
> - test_bit(BTRFS_ORDERED_IOERR, &ordered->flags)));
> -
> - if (test_bit(BTRFS_ORDERED_IOERR, &ordered->flags)) {
> - /*
> - * Clear the AS_EIO/AS_ENOSPC flags from the inode's
> - * i_mapping flags, so that the next fsync won't get
> - * an outdated io error too.
> - */
> - filemap_check_errors(inode->i_mapping);
> - *ordered_io_error = true;
> - break;
> - }
> - /*
> - * We are going to copy all the csums on this ordered extent, so
> - * go ahead and adjust mod_start and mod_len in case this
> - * ordered extent has already been logged.
> - */
> - if (ordered->file_offset > mod_start) {
> - if (ordered->file_offset + ordered->len >=
> - mod_start + mod_len)
> - mod_len = ordered->file_offset - mod_start;
> - /*
> - * If we have this case
> - *
> - * |--------- logged extent ---------|
> - * |----- ordered extent ----|
> - *
> - * Just don't mess with mod_start and mod_len, we'll
> - * just end up logging more csums than we need and it
> - * will be ok.
> - */
> - } else {
> - if (ordered->file_offset + ordered->len <
> - mod_start + mod_len) {
> - mod_len = (mod_start + mod_len) -
> - (ordered->file_offset + ordered->len);
> - mod_start = ordered->file_offset +
> - ordered->len;
> - } else {
> - mod_len = 0;
> - }
> - }
> -
> - if (skip_csum)
> - continue;
> -
> - /*
> - * To keep us from looping for the above case of an ordered
> - * extent that falls inside of the logged extent.
> - */
> - if (test_and_set_bit(BTRFS_ORDERED_LOGGED_CSUM,
> - &ordered->flags))
> - continue;
> -
> - list_for_each_entry(sum, &ordered->list, list) {
> - ret = btrfs_csum_file_blocks(trans, log, sum);
> - if (ret)
> - break;
> - }
> - }
> -
> - if (*ordered_io_error || !mod_len || ret || skip_csum)
> - return ret;
> -
> + /* If we're compressed we have to save the entire range of csums. */
> if (em->compress_type) {
> csum_offset = 0;
> csum_len = max(em->block_len, em->orig_block_len);
> } else {
> - csum_offset = mod_start - em->start;
> - csum_len = mod_len;
> + csum_offset = em->mod_start - em->start;
> + csum_len = em->mod_len;
> }
>
> /* block start is already adjusted for the file extent offset. */
> @@ -4244,8 +4147,7 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
> int extent_inserted = 0;
> bool ordered_io_err = false;
>
> - ret = wait_ordered_extents(trans, &inode->vfs_inode, root, em,
> - logged_list, &ordered_io_err);
> + ret = log_extent_csums(trans, inode, root, em);
With the following minor diff:
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index daf32dc94dc3..34d5b0630824 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -4064,11 +4064,9 @@ static int extent_cmp(void *priv, struct list_head *a, struct list_head *b)
static int log_extent_csums(struct btrfs_trans_handle *trans,
struct btrfs_inode *inode,
- struct btrfs_root *root,
+ struct btrfs_root *log,
const struct extent_map *em)
{
- struct btrfs_fs_info *fs_info = root->fs_info;
- struct btrfs_root *log = root->log_root;
u64 csum_offset;
u64 csum_len;
LIST_HEAD(ordered_sums);
@@ -4089,7 +4087,7 @@ static int log_extent_csums(struct btrfs_trans_handle *trans,
}
/* block start is already adjusted for the file extent offset. */
- ret = btrfs_lookup_csums_range(fs_info->csum_root,
+ ret = btrfs_lookup_csums_range(trans->fs_info->csum_root,
em->block_start + csum_offset,
em->block_start + csum_offset +
csum_len - 1, &ordered_sums, 0);
@@ -4125,7 +4123,7 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
int ret;
int extent_inserted = 0;
- ret = log_extent_csums(trans, inode, root, em);
+ ret = log_extent_csums(trans, inode, log, em);
if (ret)
return ret;
Bloat-o-meter reports:
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-55 (-55)
Function old new delta
btrfs_log_changed_extents.isra 4298 4243 -55
Total: Before=64999, After=64944, chg -0.08%
I suggest you incorporate it in the patch
> if (ret)
> return ret;
>
>
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