diff options
| author | Liu Bo <bo.li.liu@oracle.com> | 2017-09-13 12:18:22 -0600 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2017-10-30 12:27:56 +0100 |
| commit | 18fdc67900c5bfd1eeb41cfa50ea6f2eb7266f73 (patch) | |
| tree | fcfa26b0ddb1e771da0177539d4bbc1d13f7496d /fs/btrfs/disk-io.c | |
| parent | 6300463b14c1c2665674eb8f15843e5bb7a7ff84 (diff) | |
Btrfs: remove bio_flags which indicates a meta block of log-tree
Since both committing transaction and writing log-tree are doing
plugging on metadata IO, we can unify to use %sync_writers to benefit
both cases, instead of checking bio_flags while writing meta blocks of
log-tree.
We can remove this bio_flags because in order to write dirty blocks,
log tree also uses btrfs_write_marked_extents(), inside which we
have enabled %sync_writers, therefore, every write goes in a
synchronous way, so does checksuming.
Please also note that, bio_flags is applied per-context while
%sync_writers is applied per-inode, so this might incur some overhead, ie.
1) while log tree is flushing its dirty blocks via
btrfs_write_marked_extents(), in which %sync_writers is increased
by one.
2) in the meantime, some writeback operations may happen upon btrfs's
metadata inode, so these writes go synchronously, too.
However, AFAICS, the overhead is not a big one while the win is that
we unify the two places that needs synchronous way and remove a
special hack/flag.
This removes the bio_flags related stuff for writing log-tree.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/disk-io.c')
| -rw-r--r-- | fs/btrfs/disk-io.c | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 23442747363e..90310d9e647a 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1005,12 +1005,10 @@ static blk_status_t __btree_submit_bio_done(void *private_data, struct bio *bio, return ret; } -static int check_async_write(struct btrfs_inode *bi, unsigned long bio_flags) +static int check_async_write(struct btrfs_inode *bi) { if (atomic_read(&bi->sync_writers)) return 0; - if (bio_flags & EXTENT_BIO_TREE_LOG) - return 0; #ifdef CONFIG_X86 if (static_cpu_has(X86_FEATURE_XMM4_2)) return 0; @@ -1024,7 +1022,7 @@ static blk_status_t btree_submit_bio_hook(void *private_data, struct bio *bio, { struct inode *inode = private_data; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); - int async = check_async_write(BTRFS_I(inode), bio_flags); + int async = check_async_write(BTRFS_I(inode)); blk_status_t ret; if (bio_op(bio) != REQ_OP_WRITE) { |