btrfs_check_shared looks up parents of a given extent and uses ulists for that. These are allocated and freed repeatedly. Preallocation in the caller will avoid the overhead and also allow us to use the GFP_KERNEL as it is happens before the extent locks are taken.
Signed-off-by: David Sterba <[email protected]> --- fs/btrfs/backref.c | 17 ++++++----------- fs/btrfs/backref.h | 3 ++- fs/btrfs/extent_io.c | 15 +++++++++++++-- 3 files changed, 21 insertions(+), 14 deletions(-) diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index 982152d3f920..89116afda7a2 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -1465,12 +1465,11 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans, * * Return: 0 if extent is not shared, 1 if it is shared, < 0 on error. */ -int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr) +int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr, + struct ulist *roots, struct ulist *tmp) { struct btrfs_fs_info *fs_info = root->fs_info; struct btrfs_trans_handle *trans; - struct ulist *tmp = NULL; - struct ulist *roots = NULL; struct ulist_iterator uiter; struct ulist_node *node; struct seq_list elem = SEQ_LIST_INIT(elem); @@ -1481,12 +1480,8 @@ int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr) .share_count = 0, }; - tmp = ulist_alloc(GFP_NOFS); - roots = ulist_alloc(GFP_NOFS); - if (!tmp || !roots) { - ret = -ENOMEM; - goto out; - } + ulist_init(roots); + ulist_init(tmp); trans = btrfs_attach_transaction(root); if (IS_ERR(trans)) { @@ -1527,8 +1522,8 @@ int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr) up_read(&fs_info->commit_root_sem); } out: - ulist_free(tmp); - ulist_free(roots); + ulist_release(roots); + ulist_release(tmp); return ret; } diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h index 54d58988483a..777f61dc081e 100644 --- a/fs/btrfs/backref.h +++ b/fs/btrfs/backref.h @@ -57,7 +57,8 @@ int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid, u64 start_off, struct btrfs_path *path, struct btrfs_inode_extref **ret_extref, u64 *found_off); -int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr); +int btrfs_check_shared(struct btrfs_root *root, u64 inum, u64 bytenr, + struct ulist *roots, struct ulist *tmp_ulist); int __init btrfs_prelim_ref_init(void); void __cold btrfs_prelim_ref_exit(void); diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 13fca7bfc1f2..d70a602a5d48 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -4557,6 +4557,13 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, return -ENOMEM; path->leave_spinning = 1; + roots = ulist_alloc(GFP_KERNEL); + tmp_ulist = ulist_alloc(GFP_KERNEL); + if (!roots || !tmp_ulist) { + ret = -ENOMEM; + goto out_free_ulist; + } + start = round_down(start, btrfs_inode_sectorsize(inode)); len = round_up(max, btrfs_inode_sectorsize(inode)) - start; @@ -4568,7 +4575,7 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, btrfs_ino(BTRFS_I(inode)), -1, 0); if (ret < 0) { btrfs_free_path(path); - return ret; + goto out_free_ulist; } else { WARN_ON(!ret); if (ret == 1) @@ -4677,7 +4684,7 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, */ ret = btrfs_check_shared(root, btrfs_ino(BTRFS_I(inode)), - bytenr); + bytenr, roots, tmp_ulist); if (ret < 0) goto out_free; if (ret) @@ -4723,6 +4730,10 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, btrfs_free_path(path); unlock_extent_cached(&BTRFS_I(inode)->io_tree, start, start + len - 1, &cached_state); + +out_free_ulist: + ulist_free(roots); + ulist_free(tmp_ulist); return ret; } -- 2.21.0
