This feature works on our crucial write endio path, so if we've got
lots of fragments to process, it will be kind of a disaster to the
performance, so I make such a change.
One can benifit from it while mounting with '-o snap_aware_defrag'.
Signed-off-by: Liu Bo <bo.li.liu@xxxxxxxxxx>
---
fs/btrfs/ctree.h | 1 +
fs/btrfs/inode.c | 16 ++++++++++------
fs/btrfs/ioctl.c | 5 +++--
fs/btrfs/super.c | 12 ++++++++++--
4 files changed, 24 insertions(+), 10 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 926c9ff..f9cd9c9 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1756,6 +1756,7 @@ struct btrfs_ioctl_defrag_range_args {
#define BTRFS_MOUNT_CHECK_INTEGRITY (1 << 20)
#define BTRFS_MOUNT_CHECK_INTEGRITY_INCLUDING_EXTENT_DATA (1 << 21)
#define BTRFS_MOUNT_PANIC_ON_FATAL_ERROR (1 << 22)
+#define BTRFS_MOUNT_SA_DEFRAG (1 << 23)
#define btrfs_clear_opt(o, opt) ((o) &= ~BTRFS_MOUNT_##opt)
#define btrfs_set_opt(o, opt) ((o) |= BTRFS_MOUNT_##opt)
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 35e6993..069499e 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2488,13 +2488,17 @@ static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
ordered_extent->file_offset + ordered_extent->len - 1,
0, &cached_state);
- ret = test_range_bit(io_tree, ordered_extent->file_offset,
- ordered_extent->file_offset + ordered_extent->len - 1,
- EXTENT_DEFRAG, 1, cached_state);
- if (ret && btrfs_root_last_snapshot(&root->root_item) >=
+ if (btrfs_test_opt(root, SA_DEFRAG)) {
+ ret = test_range_bit(io_tree, ordered_extent->file_offset,
+ ordered_extent->file_offset +
+ ordered_extent->len - 1,
+ EXTENT_DEFRAG, 1, cached_state);
+ if (ret &&
+ btrfs_root_last_snapshot(&root->root_item) >=
BTRFS_I(inode)->generation) {
- /* the inode is shared */
- new = record_old_file_extents(inode, ordered_extent);
+ /* the inode is shared */
+ new = record_old_file_extents(inode, ordered_extent);
+ }
}
if (nolock)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 6116880..1367165 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1058,8 +1058,9 @@ again:
}
- set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
- &cached_state, GFP_NOFS);
+ if (btrfs_test_opt(BTRFS_I(inode)->root, SA_DEFRAG))
+ set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start,
+ page_end - 1, &cached_state, GFP_NOFS);
unlock_extent_cached(&BTRFS_I(inode)->io_tree,
page_start, page_end - 1, &cached_state,
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 915ac14..24eac5f 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -308,8 +308,8 @@ enum {
Opt_compress_type, Opt_compress_force, Opt_compress_force_type,
Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard,
Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed,
- Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, Opt_inode_cache,
- Opt_no_space_cache, Opt_recovery, Opt_skip_balance,
+ Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, Opt_sa_defrag,
+ Opt_inode_cache, Opt_no_space_cache, Opt_recovery, Opt_skip_balance,
Opt_check_integrity, Opt_check_integrity_including_extent_data,
Opt_check_integrity_print_mask, Opt_fatal_errors,
Opt_err,
@@ -344,6 +344,7 @@ static match_table_t tokens = {
{Opt_enospc_debug, "enospc_debug"},
{Opt_subvolrootid, "subvolrootid=%d"},
{Opt_defrag, "autodefrag"},
+ {Opt_sa_defrag, "snap_aware_defrag"},
{Opt_inode_cache, "inode_cache"},
{Opt_no_space_cache, "nospace_cache"},
{Opt_recovery, "recovery"},
@@ -564,6 +565,11 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
printk(KERN_INFO "btrfs: enabling auto defrag\n");
btrfs_set_opt(info->mount_opt, AUTO_DEFRAG);
break;
+ case Opt_sa_defrag:
+ printk(KERN_INFO "btrfs: enabling snapshot-aware"
+ " defrag\n");
+ btrfs_set_opt(info->mount_opt, SA_DEFRAG);
+ break;
case Opt_recovery:
printk(KERN_INFO "btrfs: enabling auto recovery\n");
btrfs_set_opt(info->mount_opt, RECOVERY);
@@ -935,6 +941,8 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry)
seq_puts(seq, ",enospc_debug");
if (btrfs_test_opt(root, AUTO_DEFRAG))
seq_puts(seq, ",autodefrag");
+ if (btrfs_test_opt(root, SA_DEFRAG))
+ seq_puts(seq, ",snap_aware_defrag");
if (btrfs_test_opt(root, INODE_MAP_CACHE))
seq_puts(seq, ",inode_cache");
if (btrfs_test_opt(root, SKIP_BALANCE))
--
1.7.7.6
--
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