[PATCH v2 02/11] btrfs: track ordered bytes instead of just dio ordered bytes

[Josef Bacik <josef@toxicpanda.com>]

We track dio_bytes because the shrink delalloc code needs to know if we
have more DIO in flight than we have normal buffered IO.  The reason for
this is because we can't "flush" DIO, we have to just wait on the
ordered extents to finish.

However this is true of all ordered extents.  If we have more ordered
space outstanding than dirty pages we should be waiting on ordered
extents.  We already are ok on this front technically, because we always
do a FLUSH_DELALLOC_WAIT loop, but I want to use the ordered counter in
the preemptive flushing code as well, so change this to count all
ordered bytes instead of just DIO ordered bytes.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 fs/btrfs/ctree.h        |  2 +-
 fs/btrfs/disk-io.c      |  8 ++++----
 fs/btrfs/ordered-data.c | 13 ++++++-------
 fs/btrfs/space-info.c   | 13 +++++++------
 4 files changed, 18 insertions(+), 18 deletions(-)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index aac3d6f4e35b..e817b3b3483d 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -790,7 +790,7 @@ struct btrfs_fs_info {
 	/* used to keep from writing metadata until there is a nice batch */
 	struct percpu_counter dirty_metadata_bytes;
 	struct percpu_counter delalloc_bytes;
-	struct percpu_counter dio_bytes;
+	struct percpu_counter ordered_bytes;
 	s32 dirty_metadata_batch;
 	s32 delalloc_batch;
 
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 764001609a15..61bb3321efaa 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1466,7 +1466,7 @@ void btrfs_free_fs_info(struct btrfs_fs_info *fs_info)
 {
 	percpu_counter_destroy(&fs_info->dirty_metadata_bytes);
 	percpu_counter_destroy(&fs_info->delalloc_bytes);
-	percpu_counter_destroy(&fs_info->dio_bytes);
+	percpu_counter_destroy(&fs_info->ordered_bytes);
 	percpu_counter_destroy(&fs_info->dev_replace.bio_counter);
 	btrfs_free_csum_hash(fs_info);
 	btrfs_free_stripe_hash_table(fs_info);
@@ -2748,7 +2748,7 @@ static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block
 	sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
 	sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
 
-	ret = percpu_counter_init(&fs_info->dio_bytes, 0, GFP_KERNEL);
+	ret = percpu_counter_init(&fs_info->ordered_bytes, 0, GFP_KERNEL);
 	if (ret)
 		return ret;
 
@@ -4055,9 +4055,9 @@ void __cold close_ctree(struct btrfs_fs_info *fs_info)
 		       percpu_counter_sum(&fs_info->delalloc_bytes));
 	}
 
-	if (percpu_counter_sum(&fs_info->dio_bytes))
+	if (percpu_counter_sum(&fs_info->ordered_bytes))
 		btrfs_info(fs_info, "at unmount dio bytes count %lld",
-			   percpu_counter_sum(&fs_info->dio_bytes));
+			   percpu_counter_sum(&fs_info->ordered_bytes));
 
 	btrfs_sysfs_remove_mounted(fs_info);
 	btrfs_sysfs_remove_fsid(fs_info->fs_devices);
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 87bac9ecdf4c..9a277a475a1c 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -202,11 +202,11 @@ static int __btrfs_add_ordered_extent(struct btrfs_inode *inode, u64 file_offset
 	if (type != BTRFS_ORDERED_IO_DONE && type != BTRFS_ORDERED_COMPLETE)
 		set_bit(type, &entry->flags);
 
-	if (dio) {
-		percpu_counter_add_batch(&fs_info->dio_bytes, num_bytes,
-					 fs_info->delalloc_batch);
+	percpu_counter_add_batch(&fs_info->ordered_bytes, num_bytes,
+				 fs_info->delalloc_batch);
+
+	if (dio)
 		set_bit(BTRFS_ORDERED_DIRECT, &entry->flags);
-	}
 
 	/* one ref for the tree */
 	refcount_set(&entry->refs, 1);
@@ -480,9 +480,8 @@ void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode,
 		btrfs_delalloc_release_metadata(btrfs_inode, entry->num_bytes,
 						false);
 
-	if (test_bit(BTRFS_ORDERED_DIRECT, &entry->flags))
-		percpu_counter_add_batch(&fs_info->dio_bytes, -entry->num_bytes,
-					 fs_info->delalloc_batch);
+	percpu_counter_add_batch(&fs_info->ordered_bytes, -entry->num_bytes,
+				 fs_info->delalloc_batch);
 
 	tree = &btrfs_inode->ordered_tree;
 	spin_lock_irq(&tree->lock);
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index f1a525251c2a..96d40f8df246 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -489,7 +489,7 @@ static void shrink_delalloc(struct btrfs_fs_info *fs_info,
 {
 	struct btrfs_trans_handle *trans;
 	u64 delalloc_bytes;
-	u64 dio_bytes;
+	u64 ordered_bytes;
 	u64 items;
 	long time_left;
 	int loops;
@@ -513,8 +513,8 @@ static void shrink_delalloc(struct btrfs_fs_info *fs_info,
 
 	delalloc_bytes = percpu_counter_sum_positive(
 						&fs_info->delalloc_bytes);
-	dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
-	if (delalloc_bytes == 0 && dio_bytes == 0) {
+	ordered_bytes = percpu_counter_sum_positive(&fs_info->ordered_bytes);
+	if (delalloc_bytes == 0 && ordered_bytes == 0) {
 		if (trans)
 			return;
 		if (wait_ordered)
@@ -527,11 +527,11 @@ static void shrink_delalloc(struct btrfs_fs_info *fs_info,
 	 * ordered extents, otherwise we'll waste time trying to flush delalloc
 	 * that likely won't give us the space back we need.
 	 */
-	if (dio_bytes > delalloc_bytes)
+	if (ordered_bytes > delalloc_bytes)
 		wait_ordered = true;
 
 	loops = 0;
-	while ((delalloc_bytes || dio_bytes) && loops < 3) {
+	while ((delalloc_bytes || ordered_bytes) && loops < 3) {
 		btrfs_start_delalloc_roots(fs_info, items);
 
 		loops++;
@@ -553,7 +553,8 @@ static void shrink_delalloc(struct btrfs_fs_info *fs_info,
 
 		delalloc_bytes = percpu_counter_sum_positive(
 						&fs_info->delalloc_bytes);
-		dio_bytes = percpu_counter_sum_positive(&fs_info->dio_bytes);
+		ordered_bytes = percpu_counter_sum_positive(
+						&fs_info->ordered_bytes);
 	}
 }
 
-- 
2.26.2