| Message ID | 6e19647f2f3fb86f042e43162d55ceefe7c85d3e.1496792333.git.osandov@fb.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jun 06, 2017 at 04:45:29PM -0700, Omar Sandoval wrote: > From: Omar Sandoval <osandov@fb.com> > > Currently, we only increment total_bytes_pinned in > btrfs_free_tree_block() when dropping the last reference on the block. > However, when the delayed ref is run later, we will decrement > total_bytes_pinned regardless of whether it was the last reference or > not. This causes the counter to underflow when the reference we dropped > was not the last reference. Fix it by incrementing the counter > unconditionally, which is what btrfs_free_extent() does. This makes > total_bytes_pinned an overestimate when references to shared extents are > dropped, but in the worst case this will just make us try to commit the > transaction to try to free up space and find we didn't free enough. > I recognize the same problem, the patch looks good. Reviewed-by: Liu Bo <bo.li.liu@oracle.com> -liubo > Signed-off-by: Omar Sandoval <osandov@fb.com> > --- > fs/btrfs/extent-tree.c | 17 ++++++++--------- > 1 file changed, 8 insertions(+), 9 deletions(-) > > diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c > index 9cff937415cb..52f3a0486e64 100644 > --- a/fs/btrfs/extent-tree.c > +++ b/fs/btrfs/extent-tree.c > @@ -7178,10 +7178,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, > BUG_ON(ret); /* -ENOMEM */ > } > > - if (!last_ref) > - return; > - > - if (btrfs_header_generation(buf) == trans->transid) { > + if (last_ref && btrfs_header_generation(buf) == trans->transid) { > struct btrfs_block_group_cache *cache; > > if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) { > @@ -7212,11 +7209,13 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, > add_pinned_bytes(fs_info, buf->len, btrfs_header_level(buf), > root->root_key.objectid); > > - /* > - * Deleting the buffer, clear the corrupt flag since it doesn't matter > - * anymore. > - */ > - clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags); > + if (last_ref) { > + /* > + * Deleting the buffer, clear the corrupt flag since it doesn't > + * matter anymore. > + */ > + clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags); > + } > } > > /* Can return -ENOMEM */ > -- > 2.13.0 > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 9cff937415cb..52f3a0486e64 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -7178,10 +7178,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, BUG_ON(ret); /* -ENOMEM */ } - if (!last_ref) - return; - - if (btrfs_header_generation(buf) == trans->transid) { + if (last_ref && btrfs_header_generation(buf) == trans->transid) { struct btrfs_block_group_cache *cache; if (root->root_key.objectid != BTRFS_TREE_LOG_OBJECTID) { @@ -7212,11 +7209,13 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, add_pinned_bytes(fs_info, buf->len, btrfs_header_level(buf), root->root_key.objectid); - /* - * Deleting the buffer, clear the corrupt flag since it doesn't matter - * anymore. - */ - clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags); + if (last_ref) { + /* + * Deleting the buffer, clear the corrupt flag since it doesn't + * matter anymore. + */ + clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags); + } } /* Can return -ENOMEM */