On Thu, Aug 30, 2018 at 01:41:59PM -0400, Josef Bacik wrote: > If we're allocating a new space cache inode it's likely going to be > under a transaction handle, so we need to use memalloc_nofs_save() in > order to avoid deadlocks, and more importantly lockdep messages that > make xfstests fail.
Could use a comment where we call memalloc_nofs_save(). Otherwise, Reviewed-by: Omar Sandoval <osan...@fb.com> > Signed-off-by: Josef Bacik <jo...@toxicpanda.com> > --- > fs/btrfs/free-space-cache.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c > index c3888c113d81..db93a5f035a0 100644 > --- a/fs/btrfs/free-space-cache.c > +++ b/fs/btrfs/free-space-cache.c > @@ -10,6 +10,7 @@ > #include <linux/math64.h> > #include <linux/ratelimit.h> > #include <linux/error-injection.h> > +#include <linux/sched/mm.h> > #include "ctree.h" > #include "free-space-cache.h" > #include "transaction.h" > @@ -47,6 +48,7 @@ static struct inode *__lookup_free_space_inode(struct > btrfs_root *root, > struct btrfs_free_space_header *header; > struct extent_buffer *leaf; > struct inode *inode = NULL; > + unsigned nofs_flag; > int ret; > > key.objectid = BTRFS_FREE_SPACE_OBJECTID; > @@ -68,7 +70,9 @@ static struct inode *__lookup_free_space_inode(struct > btrfs_root *root, > btrfs_disk_key_to_cpu(&location, &disk_key); > btrfs_release_path(path); > > + nofs_flag = memalloc_nofs_save(); > inode = btrfs_iget(fs_info->sb, &location, root, NULL); > + memalloc_nofs_restore(nofs_flag); > if (IS_ERR(inode)) > return inode; > > -- > 2.14.3 >
