On Thu, Jun 3, 2021 at 6:52 PM Jeff Layton <jlayton@xxxxxxxxxx> wrote:
>
> Turn some comments into lockdep asserts.
>
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> ---
> fs/ceph/snap.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
> index 2a63fb37778b..bc6c33d485e6 100644
> --- a/fs/ceph/snap.c
> +++ b/fs/ceph/snap.c
> @@ -65,6 +65,8 @@
> void ceph_get_snap_realm(struct ceph_mds_client *mdsc,
> struct ceph_snap_realm *realm)
> {
> + lockdep_assert_held_write(&mdsc->snap_rwsem);
> +
> dout("get_realm %p %d -> %d\n", realm,
> atomic_read(&realm->nref), atomic_read(&realm->nref)+1);
> /*
> @@ -113,6 +115,8 @@ static struct ceph_snap_realm *ceph_create_snap_realm(
> {
> struct ceph_snap_realm *realm;
>
> + lockdep_assert_held_write(&mdsc->snap_rwsem);
> +
> realm = kzalloc(sizeof(*realm), GFP_NOFS);
> if (!realm)
> return ERR_PTR(-ENOMEM);
> @@ -143,6 +147,8 @@ static struct ceph_snap_realm *__lookup_snap_realm(struct ceph_mds_client *mdsc,
> struct rb_node *n = mdsc->snap_realms.rb_node;
> struct ceph_snap_realm *r;
>
> + lockdep_assert_held_write(&mdsc->snap_rwsem);
> +
> while (n) {
> r = rb_entry(n, struct ceph_snap_realm, node);
> if (ino < r->ino)
> @@ -176,6 +182,8 @@ static void __put_snap_realm(struct ceph_mds_client *mdsc,
> static void __destroy_snap_realm(struct ceph_mds_client *mdsc,
> struct ceph_snap_realm *realm)
> {
> + lockdep_assert_held_write(&mdsc->snap_rwsem);
> +
> dout("__destroy_snap_realm %p %llx\n", realm, realm->ino);
>
> rb_erase(&realm->node, &mdsc->snap_realms);
> @@ -198,6 +206,8 @@ static void __destroy_snap_realm(struct ceph_mds_client *mdsc,
> static void __put_snap_realm(struct ceph_mds_client *mdsc,
> struct ceph_snap_realm *realm)
> {
> + lockdep_assert_held_write(&mdsc->snap_rwsem);
This one appears to be redundant since the only caller is
__destroy_snap_realm().
> +
> dout("__put_snap_realm %llx %p %d -> %d\n", realm->ino, realm,
> atomic_read(&realm->nref), atomic_read(&realm->nref)-1);
> if (atomic_dec_and_test(&realm->nref))
> @@ -236,6 +246,8 @@ static void __cleanup_empty_realms(struct ceph_mds_client *mdsc)
> {
> struct ceph_snap_realm *realm;
>
> + lockdep_assert_held_write(&mdsc->snap_rwsem);
This too since it boils down to calling __destroy_snap_realm().
> +
> spin_lock(&mdsc->snap_empty_lock);
> while (!list_empty(&mdsc->snap_empty)) {
> realm = list_first_entry(&mdsc->snap_empty,
> @@ -269,6 +281,8 @@ static int adjust_snap_realm_parent(struct ceph_mds_client *mdsc,
> {
> struct ceph_snap_realm *parent;
>
> + lockdep_assert_held_write(&mdsc->snap_rwsem);
And this since ceph_lookup_snap_realm() is called right away.
> +
> if (realm->parent_ino == parentino)
> return 0;
>
> @@ -696,6 +710,8 @@ int ceph_update_snap_trace(struct ceph_mds_client *mdsc,
> int err = -ENOMEM;
> LIST_HEAD(dirty_realms);
>
> + lockdep_assert_held_write(&mdsc->snap_rwsem);
Ditto.
Thanks,
Ilya
