> 1/ the return value of ldlm_resource_putref() is never
> used, so change it to return 'void'.
> 2/ Move all of the code to run on the last putref to
> __ldlm_resource_putref_final(). This means a lock
> is taken in one function and dropped in another, but
> that isn't too uncommon, and will disappear in a future
> patch.
> Now that the code it together, it becomes apparent that
> we are dropping a ref on the namespace *before* the last
> use. So keep the ref until after.
Reviewed-by: James Simmons <jsimm...@infradead.org>
> Signed-off-by: NeilBrown <ne...@suse.com>
> ---
> drivers/staging/lustre/lustre/include/lustre_dlm.h | 2 +-
> drivers/staging/lustre/lustre/ldlm/ldlm_resource.c | 21
> +++++++++-----------
> 2 files changed, 10 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/staging/lustre/lustre/include/lustre_dlm.h
> b/drivers/staging/lustre/lustre/include/lustre_dlm.h
> index 5a355fbab401..d668d86423a4 100644
> --- a/drivers/staging/lustre/lustre/include/lustre_dlm.h
> +++ b/drivers/staging/lustre/lustre/include/lustre_dlm.h
> @@ -1190,7 +1190,7 @@ struct ldlm_resource *ldlm_resource_get(struct
> ldlm_namespace *ns,
> struct ldlm_resource *parent,
> const struct ldlm_res_id *,
> enum ldlm_type type, int create);
> -int ldlm_resource_putref(struct ldlm_resource *res);
> +void ldlm_resource_putref(struct ldlm_resource *res);
> void ldlm_resource_add_lock(struct ldlm_resource *res,
> struct list_head *head,
> struct ldlm_lock *lock);
> diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
> b/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
> index 4c44603ab6f9..8841a1bb2c0a 100644
> --- a/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
> +++ b/drivers/staging/lustre/lustre/ldlm/ldlm_resource.c
> @@ -1195,6 +1195,7 @@ static void __ldlm_resource_putref_final(struct
> cfs_hash_bd *bd,
> struct ldlm_resource *res)
> {
> struct ldlm_ns_bucket *nsb = res->lr_ns_bucket;
> + struct ldlm_namespace *ns = nsb->nsb_namespace;
>
> if (!list_empty(&res->lr_granted)) {
> ldlm_resource_dump(D_ERROR, res);
> @@ -1206,15 +1207,18 @@ static void __ldlm_resource_putref_final(struct
> cfs_hash_bd *bd,
> LBUG();
> }
>
> - cfs_hash_bd_del_locked(nsb->nsb_namespace->ns_rs_hash,
> + cfs_hash_bd_del_locked(ns->ns_rs_hash,
> bd, &res->lr_hash);
> lu_ref_fini(&res->lr_reference);
> + cfs_hash_bd_unlock(ns->ns_rs_hash, bd, 1);
> + if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
> + ns->ns_lvbo->lvbo_free(res);
> if (cfs_hash_bd_count_get(bd) == 0)
> - ldlm_namespace_put(nsb->nsb_namespace);
> + ldlm_namespace_put(ns);
> + kmem_cache_free(ldlm_resource_slab, res);
> }
>
> -/* Returns 1 if the resource was freed, 0 if it remains. */
> -int ldlm_resource_putref(struct ldlm_resource *res)
> +void ldlm_resource_putref(struct ldlm_resource *res)
> {
> struct ldlm_namespace *ns = ldlm_res_to_ns(res);
> struct cfs_hash_bd bd;
> @@ -1224,15 +1228,8 @@ int ldlm_resource_putref(struct ldlm_resource *res)
> res, atomic_read(&res->lr_refcount) - 1);
>
> cfs_hash_bd_get(ns->ns_rs_hash, &res->lr_name, &bd);
> - if (cfs_hash_bd_dec_and_lock(ns->ns_rs_hash, &bd, &res->lr_refcount)) {
> + if (cfs_hash_bd_dec_and_lock(ns->ns_rs_hash, &bd, &res->lr_refcount))
> __ldlm_resource_putref_final(&bd, res);
> - cfs_hash_bd_unlock(ns->ns_rs_hash, &bd, 1);
> - if (ns->ns_lvbo && ns->ns_lvbo->lvbo_free)
> - ns->ns_lvbo->lvbo_free(res);
> - kmem_cache_free(ldlm_resource_slab, res);
> - return 1;
> - }
> - return 0;
> }
> EXPORT_SYMBOL(ldlm_resource_putref);
>
>
>
>
