On 2023/7/27 16:04, Qi Zheng wrote:
> In preparation for implementing lockless slab shrink, use new APIs to
> dynamically allocate the xfs-qm shrinker, so that it can be freed
> asynchronously using kfree_rcu(). Then it doesn't need to wait for RCU
> read-side critical section when releasing the struct xfs_quotainfo.
>
> Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
> Reviewed-by: Muchun Song <songmuchun@bytedance.com>
> ---
> fs/xfs/xfs_qm.c | 26 +++++++++++++-------------
> fs/xfs/xfs_qm.h | 2 +-
> 2 files changed, 14 insertions(+), 14 deletions(-)
>
> diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
> index 6abcc34fafd8..032f0a208bd2 100644
> --- a/fs/xfs/xfs_qm.c
> +++ b/fs/xfs/xfs_qm.c
> @@ -504,8 +504,7 @@ xfs_qm_shrink_scan(
> struct shrinker *shrink,
> struct shrink_control *sc)
> {
> - struct xfs_quotainfo *qi = container_of(shrink,
> - struct xfs_quotainfo, qi_shrinker);
> + struct xfs_quotainfo *qi = shrink->private_data;
> struct xfs_qm_isolate isol;
> unsigned long freed;
> int error;
> @@ -539,8 +538,7 @@ xfs_qm_shrink_count(
> struct shrinker *shrink,
> struct shrink_control *sc)
> {
> - struct xfs_quotainfo *qi = container_of(shrink,
> - struct xfs_quotainfo, qi_shrinker);
> + struct xfs_quotainfo *qi = shrink->private_data;
>
> return list_lru_shrink_count(&qi->qi_lru, sc);
> }
> @@ -680,16 +678,18 @@ xfs_qm_init_quotainfo(
> if (XFS_IS_PQUOTA_ON(mp))
> xfs_qm_set_defquota(mp, XFS_DQTYPE_PROJ, qinf);
>
> - qinf->qi_shrinker.count_objects = xfs_qm_shrink_count;
> - qinf->qi_shrinker.scan_objects = xfs_qm_shrink_scan;
> - qinf->qi_shrinker.seeks = DEFAULT_SEEKS;
> - qinf->qi_shrinker.flags = SHRINKER_NUMA_AWARE;
> -
> - error = register_shrinker(&qinf->qi_shrinker, "xfs-qm:%s",
> - mp->m_super->s_id);
> - if (error)
> + qinf->qi_shrinker = shrinker_alloc(SHRINKER_NUMA_AWARE, "xfs-qm:%s",
> + mp->m_super->s_id);
> + if (!qinf->qi_shrinker)
Here should set error to -ENOMEM, will fix.
> goto out_free_inos;
>
> + qinf->qi_shrinker->count_objects = xfs_qm_shrink_count;
> + qinf->qi_shrinker->scan_objects = xfs_qm_shrink_scan;
> + qinf->qi_shrinker->seeks = DEFAULT_SEEKS;
> + qinf->qi_shrinker->private_data = qinf;
> +
> + shrinker_register(qinf->qi_shrinker);
> +
> return 0;
>
> out_free_inos:
> @@ -718,7 +718,7 @@ xfs_qm_destroy_quotainfo(
> qi = mp->m_quotainfo;
> ASSERT(qi != NULL);
>
> - unregister_shrinker(&qi->qi_shrinker);
> + shrinker_free(qi->qi_shrinker);
> list_lru_destroy(&qi->qi_lru);
> xfs_qm_destroy_quotainos(qi);
> mutex_destroy(&qi->qi_tree_lock);
> diff --git a/fs/xfs/xfs_qm.h b/fs/xfs/xfs_qm.h
> index 9683f0457d19..d5c9fc4ba591 100644
> --- a/fs/xfs/xfs_qm.h
> +++ b/fs/xfs/xfs_qm.h
> @@ -63,7 +63,7 @@ struct xfs_quotainfo {
> struct xfs_def_quota qi_usr_default;
> struct xfs_def_quota qi_grp_default;
> struct xfs_def_quota qi_prj_default;
> - struct shrinker qi_shrinker;
> + struct shrinker *qi_shrinker;
>
> /* Minimum and maximum quota expiration timestamp values. */
> time64_t qi_expiry_min;