| Message ID | 20230727080502.77895-35-zhengqi.arch@bytedance.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | use refcount+RCU method to implement lockless slab shrink | expand |
On 2023/7/27 16:04, Qi Zheng wrote: > In preparation for implementing lockless slab shrink, use new APIs to > dynamically allocate the ext4-es 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 ext4_sb_info. > > Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com> > Reviewed-by: Muchun Song <songmuchun@bytedance.com> > --- > fs/ext4/ext4.h | 2 +- > fs/ext4/extents_status.c | 22 ++++++++++++---------- > 2 files changed, 13 insertions(+), 11 deletions(-) > > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h > index 1e2259d9967d..82397bf0b33e 100644 > --- a/fs/ext4/ext4.h > +++ b/fs/ext4/ext4.h > @@ -1657,7 +1657,7 @@ struct ext4_sb_info { > __u32 s_csum_seed; > > /* Reclaim extents from extent status tree */ > - struct shrinker s_es_shrinker; > + struct shrinker *s_es_shrinker; > struct list_head s_es_list; /* List of inodes with reclaimable extents */ > long s_es_nr_inode; > struct ext4_es_stats s_es_stats; > diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c > index 9b5b8951afb4..74bb64fadbc4 100644 > --- a/fs/ext4/extents_status.c > +++ b/fs/ext4/extents_status.c > @@ -1596,7 +1596,7 @@ static unsigned long ext4_es_count(struct shrinker *shrink, > unsigned long nr; > struct ext4_sb_info *sbi; > > - sbi = container_of(shrink, struct ext4_sb_info, s_es_shrinker); > + sbi = shrink->private_data; > nr = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_shk_cnt); > trace_ext4_es_shrink_count(sbi->s_sb, sc->nr_to_scan, nr); > return nr; > @@ -1605,8 +1605,7 @@ static unsigned long ext4_es_count(struct shrinker *shrink, > static unsigned long ext4_es_scan(struct shrinker *shrink, > struct shrink_control *sc) > { > - struct ext4_sb_info *sbi = container_of(shrink, > - struct ext4_sb_info, s_es_shrinker); > + struct ext4_sb_info *sbi = shrink->private_data; > int nr_to_scan = sc->nr_to_scan; > int ret, nr_shrunk; > > @@ -1690,14 +1689,17 @@ int ext4_es_register_shrinker(struct ext4_sb_info *sbi) > if (err) > goto err3; > > - sbi->s_es_shrinker.scan_objects = ext4_es_scan; > - sbi->s_es_shrinker.count_objects = ext4_es_count; > - sbi->s_es_shrinker.seeks = DEFAULT_SEEKS; > - err = register_shrinker(&sbi->s_es_shrinker, "ext4-es:%s", > - sbi->s_sb->s_id); > - if (err) > + sbi->s_es_shrinker = shrinker_alloc(0, "ext4-es:%s", sbi->s_sb->s_id); > + if (!sbi->s_es_shrinker) Here should set err to -ENOMEM, will fix. > goto err4; > > + sbi->s_es_shrinker->scan_objects = ext4_es_scan; > + sbi->s_es_shrinker->count_objects = ext4_es_count; > + sbi->s_es_shrinker->seeks = DEFAULT_SEEKS; > + sbi->s_es_shrinker->private_data = sbi; > + > + shrinker_register(sbi->s_es_shrinker); > + > return 0; > err4: > percpu_counter_destroy(&sbi->s_es_stats.es_stats_shk_cnt); > @@ -1716,7 +1718,7 @@ void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi) > percpu_counter_destroy(&sbi->s_es_stats.es_stats_cache_misses); > percpu_counter_destroy(&sbi->s_es_stats.es_stats_all_cnt); > percpu_counter_destroy(&sbi->s_es_stats.es_stats_shk_cnt); > - unregister_shrinker(&sbi->s_es_shrinker); > + shrinker_free(sbi->s_es_shrinker); > } > > /*
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 1e2259d9967d..82397bf0b33e 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1657,7 +1657,7 @@ struct ext4_sb_info { __u32 s_csum_seed; /* Reclaim extents from extent status tree */ - struct shrinker s_es_shrinker; + struct shrinker *s_es_shrinker; struct list_head s_es_list; /* List of inodes with reclaimable extents */ long s_es_nr_inode; struct ext4_es_stats s_es_stats; diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c index 9b5b8951afb4..74bb64fadbc4 100644 --- a/fs/ext4/extents_status.c +++ b/fs/ext4/extents_status.c @@ -1596,7 +1596,7 @@ static unsigned long ext4_es_count(struct shrinker *shrink, unsigned long nr; struct ext4_sb_info *sbi; - sbi = container_of(shrink, struct ext4_sb_info, s_es_shrinker); + sbi = shrink->private_data; nr = percpu_counter_read_positive(&sbi->s_es_stats.es_stats_shk_cnt); trace_ext4_es_shrink_count(sbi->s_sb, sc->nr_to_scan, nr); return nr; @@ -1605,8 +1605,7 @@ static unsigned long ext4_es_count(struct shrinker *shrink, static unsigned long ext4_es_scan(struct shrinker *shrink, struct shrink_control *sc) { - struct ext4_sb_info *sbi = container_of(shrink, - struct ext4_sb_info, s_es_shrinker); + struct ext4_sb_info *sbi = shrink->private_data; int nr_to_scan = sc->nr_to_scan; int ret, nr_shrunk; @@ -1690,14 +1689,17 @@ int ext4_es_register_shrinker(struct ext4_sb_info *sbi) if (err) goto err3; - sbi->s_es_shrinker.scan_objects = ext4_es_scan; - sbi->s_es_shrinker.count_objects = ext4_es_count; - sbi->s_es_shrinker.seeks = DEFAULT_SEEKS; - err = register_shrinker(&sbi->s_es_shrinker, "ext4-es:%s", - sbi->s_sb->s_id); - if (err) + sbi->s_es_shrinker = shrinker_alloc(0, "ext4-es:%s", sbi->s_sb->s_id); + if (!sbi->s_es_shrinker) goto err4; + sbi->s_es_shrinker->scan_objects = ext4_es_scan; + sbi->s_es_shrinker->count_objects = ext4_es_count; + sbi->s_es_shrinker->seeks = DEFAULT_SEEKS; + sbi->s_es_shrinker->private_data = sbi; + + shrinker_register(sbi->s_es_shrinker); + return 0; err4: percpu_counter_destroy(&sbi->s_es_stats.es_stats_shk_cnt); @@ -1716,7 +1718,7 @@ void ext4_es_unregister_shrinker(struct ext4_sb_info *sbi) percpu_counter_destroy(&sbi->s_es_stats.es_stats_cache_misses); percpu_counter_destroy(&sbi->s_es_stats.es_stats_all_cnt); percpu_counter_destroy(&sbi->s_es_stats.es_stats_shk_cnt); - unregister_shrinker(&sbi->s_es_shrinker); + shrinker_free(sbi->s_es_shrinker); } /*