diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 0c565c941f7a..6e16c1867959 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -888,6 +888,8 @@ struct ext4_inode_info { /* extents status tree */ struct ext4_es_tree i_es_tree; rwlock_t i_es_lock; + struct list_head i_es_lru; + unsigned int i_es_lru_nr; /* protected by i_es_lock */ /* ialloc */ ext4_group_t i_last_alloc_group; @@ -1303,6 +1305,11 @@ struct ext4_sb_info { /* Precomputed FS UUID checksum for seeding other checksums */ __u32 s_csum_seed; + + /* Reclaim extents from extent status tree */ + struct shrinker s_es_shrinker; + struct list_head s_es_lru; + spinlock_t s_es_lru_lock ____cacheline_aligned_in_smp; }; static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb) diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c index cce152c3c8dc..9f1380e05474 100644 --- a/fs/ext4/extents_status.c +++ b/fs/ext4/extents_status.c @@ -145,6 +145,9 @@ static struct kmem_cache *ext4_es_cachep; static int __es_insert_extent(struct inode *inode, struct extent_status *newes); static int __es_remove_extent(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t end); +static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei, + int nr_to_scan); +static int ext4_es_reclaim_extents_count(struct super_block *sb); int __init ext4_init_es(void) { @@ -280,6 +283,7 @@ out: read_unlock(&EXT4_I(inode)->i_es_lock); + ext4_es_lru_add(inode); trace_ext4_es_find_delayed_extent_exit(inode, es); } @@ -294,11 +298,24 @@ ext4_es_alloc_extent(struct inode *inode, ext4_lblk_t lblk, ext4_lblk_t len, es->es_lblk = lblk; es->es_len = len; es->es_pblk = pblk; + + /* + * We don't count delayed extent because we never try to reclaim them + */ + if (!ext4_es_is_delayed(es)) + EXT4_I(inode)->i_es_lru_nr++; + return es; } static void ext4_es_free_extent(struct inode *inode, struct extent_status *es) { + /* Decrease the lru counter when this es is not delayed */ + if (!ext4_es_is_delayed(es)) { + BUG_ON(EXT4_I(inode)->i_es_lru_nr == 0); + EXT4_I(inode)->i_es_lru_nr--; + } + kmem_cache_free(ext4_es_cachep, es); } @@ -456,6 +473,7 @@ int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk, error: write_unlock(&EXT4_I(inode)->i_es_lock); + ext4_es_lru_add(inode); ext4_es_print_tree(inode); return err; @@ -517,6 +535,7 @@ out: read_unlock(&EXT4_I(inode)->i_es_lock); + ext4_es_lru_add(inode); trace_ext4_es_lookup_extent_exit(inode, es, found); return found; } @@ -639,3 +658,140 @@ int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk, ext4_es_print_tree(inode); return err; } + +static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc) +{ + struct ext4_sb_info *sbi = container_of(shrink, + struct ext4_sb_info, s_es_shrinker); + struct ext4_inode_info *ei; + struct list_head *cur, *tmp, scanned; + int nr_to_scan = sc->nr_to_scan; + int ret, nr_shrunk = 0; + + trace_ext4_es_shrink_enter(sbi->s_sb, nr_to_scan); + + if (!nr_to_scan) + return ext4_es_reclaim_extents_count(sbi->s_sb); + + INIT_LIST_HEAD(&scanned); + + spin_lock(&sbi->s_es_lru_lock); + list_for_each_safe(cur, tmp, &sbi->s_es_lru) { + list_move_tail(cur, &scanned); + + ei = list_entry(cur, struct ext4_inode_info, i_es_lru); + + read_lock(&ei->i_es_lock); + if (ei->i_es_lru_nr == 0) { + read_unlock(&ei->i_es_lock); + continue; + } + read_unlock(&ei->i_es_lock); + + write_lock(&ei->i_es_lock); + ret = __es_try_to_reclaim_extents(ei, nr_to_scan); + write_unlock(&ei->i_es_lock); + + nr_shrunk += ret; + nr_to_scan -= ret; + if (nr_to_scan == 0) + break; + } + list_splice_tail(&scanned, &sbi->s_es_lru); + spin_unlock(&sbi->s_es_lru_lock); + trace_ext4_es_shrink_exit(sbi->s_sb, nr_shrunk); + + return ext4_es_reclaim_extents_count(sbi->s_sb); +} + +void ext4_es_register_shrinker(struct super_block *sb) +{ + struct ext4_sb_info *sbi; + + sbi = EXT4_SB(sb); + INIT_LIST_HEAD(&sbi->s_es_lru); + spin_lock_init(&sbi->s_es_lru_lock); + sbi->s_es_shrinker.shrink = ext4_es_shrink; + sbi->s_es_shrinker.seeks = DEFAULT_SEEKS; + register_shrinker(&sbi->s_es_shrinker); +} + +void ext4_es_unregister_shrinker(struct super_block *sb) +{ + unregister_shrinker(&EXT4_SB(sb)->s_es_shrinker); +} + +void ext4_es_lru_add(struct inode *inode) +{ + struct ext4_inode_info *ei = EXT4_I(inode); + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); + + spin_lock(&sbi->s_es_lru_lock); + if (list_empty(&ei->i_es_lru)) + list_add_tail(&ei->i_es_lru, &sbi->s_es_lru); + else + list_move_tail(&ei->i_es_lru, &sbi->s_es_lru); + spin_unlock(&sbi->s_es_lru_lock); +} + +void ext4_es_lru_del(struct inode *inode) +{ + struct ext4_inode_info *ei = EXT4_I(inode); + struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); + + spin_lock(&sbi->s_es_lru_lock); + if (!list_empty(&ei->i_es_lru)) + list_del_init(&ei->i_es_lru); + spin_unlock(&sbi->s_es_lru_lock); +} + +static int ext4_es_reclaim_extents_count(struct super_block *sb) +{ + struct ext4_sb_info *sbi = EXT4_SB(sb); + struct ext4_inode_info *ei; + struct list_head *cur; + int nr_cached = 0; + + spin_lock(&sbi->s_es_lru_lock); + list_for_each(cur, &sbi->s_es_lru) { + ei = list_entry(cur, struct ext4_inode_info, i_es_lru); + read_lock(&ei->i_es_lock); + nr_cached += ei->i_es_lru_nr; + read_unlock(&ei->i_es_lock); + } + spin_unlock(&sbi->s_es_lru_lock); + trace_ext4_es_reclaim_extents_count(sb, nr_cached); + return nr_cached; +} + +static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei, + int nr_to_scan) +{ + struct inode *inode = &ei->vfs_inode; + struct ext4_es_tree *tree = &ei->i_es_tree; + struct rb_node *node; + struct extent_status *es; + int nr_shrunk = 0; + + if (ei->i_es_lru_nr == 0) + return 0; + + node = rb_first(&tree->root); + while (node != NULL) { + es = rb_entry(node, struct extent_status, rb_node); + node = rb_next(&es->rb_node); + /* + * We can't reclaim delayed extent from status tree because + * fiemap, bigallic, and seek_data/hole need to use it. + */ + if (!ext4_es_is_delayed(es)) { + rb_erase(&es->rb_node, &tree->root); + ext4_es_free_extent(inode, es); + nr_shrunk++; + if (--nr_to_scan == 0) + break; + } + } + tree->cache_es = NULL; + return nr_shrunk; +} diff --git a/fs/ext4/extents_status.h b/fs/ext4/extents_status.h index 8ffc90c784fa..cf83e77b16cb 100644 --- a/fs/ext4/extents_status.h +++ b/fs/ext4/extents_status.h @@ -106,4 +106,9 @@ static inline void ext4_es_store_status(struct extent_status *es, es->es_pblk = block; } +extern void ext4_es_register_shrinker(struct super_block *sb); +extern void ext4_es_unregister_shrinker(struct super_block *sb); +extern void ext4_es_lru_add(struct inode *inode); +extern void ext4_es_lru_del(struct inode *inode); + #endif /* _EXT4_EXTENTS_STATUS_H */ diff --git a/fs/ext4/super.c b/fs/ext4/super.c index d80bfe5ac11c..373d46cd5d3f 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -755,6 +755,7 @@ static void ext4_put_super(struct super_block *sb) ext4_abort(sb, "Couldn't clean up the journal"); } + ext4_es_unregister_shrinker(sb); del_timer(&sbi->s_err_report); ext4_release_system_zone(sb); ext4_mb_release(sb); @@ -840,6 +841,8 @@ static struct inode *ext4_alloc_inode(struct super_block *sb) spin_lock_init(&ei->i_prealloc_lock); ext4_es_init_tree(&ei->i_es_tree); rwlock_init(&ei->i_es_lock); + INIT_LIST_HEAD(&ei->i_es_lru); + ei->i_es_lru_nr = 0; ei->i_reserved_data_blocks = 0; ei->i_reserved_meta_blocks = 0; ei->i_allocated_meta_blocks = 0; @@ -928,6 +931,7 @@ void ext4_clear_inode(struct inode *inode) dquot_drop(inode); ext4_discard_preallocations(inode); ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS); + ext4_es_lru_del(inode); if (EXT4_I(inode)->jinode) { jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode), EXT4_I(inode)->jinode); @@ -3693,6 +3697,9 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) sbi->s_max_writeback_mb_bump = 128; sbi->s_extent_max_zeroout_kb = 32; + /* Register extent status tree shrinker */ + ext4_es_register_shrinker(sb); + /* * set up enough so that it can read an inode */ diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h index 1e590b68cec4..c0457c0d1a68 100644 --- a/include/trace/events/ext4.h +++ b/include/trace/events/ext4.h @@ -2255,6 +2255,66 @@ TRACE_EVENT(ext4_es_lookup_extent_exit, __entry->found ? __entry->status : 0) ); +TRACE_EVENT(ext4_es_reclaim_extents_count, + TP_PROTO(struct super_block *sb, int nr_cached), + + TP_ARGS(sb, nr_cached), + + TP_STRUCT__entry( + __field( dev_t, dev ) + __field( int, nr_cached ) + ), + + TP_fast_assign( + __entry->dev = sb->s_dev; + __entry->nr_cached = nr_cached; + ), + + TP_printk("dev %d,%d cached objects nr %d", + MAJOR(__entry->dev), MINOR(__entry->dev), + __entry->nr_cached) +); + +TRACE_EVENT(ext4_es_shrink_enter, + TP_PROTO(struct super_block *sb, int nr_to_scan), + + TP_ARGS(sb, nr_to_scan), + + TP_STRUCT__entry( + __field( dev_t, dev ) + __field( int, nr_to_scan ) + ), + + TP_fast_assign( + __entry->dev = sb->s_dev; + __entry->nr_to_scan = nr_to_scan; + ), + + TP_printk("dev %d,%d nr to scan %d", + MAJOR(__entry->dev), MINOR(__entry->dev), + __entry->nr_to_scan) +); + +TRACE_EVENT(ext4_es_shrink_exit, + TP_PROTO(struct super_block *sb, int shrunk_nr), + + TP_ARGS(sb, shrunk_nr), + + TP_STRUCT__entry( + __field( dev_t, dev ) + __field( int, shrunk_nr ) + ), + + TP_fast_assign( + __entry->dev = sb->s_dev; + __entry->shrunk_nr = shrunk_nr; + ), + + TP_printk("dev %d,%d nr to scan %d", + MAJOR(__entry->dev), MINOR(__entry->dev), + __entry->shrunk_nr) +); + #endif /* _TRACE_EXT4_H */ /* This part must be outside protection */