From 137d09f002df7d4e52513d75f8910945a6c1bb08 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Thu, 31 Dec 2015 15:02:16 -0800 Subject: f2fs: introduce zombie list for fast shrinking extent trees This patch removes refcount, and instead, adds zombie_list to shrink directly without radix tree traverse. Signed-off-by: Jaegeuk Kim --- fs/f2fs/extent_cache.c | 49 +++++++++++++++++++++---------------------------- fs/f2fs/f2fs.h | 3 ++- 2 files changed, 23 insertions(+), 29 deletions(-) (limited to 'fs') diff --git a/fs/f2fs/extent_cache.c b/fs/f2fs/extent_cache.c index b37184f720e8..4dee2be9a648 100644 --- a/fs/f2fs/extent_cache.c +++ b/fs/f2fs/extent_cache.c @@ -68,13 +68,13 @@ static struct extent_tree *__grab_extent_tree(struct inode *inode) et->root = RB_ROOT; et->cached_en = NULL; rwlock_init(&et->lock); - atomic_set(&et->refcount, 0); + INIT_LIST_HEAD(&et->list); et->count = 0; atomic_inc(&sbi->total_ext_tree); } else { atomic_dec(&sbi->total_zombie_tree); + list_del_init(&et->list); } - atomic_inc(&et->refcount); up_write(&sbi->extent_tree_lock); /* never died until evict_inode */ @@ -551,9 +551,9 @@ static unsigned int f2fs_update_extent_tree_range(struct inode *inode, unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink) { struct extent_tree *treevec[EXT_TREE_VEC_SIZE]; + struct extent_tree *et, *next; struct extent_node *en, *tmp; unsigned long ino = F2FS_ROOT_INO(sbi); - struct radix_tree_root *root = &sbi->extent_tree_root; unsigned int found; unsigned int node_cnt = 0, tree_cnt = 0; int remained; @@ -569,29 +569,20 @@ unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink) goto out; /* 1. remove unreferenced extent tree */ - while ((found = radix_tree_gang_lookup(root, - (void **)treevec, ino, EXT_TREE_VEC_SIZE))) { - unsigned i; - - ino = treevec[found - 1]->ino + 1; - for (i = 0; i < found; i++) { - struct extent_tree *et = treevec[i]; - - if (!atomic_read(&et->refcount)) { - write_lock(&et->lock); - node_cnt += __free_extent_tree(sbi, et, true); - write_unlock(&et->lock); + list_for_each_entry_safe(et, next, &sbi->zombie_list, list) { + write_lock(&et->lock); + node_cnt += __free_extent_tree(sbi, et, true); + write_unlock(&et->lock); - radix_tree_delete(root, et->ino); - kmem_cache_free(extent_tree_slab, et); - atomic_dec(&sbi->total_ext_tree); - atomic_dec(&sbi->total_zombie_tree); - tree_cnt++; + list_del_init(&et->list); + radix_tree_delete(&sbi->extent_tree_root, et->ino); + kmem_cache_free(extent_tree_slab, et); + atomic_dec(&sbi->total_ext_tree); + atomic_dec(&sbi->total_zombie_tree); + tree_cnt++; - if (node_cnt + tree_cnt >= nr_shrink) - goto unlock_out; - } - } + if (node_cnt + tree_cnt >= nr_shrink) + goto unlock_out; } up_write(&sbi->extent_tree_lock); @@ -619,7 +610,7 @@ free_node: */ ino = F2FS_ROOT_INO(sbi); - while ((found = radix_tree_gang_lookup(root, + while ((found = radix_tree_gang_lookup(&sbi->extent_tree_root, (void **)treevec, ino, EXT_TREE_VEC_SIZE))) { unsigned i; @@ -670,8 +661,10 @@ void f2fs_destroy_extent_tree(struct inode *inode) return; if (inode->i_nlink && !is_bad_inode(inode) && et->count) { - atomic_dec(&et->refcount); + down_write(&sbi->extent_tree_lock); + list_add_tail(&et->list, &sbi->zombie_list); atomic_inc(&sbi->total_zombie_tree); + up_write(&sbi->extent_tree_lock); return; } @@ -680,8 +673,7 @@ void f2fs_destroy_extent_tree(struct inode *inode) /* delete extent tree entry in radix tree */ down_write(&sbi->extent_tree_lock); - atomic_dec(&et->refcount); - f2fs_bug_on(sbi, atomic_read(&et->refcount) || et->count); + f2fs_bug_on(sbi, et->count); radix_tree_delete(&sbi->extent_tree_root, inode->i_ino); kmem_cache_free(extent_tree_slab, et); atomic_dec(&sbi->total_ext_tree); @@ -737,6 +729,7 @@ void init_extent_cache_info(struct f2fs_sb_info *sbi) INIT_LIST_HEAD(&sbi->extent_list); spin_lock_init(&sbi->extent_lock); atomic_set(&sbi->total_ext_tree, 0); + INIT_LIST_HEAD(&sbi->zombie_list); atomic_set(&sbi->total_zombie_tree, 0); atomic_set(&sbi->total_ext_node, 0); } diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index d81bf5a43714..e2990c978661 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -359,8 +359,8 @@ struct extent_tree { struct rb_root root; /* root of extent info rb-tree */ struct extent_node *cached_en; /* recently accessed extent node */ struct extent_info largest; /* largested extent info */ + struct list_head list; /* to be used by sbi->zombie_list */ rwlock_t lock; /* protect extent info rb-tree */ - atomic_t refcount; /* reference count of rb-tree */ unsigned int count; /* # of extent node in rb-tree*/ }; @@ -764,6 +764,7 @@ struct f2fs_sb_info { struct list_head extent_list; /* lru list for shrinker */ spinlock_t extent_lock; /* locking extent lru list */ atomic_t total_ext_tree; /* extent tree count */ + struct list_head zombie_list; /* extent zombie tree list */ atomic_t total_zombie_tree; /* extent zombie tree count */ atomic_t total_ext_node; /* extent info count */ -- cgit v1.2.3