f2fs: add core functions for rb-tree extent cache
This patch adds core functions including slab cache init function and
init/lookup/update/shrink/destroy function for rb-tree based extent cache.
Thank Jaegeuk Kim and Changman Lee as they gave much suggestion about detail
design and implementation of extent cache.
Todo:
* register rb-based extent cache shrink with mm shrink interface.
v2:
o move set_extent_info and __is_{extent,back,front}_mergeable into f2fs.h.
o introduce __{attach,detach}_extent_node for code readability.
o add cond_resched() when fail to invoke kmem_cache_alloc/radix_tree_insert.
o fix some coding style and typo issues.
v3:
o fix oops due to using an unassigned pointer.
o use list_del to remove extent node in shrink list.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: add static for some funcitons and declare in f2fs.h]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Chao Yu
Jaegeuk Kim
parent
13054c548a
commit
429511cdf8
3 changed files with 451 additions and 1 deletions
411
fs/f2fs/data.c
411
fs/f2fs/data.c
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@ -25,6 +25,9 @@
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#include "trace.h"
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#include <trace/events/f2fs.h>
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static struct kmem_cache *extent_tree_slab;
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static struct kmem_cache *extent_node_slab;
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static void f2fs_read_end_io(struct bio *bio, int err)
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{
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struct bio_vec *bvec;
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@ -366,6 +369,383 @@ end_update:
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return need_update;
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}
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static struct extent_node *__attach_extent_node(struct f2fs_sb_info *sbi,
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struct extent_tree *et, struct extent_info *ei,
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struct rb_node *parent, struct rb_node **p)
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{
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struct extent_node *en;
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en = kmem_cache_alloc(extent_node_slab, GFP_ATOMIC);
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if (!en)
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return NULL;
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en->ei = *ei;
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INIT_LIST_HEAD(&en->list);
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rb_link_node(&en->rb_node, parent, p);
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rb_insert_color(&en->rb_node, &et->root);
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et->count++;
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atomic_inc(&sbi->total_ext_node);
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return en;
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}
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static void __detach_extent_node(struct f2fs_sb_info *sbi,
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struct extent_tree *et, struct extent_node *en)
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{
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rb_erase(&en->rb_node, &et->root);
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et->count--;
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atomic_dec(&sbi->total_ext_node);
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}
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static struct extent_node *__lookup_extent_tree(struct extent_tree *et,
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unsigned int fofs)
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{
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struct rb_node *node = et->root.rb_node;
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struct extent_node *en;
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while (node) {
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en = rb_entry(node, struct extent_node, rb_node);
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if (fofs < en->ei.fofs)
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node = node->rb_left;
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else if (fofs >= en->ei.fofs + en->ei.len)
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node = node->rb_right;
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else
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return en;
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}
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return NULL;
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}
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static struct extent_node *__try_back_merge(struct f2fs_sb_info *sbi,
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struct extent_tree *et, struct extent_node *en)
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{
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struct extent_node *prev;
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struct rb_node *node;
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node = rb_prev(&en->rb_node);
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if (!node)
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return NULL;
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prev = rb_entry(node, struct extent_node, rb_node);
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if (__is_back_mergeable(&en->ei, &prev->ei)) {
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en->ei.fofs = prev->ei.fofs;
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en->ei.blk = prev->ei.blk;
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en->ei.len += prev->ei.len;
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__detach_extent_node(sbi, et, prev);
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return prev;
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}
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return NULL;
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}
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static struct extent_node *__try_front_merge(struct f2fs_sb_info *sbi,
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struct extent_tree *et, struct extent_node *en)
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{
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struct extent_node *next;
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struct rb_node *node;
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node = rb_next(&en->rb_node);
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if (!node)
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return NULL;
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next = rb_entry(node, struct extent_node, rb_node);
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if (__is_front_mergeable(&en->ei, &next->ei)) {
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en->ei.len += next->ei.len;
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__detach_extent_node(sbi, et, next);
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return next;
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}
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return NULL;
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}
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static struct extent_node *__insert_extent_tree(struct f2fs_sb_info *sbi,
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struct extent_tree *et, struct extent_info *ei,
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struct extent_node **den)
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{
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struct rb_node **p = &et->root.rb_node;
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struct rb_node *parent = NULL;
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struct extent_node *en;
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while (*p) {
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parent = *p;
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en = rb_entry(parent, struct extent_node, rb_node);
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if (ei->fofs < en->ei.fofs) {
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if (__is_front_mergeable(ei, &en->ei)) {
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f2fs_bug_on(sbi, !den);
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en->ei.fofs = ei->fofs;
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en->ei.blk = ei->blk;
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en->ei.len += ei->len;
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*den = __try_back_merge(sbi, et, en);
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return en;
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}
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p = &(*p)->rb_left;
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} else if (ei->fofs >= en->ei.fofs + en->ei.len) {
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if (__is_back_mergeable(ei, &en->ei)) {
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f2fs_bug_on(sbi, !den);
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en->ei.len += ei->len;
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*den = __try_front_merge(sbi, et, en);
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return en;
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}
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p = &(*p)->rb_right;
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} else {
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f2fs_bug_on(sbi, 1);
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}
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}
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return __attach_extent_node(sbi, et, ei, parent, p);
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}
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static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi,
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struct extent_tree *et, bool free_all)
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{
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struct rb_node *node, *next;
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struct extent_node *en;
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unsigned int count = et->count;
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node = rb_first(&et->root);
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while (node) {
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next = rb_next(node);
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en = rb_entry(node, struct extent_node, rb_node);
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if (free_all) {
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spin_lock(&sbi->extent_lock);
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if (!list_empty(&en->list))
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list_del_init(&en->list);
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spin_unlock(&sbi->extent_lock);
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}
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if (free_all || list_empty(&en->list)) {
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__detach_extent_node(sbi, et, en);
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kmem_cache_free(extent_node_slab, en);
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}
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node = next;
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}
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return count - et->count;
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}
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static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs,
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struct extent_info *ei)
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{
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struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
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struct extent_tree *et;
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struct extent_node *en;
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if (is_inode_flag_set(F2FS_I(inode), FI_NO_EXTENT))
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return false;
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down_read(&sbi->extent_tree_lock);
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et = radix_tree_lookup(&sbi->extent_tree_root, inode->i_ino);
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if (!et) {
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up_read(&sbi->extent_tree_lock);
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return false;
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}
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atomic_inc(&et->refcount);
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up_read(&sbi->extent_tree_lock);
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read_lock(&et->lock);
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en = __lookup_extent_tree(et, pgofs);
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if (en) {
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*ei = en->ei;
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spin_lock(&sbi->extent_lock);
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if (!list_empty(&en->list))
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list_move_tail(&en->list, &sbi->extent_list);
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spin_unlock(&sbi->extent_lock);
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stat_inc_read_hit(sbi->sb);
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}
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stat_inc_total_hit(sbi->sb);
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read_unlock(&et->lock);
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atomic_dec(&et->refcount);
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return en ? true : false;
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}
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static void f2fs_update_extent_tree(struct inode *inode, pgoff_t fofs,
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block_t blkaddr)
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{
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struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
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nid_t ino = inode->i_ino;
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struct extent_tree *et;
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struct extent_node *en = NULL, *en1 = NULL, *en2 = NULL, *en3 = NULL;
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struct extent_node *den = NULL;
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struct extent_info ei, dei;
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unsigned int endofs;
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if (is_inode_flag_set(F2FS_I(inode), FI_NO_EXTENT))
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return;
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down_write(&sbi->extent_tree_lock);
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et = radix_tree_lookup(&sbi->extent_tree_root, ino);
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if (!et) {
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et = f2fs_kmem_cache_alloc(extent_tree_slab, GFP_NOFS);
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f2fs_radix_tree_insert(&sbi->extent_tree_root, ino, et);
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memset(et, 0, sizeof(struct extent_tree));
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et->ino = ino;
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et->root = RB_ROOT;
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rwlock_init(&et->lock);
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atomic_set(&et->refcount, 0);
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et->count = 0;
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sbi->total_ext_tree++;
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}
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atomic_inc(&et->refcount);
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up_write(&sbi->extent_tree_lock);
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write_lock(&et->lock);
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/* 1. lookup and remove existing extent info in cache */
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en = __lookup_extent_tree(et, fofs);
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if (!en)
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goto update_extent;
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dei = en->ei;
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__detach_extent_node(sbi, et, en);
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/* 2. if extent can be split more, split and insert the left part */
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if (dei.len > 1) {
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/* insert left part of split extent into cache */
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if (fofs - dei.fofs >= F2FS_MIN_EXTENT_LEN) {
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set_extent_info(&ei, dei.fofs, dei.blk,
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fofs - dei.fofs);
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en1 = __insert_extent_tree(sbi, et, &ei, NULL);
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}
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/* insert right part of split extent into cache */
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endofs = dei.fofs + dei.len - 1;
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if (endofs - fofs >= F2FS_MIN_EXTENT_LEN) {
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set_extent_info(&ei, fofs + 1,
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fofs - dei.fofs + dei.blk, endofs - fofs);
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en2 = __insert_extent_tree(sbi, et, &ei, NULL);
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}
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}
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update_extent:
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/* 3. update extent in extent cache */
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if (blkaddr) {
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set_extent_info(&ei, fofs, blkaddr, 1);
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en3 = __insert_extent_tree(sbi, et, &ei, &den);
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}
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/* 4. update in global extent list */
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spin_lock(&sbi->extent_lock);
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if (en && !list_empty(&en->list))
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list_del(&en->list);
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/*
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* en1 and en2 split from en, they will become more and more smaller
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* fragments after splitting several times. So if the length is smaller
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* than F2FS_MIN_EXTENT_LEN, we will not add them into extent tree.
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*/
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if (en1)
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list_add_tail(&en1->list, &sbi->extent_list);
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if (en2)
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list_add_tail(&en2->list, &sbi->extent_list);
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if (en3) {
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if (list_empty(&en3->list))
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list_add_tail(&en3->list, &sbi->extent_list);
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else
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list_move_tail(&en3->list, &sbi->extent_list);
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}
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if (den && !list_empty(&den->list))
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list_del(&den->list);
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spin_unlock(&sbi->extent_lock);
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/* 5. release extent node */
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if (en)
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kmem_cache_free(extent_node_slab, en);
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if (den)
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kmem_cache_free(extent_node_slab, den);
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write_unlock(&et->lock);
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atomic_dec(&et->refcount);
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}
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void f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
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{
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struct extent_tree *treevec[EXT_TREE_VEC_SIZE];
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struct extent_node *en, *tmp;
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unsigned long ino = F2FS_ROOT_INO(sbi);
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struct radix_tree_iter iter;
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void **slot;
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unsigned int found;
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if (available_free_memory(sbi, EXTENT_CACHE))
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return;
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spin_lock(&sbi->extent_lock);
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list_for_each_entry_safe(en, tmp, &sbi->extent_list, list) {
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if (!nr_shrink--)
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break;
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list_del_init(&en->list);
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}
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spin_unlock(&sbi->extent_lock);
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down_read(&sbi->extent_tree_lock);
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while ((found = radix_tree_gang_lookup(&sbi->extent_tree_root,
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(void **)treevec, ino, EXT_TREE_VEC_SIZE))) {
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unsigned i;
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ino = treevec[found - 1]->ino + 1;
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for (i = 0; i < found; i++) {
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struct extent_tree *et = treevec[i];
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atomic_inc(&et->refcount);
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write_lock(&et->lock);
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__free_extent_tree(sbi, et, false);
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write_unlock(&et->lock);
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atomic_dec(&et->refcount);
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}
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}
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up_read(&sbi->extent_tree_lock);
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down_write(&sbi->extent_tree_lock);
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radix_tree_for_each_slot(slot, &sbi->extent_tree_root, &iter,
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F2FS_ROOT_INO(sbi)) {
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struct extent_tree *et = (struct extent_tree *)*slot;
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if (!atomic_read(&et->refcount) && !et->count) {
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radix_tree_delete(&sbi->extent_tree_root, et->ino);
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kmem_cache_free(extent_tree_slab, et);
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sbi->total_ext_tree--;
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}
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}
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up_write(&sbi->extent_tree_lock);
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}
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void f2fs_destroy_extent_tree(struct inode *inode)
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{
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struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
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struct extent_tree *et;
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down_read(&sbi->extent_tree_lock);
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et = radix_tree_lookup(&sbi->extent_tree_root, inode->i_ino);
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if (!et) {
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up_read(&sbi->extent_tree_lock);
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goto out;
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}
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atomic_inc(&et->refcount);
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up_read(&sbi->extent_tree_lock);
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/* free all extent info belong to this extent tree */
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write_lock(&et->lock);
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__free_extent_tree(sbi, et, true);
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write_unlock(&et->lock);
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atomic_dec(&et->refcount);
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/* try to find and delete extent tree entry in radix tree */
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down_write(&sbi->extent_tree_lock);
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et = radix_tree_lookup(&sbi->extent_tree_root, inode->i_ino);
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if (!et) {
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up_write(&sbi->extent_tree_lock);
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goto out;
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}
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f2fs_bug_on(sbi, atomic_read(&et->refcount) || et->count);
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radix_tree_delete(&sbi->extent_tree_root, inode->i_ino);
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kmem_cache_free(extent_tree_slab, et);
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sbi->total_ext_tree--;
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up_write(&sbi->extent_tree_lock);
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out:
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return;
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}
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static bool f2fs_lookup_extent_cache(struct inode *inode, pgoff_t pgofs,
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struct extent_info *ei)
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{
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@ -1256,6 +1636,37 @@ static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
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return generic_block_bmap(mapping, block, get_data_block);
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}
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void init_extent_cache_info(struct f2fs_sb_info *sbi)
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{
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INIT_RADIX_TREE(&sbi->extent_tree_root, GFP_NOIO);
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init_rwsem(&sbi->extent_tree_lock);
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INIT_LIST_HEAD(&sbi->extent_list);
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spin_lock_init(&sbi->extent_lock);
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sbi->total_ext_tree = 0;
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atomic_set(&sbi->total_ext_node, 0);
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}
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int __init create_extent_cache(void)
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{
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extent_tree_slab = f2fs_kmem_cache_create("f2fs_extent_tree",
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sizeof(struct extent_tree));
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if (!extent_tree_slab)
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return -ENOMEM;
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extent_node_slab = f2fs_kmem_cache_create("f2fs_extent_node",
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sizeof(struct extent_node));
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if (!extent_node_slab) {
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kmem_cache_destroy(extent_tree_slab);
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return -ENOMEM;
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}
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return 0;
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}
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void destroy_extent_cache(void)
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{
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kmem_cache_destroy(extent_node_slab);
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kmem_cache_destroy(extent_tree_slab);
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}
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const struct address_space_operations f2fs_dblock_aops = {
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.readpage = f2fs_read_data_page,
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.readpages = f2fs_read_data_pages,
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@ -352,6 +352,33 @@ static inline void set_raw_extent(struct extent_info *ext,
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|||
i_ext->len = cpu_to_le32(ext->len);
|
||||
}
|
||||
|
||||
static inline void set_extent_info(struct extent_info *ei, unsigned int fofs,
|
||||
u32 blk, unsigned int len)
|
||||
{
|
||||
ei->fofs = fofs;
|
||||
ei->blk = blk;
|
||||
ei->len = len;
|
||||
}
|
||||
|
||||
static inline bool __is_extent_mergeable(struct extent_info *back,
|
||||
struct extent_info *front)
|
||||
{
|
||||
return (back->fofs + back->len == front->fofs &&
|
||||
back->blk + back->len == front->blk);
|
||||
}
|
||||
|
||||
static inline bool __is_back_mergeable(struct extent_info *cur,
|
||||
struct extent_info *back)
|
||||
{
|
||||
return __is_extent_mergeable(back, cur);
|
||||
}
|
||||
|
||||
static inline bool __is_front_mergeable(struct extent_info *cur,
|
||||
struct extent_info *front)
|
||||
{
|
||||
return __is_extent_mergeable(cur, front);
|
||||
}
|
||||
|
||||
struct f2fs_nm_info {
|
||||
block_t nat_blkaddr; /* base disk address of NAT */
|
||||
nid_t max_nid; /* maximum possible node ids */
|
||||
|
|
@ -1541,12 +1568,17 @@ void f2fs_submit_page_mbio(struct f2fs_sb_info *, struct page *,
|
|||
struct f2fs_io_info *);
|
||||
int reserve_new_block(struct dnode_of_data *);
|
||||
int f2fs_reserve_block(struct dnode_of_data *, pgoff_t);
|
||||
void f2fs_shrink_extent_tree(struct f2fs_sb_info *, int);
|
||||
void f2fs_destroy_extent_tree(struct inode *);
|
||||
void f2fs_update_extent_cache(struct dnode_of_data *);
|
||||
struct page *find_data_page(struct inode *, pgoff_t, bool);
|
||||
struct page *get_lock_data_page(struct inode *, pgoff_t);
|
||||
struct page *get_new_data_page(struct inode *, struct page *, pgoff_t, bool);
|
||||
int do_write_data_page(struct page *, struct f2fs_io_info *);
|
||||
int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *, u64, u64);
|
||||
void init_extent_cache_info(struct f2fs_sb_info *);
|
||||
int __init create_extent_cache(void);
|
||||
void destroy_extent_cache(void);
|
||||
void f2fs_invalidate_page(struct page *, unsigned int, unsigned int);
|
||||
int f2fs_release_page(struct page *, gfp_t);
|
||||
|
||||
|
|
|
|||
|
|
@ -41,7 +41,9 @@ bool available_free_memory(struct f2fs_sb_info *sbi, int type)
|
|||
/* only uses low memory */
|
||||
avail_ram = val.totalram - val.totalhigh;
|
||||
|
||||
/* give 25%, 25%, 50%, 50% memory for each components respectively */
|
||||
/*
|
||||
* give 25%, 25%, 50%, 50%, 50% memory for each components respectively
|
||||
*/
|
||||
if (type == FREE_NIDS) {
|
||||
mem_size = (nm_i->fcnt * sizeof(struct free_nid)) >>
|
||||
PAGE_CACHE_SHIFT;
|
||||
|
|
@ -62,6 +64,11 @@ bool available_free_memory(struct f2fs_sb_info *sbi, int type)
|
|||
mem_size += (sbi->im[i].ino_num *
|
||||
sizeof(struct ino_entry)) >> PAGE_CACHE_SHIFT;
|
||||
res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
|
||||
} else if (type == EXTENT_CACHE) {
|
||||
mem_size = (sbi->total_ext_tree * sizeof(struct extent_tree) +
|
||||
atomic_read(&sbi->total_ext_node) *
|
||||
sizeof(struct extent_node)) >> PAGE_CACHE_SHIFT;
|
||||
res = mem_size < ((avail_ram * nm_i->ram_thresh / 100) >> 1);
|
||||
} else {
|
||||
if (sbi->sb->s_bdi->dirty_exceeded)
|
||||
return false;
|
||||
|
|
|
|||
Loading…
Reference in a new issue