f2fs: seperate read nat page from nat_tree_lock
This patch seperate nat page read io from nat_tree_lock.
-lock_page
-get_node_info()
-current_nat_addr
...... -> write_checkpoint
-get_meta_page
Because we lock node page, we can make sure no other threads
modify this nid concurrently. So we just obtain current_nat_addr
under nat_tree_lock, node info is always same in both nat pack.
Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index ad54e90..b99e318 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -376,6 +376,7 @@
struct page *page = NULL;
struct f2fs_nat_entry ne;
struct nat_entry *e;
+ pgoff_t index;
int i;
ni->nid = nid;
@@ -401,17 +402,21 @@
node_info_from_raw_nat(ni, &ne);
}
up_read(&curseg->journal_rwsem);
- if (i >= 0)
+ if (i >= 0) {
+ up_read(&nm_i->nat_tree_lock);
goto cache;
+ }
/* Fill node_info from nat page */
- page = get_current_nat_page(sbi, start_nid);
+ index = current_nat_addr(sbi, nid);
+ up_read(&nm_i->nat_tree_lock);
+
+ page = get_meta_page(sbi, index);
nat_blk = (struct f2fs_nat_block *)page_address(page);
ne = nat_blk->entries[nid - start_nid];
node_info_from_raw_nat(ni, &ne);
f2fs_put_page(page, 1);
cache:
- up_read(&nm_i->nat_tree_lock);
/* cache nat entry */
down_write(&nm_i->nat_tree_lock);
cache_nat_entry(sbi, nid, &ne);