f2fs: optimize __update_nat_bits
Make three modification for __update_nat_bits:
1. Take the codes of dealing the nat with nid 0 out of the loop
Such nat only needs to be dealt with once at beginning.
2. Use " nat_index == 0" instead of " start_nid == 0" to decide if it's the first nat block
It's better that we don't assume @start_nid is the first nid of the nat block it's in.
3. Use " if (nat_blk->entries[i].block_addr != NULL_ADDR)" to explicitly comfirm the value of block_addr
use constant to make sure the codes is right, even if the value of NULL_ADDR changes.
Signed-off-by: Fan li <fanofcode.li@samsung.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 c90e667..a7f6603 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -2421,15 +2421,17 @@
unsigned int nat_index = start_nid / NAT_ENTRY_PER_BLOCK;
struct f2fs_nat_block *nat_blk = page_address(page);
int valid = 0;
- int i;
+ int i = 0;
if (!enabled_nat_bits(sbi, NULL))
return;
- for (i = 0; i < NAT_ENTRY_PER_BLOCK; i++) {
- if (start_nid == 0 && i == 0)
- valid++;
- if (nat_blk->entries[i].block_addr)
+ if (nat_index == 0) {
+ valid = 1;
+ i = 1;
+ }
+ for (; i < NAT_ENTRY_PER_BLOCK; i++) {
+ if (nat_blk->entries[i].block_addr != NULL_ADDR)
valid++;
}
if (valid == 0) {