Use find_next_bit_le rather than test_bit_le to improve search speed
lightly.
Signed-off-by: Gu Zheng <guz.f...@cn.fujitsu.com>
---
fs/f2fs/dir.c | 43 +++++++++++++++++++++----------------------
1 files changed, 21 insertions(+), 22 deletions(-)
diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 3edd561..ba510fb 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -93,42 +93,41 @@ static struct f2fs_dir_entry *find_in_block(struct page
*dentry_page,
const char *name, size_t namelen, int *max_slots,
f2fs_hash_t namehash, struct page **res_page)
{
- struct f2fs_dir_entry *de;
- unsigned long bit_pos = 0;
+ unsigned long bit_pos = 0, bit_start = 0;
struct f2fs_dentry_block *dentry_blk = kmap(dentry_page);
const void *dentry_bits = &dentry_blk->dentry_bitmap;
- int max_len = 0;
- while (bit_pos < NR_DENTRY_IN_BLOCK) {
- if (!test_bit_le(bit_pos, dentry_bits)) {
- if (bit_pos == 0)
- max_len = 1;
- else if (!test_bit_le(bit_pos - 1, dentry_bits))
- max_len++;
- bit_pos++;
- continue;
+ while (bit_start < NR_DENTRY_IN_BLOCK) {
+ struct f2fs_dir_entry *de;
+ int max_len = 0;
+
+ bit_pos = find_next_bit_le(dentry_bits,
+ NR_DENTRY_IN_BLOCK, bit_start);
+
+ max_len = bit_pos - bit_start;
+ if (max_len > *max_slots) {
+ *max_slots = max_len;
+ max_len = 0;
}
+
+ if (bit_pos >= NR_DENTRY_IN_BLOCK)
+ break;
+
de = &dentry_blk->dentry[bit_pos];
if (early_match_name(name, namelen, namehash, de)) {
if (!memcmp(dentry_blk->filename[bit_pos],
name, namelen)) {
*res_page = dentry_page;
- goto found;
+ return de;
}
}
- if (max_len > *max_slots) {
- *max_slots = max_len;
- max_len = 0;
- }
- bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
+
+ bit_start = bit_pos
+ + GET_DENTRY_SLOTS(le16_to_cpu(de->name_len));
}
- de = NULL;
kunmap(dentry_page);
-found:
- if (max_len > *max_slots)
- *max_slots = max_len;
- return de;
+ return NULL;
}
static struct f2fs_dir_entry *find_in_level(struct inode *dir,
--
1.7.7
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