Only call trace of ext4_mb_check_limits is as following:
ext4_mb_complex_scan_group
ext4_mb_measure_extent
ext4_mb_check_limits(ac, e4b, 0);
ext4_mb_check_limits(ac, e4b, 1);
If the first ac->ac_found > sbi->s_mb_max_to_scan check in
ext4_mb_check_limits is met, we will set ac_status to
AC_STATUS_BREAK and call ext4_mb_try_best_found to try to use
ac->ac_b_ex.
If ext4_mb_try_best_found successes, then block allocation finishs,
the removed ac->ac_found > sbi->s_mb_min_to_scan check is not reachable.
If ext4_mb_try_best_found fails, then we set EXT4_MB_HINT_FIRST and
reset ac->ac_b_ex to retry block allocation. We will use any found
free extent in ext4_mb_measure_extent before reach the removed
ac->ac_found > sbi->s_mb_min_to_scan check.
In summary, the removed ac->ac_found > sbi->s_mb_min_to_scan check is
not reachable and we can remove that dead check.
Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx>
---
fs/ext4/mballoc.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 0fdbf16ac180..e53f84de5018 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -2039,8 +2039,7 @@ static void ext4_mb_check_limits(struct ext4_allocation_context *ac,
if (bex->fe_len < gex->fe_len)
return;
- if ((finish_group || ac->ac_found > sbi->s_mb_min_to_scan)
- && bex->fe_group == e4b->bd_group) {
+ if (finish_group && bex->fe_group == e4b->bd_group) {
/* recheck chunk's availability - we don't know
* when it was found (within this lock-unlock
* period or not) */
--
2.30.0
