[PATCH 2/3] f2fs: shrink blk plug region

From: Chao Yu
Date: Mon Mar 27 2017 - 06:15:44 EST


Don't use blk plug covering area where there won't be any IOs being issued.

Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
fs/f2fs/segment.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index c1a03b0857f9..57a81f9c8c14 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -848,9 +848,8 @@ static int issue_discard_thread(void *data)
if (kthread_should_stop())
return 0;

- blk_start_plug(&plug);
-
mutex_lock(&dcc->cmd_lock);
+ blk_start_plug(&plug);
list_for_each_entry_safe(dc, tmp, pend_list, list) {
f2fs_bug_on(sbi, dc->state != D_PREP);

@@ -860,6 +859,7 @@ static int issue_discard_thread(void *data)
if (iter++ > DISCARD_ISSUE_RATE)
break;
}
+ blk_finish_plug(&plug);

list_for_each_entry_safe(dc, tmp, wait_list, list) {
if (dc->state == D_DONE)
@@ -867,8 +867,6 @@ static int issue_discard_thread(void *data)
}
mutex_unlock(&dcc->cmd_lock);

- blk_finish_plug(&plug);
-
iter = 0;
congestion_wait(BLK_RW_SYNC, HZ/50);

--
2.8.2.295.g3f1c1d0