Split discard_cmd_list to discard_{pend,wait}_list, so while sending/waiting
discard command, we can avoid traversing unneeded entries in original list.
Signed-off-by: Chao Yu <yuch...@huawei.com>
---
v2: remove unneeded judgment condition in issue_discard_thread.
fs/f2fs/f2fs.h | 3 ++-
fs/f2fs/segment.c | 44 ++++++++++++++++++++++++++------------------
2 files changed, 28 insertions(+), 19 deletions(-)
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 19e28127a725..d3c052f2ad66 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -210,7 +210,8 @@ struct discard_cmd_control {
struct task_struct *f2fs_issue_discard; /* discard thread */
struct list_head discard_entry_list; /* 4KB discard entry list */
int nr_discards; /* # of discards in the list */
- struct list_head discard_cmd_list; /* discard cmd list */
+ struct list_head discard_pend_list; /* store pending entries */
+ struct list_head discard_wait_list; /* store on-flushing entries */
wait_queue_head_t discard_wait_queue; /* waiting queue for wake-up */
struct mutex cmd_lock;
int max_discards; /* max. discards to be issued */
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index 302d2accfe17..6130b3ccd941 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -670,7 +670,7 @@ static void __add_discard_cmd(struct f2fs_sb_info *sbi,
block_t start, block_t len)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
- struct list_head *cmd_list = &(dcc->discard_cmd_list);
+ struct list_head *pend_list = &(dcc->discard_pend_list);
struct discard_cmd *dc;
dc = f2fs_kmem_cache_alloc(discard_cmd_slab, GFP_NOFS);
@@ -684,7 +684,7 @@ static void __add_discard_cmd(struct f2fs_sb_info *sbi,
init_completion(&dc->wait);
mutex_lock(&dcc->cmd_lock);
- list_add_tail(&dc->list, cmd_list);
+ list_add_tail(&dc->list, pend_list);
mutex_unlock(&dcc->cmd_lock);
}
@@ -736,6 +736,7 @@ static void __submit_discard_cmd(struct f2fs_sb_info *sbi,
bio->bi_end_io = f2fs_submit_discard_endio;
bio->bi_opf |= REQ_SYNC;
submit_bio(bio);
+ list_move_tail(&dc->list, &dcc->discard_wait_list);
}
} else {
__remove_discard_cmd(sbi, dc);
@@ -782,31 +783,32 @@ static void __punch_discard_cmd(struct f2fs_sb_info *sbi,
void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, block_t blkaddr)
{
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
- struct list_head *wait_list = &(dcc->discard_cmd_list);
+ struct list_head *pend_list = &(dcc->discard_pend_list);
+ struct list_head *wait_list = &(dcc->discard_wait_list);
struct discard_cmd *dc, *tmp;
struct blk_plug plug;
mutex_lock(&dcc->cmd_lock);
- blk_start_plug(&plug);
-
- list_for_each_entry_safe(dc, tmp, wait_list, list) {
-
- if (blkaddr == NULL_ADDR) {
- __submit_discard_cmd(sbi, dc);
- continue;
- }
+ if (blkaddr == NULL_ADDR)
+ goto release_discard;
+ list_for_each_entry_safe(dc, tmp, pend_list, list) {
if (dc->lstart <= blkaddr && blkaddr < dc->lstart + dc->len) {
if (dc->state == D_SUBMIT)
wait_for_completion_io(&dc->wait);
__punch_discard_cmd(sbi, dc, blkaddr);
}
}
- blk_finish_plug(&plug);
+release_discard:
/* this comes from f2fs_put_super */
if (blkaddr == NULL_ADDR) {
+ blk_start_plug(&plug);
+ list_for_each_entry_safe(dc, tmp, pend_list, list)
+ __submit_discard_cmd(sbi, dc);
+ blk_finish_plug(&plug);
+
list_for_each_entry_safe(dc, tmp, wait_list, list) {
wait_for_completion_io(&dc->wait);
__remove_discard_cmd(sbi, dc);
@@ -820,7 +822,8 @@ static int issue_discard_thread(void *data)
struct f2fs_sb_info *sbi = data;
struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
wait_queue_head_t *q = &dcc->discard_wait_queue;
- struct list_head *cmd_list = &dcc->discard_cmd_list;
+ struct list_head *pend_list = &dcc->discard_pend_list;
+ struct list_head *wait_list = &dcc->discard_wait_list;
struct discard_cmd *dc, *tmp;
struct blk_plug plug;
int iter = 0;
@@ -831,13 +834,17 @@ static int issue_discard_thread(void *data)
blk_start_plug(&plug);
mutex_lock(&dcc->cmd_lock);
- list_for_each_entry_safe(dc, tmp, cmd_list, list) {
+ list_for_each_entry_safe(dc, tmp, pend_list, list) {
+ f2fs_bug_on(sbi, dc->state != D_PREP);
if (is_idle(sbi))
__submit_discard_cmd(sbi, dc);
- if (dc->state == D_PREP && iter++ > DISCARD_ISSUE_RATE)
+ if (iter++ > DISCARD_ISSUE_RATE)
break;
+ }
+
+ list_for_each_entry_safe(dc, tmp, wait_list, list) {
if (dc->state == D_DONE)
__remove_discard_cmd(sbi, dc);
}
@@ -848,8 +855,8 @@ static int issue_discard_thread(void *data)
iter = 0;
congestion_wait(BLK_RW_SYNC, HZ/50);
- wait_event_interruptible(*q,
- kthread_should_stop() || !list_empty(&dcc->discard_cmd_list));
+ wait_event_interruptible(*q, kthread_should_stop() ||
+ !list_empty(pend_list) || !list_empty(wait_list));
goto repeat;
}
@@ -1133,7 +1140,8 @@ static int create_discard_cmd_control(struct f2fs_sb_info
*sbi)
return -ENOMEM;
INIT_LIST_HEAD(&dcc->discard_entry_list);
- INIT_LIST_HEAD(&dcc->discard_cmd_list);
+ INIT_LIST_HEAD(&dcc->discard_pend_list);
+ INIT_LIST_HEAD(&dcc->discard_wait_list);
mutex_init(&dcc->cmd_lock);
atomic_set(&dcc->submit_discard, 0);
dcc->nr_discards = 0;
--
2.8.2.295.g3f1c1d0
