f2fs: update comments for explicit memory barrier

Add more detailed comments for explicit memory barrier used by
f2fs, in order to enhance code readability.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit is contained in:
Chao Yu 2021-02-20 17:38:43 +08:00 committed by Jaegeuk Kim
parent 4831675c6b
commit 3b42c741b1
2 changed files with 10 additions and 2 deletions

View file

@ -1818,7 +1818,11 @@ int f2fs_issue_checkpoint(struct f2fs_sb_info *sbi)
llist_add(&req.llnode, &cprc->issue_list);
atomic_inc(&cprc->queued_ckpt);
/* update issue_list before we wake up issue_checkpoint thread */
/*
* update issue_list before we wake up issue_checkpoint thread,
* this smp_mb() pairs with another barrier in ___wait_event(),
* see more details in comments of waitqueue_active().
*/
smp_mb();
if (waitqueue_active(&cprc->ckpt_wait_queue))

View file

@ -653,7 +653,11 @@ int f2fs_issue_flush(struct f2fs_sb_info *sbi, nid_t ino)
llist_add(&cmd.llnode, &fcc->issue_list);
/* update issue_list before we wake up issue_flush thread */
/*
* update issue_list before we wake up issue_flush thread, this
* smp_mb() pairs with another barrier in ___wait_event(), see
* more details in comments of waitqueue_active().
*/
smp_mb();
if (waitqueue_active(&fcc->flush_wait_queue))