f2fs: use sbi->write_mutex for write bios
This patch removes an unnecessary semaphore (i.e., sbi->bio_sem).
There is no reason to use the semaphore when f2fs submits read and write IOs.
Instead, let's use a write mutex and cover the sbi->bio[] by the lock.
Change log from v1:
o split write_mutex suggested by Chao Yu
Chao described,
"All DATA/NODE/META bio buffers in superblock is protected by
'sbi->write_mutex', but each bio buffer area is independent, So we
should split write_mutex to three for DATA/NODE/META."
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index d5043bd..68b8a2b 100644
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -869,9 +869,14 @@
void f2fs_submit_bio(struct f2fs_sb_info *sbi, enum page_type type, bool sync)
{
- down_write(&sbi->bio_sem);
+ enum page_type btype = PAGE_TYPE_OF_BIO(type);
+
+ if (!sbi->bio[btype])
+ return;
+
+ mutex_lock(&sbi->write_mutex[btype]);
do_submit_bio(sbi, type, sync);
- up_write(&sbi->bio_sem);
+ mutex_unlock(&sbi->write_mutex[btype]);
}
static void submit_write_page(struct f2fs_sb_info *sbi, struct page *page,
@@ -882,7 +887,7 @@
verify_block_addr(sbi, blk_addr);
- down_write(&sbi->bio_sem);
+ mutex_lock(&sbi->write_mutex[type]);
inc_page_count(sbi, F2FS_WRITEBACK);
@@ -917,7 +922,7 @@
sbi->last_block_in_bio[type] = blk_addr;
- up_write(&sbi->bio_sem);
+ mutex_unlock(&sbi->write_mutex[type]);
trace_f2fs_submit_write_page(page, blk_addr, type);
}