In commit 8648de2c58 ("f2fs: add bio cache for IPU"), we added
f2fs_submit_ipu_bio() in __write_data_page() as below:
__write_data_page()
if (!S_ISDIR(inode->i_mode) && !IS_NOQUOTA(inode)) {
f2fs_submit_ipu_bio(sbi, bio, page);
....
}
in order to avoid below deadlock:
Thread A Thread B
- __write_data_page (inode x, page y)
- f2fs_do_write_data_page
- set_page_writeback ---- set writeback flag in page y
- f2fs_inplace_write_data
- f2fs_balance_fs
- lock gc_mutex
- lock gc_mutex
- f2fs_gc
- do_garbage_collect
- gc_data_segment
- move_data_page
- f2fs_wait_on_page_writeback
- wait_on_page_writeback --- wait writeback of page y
However, the bio submission breaks the merge of IPU IOs.
So in this patch let's add a global bio cache for merged IPU pages,
then f2fs_wait_on_page_writeback() is able to submit bio if a
writebacked page is cached in global bio cache.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
0b20fcec86