tree 07361aff698f6fe1cd6b1dcad2ae9ee340b82cb2
parent a83a52c4e201c7afc521c32233f6d2ee7a135db6
author Yunlei He <heyunlei@huawei.com> 1456200476 +0800
committer chrmhoffmann <chrmhoffmann@gmail.com> 1510607463 +0100

f2fs: avoid hungtask problem caused by losing wake_up

The D state of wait_on_all_pages_writeback should be waken by
function f2fs_write_end_io when all writeback pages have been
succesfully written to device. It's possible that wake_up comes
between get_pages and io_schedule. Maybe in this case it will
lost wake_up and still in D state even if all pages have been
write back to device, and finally, the whole system will be into
the hungtask state.

                if (!get_pages(sbi, F2FS_WRITEBACK))
                         break;
					<---------  wake_up
                io_schedule();

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Biao He <hebiao6@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>