UPSTREAM: writeback: pass in '0' for nr_pages writeback in laptop mode

Laptop mode really wants to writeback the number of dirty
pages and inodes. Instead of calculating this in the caller,
just pass in 0 and let wakeup_flusher_threads() handle it.

Use the new wakeup_flusher_threads_bdi() instead of rolling
our own.

Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Chris Mason <clm@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
(cherry picked from commit 0ab29fd0accf6e5b6ef5dbe2e0335da6687ce60c)
Signed-off-by: Ke Wu <mikewu@google.com>

BUG=b:136020425
TEST=trybot

Change-Id: Icca1ba3be90cf98b758c3443b4a84e88cb2333db
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/1753426
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Vaibhav Rustagi <vaibhavrustagi@google.com>
Commit-Queue: Ke Wu <mikewu@google.com>
Tested-by: Ke Wu <mikewu@google.com>
1 file changed