[PATCH 0/3] memcg, writeback: Don't wait writeback completion

[Julian Sun <sunjunchao@bytedance.com>]

This patch series aims to eliminate task hangs in mem_cgroup_css_free() 
caused by calling wb_wait_for_completion(). 
This is because there may be a large number of writeback tasks in the 
foreign memcg, involving millions of pages, and the situation is 
exacerbated by WBT rate limiting—potentially leading to task hangs 
lasting several hours.

Patch 1 is preparatory work and involves no functional changes.
Patch 2 implements the automatic release of wb_completion.
Patch 3 removes wb_wait_for_completion() from mem_cgroup_css_free().


Julian Sun (3):
  writeback: Rename wb_writeback_work->auto_free to free_work.
  writeback: Add wb_writeback_work->free_done
  memcg: Don't wait writeback completion when release memcg.

 fs/fs-writeback.c                | 22 ++++++++++++++--------
 include/linux/backing-dev-defs.h |  6 ++++++
 include/linux/memcontrol.h       |  2 +-
 mm/memcontrol.c                  | 29 ++++++++++++++++++++---------
 4 files changed, 41 insertions(+), 18 deletions(-)

-- 
2.20.1