[PATCH v2 0/3] mm/zswap: fix race between lru writeback and swapoff

[Chengming Zhou <zhouchengming@bytedance.com>]

This is based on mm-unstable and the "mm: zswap: fix missing folio cleanup
in writeback race path" patch [1].

Changes in v2:
- Append a patch to remove list_lru_putback() since its only user
  in zswap has gone, per Nhat.
- Improve the commit messages per Johannes.
- Add comments about the lru rotate in shrink_memcg_cb() per Johannes.
- Collect tags.
- Link to v1: https://lore.kernel.org/all/20240126083015.3557006-1-chengming.zhou@linux.dev/

This series mainly fix the race problem between lru writeback and swapoff,
which is spotted by Yosry [2]. Please see the commits for details.

Thanks for review and comments!

[1] https://lore.kernel.org/all/20240125085127.1327013-1-yosryahmed@google.com/
[2] https://lore.kernel.org/all/CAJD7tkasHsRnT_75-TXsEe58V9_OW6m3g6CF7Kmsvz8CKRG_EA@mail.gmail.com/

Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
---
Chengming Zhou (3):
      mm/zswap: don't return LRU_SKIP if we have dropped lru lock
      mm/zswap: fix race between lru writeback and swapoff
      mm/list_lru: remove list_lru_putback()

 include/linux/list_lru.h |  16 -------
 mm/list_lru.c            |  14 ------
 mm/zswap.c               | 120 ++++++++++++++++++++---------------------------
 3 files changed, 51 insertions(+), 99 deletions(-)
---
base-commit: 13d63cb513841433b69564b07614169e61113720
change-id: 20240126-zswap-writeback-race-2773be0a3ad4

Best regards,
-- 
Chengming Zhou <zhouchengming@bytedance.com>