Hi All, Is any more comments of this version? Thanks Alex 在 2020/11/5 下午4:55, Alex Shi 写道: > This version rebase on next/master 20201104, with much of Johannes's > Acks and some changes according to Johannes comments. And add a new patch > v21-0006-mm-rmap-stop-store-reordering-issue-on-page-mapp.patch to support > v21-0007. > > This patchset followed 2 memcg VM_WARN_ON_ONCE_PAGE patches which were > added to -mm tree yesterday. > > Many thanks for line by line review by Hugh Dickins, Alexander Duyck and > Johannes Weiner. > > So now this patchset includes 3 parts: > 1, some code cleanup and minimum optimization as a preparation. > 2, use TestCleanPageLRU as page isolation's precondition. > 3, replace per node lru_lock with per memcg per node lru_lock. > > Current lru_lock is one for each of node, pgdat->lru_lock, that guard for > lru lists, but now we had moved the lru lists into memcg for long time. Still > using per node lru_lock is clearly unscalable, pages on each of memcgs have > to compete each others for a whole lru_lock. This patchset try to use per > lruvec/memcg lru_lock to repleace per node lru lock to guard lru lists, make > it scalable for memcgs and get performance gain. > > Currently lru_lock still guards both lru list and page's lru bit, that's ok. > but if we want to use specific lruvec lock on the page, we need to pin down > the page's lruvec/memcg during locking. Just taking lruvec lock first may be > undermined by the page's memcg charge/migration. To fix this problem, we could > take out the page's lru bit clear and use it as pin down action to block the > memcg changes. That's the reason for new atomic func TestClearPageLRU. > So now isolating a page need both actions: TestClearPageLRU and hold the > lru_lock. > > The typical usage of this is isolate_migratepages_block() in compaction.c > we have to take lru bit before lru lock, that serialized the page isolation > in memcg page charge/migration which will change page's lruvec and new > lru_lock in it. > > The above solution suggested by Johannes Weiner, and based on his new memcg > charge path, then have this patchset. (Hugh Dickins tested and contributed much > code from compaction fix to general code polish, thanks a lot!). > > Daniel Jordan's testing show 62% improvement on modified readtwice case > on his 2P * 10 core * 2 HT broadwell box on v18, which has no much different > with this v20. > https://lore.kernel.org/lkml/20200915165807.kpp7uhiw7l3loofu@xxxxxxxxxxxxxxxxxxxxxxxxxx/ > > Thanks Hugh Dickins and Konstantin Khlebnikov, they both brought this > idea 8 years ago, and others who give comments as well: Daniel Jordan, > Mel Gorman, Shakeel Butt, Matthew Wilcox, Alexander Duyck etc. > > Thanks for Testing support from Intel 0day and Rong Chen, Fengguang Wu, > and Yun Wang. Hugh Dickins also shared his kbuild-swap case. Thanks! > > > Alex Shi (16): > mm/thp: move lru_add_page_tail func to huge_memory.c > mm/thp: use head for head page in lru_add_page_tail > mm/thp: Simplify lru_add_page_tail() > mm/thp: narrow lru locking > mm/vmscan: remove unnecessary lruvec adding > mm/rmap: stop store reordering issue on page->mapping > mm/memcg: add debug checking in lock_page_memcg > mm/swap.c: fold vm event PGROTATED into pagevec_move_tail_fn > mm/lru: move lock into lru_note_cost > mm/vmscan: remove lruvec reget in move_pages_to_lru > mm/mlock: remove lru_lock on TestClearPageMlocked > mm/mlock: remove __munlock_isolate_lru_page > mm/lru: introduce TestClearPageLRU > mm/compaction: do page isolation first in compaction > mm/swap.c: serialize memcg changes in pagevec_lru_move_fn > mm/lru: replace pgdat lru_lock with lruvec lock > > Alexander Duyck (1): > mm/lru: introduce the relock_page_lruvec function > > Hugh Dickins (2): > mm: page_idle_get_page() does not need lru_lock > mm/lru: revise the comments of lru_lock > > Documentation/admin-guide/cgroup-v1/memcg_test.rst | 15 +- > Documentation/admin-guide/cgroup-v1/memory.rst | 21 +-- > Documentation/trace/events-kmem.rst | 2 +- > Documentation/vm/unevictable-lru.rst | 22 +-- > include/linux/memcontrol.h | 110 +++++++++++ > include/linux/mm_types.h | 2 +- > include/linux/mmzone.h | 6 +- > include/linux/page-flags.h | 1 + > include/linux/swap.h | 4 +- > mm/compaction.c | 94 +++++++--- > mm/filemap.c | 4 +- > mm/huge_memory.c | 45 +++-- > mm/memcontrol.c | 79 +++++++- > mm/mlock.c | 63 ++----- > mm/mmzone.c | 1 + > mm/page_alloc.c | 1 - > mm/page_idle.c | 4 - > mm/rmap.c | 11 +- > mm/swap.c | 208 ++++++++------------- > mm/vmscan.c | 207 ++++++++++---------- > mm/workingset.c | 2 - > 21 files changed, 530 insertions(+), 372 deletions(-) >
