Hi,
Friendly ping. Any comments or objections?
Thanks.
On Mon, May 30, 2022 at 3:50 PM Muchun Song <songmuchun@xxxxxxxxxxxxx> wrote:
>
> This version is rebased on v5.18.
>
> Since the following patchsets applied. All the kernel memory are charged
> with the new APIs of obj_cgroup.
>
> [v17,00/19] The new cgroup slab memory controller [1]
> [v5,0/7] Use obj_cgroup APIs to charge kmem pages [2]
>
> But user memory allocations (LRU pages) pinning memcgs for a long time -
> it exists at a larger scale and is causing recurring problems in the real
> world: page cache doesn't get reclaimed for a long time, or is used by the
> second, third, fourth, ... instance of the same job that was restarted into
> a new cgroup every time. Unreclaimable dying cgroups pile up, waste memory,
> and make page reclaim very inefficient.
>
> We can convert LRU pages and most other raw memcg pins to the objcg direction
> to fix this problem, and then the LRU pages will not pin the memcgs.
>
> This patchset aims to make the LRU pages to drop the reference to memory
> cgroup by using the APIs of obj_cgroup. Finally, we can see that the number
> of the dying cgroups will not increase if we run the following test script.
>
> ```bash
> #!/bin/bash
>
> dd if=/dev/zero of=temp bs=4096 count=1
> cat /proc/cgroups | grep memory
>
> for i in {0..2000}
> do
> mkdir /sys/fs/cgroup/memory/test$i
> echo $$ > /sys/fs/cgroup/memory/test$i/cgroup.procs
> cat temp >> log
> echo $$ > /sys/fs/cgroup/memory/cgroup.procs
> rmdir /sys/fs/cgroup/memory/test$i
> done
>
> cat /proc/cgroups | grep memory
>
> rm -f temp log
> ```
>
> [1] https://lore.kernel.org/linux-mm/20200623015846.1141975-1-guro@xxxxxx/
> [2] https://lore.kernel.org/linux-mm/20210319163821.20704-1-songmuchun@xxxxxxxxxxxxx/
>
> v4: https://lore.kernel.org/all/20220524060551.80037-1-songmuchun@xxxxxxxxxxxxx/
> v3: https://lore.kernel.org/all/20220216115132.52602-1-songmuchun@xxxxxxxxxxxxx/
> v2: https://lore.kernel.org/all/20210916134748.67712-1-songmuchun@xxxxxxxxxxxxx/
> v1: https://lore.kernel.org/all/20210814052519.86679-1-songmuchun@xxxxxxxxxxxxx/
> RFC v4: https://lore.kernel.org/all/20210527093336.14895-1-songmuchun@xxxxxxxxxxxxx/
> RFC v3: https://lore.kernel.org/all/20210421070059.69361-1-songmuchun@xxxxxxxxxxxxx/
> RFC v2: https://lore.kernel.org/all/20210409122959.82264-1-songmuchun@xxxxxxxxxxxxx/
> RFC v1: https://lore.kernel.org/all/20210330101531.82752-1-songmuchun@xxxxxxxxxxxxx/
>
> v5:
> - Lots of improvements from Johannes, Roman and Waiman.
> - Fix lockdep warning reported by kernel test robot.
> - Add two new patches to do code cleanup.
> - Collect Acked-by and Reviewed-by from Johannes and Roman.
> - I didn't replace local_irq_disable/enable() to local_lock/unlock_irq() since
> local_lock/unlock_irq() takes an parameter, it needs more thinking to transform
> it to local_lock. It could be an improvement in the future.
>
> v4:
> - Resend and rebased on v5.18.
>
> v3:
> - Removed the Acked-by tags from Roman since this version is based on
> the folio relevant.
>
> v2:
> - Rename obj_cgroup_release_kmem() to obj_cgroup_release_bytes() and the
> dependencies of CONFIG_MEMCG_KMEM (suggested by Roman, Thanks).
> - Rebase to linux 5.15-rc1.
> - Add a new pacth to cleanup mem_cgroup_kmem_disabled().
>
> v1:
> - Drop RFC tag.
> - Rebase to linux next-20210811.
>
> RFC v4:
> - Collect Acked-by from Roman.
> - Rebase to linux next-20210525.
> - Rename obj_cgroup_release_uncharge() to obj_cgroup_release_kmem().
> - Change the patch 1 title to "prepare objcg API for non-kmem usage".
> - Convert reparent_ops_head to an array in patch 8.
>
> Thanks for Roman's review and suggestions.
>
> RFC v3:
> - Drop the code cleanup and simplification patches. Gather those patches
> into a separate series[1].
> - Rework patch #1 suggested by Johannes.
>
> RFC v2:
> - Collect Acked-by tags by Johannes. Thanks.
> - Rework lruvec_holds_page_lru_lock() suggested by Johannes. Thanks.
> - Fix move_pages_to_lru().
>
> Muchun Song (11):
> mm: memcontrol: remove dead code and comments
> mm: rename unlock_page_lruvec{_irq, _irqrestore} to
> lruvec_unlock{_irq, _irqrestore}
> mm: memcontrol: prepare objcg API for non-kmem usage
> mm: memcontrol: make lruvec lock safe when LRU pages are reparented
> mm: vmscan: rework move_pages_to_lru()
> mm: thp: make split queue lock safe when LRU pages are reparented
> mm: memcontrol: make all the callers of {folio,page}_memcg() safe
> mm: memcontrol: introduce memcg_reparent_ops
> mm: memcontrol: use obj_cgroup APIs to charge the LRU pages
> mm: lru: add VM_BUG_ON_FOLIO to lru maintenance function
> mm: lru: use lruvec lock to serialize memcg changes
>
> fs/buffer.c | 4 +-
> fs/fs-writeback.c | 23 +-
> include/linux/memcontrol.h | 213 +++++++++------
> include/linux/mm_inline.h | 6 +
> include/trace/events/writeback.h | 5 +
> mm/compaction.c | 39 ++-
> mm/huge_memory.c | 153 +++++++++--
> mm/memcontrol.c | 560 +++++++++++++++++++++++++++------------
> mm/migrate.c | 4 +
> mm/mlock.c | 2 +-
> mm/page_io.c | 5 +-
> mm/swap.c | 62 ++---
> mm/vmscan.c | 67 +++--
> 13 files changed, 767 insertions(+), 376 deletions(-)
>
>
> base-commit: 4b0986a3613c92f4ec1bdc7f60ec66fea135991f
> --
> 2.11.0
>
