Re: [PATCH 0/4] mm: replace PF_KCOMPACTD/PF_KSWAPD with kthread_func()

[Shakeel Butt <shakeel.butt@linux.dev>]

On Wed, Sep 02, 2026 at 09:16:49PM +0800, Kefeng Wang wrote:
> The task_struct->flags field is a limited 32-bit resource. Two flag bits,
> PF_KCOMPACTD and PF_KSWAPD, are used to identify whether a kernel thread
> is kcompactd or kswapd. Converting these to use kthread_func() frees up
> two valuable flag bits for future use.

I wouldn't call it a limited resource. We can have more fields in task_struct
but I like the cleanups.

> 
> Kefeng Wang (4):
>   xfs: remove dead kswapd flag inheritance from btree split worker
>   iomap: simplify writepages reclaim guard
>   mm: replace PF_KSWAPD flag with kthread_func() check
>   mm: replace PF_KCOMPACTD flag with kthread_func() check
> 
>  fs/iomap/buffered-io.c                   |  3 +--
>  fs/xfs/libxfs/xfs_btree.c                | 18 +-----------------
>  fs/xfs/xfs_platform.h                    |  4 ----
>  include/linux/compaction.h               | 11 ++++++-----
>  include/linux/sched.h                    |  4 ++--
>  include/linux/swap.h                     |  7 +------
>  mm/compaction.c                          |  9 ++++++---
>  mm/vmscan.c                              | 10 ++++++++--
>  tools/sched_ext/include/scx/common.bpf.h |  2 --
>  9 files changed, 25 insertions(+), 43 deletions(-)
> 
> -- 
> 2.55.0
>