Re: [External] Re: [PATCH 0/3] Suppress undesirable hung task warnings.

[Julian Sun]

On Mon, Sep 22, 2025 at 9:07 PM Michal Hocko <mhocko@xxxxxxxx> wrote:
>
> On Mon 22-09-25 17:41:43, Julian Sun wrote:
> > As suggested by Andrew Morton in [1], we need a general mechanism
>
> what is the reference?

Sorry, the link is:
https://lore.kernel.org/cgroups/20250917152155.5a8ddb3e4ff813289ea0b4c9@xxxxxxxxxxxxxxxxxxxx/
>
> > that allows the hung task detector to ignore unnecessary hung
> > tasks. This patch set implements this functionality.
> >
> > Patch 1 introduces a PF_DONT_HUNG flag. The hung task detector will
> > ignores all tasks that have the PF_DONT_HUNG flag set.
> >
> > Patch 2 introduces wait_event_no_hung() and wb_wait_for_completion_no_hung(),
> > which enable the hung task detector to ignore hung tasks caused by these
> > wait events.
> >
> > Patch 3 uses wb_wait_for_completion_no_hung() in the final phase of memcg
> > teardown to eliminate the hung task warning.
> >
> > Julian Sun (3):
> >   sched: Introduce a new flag PF_DONT_HUNG.
> >   writeback: Introduce wb_wait_for_completion_no_hung().
> >   memcg: Don't trigger hung task when memcg is releasing.
> >
> >  fs/fs-writeback.c           | 15 +++++++++++++++
> >  include/linux/backing-dev.h |  1 +
> >  include/linux/sched.h       | 12 +++++++++++-
> >  include/linux/wait.h        | 15 +++++++++++++++
> >  kernel/hung_task.c          |  6 ++++++
> >  mm/memcontrol.c             |  2 +-
> >  6 files changed, 49 insertions(+), 2 deletions(-)
> >
> > --
> > 2.39.5
>
> --
> Michal Hocko
> SUSE Labs


Thanks,
-- 
Julian Sun <sunjunchao@xxxxxxxxxxxxx>