Re: [PATCH] Revert "workqueue: remove unused cancel_work()"

[Andrey Grodzovsky <andrey.grodzovsky@xxxxxxx>]

See this patch-set https://www.spinics.net/lists/amd-gfx/msg78514.html, specifically patch
'drm/amdgpu: Switch to delayed work from work_struct.

I will just reiterate here -

We need to be able to do non blocking cancel pending reset works
from within GPU reset. Currently kernel API allows this only
for delayed_work and not for work_struct.

Andrey

 

On 2022-05-19 10:52, Lai Jiangshan wrote:

> On Thu, May 19, 2022 at 9:57 PM Andrey Grodzovsky
> <andrey.grodzovsky@xxxxxxx> wrote:
> > This reverts commit 6417250d3f894e66a68ba1cd93676143f2376a6f
> > and exports the function.
> >
> > We need this funtion in amdgpu driver to fix a bug.
> >       
> Hello,
>
> Could you specify the reason why it is needed in amdgpu driver
> rather than "fix a bug", please.
>
> And there is a typo: "funtion".
>
> And please avoid using "we" in the changelog.  For example, the
> sentence can be changed to:
>
> The amdgpu driver needs this function to cancel a work item
> in blabla context/situation or for blabla reason.
> (I'm not good at Engish, this is just an example of not
> using "we".  No need to use the sentence.)
>
> Thanks
> Lai
>
> > Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@xxxxxxx>
> > ---
> >  include/linux/workqueue.h | 1 +
> >  kernel/workqueue.c        | 9 +++++++++
> >  2 files changed, 10 insertions(+)
> >
> > diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
> > index 7fee9b6cfede..9e41e1226193 100644
> > --- a/include/linux/workqueue.h
> > +++ b/include/linux/workqueue.h
> > @@ -453,6 +453,7 @@ extern int schedule_on_each_cpu(work_func_t func);
> >  int execute_in_process_context(work_func_t fn, struct execute_work *);
> >
> >  extern bool flush_work(struct work_struct *work);
> > +extern bool cancel_work(struct work_struct *work);
> >  extern bool cancel_work_sync(struct work_struct *work);
> >
> >  extern bool flush_delayed_work(struct delayed_work *dwork);
> > diff --git a/kernel/workqueue.c b/kernel/workqueue.c
> > index 613917bbc4e7..f94b596ebffd 100644
> > --- a/kernel/workqueue.c
> > +++ b/kernel/workqueue.c
> > @@ -3267,6 +3267,15 @@ static bool __cancel_work(struct work_struct *work, bool is_dwork)
> >         return ret;
> >  }
> >
> > +/*
> > + * See cancel_delayed_work()
> > + */
> > +bool cancel_work(struct work_struct *work)
> > +{
> > +       return __cancel_work(work, false);
> > +}
> > +EXPORT_SYMBOL(cancel_work);
> > +
> >  /**
> >   * cancel_delayed_work - cancel a delayed work
> >   * @dwork: delayed_work to cancel
> > --
> > 2.25.1
> >
> >       
>