Re: [PATCH 3/8] accel/ivpu: Stop job_done_thread on suspend

[Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>]

Hi 
On Mon, Nov 13, 2023 at 08:39:42AM +0100, Daniel Vetter wrote:
> This conflicts with the kthread change in 6.7-rc1 6309727ef271
> ("kthread: add kthread_stop_put")
> 
> Please double-check that the conflict resolution I've done in drm-tip
> is correct and then ask drm-misc/accel maintainers to backmerge -rc2
> to bake this in properly. Adding them as fyi.

Can not rebuild drm-tip due to core-to-CI merge problem. However resolution
in drm-rerere commit fa53f5a2888265d883eedb83a943613a410b9fc9 is correct.

Thomas please do the backmarge.

Regards
Stanislaw

> On Sat, 28 Oct 2023 at 18:00, Stanislaw Gruszka
> <stanislaw.gruszka@linux.intel.com> wrote:
> >
> > Stop job_done thread when going to suspend. Use kthread_park() instead
> > of kthread_stop() to avoid memory allocation and potential failure
> > on resume.
> >
> > Use separate function as thread wake up condition. Use spin lock to assure
> > rx_msg_list is properly protected against concurrent access.
> >
> > Reviewed-by: Karol Wachowski <karol.wachowski@linux.intel.com>
> > Signed-off-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
> > ---
> >  drivers/accel/ivpu/ivpu_drv.c |  2 ++
> >  drivers/accel/ivpu/ivpu_ipc.c | 17 +++++++++++++++--
> >  drivers/accel/ivpu/ivpu_job.c | 20 ++++++++++++++++----
> >  drivers/accel/ivpu/ivpu_job.h |  2 ++
> >  4 files changed, 35 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/accel/ivpu/ivpu_drv.c b/drivers/accel/ivpu/ivpu_drv.c
> > index 064cabef41bb..60277ff6af69 100644
> > --- a/drivers/accel/ivpu/ivpu_drv.c
> > +++ b/drivers/accel/ivpu/ivpu_drv.c
> > @@ -378,6 +378,7 @@ int ivpu_boot(struct ivpu_device *vdev)
> >         enable_irq(vdev->irq);
> >         ivpu_hw_irq_enable(vdev);
> >         ivpu_ipc_enable(vdev);
> > +       ivpu_job_done_thread_enable(vdev);
> >         return 0;
> >  }
> >
> > @@ -389,6 +390,7 @@ int ivpu_shutdown(struct ivpu_device *vdev)
> >         disable_irq(vdev->irq);
> >         ivpu_ipc_disable(vdev);
> >         ivpu_mmu_disable(vdev);
> > +       ivpu_job_done_thread_disable(vdev);
> >
> >         ret = ivpu_hw_power_down(vdev);
> >         if (ret)
> > diff --git a/drivers/accel/ivpu/ivpu_ipc.c b/drivers/accel/ivpu/ivpu_ipc.c
> > index d069d1e1f91d..270caef789bf 100644
> > --- a/drivers/accel/ivpu/ivpu_ipc.c
> > +++ b/drivers/accel/ivpu/ivpu_ipc.c
> > @@ -202,6 +202,20 @@ ivpu_ipc_send(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons, struct v
> >         return ret;
> >  }
> >
> > +static int ivpu_ipc_rx_need_wakeup(struct ivpu_ipc_consumer *cons)
> > +{
> > +       int ret = 0;
> > +
> > +       if (IS_KTHREAD())
> > +               ret |= (kthread_should_stop() || kthread_should_park());
> > +
> > +       spin_lock_irq(&cons->rx_msg_lock);
> > +       ret |= !list_empty(&cons->rx_msg_list);
> > +       spin_unlock_irq(&cons->rx_msg_lock);
> > +
> > +       return ret;
> > +}
> > +
> >  int ivpu_ipc_receive(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons,
> >                      struct ivpu_ipc_hdr *ipc_buf,
> >                      struct vpu_jsm_msg *ipc_payload, unsigned long timeout_ms)
> > @@ -211,8 +225,7 @@ int ivpu_ipc_receive(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons,
> >         int wait_ret, ret = 0;
> >
> >         wait_ret = wait_event_interruptible_timeout(cons->rx_msg_wq,
> > -                                                   (IS_KTHREAD() && kthread_should_stop()) ||
> > -                                                   !list_empty(&cons->rx_msg_list),
> > +                                                   ivpu_ipc_rx_need_wakeup(cons),
> >                                                     msecs_to_jiffies(timeout_ms));
> >
> >         if (IS_KTHREAD() && kthread_should_stop())
> > diff --git a/drivers/accel/ivpu/ivpu_job.c b/drivers/accel/ivpu/ivpu_job.c
> > index 6e96c921547d..a245b2d44db7 100644
> > --- a/drivers/accel/ivpu/ivpu_job.c
> > +++ b/drivers/accel/ivpu/ivpu_job.c
> > @@ -590,6 +590,11 @@ static int ivpu_job_done_thread(void *arg)
> >                                 ivpu_pm_schedule_recovery(vdev);
> >                         }
> >                 }
> > +               if (kthread_should_park()) {
> > +                       ivpu_dbg(vdev, JOB, "Parked %s\n", __func__);
> > +                       kthread_parkme();
> > +                       ivpu_dbg(vdev, JOB, "Unparked %s\n", __func__);
> > +               }
> >         }
> >
> >         ivpu_ipc_consumer_del(vdev, &cons);
> > @@ -610,9 +615,6 @@ int ivpu_job_done_thread_init(struct ivpu_device *vdev)
> >                 return -EIO;
> >         }
> >
> > -       get_task_struct(thread);
> > -       wake_up_process(thread);
> > -
> >         vdev->job_done_thread = thread;
> >
> >         return 0;
> > @@ -620,6 +622,16 @@ int ivpu_job_done_thread_init(struct ivpu_device *vdev)
> >
> >  void ivpu_job_done_thread_fini(struct ivpu_device *vdev)
> >  {
> > +       kthread_unpark(vdev->job_done_thread);
> >         kthread_stop(vdev->job_done_thread);
> > -       put_task_struct(vdev->job_done_thread);
> > +}
> > +
> > +void ivpu_job_done_thread_disable(struct ivpu_device *vdev)
> > +{
> > +       kthread_park(vdev->job_done_thread);
> > +}
> > +
> > +void ivpu_job_done_thread_enable(struct ivpu_device *vdev)
> > +{
> > +       kthread_unpark(vdev->job_done_thread);
> >  }
> > diff --git a/drivers/accel/ivpu/ivpu_job.h b/drivers/accel/ivpu/ivpu_job.h
> > index aa1f0b9479b0..a8e914e5affc 100644
> > --- a/drivers/accel/ivpu/ivpu_job.h
> > +++ b/drivers/accel/ivpu/ivpu_job.h
> > @@ -61,6 +61,8 @@ void ivpu_cmdq_reset_all_contexts(struct ivpu_device *vdev);
> >
> >  int ivpu_job_done_thread_init(struct ivpu_device *vdev);
> >  void ivpu_job_done_thread_fini(struct ivpu_device *vdev);
> > +void ivpu_job_done_thread_disable(struct ivpu_device *vdev);
> > +void ivpu_job_done_thread_enable(struct ivpu_device *vdev);
> >
> >  void ivpu_jobs_abort_all(struct ivpu_device *vdev);
> >
> > --
> > 2.25.1
> >
> 
> 
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch