Re: [PATCH 1/7] drm/msm: move wq handling to KMS code

[Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>]

On 14/04/2025 18:58, Rob Clark wrote:
> On Sun, Apr 13, 2025 at 9:33 AM Dmitry Baryshkov
> <dmitry.baryshkov@oss.qualcomm.com> wrote:
>>
>> The global workqueue is only used for vblanks inside KMS code. Move
>> allocation / flushing / deallcation of it to msm_kms.c
> 
> Maybe we should also just move the wq into struct msm_kms?

... together with several other KMS-only fields. I will take a look.

> 
> BR,
> -R
> 
>>
>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
>> ---
>>   drivers/gpu/drm/msm/msm_drv.c | 21 ++-------------------
>>   drivers/gpu/drm/msm/msm_kms.c | 16 +++++++++++++++-
>>   2 files changed, 17 insertions(+), 20 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
>> index c3588dc9e53764a27efda1901b094724cec8928a..02beb40eb9146941aa43862d07a6d82ae21c965e 100644
>> --- a/drivers/gpu/drm/msm/msm_drv.c
>> +++ b/drivers/gpu/drm/msm/msm_drv.c
>> @@ -82,13 +82,6 @@ static int msm_drm_uninit(struct device *dev)
>>                          drm_atomic_helper_shutdown(ddev);
>>          }
>>
>> -       /* We must cancel and cleanup any pending vblank enable/disable
>> -        * work before msm_irq_uninstall() to avoid work re-enabling an
>> -        * irq after uninstall has disabled it.
>> -        */
>> -
>> -       flush_workqueue(priv->wq);
>> -
>>          msm_gem_shrinker_cleanup(ddev);
>>
>>          msm_perf_debugfs_cleanup(priv);
>> @@ -104,8 +97,6 @@ static int msm_drm_uninit(struct device *dev)
>>          ddev->dev_private = NULL;
>>          drm_dev_put(ddev);
>>
>> -       destroy_workqueue(priv->wq);
>> -
>>          return 0;
>>   }
>>
>> @@ -227,12 +218,6 @@ static int msm_drm_init(struct device *dev, const struct drm_driver *drv)
>>          ddev->dev_private = priv;
>>          priv->dev = ddev;
>>
>> -       priv->wq = alloc_ordered_workqueue("msm", 0);
>> -       if (!priv->wq) {
>> -               ret = -ENOMEM;
>> -               goto err_put_dev;
>> -       }
>> -
>>          INIT_LIST_HEAD(&priv->objects);
>>          mutex_init(&priv->obj_lock);
>>
>> @@ -253,12 +238,12 @@ static int msm_drm_init(struct device *dev, const struct drm_driver *drv)
>>          if (priv->kms_init) {
>>                  ret = drmm_mode_config_init(ddev);
>>                  if (ret)
>> -                       goto err_destroy_wq;
>> +                       goto err_put_dev;
>>          }
>>
>>          ret = msm_init_vram(ddev);
>>          if (ret)
>> -               goto err_destroy_wq;
>> +               goto err_put_dev;
>>
>>          dma_set_max_seg_size(dev, UINT_MAX);
>>
>> @@ -304,8 +289,6 @@ static int msm_drm_init(struct device *dev, const struct drm_driver *drv)
>>
>>   err_deinit_vram:
>>          msm_deinit_vram(ddev);
>> -err_destroy_wq:
>> -       destroy_workqueue(priv->wq);
>>   err_put_dev:
>>          drm_dev_put(ddev);
>>
>> diff --git a/drivers/gpu/drm/msm/msm_kms.c b/drivers/gpu/drm/msm/msm_kms.c
>> index 35d5397e73b4c5cb90b1770e8570277e782be7ec..821f0b9f968fc3d448e612bfae04639ceb770353 100644
>> --- a/drivers/gpu/drm/msm/msm_kms.c
>> +++ b/drivers/gpu/drm/msm/msm_kms.c
>> @@ -227,6 +227,13 @@ void msm_drm_kms_uninit(struct device *dev)
>>
>>          BUG_ON(!kms);
>>
>> +       /* We must cancel and cleanup any pending vblank enable/disable
>> +        * work before msm_irq_uninstall() to avoid work re-enabling an
>> +        * irq after uninstall has disabled it.
>> +        */
>> +
>> +       flush_workqueue(priv->wq);
>> +
>>          /* clean up event worker threads */
>>          for (i = 0; i < priv->num_crtcs; i++) {
>>                  if (priv->event_thread[i].worker)
>> @@ -243,6 +250,8 @@ void msm_drm_kms_uninit(struct device *dev)
>>
>>          if (kms && kms->funcs)
>>                  kms->funcs->destroy(kms);
>> +
>> +       destroy_workqueue(priv->wq);
>>   }
>>
>>   int msm_drm_kms_init(struct device *dev, const struct drm_driver *drv)
>> @@ -258,10 +267,14 @@ int msm_drm_kms_init(struct device *dev, const struct drm_driver *drv)
>>          if (ret)
>>                  return ret;
>>
>> +       priv->wq = alloc_ordered_workqueue("msm", 0);
>> +       if (!priv->wq)
>> +               return -ENOMEM;
>> +
>>          ret = priv->kms_init(ddev);
>>          if (ret) {
>>                  DRM_DEV_ERROR(dev, "failed to load kms\n");
>> -               return ret;
>> +               goto err_msm_uninit;
>>          }
>>
>>          /* Enable normalization of plane zpos */
>> @@ -319,6 +332,7 @@ int msm_drm_kms_init(struct device *dev, const struct drm_driver *drv)
>>          return 0;
>>
>>   err_msm_uninit:
>> +       destroy_workqueue(priv->wq);
>>          return ret;
>>   }
>>
>>
>> --
>> 2.39.5
>>


-- 
With best wishes
Dmitry