Re: [PATCH v2 06/37] drm/nouveau: move allocation of root client out of nouveau_cli_init()

[Danilo Krummrich <dakr@redhat.com>]

On Fri, Jul 05, 2024 at 04:36:50AM +1000, Ben Skeggs wrote:
> drm->master isn't really a nouveau_cli, and is mostly just used to get
> at an nvif_mmu object to implement a hack around issues with the ioctl
> interface to nvkm.
> 
> Later patches in this series will allocate nvif_device/mmu objects in
> nouveau_drm directly, removing the need for master.

Please don't use future tense.

> 
> Another patch series will remove the need for the above-mentioned hack
> entirely.

Do you have those patches already?

> 
> The only other member of drm->master that's needed is the nvif_client,
> and is a dependency of device/mmu.  So the first step is to move its
> allocation out of code handling nouveau_cli init.
> 
> v2:
> - modified slightly due to the addition of tegra/pci cleanup patches
> 
> Signed-off-by: Ben Skeggs <bskeggs@nvidia.com>
> ---
>  drivers/gpu/drm/nouveau/nouveau_drm.c | 46 ++++++++++++++-------------
>  1 file changed, 24 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/gpu/drm/nouveau/nouveau_drm.c b/drivers/gpu/drm/nouveau/nouveau_drm.c
> index 140e27af0d64..a942d2c03d44 100644
> --- a/drivers/gpu/drm/nouveau/nouveau_drm.c
> +++ b/drivers/gpu/drm/nouveau/nouveau_drm.c
> @@ -129,12 +129,12 @@ nouveau_platform_name(struct platform_device *platformdev)
>  }
>  
>  static u64
> -nouveau_name(struct drm_device *dev)
> +nouveau_name(struct device *dev)
>  {
> -	if (dev_is_pci(dev->dev))
> -		return nouveau_pci_name(to_pci_dev(dev->dev));
> +	if (dev_is_pci(dev))
> +		return nouveau_pci_name(to_pci_dev(dev));
>  	else
> -		return nouveau_platform_name(to_platform_device(dev->dev));
> +		return nouveau_platform_name(to_platform_device(dev));

This looks like it should be a separate patch.

>  }
>  
>  static inline bool
> @@ -209,9 +209,11 @@ nouveau_cli_fini(struct nouveau_cli *cli)
>  	nouveau_vmm_fini(&cli->vmm);
>  	nvif_mmu_dtor(&cli->mmu);
>  	nvif_device_dtor(&cli->device);
> -	mutex_lock(&cli->drm->master.lock);
> -	nvif_client_dtor(&cli->base);
> -	mutex_unlock(&cli->drm->master.lock);
> +	if (cli != &cli->drm->master) {
> +		mutex_lock(&cli->drm->master.lock);
> +		nvif_client_dtor(&cli->base);
> +		mutex_unlock(&cli->drm->master.lock);
> +	}
>  }
>  
>  static int
> @@ -241,7 +243,7 @@ nouveau_cli_init(struct nouveau_drm *drm, const char *sname,
>  		{ NVIF_CLASS_VMM_NV04 , -1 },
>  		{}
>  	};
> -	u64 device = nouveau_name(drm->dev);
> +	u64 device = nouveau_name(drm->dev->dev);
>  	int ret;
>  
>  	snprintf(cli->name, sizeof(cli->name), "%s", sname);
> @@ -253,10 +255,7 @@ nouveau_cli_init(struct nouveau_drm *drm, const char *sname,
>  	INIT_LIST_HEAD(&cli->worker);
>  	mutex_init(&cli->lock);
>  
> -	if (cli == &drm->master) {
> -		ret = nvif_driver_init(NULL, nouveau_config, nouveau_debug,
> -				       cli->name, device, &cli->base);
> -	} else {
> +	if (cli != &drm->master) {
>  		mutex_lock(&drm->master.lock);
>  		ret = nvif_client_ctor(&drm->master.base, cli->name, device,
>  				       &cli->base);
> @@ -626,7 +625,6 @@ nouveau_drm_device_fini(struct nouveau_drm *drm)
>  	nouveau_cli_fini(&drm->client);
>  	nouveau_cli_fini(&drm->master);
>  	destroy_workqueue(drm->sched_wq);
> -	nvif_parent_dtor(&drm->parent);
>  	mutex_destroy(&drm->clients_lock);
>  }
>  
> @@ -636,15 +634,10 @@ nouveau_drm_device_init(struct nouveau_drm *drm)
>  	struct drm_device *dev = drm->dev;
>  	int ret;
>  
> -	nvif_parent_ctor(&nouveau_parent, &drm->parent);
> -	drm->master.base.object.parent = &drm->parent;

Moving this to nouveau_drm_device_new(), plus the resulting changes in error
handling, don't seem to be related to this commit either.

> -
>  	drm->sched_wq = alloc_workqueue("nouveau_sched_wq_shared", 0,
>  					WQ_MAX_ACTIVE);
> -	if (!drm->sched_wq) {
> -		ret = -ENOMEM;
> -		goto fail_alloc;
> -	}
> +	if (!drm->sched_wq)
> +		return -ENOMEM;
>  
>  	ret = nouveau_cli_init(drm, "DRM-master", &drm->master);
>  	if (ret)
> @@ -726,8 +719,6 @@ nouveau_drm_device_init(struct nouveau_drm *drm)
>  	nouveau_cli_fini(&drm->master);
>  fail_wq:
>  	destroy_workqueue(drm->sched_wq);
> -fail_alloc:
> -	nvif_parent_dtor(&drm->parent);
>  	return ret;
>  }
>  
> @@ -737,6 +728,9 @@ nouveau_drm_device_del(struct nouveau_drm *drm)
>  	if (drm->dev)
>  		drm_dev_put(drm->dev);
>  
> +	nvif_client_dtor(&drm->master.base);
> +	nvif_parent_dtor(&drm->parent);
> +
>  	kfree(drm);
>  }
>  
> @@ -753,6 +747,14 @@ nouveau_drm_device_new(const struct drm_driver *drm_driver, struct device *paren
>  
>  	drm->nvkm = device;
>  
> +	nvif_parent_ctor(&nouveau_parent, &drm->parent);
> +	drm->master.base.object.parent = &drm->parent;
> +
> +	ret = nvif_driver_init(NULL, nouveau_config, nouveau_debug, "drm",
> +			       nouveau_name(parent), &drm->master.base);
> +	if (ret)
> +		goto done;
> +
>  	drm->dev = drm_dev_alloc(drm_driver, parent);
>  	if (IS_ERR(drm->dev)) {
>  		ret = PTR_ERR(drm->dev);
> -- 
> 2.45.1
>