Re: [Intel-gfx] [PATCH v4 04/11] drm/fb-helper: Push down modeset lock into FB helpers

[Daniel Vetter]

On Wed, Mar 29, 2017 at 04:43:54PM +0200, Thierry Reding wrote:
> From: Thierry Reding 
> 
> Move the modeset locking from drivers into FB helpers.
> 
> Tested-by: John Stultz 
> Reviewed-by: Daniel Vetter 
> Signed-off-by: Thierry Reding 
> ---
>  drivers/gpu/drm/drm_fb_helper.c| 40 
> +-
>  drivers/gpu/drm/i915/intel_dp_mst.c|  3 ---
>  drivers/gpu/drm/radeon/radeon_dp_mst.c |  7 --
>  3 files changed, 34 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
> index 673a47445d61..18105cbe9810 100644
> --- a/drivers/gpu/drm/drm_fb_helper.c
> +++ b/drivers/gpu/drm/drm_fb_helper.c
> @@ -109,8 +109,8 @@ static DEFINE_MUTEX(kernel_fb_helper_lock);
>   for (({ lockdep_assert_held(&(fbh)->dev->mode_config.mutex); }), \
>i__ = 0; i__ < (fbh)->connector_count; i__++)
>  
> -int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
> - struct drm_connector *connector)
> +static int __drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
> +  struct drm_connector *connector)
>  {
>   struct drm_fb_helper_connector *fb_conn;
>   struct drm_fb_helper_connector **temp;
> @@ -141,8 +141,23 @@ int drm_fb_helper_add_one_connector(struct drm_fb_helper 
> *fb_helper,
>   drm_connector_get(connector);
>   fb_conn->connector = connector;
>   fb_helper->connector_info[fb_helper->connector_count++] = fb_conn;
> +
>   return 0;
>  }
> +
> +int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
> + struct drm_connector *connector)
> +{
> + int err;
> +
> + mutex_lock(_helper->dev->mode_config.mutex);
> +
> + err = __drm_fb_helper_add_one_connector(fb_helper, connector);
> +
> + mutex_unlock(_helper->dev->mode_config.mutex);
> +
> + return err;
> +}
>  EXPORT_SYMBOL(drm_fb_helper_add_one_connector);
>  
>  /**
> @@ -172,8 +187,7 @@ int drm_fb_helper_single_add_all_connectors(struct 
> drm_fb_helper *fb_helper)
>   mutex_lock(>mode_config.mutex);
>   drm_connector_list_iter_begin(dev, _iter);
>   drm_for_each_connector_iter(connector, _iter) {
> - ret = drm_fb_helper_add_one_connector(fb_helper, connector);
> -
> + ret = __drm_fb_helper_add_one_connector(fb_helper, connector);
>   if (ret)
>   goto fail;
>   }
> @@ -198,8 +212,8 @@ int drm_fb_helper_single_add_all_connectors(struct 
> drm_fb_helper *fb_helper)
>  }
>  EXPORT_SYMBOL(drm_fb_helper_single_add_all_connectors);
>  
> -int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
> -struct drm_connector *connector)
> +static int __drm_fb_helper_remove_one_connector(struct drm_fb_helper 
> *fb_helper,
> + struct drm_connector *connector)
>  {
>   struct drm_fb_helper_connector *fb_helper_connector;
>   int i, j;
> @@ -227,6 +241,20 @@ int drm_fb_helper_remove_one_connector(struct 
> drm_fb_helper *fb_helper,
>  
>   return 0;
>  }
> +
> +int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
> +struct drm_connector *connector)
> +{
> + int err;
> +
> + mutex_lock(_helper->dev->mode_config.mutex);
> +
> + err = __drm_fb_helper_remove_one_connector(fb_helper, connector);
> +
> + mutex_unlock(_helper->dev->mode_config.mutex);
> +
> + return err;
> +}
>  EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
>  
>  static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct 
> drm_fb_helper *helper)
> diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c 
> b/drivers/gpu/drm/i915/intel_dp_mst.c
> index c1f62eb07c07..1e3ee32a9acb 100644
> --- a/drivers/gpu/drm/i915/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/intel_dp_mst.c
> @@ -484,15 +484,12 @@ static void intel_dp_destroy_mst_connector(struct 
> drm_dp_mst_topology_mgr *mgr,
>  struct drm_connector *connector)
>  {
>   struct intel_connector *intel_connector = to_intel_connector(connector);
> - struct drm_device *dev = connector->dev;
>  
>   drm_connector_unregister(connector);
>  
>   /* need to nuke the connector */
> - drm_modeset_lock_all(dev);
>   intel_connector_remove_from_fbdev(intel_connector);
>   intel_connector->mst_port = NULL;
> - drm_modeset_unlock_all(dev);

I missed that you missed the add_to_fbdev case :( I merged the first 3
patches to drm-misc.

Thanks, Daniel

>  
>   drm_connector_unreference(_connector->base);
>   DRM_DEBUG_KMS("\n");
> diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c 
> b/drivers/gpu/drm/radeon/radeon_dp_mst.c
> index 6598306dca9b..ebdf1b859cb6 100644
> --- 

[Intel-gfx] [PATCH v4 04/11] drm/fb-helper: Push down modeset lock into FB helpers

[Thierry Reding]

From: Thierry Reding 

Move the modeset locking from drivers into FB helpers.

Tested-by: John Stultz 
Reviewed-by: Daniel Vetter 
Signed-off-by: Thierry Reding 
---
 drivers/gpu/drm/drm_fb_helper.c| 40 +-
 drivers/gpu/drm/i915/intel_dp_mst.c|  3 ---
 drivers/gpu/drm/radeon/radeon_dp_mst.c |  7 --
 3 files changed, 34 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 673a47445d61..18105cbe9810 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -109,8 +109,8 @@ static DEFINE_MUTEX(kernel_fb_helper_lock);
for (({ lockdep_assert_held(&(fbh)->dev->mode_config.mutex); }), \
 i__ = 0; i__ < (fbh)->connector_count; i__++)
 
-int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
-   struct drm_connector *connector)
+static int __drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
+struct drm_connector *connector)
 {
struct drm_fb_helper_connector *fb_conn;
struct drm_fb_helper_connector **temp;
@@ -141,8 +141,23 @@ int drm_fb_helper_add_one_connector(struct drm_fb_helper 
*fb_helper,
drm_connector_get(connector);
fb_conn->connector = connector;
fb_helper->connector_info[fb_helper->connector_count++] = fb_conn;
+
return 0;
 }
+
+int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper,
+   struct drm_connector *connector)
+{
+   int err;
+
+   mutex_lock(_helper->dev->mode_config.mutex);
+
+   err = __drm_fb_helper_add_one_connector(fb_helper, connector);
+
+   mutex_unlock(_helper->dev->mode_config.mutex);
+
+   return err;
+}
 EXPORT_SYMBOL(drm_fb_helper_add_one_connector);
 
 /**
@@ -172,8 +187,7 @@ int drm_fb_helper_single_add_all_connectors(struct 
drm_fb_helper *fb_helper)
mutex_lock(>mode_config.mutex);
drm_connector_list_iter_begin(dev, _iter);
drm_for_each_connector_iter(connector, _iter) {
-   ret = drm_fb_helper_add_one_connector(fb_helper, connector);
-
+   ret = __drm_fb_helper_add_one_connector(fb_helper, connector);
if (ret)
goto fail;
}
@@ -198,8 +212,8 @@ int drm_fb_helper_single_add_all_connectors(struct 
drm_fb_helper *fb_helper)
 }
 EXPORT_SYMBOL(drm_fb_helper_single_add_all_connectors);
 
-int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
-  struct drm_connector *connector)
+static int __drm_fb_helper_remove_one_connector(struct drm_fb_helper 
*fb_helper,
+   struct drm_connector *connector)
 {
struct drm_fb_helper_connector *fb_helper_connector;
int i, j;
@@ -227,6 +241,20 @@ int drm_fb_helper_remove_one_connector(struct 
drm_fb_helper *fb_helper,
 
return 0;
 }
+
+int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
+  struct drm_connector *connector)
+{
+   int err;
+
+   mutex_lock(_helper->dev->mode_config.mutex);
+
+   err = __drm_fb_helper_remove_one_connector(fb_helper, connector);
+
+   mutex_unlock(_helper->dev->mode_config.mutex);
+
+   return err;
+}
 EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
 
 static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct 
drm_fb_helper *helper)
diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c 
b/drivers/gpu/drm/i915/intel_dp_mst.c
index c1f62eb07c07..1e3ee32a9acb 100644
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -484,15 +484,12 @@ static void intel_dp_destroy_mst_connector(struct 
drm_dp_mst_topology_mgr *mgr,
   struct drm_connector *connector)
 {
struct intel_connector *intel_connector = to_intel_connector(connector);
-   struct drm_device *dev = connector->dev;
 
drm_connector_unregister(connector);
 
/* need to nuke the connector */
-   drm_modeset_lock_all(dev);
intel_connector_remove_from_fbdev(intel_connector);
intel_connector->mst_port = NULL;
-   drm_modeset_unlock_all(dev);
 
drm_connector_unreference(_connector->base);
DRM_DEBUG_KMS("\n");
diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c 
b/drivers/gpu/drm/radeon/radeon_dp_mst.c
index 6598306dca9b..ebdf1b859cb6 100644
--- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
+++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
@@ -300,9 +300,7 @@ static void radeon_dp_register_mst_connector(struct 
drm_connector *connector)
struct drm_device *dev = connector->dev;
struct radeon_device *rdev = dev->dev_private;
 
-   drm_modeset_lock_all(dev);