Re: [PATCH 1/9 v3] drm/i915: Move struct_mutex to drm_i915_private

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Fri, Aug 15, 2025 at 09:04:34AM -0400, Rodrigo Vivi wrote:
> On Wed, Aug 13, 2025 at 10:50:25AM -0300, Luiz Otavio Mello wrote:
> > Move legacy BKL struct_mutex from drm_device to drm_i915_private, which
> > is the last remaining user.
> > 
> > Signed-off-by: Luiz Otavio Mello <luiz.mello@estudante.ufscar.br>
> > Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > ---
> >  drivers/gpu/drm/drm_drv.c                  |  2 --
> >  drivers/gpu/drm/i915/gt/uc/intel_guc_log.c |  4 ++--
> >  drivers/gpu/drm/i915/i915_driver.c         |  2 ++
> >  drivers/gpu/drm/i915/i915_drv.h            | 11 +++++++++++
> >  drivers/gpu/drm/i915/i915_irq.c            |  4 ++--
> >  include/drm/drm_device.h                   | 10 ----------
> 
> drm, drm-misc maintainers, ack to merge this through drm-intel-next?

Thomas, I'm sorry but I had forgotten to cc you in this patch as well.

is your ack for the patch 9 also valid in this patch 1?

> 
> >  6 files changed, 17 insertions(+), 16 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/drm_drv.c b/drivers/gpu/drm/drm_drv.c
> > index cdd591b11488..ad3aee354ba3 100644
> > --- a/drivers/gpu/drm/drm_drv.c
> > +++ b/drivers/gpu/drm/drm_drv.c
> > @@ -694,7 +694,6 @@ static void drm_dev_init_release(struct drm_device *dev, void *res)
> >  	mutex_destroy(&dev->master_mutex);
> >  	mutex_destroy(&dev->clientlist_mutex);
> >  	mutex_destroy(&dev->filelist_mutex);
> > -	mutex_destroy(&dev->struct_mutex);
> >  }
> >  
> >  static int drm_dev_init(struct drm_device *dev,
> > @@ -735,7 +734,6 @@ static int drm_dev_init(struct drm_device *dev,
> >  	INIT_LIST_HEAD(&dev->vblank_event_list);
> >  
> >  	spin_lock_init(&dev->event_lock);
> > -	mutex_init(&dev->struct_mutex);
> >  	mutex_init(&dev->filelist_mutex);
> >  	mutex_init(&dev->clientlist_mutex);
> >  	mutex_init(&dev->master_mutex);
> > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c
> > index 09a64f224c49..65ffcaeee4b9 100644
> > --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c
> > +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c
> > @@ -677,7 +677,7 @@ int intel_guc_log_set_level(struct intel_guc_log *log, u32 level)
> >  	if (level < GUC_LOG_LEVEL_DISABLED || level > GUC_LOG_LEVEL_MAX)
> >  		return -EINVAL;
> >  
> > -	mutex_lock(&i915->drm.struct_mutex);
> > +	mutex_lock(&i915->struct_mutex);
> >  
> >  	if (log->level == level)
> >  		goto out_unlock;
> > @@ -695,7 +695,7 @@ int intel_guc_log_set_level(struct intel_guc_log *log, u32 level)
> >  	log->level = level;
> >  
> >  out_unlock:
> > -	mutex_unlock(&i915->drm.struct_mutex);
> > +	mutex_unlock(&i915->struct_mutex);
> >  
> >  	return ret;
> >  }
> > diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
> > index c6263c6d3384..d1559fd8ad3d 100644
> > --- a/drivers/gpu/drm/i915/i915_driver.c
> > +++ b/drivers/gpu/drm/i915/i915_driver.c
> > @@ -233,6 +233,7 @@ static int i915_driver_early_probe(struct drm_i915_private *dev_priv)
> >  
> >  	intel_sbi_init(display);
> >  	vlv_iosf_sb_init(dev_priv);
> > +	mutex_init(&dev_priv->struct_mutex);
> >  	mutex_init(&dev_priv->sb_lock);
> >  
> >  	i915_memcpy_init_early(dev_priv);
> > @@ -291,6 +292,7 @@ static void i915_driver_late_release(struct drm_i915_private *dev_priv)
> >  	i915_workqueues_cleanup(dev_priv);
> >  
> >  	mutex_destroy(&dev_priv->sb_lock);
> > +	mutex_destroy(&dev_priv->struct_mutex);
> >  	vlv_iosf_sb_fini(dev_priv);
> >  	intel_sbi_fini(display);
> >  
> > diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> > index 4e4e89746aa6..15f66a7d496d 100644
> > --- a/drivers/gpu/drm/i915/i915_drv.h
> > +++ b/drivers/gpu/drm/i915/i915_drv.h
> > @@ -222,6 +222,17 @@ struct drm_i915_private {
> >  
> >  	bool irqs_enabled;
> >  
> > +	/*
> > +	 * Currently, struct_mutex is only used by the i915 driver as a replacement
> > +	 * for BKL.
> > +	 *
> > +	 * For this reason, it is no longer part of struct drm_device.
> > +	 */
> > +	struct mutex struct_mutex;
> > +
> > +	/* LPT/WPT IOSF sideband protection */
> > +	struct mutex sbi_lock;
> > +
> >  	/* VLV/CHV IOSF sideband */
> >  	struct {
> >  		struct mutex lock; /* protect sideband access */
> > diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
> > index 191ed8bb1d9c..cdfb09464134 100644
> > --- a/drivers/gpu/drm/i915/i915_irq.c
> > +++ b/drivers/gpu/drm/i915/i915_irq.c
> > @@ -167,7 +167,7 @@ static void ivb_parity_work(struct work_struct *work)
> >  	 * In order to prevent a get/put style interface, acquire struct mutex
> >  	 * any time we access those registers.
> >  	 */
> > -	mutex_lock(&dev_priv->drm.struct_mutex);
> > +	mutex_lock(&dev_priv->struct_mutex);
> >  
> >  	/* If we've screwed up tracking, just let the interrupt fire again */
> >  	if (drm_WARN_ON(&dev_priv->drm, !dev_priv->l3_parity.which_slice))
> > @@ -225,7 +225,7 @@ static void ivb_parity_work(struct work_struct *work)
> >  	gen5_gt_enable_irq(gt, GT_PARITY_ERROR(dev_priv));
> >  	spin_unlock_irq(gt->irq_lock);
> >  
> > -	mutex_unlock(&dev_priv->drm.struct_mutex);
> > +	mutex_unlock(&dev_priv->struct_mutex);
> >  }
> >  
> >  static irqreturn_t valleyview_irq_handler(int irq, void *arg)
> > diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h
> > index a33aedd5e9ec..016df5529d46 100644
> > --- a/include/drm/drm_device.h
> > +++ b/include/drm/drm_device.h
> > @@ -188,16 +188,6 @@ struct drm_device {
> >  	/** @unique: Unique name of the device */
> >  	char *unique;
> >  
> > -	/**
> > -	 * @struct_mutex:
> > -	 *
> > -	 * Lock for others (not &drm_minor.master and &drm_file.is_master)
> > -	 *
> > -	 * TODO: This lock used to be the BKL of the DRM subsystem. Move the
> > -	 *       lock into i915, which is the only remaining user.
> > -	 */
> > -	struct mutex struct_mutex;
> > -
> >  	/**
> >  	 * @master_mutex:
> >  	 *
> > -- 
> > 2.50.1
> >