From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Anholt Subject: [PATCH 2/4] drm/i915: Move the forcewake refcounting to a spinlock. Date: Fri, 3 Jun 2011 12:20:20 -0700 Message-ID: <1307128822-9709-3-git-send-email-eric@anholt.net> References: <1307128822-9709-1-git-send-email-eric@anholt.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1307128822-9709-1-git-send-email-eric@anholt.net> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org We have forcewake in the interrupt handler in the following commit, so we have to use a spinlock instead of a mutex. Signed-off-by: Eric Anholt --- drivers/gpu/drm/i915/i915_debugfs.c | 3 +-- drivers/gpu/drm/i915/i915_dma.c | 1 + drivers/gpu/drm/i915/i915_drv.c | 17 ++++++++++++----- drivers/gpu/drm/i915/i915_drv.h | 3 ++- 4 files changed, 16 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 51c2257..e62ee5d 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -1226,8 +1226,7 @@ static int i915_gen6_forcewake_count_info(struct seq_file *m, void *data) struct drm_device *dev = node->minor->dev; struct drm_i915_private *dev_priv = dev->dev_private; - seq_printf(m, "forcewake count = %d\n", - atomic_read(&dev_priv->forcewake_count)); + seq_printf(m, "forcewake count = %d\n", dev_priv->forcewake_count); return 0; } diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index 0239e99..2de4a74 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -2063,6 +2063,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags) spin_lock_init(&dev_priv->irq_lock); spin_lock_init(&dev_priv->error_lock); spin_lock_init(&dev_priv->rps_lock); + spin_lock_init(&dev_priv->forcewake_lock); if (IS_MOBILE(dev) || !IS_GEN2(dev)) dev_priv->num_pipe = 2; diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 0defd42..0c46bfc 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -319,11 +319,14 @@ static void __gen6_gt_force_wake_get(struct drm_i915_private *dev_priv) */ void gen6_gt_force_wake_get(struct drm_i915_private *dev_priv) { - WARN_ON(!mutex_is_locked(&dev_priv->dev->struct_mutex)); + unsigned long flags; - /* Forcewake is atomic in case we get in here without the lock */ - if (atomic_add_return(1, &dev_priv->forcewake_count) == 1) + spin_lock_irqsave(&dev_priv->forcewake_lock, flags); + + if (dev_priv->forcewake_count++ == 0) __gen6_gt_force_wake_get(dev_priv); + + spin_unlock_irqrestore(&dev_priv->forcewake_lock, flags); } static void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv) @@ -337,10 +340,14 @@ static void __gen6_gt_force_wake_put(struct drm_i915_private *dev_priv) */ void gen6_gt_force_wake_put(struct drm_i915_private *dev_priv) { - WARN_ON(!mutex_is_locked(&dev_priv->dev->struct_mutex)); + unsigned long flags; - if (atomic_dec_and_test(&dev_priv->forcewake_count)) + spin_lock_irqsave(&dev_priv->forcewake_lock, flags); + + if (--dev_priv->forcewake_count == 0) __gen6_gt_force_wake_put(dev_priv); + + spin_unlock_irqrestore(&dev_priv->forcewake_lock, flags); } void __gen6_gt_wait_for_fifo(struct drm_i915_private *dev_priv) diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index ee66035..56ef324 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -717,7 +717,8 @@ typedef struct drm_i915_private { struct drm_property *broadcast_rgb_property; - atomic_t forcewake_count; + int forcewake_count; + spinlock_t forcewake_lock; } drm_i915_private_t; enum i915_cache_level { -- 1.7.5.1