From: Daniel Vetter Date: Mon, 15 Sep 2014 12:55:22 +0000 (+0200) Subject: drm/i915: Clarify event_lock locking, process context X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=5e2d7afcfefa7cda3f341ce78523bb9b0acdbacf;p=linux-beck.git drm/i915: Clarify event_lock locking, process context It's good practice to use the more specific versions for irq save spinlocks both as executable documentation and to enforce saner design. The _irqsave version really should only be used if the calling context is unknown and there's a good reason to call a function from all kinds of places. This is the first step whice replaces all occurances of _irqsave in process context with the simpler irq disable/enable variants. We don't have any funky spinlock nesting going on, especially since the event_lock is the outermost of the irq/vblank related spinlocks. Reviewed-by: Jesse Barnes Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 063b44817e08..0ba5c7145240 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -516,7 +516,6 @@ static int i915_gem_pageflip_info(struct seq_file *m, void *data) struct drm_info_node *node = m->private; struct drm_device *dev = node->minor->dev; struct drm_i915_private *dev_priv = dev->dev_private; - unsigned long flags; struct intel_crtc *crtc; int ret; @@ -529,7 +528,7 @@ static int i915_gem_pageflip_info(struct seq_file *m, void *data) const char plane = plane_name(crtc->plane); struct intel_unpin_work *work; - spin_lock_irqsave(&dev->event_lock, flags); + spin_lock_irq(&dev->event_lock); work = crtc->unpin_work; if (work == NULL) { seq_printf(m, "No flip due on pipe %c (plane %c)\n", @@ -575,7 +574,7 @@ static int i915_gem_pageflip_info(struct seq_file *m, void *data) seq_printf(m, "MMIO update completed? %d\n", addr == work->gtt_offset); } } - spin_unlock_irqrestore(&dev->event_lock, flags); + spin_unlock_irq(&dev->event_lock); } mutex_unlock(&dev->struct_mutex); diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 365e04ca9120..624d9bfc5c0b 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -2711,16 +2711,15 @@ static bool intel_crtc_has_pending_flip(struct drm_crtc *crtc) struct drm_device *dev = crtc->dev; struct drm_i915_private *dev_priv = dev->dev_private; struct intel_crtc *intel_crtc = to_intel_crtc(crtc); - unsigned long flags; bool pending; if (i915_reset_in_progress(&dev_priv->gpu_error) || intel_crtc->reset_counter != atomic_read(&dev_priv->gpu_error.reset_counter)) return false; - spin_lock_irqsave(&dev->event_lock, flags); + spin_lock_irq(&dev->event_lock); pending = to_intel_crtc(crtc)->unpin_work != NULL; - spin_unlock_irqrestore(&dev->event_lock, flags); + spin_unlock_irq(&dev->event_lock); return pending; } @@ -3431,14 +3430,13 @@ void intel_crtc_wait_for_pending_flips(struct drm_crtc *crtc) !intel_crtc_has_pending_flip(crtc), 60*HZ) == 0)) { struct intel_crtc *intel_crtc = to_intel_crtc(crtc); - unsigned long flags; - spin_lock_irqsave(&dev->event_lock, flags); + spin_lock_irq(&dev->event_lock); if (intel_crtc->unpin_work) { WARN_ONCE(1, "Removing stuck page flip\n"); page_flip_completed(intel_crtc); } - spin_unlock_irqrestore(&dev->event_lock, flags); + spin_unlock_irq(&dev->event_lock); } if (crtc->primary->fb) { @@ -9280,12 +9278,11 @@ static void intel_crtc_destroy(struct drm_crtc *crtc) struct intel_crtc *intel_crtc = to_intel_crtc(crtc); struct drm_device *dev = crtc->dev; struct intel_unpin_work *work; - unsigned long flags; - spin_lock_irqsave(&dev->event_lock, flags); + spin_lock_irq(&dev->event_lock); work = intel_crtc->unpin_work; intel_crtc->unpin_work = NULL; - spin_unlock_irqrestore(&dev->event_lock, flags); + spin_unlock_irq(&dev->event_lock); if (work) { cancel_work_sync(&work->work); @@ -9896,7 +9893,6 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc, enum pipe pipe = intel_crtc->pipe; struct intel_unpin_work *work; struct intel_engine_cs *ring; - unsigned long flags; int ret; //trigger software GT busyness calculation @@ -9940,7 +9936,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc, goto free_work; /* We borrow the event spin lock for protecting unpin_work */ - spin_lock_irqsave(&dev->event_lock, flags); + spin_lock_irq(&dev->event_lock); if (intel_crtc->unpin_work) { /* Before declaring the flip queue wedged, check if * the hardware completed the operation behind our backs. @@ -9950,7 +9946,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc, page_flip_completed(intel_crtc); } else { DRM_DEBUG_DRIVER("flip queue: crtc already busy\n"); - spin_unlock_irqrestore(&dev->event_lock, flags); + spin_unlock_irq(&dev->event_lock); drm_crtc_vblank_put(crtc); kfree(work); @@ -9958,7 +9954,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc, } } intel_crtc->unpin_work = work; - spin_unlock_irqrestore(&dev->event_lock, flags); + spin_unlock_irq(&dev->event_lock); if (atomic_read(&intel_crtc->unpin_work_count) >= 2) flush_workqueue(dev_priv->wq); @@ -10045,9 +10041,9 @@ cleanup_pending: mutex_unlock(&dev->struct_mutex); cleanup: - spin_lock_irqsave(&dev->event_lock, flags); + spin_lock_irq(&dev->event_lock); intel_crtc->unpin_work = NULL; - spin_unlock_irqrestore(&dev->event_lock, flags); + spin_unlock_irq(&dev->event_lock); drm_crtc_vblank_put(crtc); free_work: @@ -10058,9 +10054,9 @@ out_hang: intel_crtc_wait_for_pending_flips(crtc); ret = intel_pipe_set_base(crtc, crtc->x, crtc->y, fb); if (ret == 0 && event) { - spin_lock_irqsave(&dev->event_lock, flags); + spin_lock_irq(&dev->event_lock); drm_send_vblank_event(dev, pipe, event); - spin_unlock_irqrestore(&dev->event_lock, flags); + spin_unlock_irq(&dev->event_lock); } } return ret; @@ -13769,9 +13765,8 @@ void intel_modeset_preclose(struct drm_device *dev, struct drm_file *file) for_each_intel_crtc(dev, crtc) { struct intel_unpin_work *work; - unsigned long irqflags; - spin_lock_irqsave(&dev->event_lock, irqflags); + spin_lock_irq(&dev->event_lock); work = crtc->unpin_work; @@ -13781,6 +13776,6 @@ void intel_modeset_preclose(struct drm_device *dev, struct drm_file *file) work->event = NULL; } - spin_unlock_irqrestore(&dev->event_lock, irqflags); + spin_unlock_irq(&dev->event_lock); } }