public inbox for intel-gfx@lists.freedesktop.org
 help / color / mirror / Atom feed
From: Ben Widawsky <ben@bwidawsk.net>
To: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Intel Graphics Development <intel-gfx@lists.freedesktop.org>
Subject: Re: [PATCH 17/24] drm/i915: kill dev_priv->rps.lock
Date: Thu, 27 Jun 2013 20:35:17 -0700	[thread overview]
Message-ID: <20130628033517.GA1067@bwidawsk.net> (raw)
In-Reply-To: <1371037046-3732-18-git-send-email-daniel.vetter@ffwll.ch>

On Wed, Jun 12, 2013 at 01:37:19PM +0200, Daniel Vetter wrote:
> Now that the rps interrupt locking isn't clearly separated (at elast
> conceptually) from all the other interrupt locking having a different
> lock stopped making sense. With this we can (again) unifiy the
> ringbuffer irq refcounts without causing a massive confusion, but
> that's for the next patch.

I think the original reason for the RPS lock still makes sense, so I'd
say your assertion should be that it's not worth the extra complexity,
which I can agree with. (The original use of the rps_lock was just for
the rps workqueue, it expanded a bunch since then).

> 
> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> ---
>  drivers/gpu/drm/i915/i915_dma.c         |  1 -
>  drivers/gpu/drm/i915/i915_drv.h         |  8 ++++----
>  drivers/gpu/drm/i915/i915_irq.c         | 12 ++++++------
>  drivers/gpu/drm/i915/intel_pm.c         | 16 ++++++++--------
>  drivers/gpu/drm/i915/intel_ringbuffer.c |  8 ++++----
>  drivers/gpu/drm/i915/intel_ringbuffer.h |  2 +-
>  6 files changed, 23 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
> index b913b3d..14c3e9c 100644
> --- a/drivers/gpu/drm/i915/i915_dma.c
> +++ b/drivers/gpu/drm/i915/i915_dma.c
> @@ -1612,7 +1612,6 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
>  
>  	spin_lock_init(&dev_priv->irq_lock);
>  	spin_lock_init(&dev_priv->gpu_error.lock);
> -	spin_lock_init(&dev_priv->rps.lock);
>  	spin_lock_init(&dev_priv->backlight.lock);
>  	mutex_init(&dev_priv->dpio_lock);
>  
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 07954b2..42d1363 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -691,12 +691,12 @@ struct i915_suspend_saved_registers {
>  };
>  
>  struct intel_gen6_power_mgmt {
> +	/* work and pm_iir are protected by dev_priv->irq_lock */
>  	struct work_struct work;
> -	struct delayed_work vlv_work;
>  	u32 pm_iir;
> -	/* lock - irqsave spinlock that protectects the work_struct and
> -	 * pm_iir. */
> -	spinlock_t lock;
> +
> +	/* On vlv we need to manually drop to Vmin with a delayed work. */
> +	struct delayed_work vlv_work;
A bit unrelated, but meh.
>  
>  	/* The below variables an all the rps hw state are protected by
>  	 * dev->struct mutext. */
> diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
> index 752b98d..cd7135d 100644
> --- a/drivers/gpu/drm/i915/i915_irq.c
> +++ b/drivers/gpu/drm/i915/i915_irq.c
> @@ -696,13 +696,13 @@ static void gen6_pm_rps_work(struct work_struct *work)
>  	u32 pm_iir, pm_imr;
>  	u8 new_delay;
>  
> -	spin_lock_irq(&dev_priv->rps.lock);
> +	spin_lock_irq(&dev_priv->irq_lock);
>  	pm_iir = dev_priv->rps.pm_iir;
>  	dev_priv->rps.pm_iir = 0;
>  	pm_imr = I915_READ(GEN6_PMIMR);
>  	/* Make sure not to corrupt PMIMR state used by ringbuffer code */
>  	I915_WRITE(GEN6_PMIMR, pm_imr & ~GEN6_PM_RPS_EVENTS);
> -	spin_unlock_irq(&dev_priv->rps.lock);
> +	spin_unlock_irq(&dev_priv->irq_lock);
>  
>  	if ((pm_iir & GEN6_PM_RPS_EVENTS) == 0)
>  		return;
> @@ -856,11 +856,11 @@ static void gen6_rps_irq_handler(struct drm_i915_private *dev_priv,
>  	 * The mask bit in IMR is cleared by dev_priv->rps.work.
>  	 */
>  
> -	spin_lock(&dev_priv->rps.lock);
> +	spin_lock(&dev_priv->irq_lock);
>  	dev_priv->rps.pm_iir |= pm_iir;
>  	I915_WRITE(GEN6_PMIMR, dev_priv->rps.pm_iir);
>  	POSTING_READ(GEN6_PMIMR);
> -	spin_unlock(&dev_priv->rps.lock);
> +	spin_unlock(&dev_priv->irq_lock);
>  
>  	queue_work(dev_priv->wq, &dev_priv->rps.work);
>  }
> @@ -933,12 +933,12 @@ static void hsw_pm_irq_handler(struct drm_i915_private *dev_priv,
>  			       u32 pm_iir)
>  {
>  	if (pm_iir & GEN6_PM_RPS_EVENTS) {
> -		spin_lock(&dev_priv->rps.lock);
> +		spin_lock(&dev_priv->irq_lock);
>  		dev_priv->rps.pm_iir |= pm_iir & GEN6_PM_RPS_EVENTS;
>  		I915_WRITE(GEN6_PMIMR, dev_priv->rps.pm_iir);
>  		/* never want to mask useful interrupts. (also posting read) */
>  		WARN_ON(I915_READ_NOTRACE(GEN6_PMIMR) & ~GEN6_PM_RPS_EVENTS);
> -		spin_unlock(&dev_priv->rps.lock);
> +		spin_unlock(&dev_priv->irq_lock);
>  
>  		queue_work(dev_priv->wq, &dev_priv->rps.work);
>  	}
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index adc44e4..6a5cfb5 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -3128,9 +3128,9 @@ static void gen6_disable_rps(struct drm_device *dev)
>  	 * register (PMIMR) to mask PM interrupts. The only risk is in leaving
>  	 * stale bits in PMIIR and PMIMR which gen6_enable_rps will clean up. */
>  
> -	spin_lock_irq(&dev_priv->rps.lock);
> +	spin_lock_irq(&dev_priv->irq_lock);
>  	dev_priv->rps.pm_iir = 0;
> -	spin_unlock_irq(&dev_priv->rps.lock);
> +	spin_unlock_irq(&dev_priv->irq_lock);
>  
>  	I915_WRITE(GEN6_PMIIR, GEN6_PM_RPS_EVENTS);
>  }
> @@ -3147,9 +3147,9 @@ static void valleyview_disable_rps(struct drm_device *dev)
>  	 * register (PMIMR) to mask PM interrupts. The only risk is in leaving
>  	 * stale bits in PMIIR and PMIMR which gen6_enable_rps will clean up. */
>  
> -	spin_lock_irq(&dev_priv->rps.lock);
> +	spin_lock_irq(&dev_priv->irq_lock);
>  	dev_priv->rps.pm_iir = 0;
> -	spin_unlock_irq(&dev_priv->rps.lock);
> +	spin_unlock_irq(&dev_priv->irq_lock);
>  
>  	I915_WRITE(GEN6_PMIIR, I915_READ(GEN6_PMIIR));
>  
> @@ -3314,13 +3314,13 @@ static void gen6_enable_rps(struct drm_device *dev)
>  
>  	/* requires MSI enabled */
>  	I915_WRITE(GEN6_PMIER, I915_READ(GEN6_PMIER) | GEN6_PM_RPS_EVENTS);
> -	spin_lock_irq(&dev_priv->rps.lock);
> +	spin_lock_irq(&dev_priv->irq_lock);
>  	/* FIXME: Our interrupt enabling sequence is bonghits.
>  	 * dev_priv->rps.pm_iir really should be 0 here. */
>  	dev_priv->rps.pm_iir = 0;
>  	I915_WRITE(GEN6_PMIMR, I915_READ(GEN6_PMIMR) & ~GEN6_PM_RPS_EVENTS);
>  	I915_WRITE(GEN6_PMIIR, GEN6_PM_RPS_EVENTS);
> -	spin_unlock_irq(&dev_priv->rps.lock);
> +	spin_unlock_irq(&dev_priv->irq_lock);
>  	/* unmask all PM interrupts */
>  	I915_WRITE(GEN6_PMINTRMSK, 0);
>  
> @@ -3585,10 +3585,10 @@ static void valleyview_enable_rps(struct drm_device *dev)
>  
>  	/* requires MSI enabled */
>  	I915_WRITE(GEN6_PMIER, GEN6_PM_RPS_EVENTS);
> -	spin_lock_irq(&dev_priv->rps.lock);
> +	spin_lock_irq(&dev_priv->irq_lock);
>  	WARN_ON(dev_priv->rps.pm_iir != 0);
>  	I915_WRITE(GEN6_PMIMR, 0);
> -	spin_unlock_irq(&dev_priv->rps.lock);
> +	spin_unlock_irq(&dev_priv->irq_lock);
>  	/* enable all PM interrupts */
>  	I915_WRITE(GEN6_PMINTRMSK, 0);
>  
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index 1ef081c..a7c9934 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -1053,14 +1053,14 @@ hsw_vebox_get_irq(struct intel_ring_buffer *ring)
>  	if (!dev->irq_enabled)
>  		return false;
>  
> -	spin_lock_irqsave(&dev_priv->rps.lock, flags);
> +	spin_lock_irqsave(&dev_priv->irq_lock, flags);
>  	if (ring->irq_refcount.pm++ == 0) {
>  		u32 pm_imr = I915_READ(GEN6_PMIMR);
>  		I915_WRITE_IMR(ring, ~ring->irq_enable_mask);
>  		I915_WRITE(GEN6_PMIMR, pm_imr & ~ring->irq_enable_mask);
>  		POSTING_READ(GEN6_PMIMR);
>  	}
> -	spin_unlock_irqrestore(&dev_priv->rps.lock, flags);
> +	spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
>  
>  	return true;
>  }
> @@ -1075,14 +1075,14 @@ hsw_vebox_put_irq(struct intel_ring_buffer *ring)
>  	if (!dev->irq_enabled)
>  		return;
>  
> -	spin_lock_irqsave(&dev_priv->rps.lock, flags);
> +	spin_lock_irqsave(&dev_priv->irq_lock, flags);
>  	if (--ring->irq_refcount.pm == 0) {
>  		u32 pm_imr = I915_READ(GEN6_PMIMR);
>  		I915_WRITE_IMR(ring, ~0);
>  		I915_WRITE(GEN6_PMIMR, pm_imr | ring->irq_enable_mask);
>  		POSTING_READ(GEN6_PMIMR);
>  	}
> -	spin_unlock_irqrestore(&dev_priv->rps.lock, flags);
> +	spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
>  }
>  
>  static int
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
> index efc403d..f960805 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.h
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
> @@ -76,7 +76,7 @@ struct  intel_ring_buffer {
>  
>  	struct {
>  		u32	gt; /*  protected by dev_priv->irq_lock */
> -		u32	pm; /*  protected by dev_priv->rps.lock (sucks) */
> +		u32	pm; /*  protected by dev_priv->irq_lock */
>  	} irq_refcount;
>  	u32		irq_enable_mask;	/* bitmask to enable ring interrupt */
>  	u32		trace_irq_seqno;
> -- 
> 1.8.1.4
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Ben Widawsky, Intel Open Source Technology Center

  reply	other threads:[~2013-06-28  3:32 UTC|newest]

Thread overview: 86+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-06-12 11:37 [PATCH 00/24] irq locking review Daniel Vetter
2013-06-12 11:37 ` [PATCH 01/24] drm/i915: fix locking around ironlake_enable|disable_display_irq Daniel Vetter
2013-06-25 12:26   ` [PATCH] " Daniel Vetter
2013-06-26 21:15     ` Paulo Zanoni
2013-06-27 10:37       ` Daniel Vetter
2013-06-12 11:37 ` [PATCH 02/24] drm/i915: close tiny race in the ilk pcu even interrupt setup Daniel Vetter
2013-06-26 21:20   ` Paulo Zanoni
2013-06-12 11:37 ` [PATCH 03/24] drm/i915: assert_spin_locked for pipestat interrupt enable/disable Daniel Vetter
2013-06-26 21:44   ` Paulo Zanoni
2013-06-12 11:37 ` [PATCH 04/24] drm/i915: s/hotplug_irq_storm_detect/intel_hpd_irq_handler/ Daniel Vetter
2013-06-12 14:22   ` Egbert Eich
2013-06-12 11:37 ` [PATCH 05/24] drm/i915: fold the hpd_irq_setup call into intel_hpd_irq_handler Daniel Vetter
     [not found]   ` <20920.34096.704203.67316@linux-qknr.site>
2013-06-12 15:00     ` Daniel Vetter
2013-06-12 11:37 ` [PATCH 06/24] drm/i915: fold the queue_work " Daniel Vetter
2013-06-12 14:29   ` Egbert Eich
2013-06-12 11:37 ` [PATCH 07/24] drm/i915: fold the no-irq check " Daniel Vetter
2013-06-12 14:33   ` Egbert Eich
2013-06-26 22:35     ` Paulo Zanoni
2013-06-27 10:39       ` Daniel Vetter
2013-06-27 11:44       ` [PATCH 1/8] drm/i915: fix locking around ironlake_enable|disable_display_irq Daniel Vetter
2013-06-27 11:44         ` [PATCH 2/8] drm/i915: close tiny race in the ilk pcu even interrupt setup Daniel Vetter
2013-06-27 11:45         ` [PATCH 3/8] drm/i915: assert_spin_locked for pipestat interrupt enable/disable Daniel Vetter
2013-06-27 11:45         ` [PATCH 4/8] drm/i915: s/hotplug_irq_storm_detect/intel_hpd_irq_handler/ Daniel Vetter
2013-06-27 11:45         ` [PATCH 5/8] drm/i915: fold the hpd_irq_setup call into intel_hpd_irq_handler Daniel Vetter
2013-06-27 11:45         ` [PATCH 6/8] drm/i915: fold the queue_work " Daniel Vetter
2013-06-27 12:13           ` Chris Wilson
2013-06-27 11:45         ` [PATCH 7/8] drm/i915: fold the no-irq check " Daniel Vetter
2013-06-27 12:14           ` Chris Wilson
2013-06-27 11:45         ` [PATCH 8/8] drm/i915: fix hpd interrupt register locking Daniel Vetter
2013-06-27 14:41           ` Paulo Zanoni
2013-06-27 15:52             ` [PATCH 1/6] drm/i915: assert_spin_locked for pipestat interrupt enable/disable Daniel Vetter
2013-06-27 15:52               ` [PATCH 2/6] drm/i915: s/hotplug_irq_storm_detect/intel_hpd_irq_handler/ Daniel Vetter
2013-06-27 15:52               ` [PATCH 3/6] drm/i915: fold the hpd_irq_setup call into intel_hpd_irq_handler Daniel Vetter
2013-06-27 15:52               ` [PATCH 4/6] drm/i915: fold the queue_work " Daniel Vetter
2013-06-27 15:52               ` [PATCH 5/6] drm/i915: fold the no-irq check " Daniel Vetter
2013-06-27 15:52               ` [PATCH 6/6] drm/i915: fix hpd interrupt register locking Daniel Vetter
2013-07-04 19:22               ` [PATCH 1/6] drm/i915: assert_spin_locked for pipestat interrupt enable/disable Daniel Vetter
2013-06-27 17:44             ` [PATCH 8/8] drm/i915: fix hpd interrupt register locking Daniel Vetter
2013-06-12 11:37 ` [PATCH 08/24] " Daniel Vetter
2013-06-12 14:59   ` Egbert Eich
2013-06-12 15:10     ` Daniel Vetter
2013-06-12 11:37 ` [PATCH 09/24] drm/i915: extract ibx_display_interrupt_update Daniel Vetter
2013-06-25 12:27   ` [PATCH] " Daniel Vetter
2013-06-12 11:37 ` [PATCH 10/24] drm/i915: remove SERR_INT clearing in the postinstall hook Daniel Vetter
2013-06-27 19:34   ` Paulo Zanoni
2013-07-04 19:49     ` Daniel Vetter
2013-06-12 11:37 ` [PATCH 11/24] drm/i915: improve SERR_INT clearing for fifo underrun reporting Daniel Vetter
2013-06-27 20:19   ` Paulo Zanoni
2013-07-04 19:55     ` Daniel Vetter
2013-06-12 11:37 ` [PATCH 12/24] drm/i915: improve GEN7_ERR_INT " Daniel Vetter
2013-06-12 11:37 ` [PATCH 13/24] drm/i915: kill lpt pch transcoder->crtc mapping code for fifo underruns Daniel Vetter
2013-06-12 13:04   ` Paulo Zanoni
2013-06-12 14:46     ` [PATCH] " Daniel Vetter
2013-06-27 20:45       ` Paulo Zanoni
2013-07-04 20:41         ` Daniel Vetter
2013-06-12 11:37 ` [PATCH 14/24] drm/i915: irq handlers don't need interrupt-safe spinlocks Daniel Vetter
2013-06-25 12:27   ` [PATCH] " Daniel Vetter
2013-06-27 21:14     ` Paulo Zanoni
2013-06-27 22:40       ` Daniel Vetter
2013-06-28 16:57         ` Paulo Zanoni
2013-06-12 11:37 ` [PATCH 15/24] drm/i915: streamline hsw_pm_irq_handler Daniel Vetter
2013-06-25 12:28   ` [PATCH] " Daniel Vetter
2013-06-12 11:37 ` [PATCH 16/24] drm/i915: queue work outside spinlock in hsw_pm_irq_handler Daniel Vetter
2013-06-12 11:37 ` [PATCH 17/24] drm/i915: kill dev_priv->rps.lock Daniel Vetter
2013-06-28  3:35   ` Ben Widawsky [this message]
2013-06-28  3:35   ` Ben Widawsky
2013-06-12 11:37 ` [PATCH 18/24] drm/i915: unify ring irq refcounts (again) Daniel Vetter
2013-06-28 17:24   ` Ben Widawsky
2013-07-04 20:52     ` Daniel Vetter
2013-06-12 11:37 ` [PATCH 19/24] drm/i915: don't enable PM_VEBOX_CS_ERROR_INTERRUPT Daniel Vetter
2013-06-12 17:13   ` Ben Widawsky
2013-06-12 17:18     ` Daniel Vetter
2013-06-12 18:19       ` Ben Widawsky
2013-06-12 18:32         ` Daniel Vetter
2013-06-12 18:51           ` Ben Widawsky
2013-06-28 17:25           ` Ben Widawsky
2013-06-12 11:37 ` [PATCH 20/24] drm/i915: kill bogus GTIIR clearing in vlv_preinstall hook Daniel Vetter
2013-06-28 17:01   ` Ben Widawsky
2013-07-04 20:56     ` Daniel Vetter
2013-06-12 11:37 ` [PATCH 21/24] drm/i915: unify PM interrupt preinstall sequence Daniel Vetter
2013-06-28 17:26   ` Ben Widawsky
2013-07-04 21:03     ` Daniel Vetter
2013-06-12 11:37 ` [PATCH 22/24] drm/i915: unify GT/PM irq postinstall code Daniel Vetter
2013-06-12 11:37 ` [PATCH 23/24] drm/i915: extract rps interrupt enable/disable helpers Daniel Vetter
2013-06-12 11:37 ` [PATCH 24/24] drm/i915: simplify rps interrupt enabling/disabling sequence Daniel Vetter
2013-06-12 22:32   ` Ben Widawsky

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20130628033517.GA1067@bwidawsk.net \
    --to=ben@bwidawsk.net \
    --cc=daniel.vetter@ffwll.ch \
    --cc=intel-gfx@lists.freedesktop.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox