[Intel-gfx] [PATCH 18/20] drm/i915: Move the get/put irq locking into the caller
Tvrtko Ursulin
tvrtko.ursulin at linux.intel.com
Fri Jul 1 14:39:16 UTC 2016
On 01/07/16 12:22, Chris Wilson wrote:
> With only a single callsite for intel_engine_cs->irq_get and ->irq_put,
> we can reduce the code size by moving the common preamble into the
> caller, and we can also eliminate the reference counting.
>
> For completeness, as we are no longer doing reference counting on irq,
> rename the get/put vfunctions to enable/disable respectively and are
> able to review the use of posting reads. We only require the
> serialisation with hardware when enabling the interrupt (i.e. so we
> cannot miss an interrupt by going to sleep before the hardware truly
> enables it).
>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> ---
> drivers/gpu/drm/i915/i915_irq.c | 8 +-
> drivers/gpu/drm/i915/intel_breadcrumbs.c | 10 +-
> drivers/gpu/drm/i915/intel_lrc.c | 34 ++---
> drivers/gpu/drm/i915/intel_ringbuffer.c | 237 +++++++++----------------------
> drivers/gpu/drm/i915/intel_ringbuffer.h | 5 +-
> 5 files changed, 92 insertions(+), 202 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
> index 7724bae27bcf..be25b7bdacfe 100644
> --- a/drivers/gpu/drm/i915/i915_irq.c
> +++ b/drivers/gpu/drm/i915/i915_irq.c
> @@ -259,12 +259,12 @@ static void ilk_update_gt_irq(struct drm_i915_private *dev_priv,
> dev_priv->gt_irq_mask &= ~interrupt_mask;
> dev_priv->gt_irq_mask |= (~enabled_irq_mask & interrupt_mask);
> I915_WRITE(GTIMR, dev_priv->gt_irq_mask);
> - POSTING_READ(GTIMR);
> }
>
> void gen5_enable_gt_irq(struct drm_i915_private *dev_priv, uint32_t mask)
> {
> ilk_update_gt_irq(dev_priv, mask, mask);
> + POSTING_READ_FW(GTIMR);
> }
>
> void gen5_disable_gt_irq(struct drm_i915_private *dev_priv, uint32_t mask)
> @@ -2819,9 +2819,9 @@ ring_idle(struct intel_engine_cs *engine, u32 seqno)
> }
>
> static bool
> -ipehr_is_semaphore_wait(struct drm_i915_private *dev_priv, u32 ipehr)
> +ipehr_is_semaphore_wait(struct intel_engine_cs *engine, u32 ipehr)
> {
> - if (INTEL_GEN(dev_priv) >= 8) {
> + if (INTEL_GEN(engine->i915) >= 8) {
> return (ipehr >> 23) == 0x1c;
> } else {
> ipehr &= ~MI_SEMAPHORE_SYNC_MASK;
> @@ -2892,7 +2892,7 @@ semaphore_waits_for(struct intel_engine_cs *engine, u32 *seqno)
> return NULL;
>
> ipehr = I915_READ(RING_IPEHR(engine->mmio_base));
> - if (!ipehr_is_semaphore_wait(engine->i915, ipehr))
> + if (!ipehr_is_semaphore_wait(engine, ipehr))
> return NULL;
>
> /*
> diff --git a/drivers/gpu/drm/i915/intel_breadcrumbs.c b/drivers/gpu/drm/i915/intel_breadcrumbs.c
> index 3b8313b87ce4..28bc72b601b8 100644
> --- a/drivers/gpu/drm/i915/intel_breadcrumbs.c
> +++ b/drivers/gpu/drm/i915/intel_breadcrumbs.c
> @@ -50,12 +50,18 @@ static void irq_enable(struct intel_engine_cs *engine)
> * just in case.
> */
> engine->irq_posted = true;
> - WARN_ON(!engine->irq_get(engine));
> +
> + spin_lock_irq(&engine->i915->irq_lock);
> + engine->irq_enable(engine);
> + spin_unlock_irq(&engine->i915->irq_lock);
> }
>
> static void irq_disable(struct intel_engine_cs *engine)
> {
> - engine->irq_put(engine);
> + spin_lock_irq(&engine->i915->irq_lock);
> + engine->irq_disable(engine);
> + spin_unlock_irq(&engine->i915->irq_lock);
> +
> engine->irq_posted = false;
> }
>
> diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
> index f1a01137334c..380175149916 100644
> --- a/drivers/gpu/drm/i915/intel_lrc.c
> +++ b/drivers/gpu/drm/i915/intel_lrc.c
> @@ -1617,36 +1617,18 @@ static int gen8_emit_bb_start(struct drm_i915_gem_request *req,
> return 0;
> }
>
> -static bool gen8_logical_ring_get_irq(struct intel_engine_cs *engine)
> +static void gen8_logical_ring_enable_irq(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
> -
> - if (WARN_ON(!intel_irqs_enabled(dev_priv)))
> - return false;
> -
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (engine->irq_refcount++ == 0) {
> - I915_WRITE_IMR(engine,
> - ~(engine->irq_enable_mask | engine->irq_keep_mask));
> - POSTING_READ(RING_IMR(engine->mmio_base));
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> -
> - return true;
> + I915_WRITE_IMR(engine,
> + ~(engine->irq_enable_mask | engine->irq_keep_mask));
> + POSTING_READ_FW(RING_IMR(engine->mmio_base));
> }
>
> -static void gen8_logical_ring_put_irq(struct intel_engine_cs *engine)
> +static void gen8_logical_ring_disable_irq(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
> -
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (--engine->irq_refcount == 0) {
> - I915_WRITE_IMR(engine, ~engine->irq_keep_mask);
> - POSTING_READ(RING_IMR(engine->mmio_base));
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> + I915_WRITE_IMR(engine, ~engine->irq_keep_mask);
> }
>
> static int gen8_emit_flush(struct drm_i915_gem_request *request,
> @@ -1966,8 +1948,8 @@ logical_ring_default_vfuncs(struct intel_engine_cs *engine)
> engine->init_hw = gen8_init_common_ring;
> engine->emit_request = gen8_emit_request;
> engine->emit_flush = gen8_emit_flush;
> - engine->irq_get = gen8_logical_ring_get_irq;
> - engine->irq_put = gen8_logical_ring_put_irq;
> + engine->irq_enable = gen8_logical_ring_enable_irq;
> + engine->irq_disable = gen8_logical_ring_disable_irq;
> engine->emit_bb_start = gen8_emit_bb_start;
> if (IS_BXT_REVID(engine->i915, 0, BXT_REVID_A1))
> engine->irq_seqno_barrier = bxt_a_seqno_barrier;
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index d919e72f1328..eb62f3012aa6 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -1636,103 +1636,54 @@ gen6_seqno_barrier(struct intel_engine_cs *engine)
> spin_unlock_irq(&dev_priv->uncore.lock);
> }
>
> -static bool
> -gen5_ring_get_irq(struct intel_engine_cs *engine)
> +static void
> +gen5_irq_enable(struct intel_engine_cs *engine)
> {
> - struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
> -
> - if (WARN_ON(!intel_irqs_enabled(dev_priv)))
> - return false;
> -
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (engine->irq_refcount++ == 0)
> - gen5_enable_gt_irq(dev_priv, engine->irq_enable_mask);
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> -
> - return true;
> + gen5_enable_gt_irq(engine->i915, engine->irq_enable_mask);
> }
>
> static void
> -gen5_ring_put_irq(struct intel_engine_cs *engine)
> +gen5_irq_disable(struct intel_engine_cs *engine)
> {
> - struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
> -
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (--engine->irq_refcount == 0)
> - gen5_disable_gt_irq(dev_priv, engine->irq_enable_mask);
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> + gen5_disable_gt_irq(engine->i915, engine->irq_enable_mask);
> }
>
> -static bool
> -i9xx_ring_get_irq(struct intel_engine_cs *engine)
> +static void
> +i9xx_irq_enable(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
> -
> - if (!intel_irqs_enabled(dev_priv))
> - return false;
> -
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (engine->irq_refcount++ == 0) {
> - dev_priv->irq_mask &= ~engine->irq_enable_mask;
> - I915_WRITE(IMR, dev_priv->irq_mask);
> - POSTING_READ(IMR);
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
>
> - return true;
> + dev_priv->irq_mask &= ~engine->irq_enable_mask;
> + I915_WRITE(IMR, dev_priv->irq_mask);
> + POSTING_READ_FW(RING_IMR(engine->mmio_base));
> }
>
> static void
> -i9xx_ring_put_irq(struct intel_engine_cs *engine)
> +i9xx_irq_disable(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
>
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (--engine->irq_refcount == 0) {
> - dev_priv->irq_mask |= engine->irq_enable_mask;
> - I915_WRITE(IMR, dev_priv->irq_mask);
> - POSTING_READ(IMR);
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> + dev_priv->irq_mask |= engine->irq_enable_mask;
> + I915_WRITE(IMR, dev_priv->irq_mask);
> }
>
> -static bool
> -i8xx_ring_get_irq(struct intel_engine_cs *engine)
> +static void
> +i8xx_irq_enable(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
>
> - if (!intel_irqs_enabled(dev_priv))
> - return false;
> -
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (engine->irq_refcount++ == 0) {
> - dev_priv->irq_mask &= ~engine->irq_enable_mask;
> - I915_WRITE16(IMR, dev_priv->irq_mask);
> - POSTING_READ16(IMR);
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> -
> - return true;
> + dev_priv->irq_mask &= ~engine->irq_enable_mask;
> + I915_WRITE16(IMR, dev_priv->irq_mask);
> + POSTING_READ16(RING_IMR(engine->mmio_base));
> }
>
> static void
> -i8xx_ring_put_irq(struct intel_engine_cs *engine)
> +i8xx_irq_disable(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
>
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (--engine->irq_refcount == 0) {
> - dev_priv->irq_mask |= engine->irq_enable_mask;
> - I915_WRITE16(IMR, dev_priv->irq_mask);
> - POSTING_READ16(IMR);
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> + dev_priv->irq_mask |= engine->irq_enable_mask;
> + I915_WRITE16(IMR, dev_priv->irq_mask);
> }
>
> static int
> @@ -1773,122 +1724,74 @@ i9xx_add_request(struct drm_i915_gem_request *req)
> return 0;
> }
>
> -static bool
> -gen6_ring_get_irq(struct intel_engine_cs *engine)
> +static void
> +gen6_irq_enable(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
> -
> - if (WARN_ON(!intel_irqs_enabled(dev_priv)))
> - return false;
>
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (engine->irq_refcount++ == 0) {
> - if (HAS_L3_DPF(dev_priv) && engine->id == RCS)
> - I915_WRITE_IMR(engine,
> - ~(engine->irq_enable_mask |
> - GT_PARITY_ERROR(dev_priv)));
> - else
> - I915_WRITE_IMR(engine, ~engine->irq_enable_mask);
> - gen5_enable_gt_irq(dev_priv, engine->irq_enable_mask);
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> -
> - return true;
> + if (HAS_L3_DPF(dev_priv) && engine->id == RCS)
> + I915_WRITE_IMR(engine,
> + ~(engine->irq_enable_mask |
> + GT_PARITY_ERROR(dev_priv)));
> + else
> + I915_WRITE_IMR(engine, ~engine->irq_enable_mask);
> + gen5_enable_gt_irq(dev_priv, engine->irq_enable_mask);
> }
>
> static void
> -gen6_ring_put_irq(struct intel_engine_cs *engine)
> +gen6_irq_disable(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
>
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (--engine->irq_refcount == 0) {
> - if (HAS_L3_DPF(dev_priv) && engine->id == RCS)
> - I915_WRITE_IMR(engine, ~GT_PARITY_ERROR(dev_priv));
> - else
> - I915_WRITE_IMR(engine, ~0);
> - gen5_disable_gt_irq(dev_priv, engine->irq_enable_mask);
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> + if (HAS_L3_DPF(dev_priv) && engine->id == RCS)
> + I915_WRITE_IMR(engine, ~GT_PARITY_ERROR(dev_priv));
> + else
> + I915_WRITE_IMR(engine, ~0);
> + gen5_disable_gt_irq(dev_priv, engine->irq_enable_mask);
> }
>
> -static bool
> -hsw_vebox_get_irq(struct intel_engine_cs *engine)
> +static void
> +hsw_vebox_irq_enable(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
> -
> - if (WARN_ON(!intel_irqs_enabled(dev_priv)))
> - return false;
>
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (engine->irq_refcount++ == 0) {
> - I915_WRITE_IMR(engine, ~engine->irq_enable_mask);
> - gen6_enable_pm_irq(dev_priv, engine->irq_enable_mask);
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> -
> - return true;
> + I915_WRITE_IMR(engine, ~engine->irq_enable_mask);
> + gen6_enable_pm_irq(dev_priv, engine->irq_enable_mask);
> }
>
> static void
> -hsw_vebox_put_irq(struct intel_engine_cs *engine)
> +hsw_vebox_irq_disable(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
>
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (--engine->irq_refcount == 0) {
> - I915_WRITE_IMR(engine, ~0);
> - gen6_disable_pm_irq(dev_priv, engine->irq_enable_mask);
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> + I915_WRITE_IMR(engine, ~0);
> + gen6_disable_pm_irq(dev_priv, engine->irq_enable_mask);
> }
>
> -static bool
> -gen8_ring_get_irq(struct intel_engine_cs *engine)
> +static void
> +gen8_irq_enable(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
>
> - if (WARN_ON(!intel_irqs_enabled(dev_priv)))
> - return false;
> -
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (engine->irq_refcount++ == 0) {
> - if (HAS_L3_DPF(dev_priv) && engine->id == RCS) {
> - I915_WRITE_IMR(engine,
> - ~(engine->irq_enable_mask |
> - GT_RENDER_L3_PARITY_ERROR_INTERRUPT));
> - } else {
> - I915_WRITE_IMR(engine, ~engine->irq_enable_mask);
> - }
> - POSTING_READ(RING_IMR(engine->mmio_base));
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> -
> - return true;
> + if (HAS_L3_DPF(dev_priv) && engine->id == RCS)
> + I915_WRITE_IMR(engine,
> + ~(engine->irq_enable_mask |
> + GT_RENDER_L3_PARITY_ERROR_INTERRUPT));
> + else
> + I915_WRITE_IMR(engine, ~engine->irq_enable_mask);
> + POSTING_READ_FW(RING_IMR(engine->mmio_base));
> }
>
> static void
> -gen8_ring_put_irq(struct intel_engine_cs *engine)
> +gen8_irq_disable(struct intel_engine_cs *engine)
> {
> struct drm_i915_private *dev_priv = engine->i915;
> - unsigned long flags;
>
> - spin_lock_irqsave(&dev_priv->irq_lock, flags);
> - if (--engine->irq_refcount == 0) {
> - if (HAS_L3_DPF(dev_priv) && engine->id == RCS) {
> - I915_WRITE_IMR(engine,
> - ~GT_RENDER_L3_PARITY_ERROR_INTERRUPT);
> - } else {
> - I915_WRITE_IMR(engine, ~0);
> - }
> - POSTING_READ(RING_IMR(engine->mmio_base));
> - }
> - spin_unlock_irqrestore(&dev_priv->irq_lock, flags);
> + if (HAS_L3_DPF(dev_priv) && engine->id == RCS)
> + I915_WRITE_IMR(engine,
> + ~GT_RENDER_L3_PARITY_ERROR_INTERRUPT);
> + else
> + I915_WRITE_IMR(engine, ~0);
> }
>
> static int
> @@ -2909,23 +2812,23 @@ static void intel_ring_init_irq(struct drm_i915_private *dev_priv,
> struct intel_engine_cs *engine)
> {
> if (INTEL_GEN(dev_priv) >= 8) {
> - engine->irq_get = gen8_ring_get_irq;
> - engine->irq_put = gen8_ring_put_irq;
> + engine->irq_enable = gen8_irq_enable;
> + engine->irq_disable = gen8_irq_disable;
> engine->irq_seqno_barrier = gen6_seqno_barrier;
> } else if (INTEL_GEN(dev_priv) >= 6) {
> - engine->irq_get = gen6_ring_get_irq;
> - engine->irq_put = gen6_ring_put_irq;
> + engine->irq_enable = gen6_irq_enable;
> + engine->irq_disable = gen6_irq_disable;
> engine->irq_seqno_barrier = gen6_seqno_barrier;
> } else if (INTEL_GEN(dev_priv) >= 5) {
> - engine->irq_get = gen5_ring_get_irq;
> - engine->irq_put = gen5_ring_put_irq;
> + engine->irq_enable = gen5_irq_enable;
> + engine->irq_disable = gen5_irq_disable;
> engine->irq_seqno_barrier = gen5_seqno_barrier;
> } else if (INTEL_GEN(dev_priv) >= 3) {
> - engine->irq_get = i9xx_ring_get_irq;
> - engine->irq_put = i9xx_ring_put_irq;
> + engine->irq_enable = i9xx_irq_enable;
> + engine->irq_disable = i9xx_irq_disable;
> } else {
> - engine->irq_get = i8xx_ring_get_irq;
> - engine->irq_put = i8xx_ring_put_irq;
> + engine->irq_enable = i8xx_irq_enable;
> + engine->irq_disable = i8xx_irq_disable;
> }
> }
>
> @@ -3116,8 +3019,8 @@ int intel_init_vebox_ring_buffer(struct drm_device *dev)
> GT_RENDER_USER_INTERRUPT << GEN8_VECS_IRQ_SHIFT;
> } else {
> engine->irq_enable_mask = PM_VEBOX_USER_INTERRUPT;
> - engine->irq_get = hsw_vebox_get_irq;
> - engine->irq_put = hsw_vebox_put_irq;
> + engine->irq_enable = hsw_vebox_irq_enable;
> + engine->irq_disable = hsw_vebox_irq_disable;
> }
>
> return intel_init_ring_buffer(dev, engine);
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
> index 40c004134b76..8eb96408a3e2 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.h
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
> @@ -189,11 +189,10 @@ struct intel_engine_cs {
> struct intel_hw_status_page status_page;
> struct i915_ctx_workarounds wa_ctx;
>
> - unsigned irq_refcount; /* protected by dev_priv->irq_lock */
> bool irq_posted;
> u32 irq_enable_mask; /* bitmask to enable ring interrupt */
> - bool __must_check (*irq_get)(struct intel_engine_cs *ring);
> - void (*irq_put)(struct intel_engine_cs *ring);
> + void (*irq_enable)(struct intel_engine_cs *ring);
> + void (*irq_disable)(struct intel_engine_cs *ring);
>
> int (*init_hw)(struct intel_engine_cs *ring);
>
>
I think my only complaint here was that the caller has to know about
locking now. But it is a single call site so OK.
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
Regards,
Tvrtko
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