Attachment 56480 Details for Bug 45492 – Use request->head to guess current ring->head

[patch] Use request->head to guess current ring->head

0002-drm-i915-Record-the-tail-of-each-request-and-use-it-.patch (text/plain), 3.33 KB, created by Chris Wilson on 2012-02-01 14:42:02 UTC

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Creator: Chris Wilson

Created: 2012-02-01 14:42:02 UTC

Size: 3.33 KB

patch

obsolete

>From eaaaa2c41fbb8663d5158183449b202367373954 Mon Sep 17 00:00:00 2001
>From: Chris Wilson <chris@chris-wilson.co.uk>
>Date: Wed, 1 Feb 2012 21:29:31 +0000
>Subject: [PATCH 2/2] drm/i915: Record the tail of each request and use it to
> estimate the head
>
>Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
>---
> drivers/gpu/drm/i915/i915_drv.h         |    3 +++
> drivers/gpu/drm/i915/i915_gem.c         |   10 ++++++----
> drivers/gpu/drm/i915/intel_ringbuffer.c |   11 +++++++++++
> drivers/gpu/drm/i915/intel_ringbuffer.h |    2 ++
> 4 files changed, 22 insertions(+), 4 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
>index 4ee0793..b26e951 100644
>--- a/drivers/gpu/drm/i915/i915_drv.h
>+++ b/drivers/gpu/drm/i915/i915_drv.h
>@@ -945,6 +945,9 @@ struct drm_i915_gem_request {
> 	/** GEM sequence number associated with this request. */
> 	uint32_t seqno;
> 
>+	/** Postion in the ringbuffer of the start of the request */
>+	u32 acthd;
>+
> 	/** Time at which this request was emitted, in jiffies. */
> 	unsigned long emitted_jiffies;
> 
>diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
>index ff998ce..900a93c 100644
>--- a/drivers/gpu/drm/i915/i915_gem.c
>+++ b/drivers/gpu/drm/i915/i915_gem.c
>@@ -1785,19 +1785,20 @@ i915_add_request(struct intel_ring_buffer *ring,
> 	drm_i915_private_t *dev_priv = ring->dev->dev_private;
> 	uint32_t seqno;
> 	int was_empty;
>-	int ret;
>+	int acthd;
> 
> 	BUG_ON(request == NULL);
> 	seqno = i915_gem_next_request_seqno(ring);
> 
>-	ret = ring->add_request(ring, seqno);
>-	if (ret < 0)
>-	    return ret;
>+	acthd = ring->add_request(ring, seqno);
>+	if (acthd < 0)
>+	    return acthd;
> 
> 	trace_i915_gem_request_add(ring, seqno);
> 
> 	request->seqno = seqno;
> 	request->ring = ring;
>+	request->acthd = acthd;
> 	request->emitted_jiffies = jiffies;
> 	was_empty = list_empty(&ring->request_list);
> 	list_add_tail(&request->list, &ring->request_list);
>@@ -1962,6 +1963,7 @@ i915_gem_retire_requests_ring(struct intel_ring_buffer *ring)
> 			break;
> 
> 		trace_i915_gem_request_retire(ring, request->seqno);
>+		ring->last_retired_head = request->acthd;
> 
> 		list_del(&request->list);
> 		i915_gem_request_remove_from_client(request);
>diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
>index e53dd2d..255245b 100644
>--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
>+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
>@@ -1058,6 +1058,17 @@ int intel_wait_ring_buffer(struct intel_ring_buffer *ring, int n)
> 	struct drm_i915_private *dev_priv = dev->dev_private;
> 	unsigned long end;
> 
>+	i915_gem_retire_requests(dev);
>+
>+	if (ring->last_retired_head) {
>+		ring->head = ring->last_retired_head;
>+		ring->last_retired_head = 0;
>+
>+		ring->space = ring_space(ring);
>+		if (ring->space >= n)
>+			return 0;
>+	}
>+
> 	trace_i915_ring_wait_begin(ring);
> 	if (drm_core_check_feature(dev, DRIVER_GEM))
> 		/* With GEM the hangcheck timer should kick us out of the loop,
>diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
>index e1ded68..1921ce8 100644
>--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
>+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
>@@ -46,6 +46,8 @@ struct  intel_ring_buffer {
> 	int		effective_size;
> 	struct intel_hw_status_page status_page;
> 
>+	u32		last_retired_head;
>+
> 	spinlock_t	irq_lock;
> 	u32		irq_refcount;
> 	u32		irq_mask;
>-- 
>1.7.8.3
>

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Attachments on bug 45492: 56439 | 56445 | 56453 | 56463 | 56479 | 56480 | 56481 | 56522 | 56749 | 56750 | 56765

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