Attachment 56481 Details for Bug 45492 – Keep using request->head until we run out of requests

[patch] Keep using request->head until we run out of requests

0001-drm-i915-Prefer-the-ring-last_retired_head-whilst-we.patch (text/plain), 2.91 KB, created by Chris Wilson on 2012-02-01 15:40:34 UTC

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Creator: Chris Wilson

Created: 2012-02-01 15:40:34 UTC

Size: 2.91 KB

patch

obsolete

>From d2d1f99d2a6a55380438043b7bcf7b443bdcb775 Mon Sep 17 00:00:00 2001
>From: Chris Wilson <chris@chris-wilson.co.uk>
>Date: Wed, 1 Feb 2012 23:32:19 +0000
>Subject: [PATCH] drm/i915: Prefer the ring->last_retired_head whilst we
> having pending requests
>
>Closes a race with reading ACTHD directly with requests outstanding.
>This is the less fugly version.
>
>Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
>---
> drivers/gpu/drm/i915/i915_drv.h         |    2 ++
> drivers/gpu/drm/i915/i915_gem.c         |    2 +-
> drivers/gpu/drm/i915/intel_ringbuffer.c |   25 ++++++++++++++++++-------
> 3 files changed, 21 insertions(+), 8 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
>index b26e951..96c6f66 100644
>--- a/drivers/gpu/drm/i915/i915_drv.h
>+++ b/drivers/gpu/drm/i915/i915_drv.h
>@@ -1237,6 +1237,8 @@ i915_gem_object_unpin_fence(struct drm_i915_gem_object *obj)
> }
> 
> void i915_gem_retire_requests(struct drm_device *dev);
>+void i915_gem_retire_requests_ring(struct intel_ring_buffer *ring);
>+
> void i915_gem_reset(struct drm_device *dev);
> void i915_gem_clflush_object(struct drm_i915_gem_object *obj);
> int __must_check i915_gem_object_set_domain(struct drm_i915_gem_object *obj,
>diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
>index 900a93c..d2e0fac 100644
>--- a/drivers/gpu/drm/i915/i915_gem.c
>+++ b/drivers/gpu/drm/i915/i915_gem.c
>@@ -1935,7 +1935,7 @@ void i915_gem_reset(struct drm_device *dev)
> /**
>  * This function clears the request list as sequence numbers are passed.
>  */
>-static void
>+void
> i915_gem_retire_requests_ring(struct intel_ring_buffer *ring)
> {
> 	uint32_t seqno;
>diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
>index 255245b..f4f643e 100644
>--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
>+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
>@@ -1058,8 +1058,6 @@ 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;
>@@ -1081,11 +1079,24 @@ int intel_wait_ring_buffer(struct intel_ring_buffer *ring, int n)
> 		end = jiffies + 3 * HZ;
> 
> 	do {
>-		ring->head = I915_READ_HEAD(ring);
>-		ring->space = ring_space(ring);
>-		if (ring->space >= n) {
>-			trace_i915_ring_wait_end(ring);
>-			return 0;
>+		if (!list_empty(&ring->request_list)) {
>+			i915_gem_retire_requests_ring(ring);
>+
>+			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;
>+			}
>+		} else {
>+			ring->head = I915_READ_HEAD(ring);
>+			ring->space = ring_space(ring);
>+			if (ring->space >= n) {
>+				trace_i915_ring_wait_end(ring);
>+				return 0;
>+			}
> 		}
> 
> 		if (dev->primary->master) {
>-- 
>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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