Attachment 97221 Details for Bug 75502 – Reorder semaphore deadlock detection

[patch] Reorder semaphore deadlock detection

0001-drm-i915-Reorder-semaphore-deadlock-check.patch (text/plain), 1.62 KB, created by Chris Wilson on 2014-04-11 12:49:41 UTC

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Creator: Chris Wilson

Created: 2014-04-11 12:49:41 UTC

Size: 1.62 KB

patch

obsolete

>From f0cd9176976b40b85a72b1048f0e60b6a4263077 Mon Sep 17 00:00:00 2001
>From: Chris Wilson <chris@chris-wilson.co.uk>
>Date: Fri, 11 Apr 2014 13:42:05 +0100
>Subject: [PATCH] drm/i915: Reorder semaphore deadlock check
>
>If a semaphore is waiting on another ring, which in turn happens to be
>waiting on the first ring, but that second semaphore has been signalled,
>we will kick the second ring and so can treat the first ring as a valid
>WAIT and not as HUNG.
>
>References: https://bugs.freedesktop.org/show_bug.cgi?id=75502
>Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
>---
> drivers/gpu/drm/i915/i915_irq.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
>index f21ebfc..3e0c559 100644
>--- a/drivers/gpu/drm/i915/i915_irq.c
>+++ b/drivers/gpu/drm/i915/i915_irq.c
>@@ -2616,7 +2616,7 @@ static int semaphore_passed(struct intel_ring_buffer *ring)
> 	ring->hangcheck.deadlock = true;
> 
> 	signaller = semaphore_waits_for(ring, &seqno);
>-	if (signaller == NULL || signaller->hangcheck.deadlock)
>+	if (signaller == NULL)
> 		return -1;
> 
> 	/* cursory check for an unkickable deadlock */
>@@ -2624,7 +2624,13 @@ static int semaphore_passed(struct intel_ring_buffer *ring)
> 	if (ctl & RING_WAIT_SEMAPHORE && semaphore_passed(signaller) < 0)
> 		return -1;
> 
>-	return i915_seqno_passed(signaller->get_seqno(signaller, false), seqno);
>+	if (i915_seqno_passed(signaller->get_seqno(signaller, false), seqno))
>+		return 1;
>+
>+	if (signaller->hangcheck.deadlock)
>+		return -1;
>+
>+	return 0;
> }
> 
> static void semaphore_clear_deadlocks(struct drm_i915_private *dev_priv)
>-- 
>1.9.0
>

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Attachments on bug 75502: 94724 | 94763 | 94883 | 95088 | 95792 | 95793 | 97218 | 97221 | 98285 | 98614

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