From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757627AbaHHUpt (ORCPT ); Fri, 8 Aug 2014 16:45:49 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:40356 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757571AbaHHUpV (ORCPT ); Fri, 8 Aug 2014 16:45:21 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Chris Wilson , Mika Kuoppala , Jani Nikula , Daniel Vetter , Kamal Mostafa Subject: [PATCH 3.13 168/259] drm/i915: Reorder the semaphore deadlock check, again Date: Fri, 8 Aug 2014 13:39:51 -0700 Message-Id: <1407530482-4483-169-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1407530482-4483-1-git-send-email-kamal@canonical.com> References: <1407530482-4483-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.13.11.6 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Chris Wilson commit a0d036b074b4a5a933e37fcb9bdd6b3cc80a0387 upstream. commit 4be173813e57c7298103a83155c2391b5b167b4c Author: Chris Wilson Date: Fri Jun 6 10:22:29 2014 +0100 drm/i915: Reorder semaphore deadlock check did the majority of the work, but it missed one crucial detail: The check for the unkickable deadlock on this ring must come after the check whether the ring that we are waiting on has already passed its target seqno. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=80709 Tested-by: Stefan Huber Signed-off-by: Chris Wilson Cc: Mika Kuoppala Cc: Jani Nikula Signed-off-by: Daniel Vetter Signed-off-by: Kamal Mostafa --- drivers/gpu/drm/i915/i915_irq.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c index 2093c72..3a10da2 100644 --- a/drivers/gpu/drm/i915/i915_irq.c +++ b/drivers/gpu/drm/i915/i915_irq.c @@ -2392,7 +2392,7 @@ static int semaphore_passed(struct intel_ring_buffer *ring) { struct drm_i915_private *dev_priv = ring->dev->dev_private; struct intel_ring_buffer *signaller; - u32 seqno, ctl; + u32 seqno; ring->hangcheck.deadlock++; @@ -2404,15 +2404,12 @@ static int semaphore_passed(struct intel_ring_buffer *ring) if (signaller->hangcheck.deadlock >= I915_NUM_RINGS) return -1; - /* cursory check for an unkickable deadlock */ - ctl = I915_READ_CTL(signaller); - if (ctl & RING_WAIT_SEMAPHORE && semaphore_passed(signaller) < 0) - return -1; - if (i915_seqno_passed(signaller->get_seqno(signaller, false), seqno)) return 1; - if (signaller->hangcheck.deadlock) + /* cursory check for an unkickable deadlock */ + if (I915_READ_CTL(signaller) & RING_WAIT_SEMAPHORE && + semaphore_passed(signaller) < 0) return -1; return 0; -- 1.9.1