From patchwork Fri Jul 18 09:19:40 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rodrigo Vivi X-Patchwork-Id: 4586471 Return-Path: X-Original-To: patchwork-intel-gfx@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 25E689F26C for ; Fri, 18 Jul 2014 16:18:50 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 31C542018E for ; Fri, 18 Jul 2014 16:18:49 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 082CA20142 for ; Fri, 18 Jul 2014 16:18:47 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 882056E182; Fri, 18 Jul 2014 09:18:46 -0700 (PDT) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id B4E856E182 for ; Fri, 18 Jul 2014 09:18:45 -0700 (PDT) Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga101.jf.intel.com with ESMTP; 18 Jul 2014 09:18:30 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.01,686,1400050800"; d="scan'208";a="575264204" Received: from di-604.jf.intel.com (HELO rdvivi-hillsboro.jf.intel.com) ([10.7.201.28]) by orsmga002.jf.intel.com with ESMTP; 18 Jul 2014 09:18:30 -0700 From: Rodrigo Vivi To: intel-gfx@lists.freedesktop.org Date: Fri, 18 Jul 2014 02:19:40 -0700 Message-Id: <1405675180-12374-1-git-send-email-rodrigo.vivi@intel.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <20140718161240.GE31263@strange.amr.corp.intel.com> References: <20140718161240.GE31263@strange.amr.corp.intel.com> Cc: Ben Widawsky , Rodrigo Vivi Subject: [Intel-gfx] [PATCH] drm/i915: Fix possible overflow when recording semaphore states. X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Spam-Status: No, score=-2.7 required=5.0 tests=BAYES_00, DATE_IN_PAST_06_12, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP semaphore _sync_seqno, _seqno and _mbox are smaller than number of rings. This optimization is to remove the ring itself from the list and the logic to do that is at intel_ring_sync_index as below: /* * rcs -> 0 = vcs, 1 = bcs, 2 = vecs, 3 = vcs2; * vcs -> 0 = bcs, 1 = vecs, 2 = vcs2, 3 = rcs; * bcs -> 0 = vecs, 1 = vcs2. 2 = rcs, 3 = vcs; * vecs -> 0 = vcs2, 1 = rcs, 2 = vcs, 3 = bcs; * vcs2 -> 0 = rcs, 1 = vcs, 2 = bcs, 3 = vecs; */ v2: Skip when from == to (Damien). v3: avoid computing idx when from == to (Damien). use ring == to instead of ring->id == to->id (Damien). use continue instead of return (Rodrigo). v4: avoid all unecessary computation (Damien). reduce idx to loop scope (Damien). Cc: Damien Lespiau Cc: Ben Widawsky Signed-off-by: Rodrigo Vivi Reviewed-by: Ben Widawsky --- drivers/gpu/drm/i915/i915_gpu_error.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c index 9faebbc..0b3f694 100644 --- a/drivers/gpu/drm/i915/i915_gpu_error.c +++ b/drivers/gpu/drm/i915/i915_gpu_error.c @@ -764,7 +764,7 @@ static void gen8_record_semaphore_state(struct drm_i915_private *dev_priv, struct intel_engine_cs *ring, struct drm_i915_error_ring *ering) { - struct intel_engine_cs *useless; + struct intel_engine_cs *to; int i; if (!i915_semaphore_is_enabled(dev_priv->dev)) @@ -776,13 +776,20 @@ static void gen8_record_semaphore_state(struct drm_i915_private *dev_priv, dev_priv->semaphore_obj, &dev_priv->gtt.base); - for_each_ring(useless, dev_priv, i) { - u16 signal_offset = - (GEN8_SIGNAL_OFFSET(ring, i) & PAGE_MASK) / 4; - u32 *tmp = error->semaphore_obj->pages[0]; + for_each_ring(to, dev_priv, i) { + int idx; + u16 signal_offset; + u32 *tmp; - ering->semaphore_mboxes[i] = tmp[signal_offset]; - ering->semaphore_seqno[i] = ring->semaphore.sync_seqno[i]; + if (ring == to) + continue; + + signal_offset = (GEN8_SIGNAL_OFFSET(ring, i) & PAGE_MASK) / 4; + tmp = error->semaphore_obj->pages[0]; + idx = intel_ring_sync_index(ring, to); + + ering->semaphore_mboxes[idx] = tmp[signal_offset]; + ering->semaphore_seqno[idx] = ring->semaphore.sync_seqno[idx]; } }