From patchwork Tue Mar 14 01:14:04 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: John Harrison X-Patchwork-Id: 13173513 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BA92DC6FD19 for ; Tue, 14 Mar 2023 01:15:05 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 93A7C10E15E; Tue, 14 Mar 2023 01:15:04 +0000 (UTC) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5337310E15E for ; Tue, 14 Mar 2023 01:15:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1678756502; x=1710292502; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=xxRJzM0tdIJWxLfW04QAE7vNroesWb1li65UDaIhYKI=; b=jAXKK4oq3N/Ex5bb98BEq0T9oVCqiK/qIiRBtGPqq45GqO9XccxO1WPg Zn3vqhxNJb2eltNhz7obc3nZNGMO4PT6Ycr6sYgbdWuk4uI/BaZMQobzl luOfdmoo6HMNELDHFBEpNwztczhov3rAAtnFt1lnVS+wSRHEvJnjdDOLS eMt/2uOcx5of2kOYvHMrf2PfAERde3+t5c6QgKsdvx6U+Do55lxSDJafS 0UQ0O0Xm9139lrp3gJbPkBOnmeCSoxWUDRkavrz22MZqu88PSu26Pt0U4 7ZUb3NMQARcy3P0go91lzLaIm4ZqKeYpObmfR756RopHz0V91b5tc3t/1 w==; X-IronPort-AV: E=McAfee;i="6500,9779,10648"; a="338846709" X-IronPort-AV: E=Sophos;i="5.98,258,1673942400"; d="scan'208";a="338846709" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Mar 2023 18:15:01 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10648"; a="672126074" X-IronPort-AV: E=Sophos;i="5.98,258,1673942400"; d="scan'208";a="672126074" Received: from relo-linux-5.jf.intel.com ([10.165.21.152]) by orsmga007.jf.intel.com with ESMTP; 13 Mar 2023 18:15:01 -0700 From: John.C.Harrison@Intel.com To: stable@vger.kernel.org Date: Mon, 13 Mar 2023 18:14:04 -0700 Message-Id: <20230314011404.1009812-1-John.C.Harrison@Intel.com> X-Mailer: git-send-email 2.39.1 In-Reply-To: <167820545815114@kroah.com> References: <167820545815114@kroah.com> MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH 4.14.y] drm/i915: Don't use BAR mappings for ring buffers with LLC X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jani Nikula , intel-gfx@lists.freedesktop.org, Chris Wilson , Rodrigo Vivi Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" From: John Harrison Direction from hardware is that ring buffers should never be mapped via the BAR on systems with LLC. There are too many caching pitfalls due to the way BAR accesses are routed. So it is safest to just not use it. Signed-off-by: John Harrison Fixes: 9d80841ea4c9 ("drm/i915: Allow ringbuffers to be bound anywhere") Cc: Chris Wilson Cc: Joonas Lahtinen Cc: Jani Nikula Cc: Rodrigo Vivi Cc: Tvrtko Ursulin Cc: intel-gfx@lists.freedesktop.org Cc: # v4.9+ Tested-by: Jouni Högander Reviewed-by: Daniele Ceraolo Spurio Link: https://patchwork.freedesktop.org/patch/msgid/20230216011101.1909009-3-John.C.Harrison@Intel.com (cherry picked from commit 65c08339db1ada87afd6cfe7db8e60bb4851d919) Signed-off-by: Jani Nikula (cherry picked from commit 85636167e3206c3fbd52254fc432991cc4e90194) --- drivers/gpu/drm/i915/intel_ringbuffer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c index 63667a5c2c87..6c7563c1ab5f 100644 --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -1314,7 +1314,7 @@ int intel_ring_pin(struct intel_ring *ring, if (unlikely(ret)) return ret; - if (i915_vma_is_map_and_fenceable(vma)) + if (i915_vma_is_map_and_fenceable(vma) && !HAS_LLC(vma->vm->i915)) addr = (void __force *)i915_vma_pin_iomap(vma); else addr = i915_gem_object_pin_map(vma->obj, map); @@ -1346,7 +1346,7 @@ void intel_ring_unpin(struct intel_ring *ring) /* Discard any unused bytes beyond that submitted to hw. */ intel_ring_reset(ring, ring->tail); - if (i915_vma_is_map_and_fenceable(ring->vma)) + if (i915_vma_is_map_and_fenceable(ring->vma) && !HAS_LLC(ring->vma->vm->i915)) i915_vma_unpin_iomap(ring->vma); else i915_gem_object_unpin_map(ring->vma->obj);