From patchwork Wed Nov 30 02:17:23 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Wang, Zhi A" X-Patchwork-Id: 9453483 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 5C5316074E for ; Wed, 30 Nov 2016 02:25:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4792D28173 for ; Wed, 30 Nov 2016 02:25:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3C179281A7; Wed, 30 Nov 2016 02:25:17 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D26F928173 for ; Wed, 30 Nov 2016 02:25:16 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 708DB6E878; Wed, 30 Nov 2016 02:25:15 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9C32F6E878 for ; Wed, 30 Nov 2016 02:25:13 +0000 (UTC) Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga102.fm.intel.com with ESMTP; 29 Nov 2016 18:25:13 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,719,1473145200"; d="scan'208";a="37204091" Received: from dev-inno.bj.intel.com ([10.238.135.53]) by fmsmga006.fm.intel.com with ESMTP; 29 Nov 2016 18:25:11 -0800 From: Zhi Wang To: intel-gfx@lists.freedesktop.org Date: Wed, 30 Nov 2016 10:17:23 +0800 Message-Id: <1480472243-26256-1-git-send-email-zhi.a.wang@intel.com> X-Mailer: git-send-email 1.9.1 MIME-Version: 1.0 Cc: Zhiyuan Lv Subject: [Intel-gfx] [PATCH v2] drm/i915: Move the release of PT page to the upper caller X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Virus-Scanned: ClamAV using ClamSMTP a PT page will be released if it doesn't contain any meaningful mappings during PPGTT page table shrinking. The PT entry in the upper level will be set to a scratch entry. Normally this works nicely, but in virtualization world, the PPGTT page table is tracked by hypervisor. Releasing the PT page before modifying the upper level PT entry would cause extra efforts. As the tracked page has been returned to OS before losing track from hypervisor, it could be written in any pattern. Hypervisor has to recognize if a page is still being used as a PT page by validating these writing patterns. It's complicated. Better let the guest modify the PT entry in upper level PT first, then release the PT page. v2: Tvrtko: - Reuse struct drm_i915_private * as much as possible in functions. Reviewed-by: Chris Wilson v1 Reviewed-by: Michał Winiarski v1 Cc: Tvrtko Ursulin Cc: Michał Winiarski Cc: Michel Thierry Cc: Joonas Lahtinen Cc: Chris Wilson Cc: Zhenyu Wang Cc: Zhiyuan Lv Signed-off-by: Zhi Wang --- drivers/gpu/drm/i915/i915_gem_gtt.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index b4bde14..e788d22 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -736,10 +736,8 @@ static bool gen8_ppgtt_clear_pt(struct i915_address_space *vm, bitmap_clear(pt->used_ptes, pte, num_entries); - if (bitmap_empty(pt->used_ptes, GEN8_PTES)) { - free_pt(to_i915(vm->dev), pt); + if (bitmap_empty(pt->used_ptes, GEN8_PTES)) return true; - } pt_vaddr = kmap_px(pt); @@ -775,13 +773,12 @@ static bool gen8_ppgtt_clear_pd(struct i915_address_space *vm, pde_vaddr = kmap_px(pd); pde_vaddr[pde] = scratch_pde; kunmap_px(ppgtt, pde_vaddr); + free_pt(to_i915(vm->dev), pt); } } - if (bitmap_empty(pd->used_pdes, I915_PDES)) { - free_pd(to_i915(vm->dev), pd); + if (bitmap_empty(pd->used_pdes, I915_PDES)) return true; - } return false; } @@ -813,16 +810,14 @@ static bool gen8_ppgtt_clear_pdp(struct i915_address_space *vm, pdpe_vaddr[pdpe] = scratch_pdpe; kunmap_px(ppgtt, pdpe_vaddr); } + free_pd(dev_priv, pd); } } mark_tlbs_dirty(ppgtt); - if (USES_FULL_48BIT_PPGTT(dev_priv) && - bitmap_empty(pdp->used_pdpes, I915_PDPES_PER_PDP(dev_priv))) { - free_pdp(dev_priv, pdp); + if (bitmap_empty(pdp->used_pdpes, I915_PDPES_PER_PDP(dev_priv))) return true; - } return false; } @@ -854,6 +849,7 @@ static void gen8_ppgtt_clear_pml4(struct i915_address_space *vm, pml4e_vaddr = kmap_px(pml4); pml4e_vaddr[pml4e] = scratch_pml4e; kunmap_px(ppgtt, pml4e_vaddr); + free_pdp(to_i915(vm->dev), pdp); } } }