From patchwork Fri Aug 17 08:24:05 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 10568523 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9E12813B6 for ; Fri, 17 Aug 2018 08:24:21 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 91D4C2B59E for ; Fri, 17 Aug 2018 08:24:21 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 844592B5A2; Fri, 17 Aug 2018 08:24:21 +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=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, 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 1A9462B59E for ; Fri, 17 Aug 2018 08:24:21 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2D1AA6E030; Fri, 17 Aug 2018 08:24:20 +0000 (UTC) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from fireflyinternet.com (mail.fireflyinternet.com [109.228.58.192]) by gabe.freedesktop.org (Postfix) with ESMTPS id 34AB06E030 for ; Fri, 17 Aug 2018 08:24:18 +0000 (UTC) X-Default-Received-SPF: pass (skip=forwardok (res=PASS)) x-ip-name=78.156.65.138; Received: from haswell.alporthouse.com (unverified [78.156.65.138]) by fireflyinternet.com (Firefly Internet (M1)) with ESMTP id 12977921-1500050 for multiple; Fri, 17 Aug 2018 09:24:09 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Fri, 17 Aug 2018 09:24:05 +0100 Message-Id: <20180817082405.755-1-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH] drm/i915: Keep physical cursors pinned while in use X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.23 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 The optimisation inherent in commit 6a2c4232ece1 ("drm/i915: Make the physical object coherent with GTT") relies on that once we allocated a cursor we would have coherent, zero overhead access to the scanout plane holding the cursor. That is we could then do the very frequent cursor updates X enjoys with no indirection or kernel involvement. However, that all hinges on the GGTT mmap of the cursor being pinned and not require refaulting on each access -- handling such a page fault likely requires the busy GGTT to be rearranged causing a stall. A very simple fix is then to handle the physical cursor exactly like other cursors and keep its vma pinned while active. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=107600 References: 6a2c4232ece1 ("drm/i915: Make the physical object coherent with GTT") Signed-off-by: Chris Wilson Cc: Ville Syrjälä Reviewed-by: Ville Syrjälä --- drivers/gpu/drm/i915/intel_display.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 592b847db88e..d47ec9fd4af4 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -12966,8 +12966,11 @@ static int intel_plane_pin_fb(struct intel_plane_state *plane_state) INTEL_INFO(dev_priv)->cursor_needs_physical) { struct drm_i915_gem_object *obj = intel_fb_obj(fb); const int align = intel_cursor_alignment(dev_priv); + int err; - return i915_gem_object_attach_phys(obj, align); + err = i915_gem_object_attach_phys(obj, align); + if (err) + return err; } vma = intel_pin_and_fence_fb_obj(fb,