From patchwork Tue Aug 20 14:12:18 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 11103855 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C1D2F184E for ; Tue, 20 Aug 2019 14:12:54 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id AA3D7214DA for ; Tue, 20 Aug 2019 14:12:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AA3D7214DA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=chris-wilson.co.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=intel-gfx-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 23CCD6E80A; Tue, 20 Aug 2019 14:12:54 +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 A68676E80A for ; Tue, 20 Aug 2019 14:12:51 +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 18203224-1500050 for multiple; Tue, 20 Aug 2019 15:12:19 +0100 From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Tue, 20 Aug 2019 15:12:18 +0100 Message-Id: <20190820141218.14714-1-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.23.0.rc1 MIME-Version: 1.0 Subject: [Intel-gfx] [PATCH] drm/i915/gtt: Relax pd_used assertion 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" The current assertion tries to make sure that we do not over count the number of used PDE inside a page directory -- that is with an array of 512 pde, we do not expect more than 512 elements used! However, our assertion has to take into account that as we pin an element into the page directory, the caller first pins the page directory so the usage count is one higher. However, this should be one extra pin per thread, and the upper bound is that we may have one thread for each entry. Signed-off-by: Chris Wilson Cc: Mika Kuoppala Reviewed-by: Mika Kuoppala --- drivers/gpu/drm/i915/i915_gem_gtt.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index e48df11a19fb..9435d184ddf2 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -771,7 +771,8 @@ __set_pd_entry(struct i915_page_directory * const pd, struct i915_page_dma * const to, u64 (*encode)(const dma_addr_t, const enum i915_cache_level)) { - GEM_BUG_ON(atomic_read(px_used(pd)) > ARRAY_SIZE(pd->entry)); + /* Each thread pre-pins the pd, and we may have a thread per each pde */ + GEM_BUG_ON(atomic_read(px_used(pd)) > 2 * ARRAY_SIZE(pd->entry)); atomic_inc(px_used(pd)); pd->entry[idx] = to;