From patchwork Mon Jan 11 10:45:02 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 8001461 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 [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 8A6239F1C0 for ; Mon, 11 Jan 2016 10:48:04 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id C8F9E20279 for ; Mon, 11 Jan 2016 10:48:03 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id EB22620219 for ; Mon, 11 Jan 2016 10:48:02 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id BA9466E2E9; Mon, 11 Jan 2016 02:48:01 -0800 (PST) X-Original-To: intel-gfx@lists.freedesktop.org Delivered-To: intel-gfx@lists.freedesktop.org Received: from mail-wm0-f66.google.com (mail-wm0-f66.google.com [74.125.82.66]) by gabe.freedesktop.org (Postfix) with ESMTPS id BED0E6E2D0 for ; Mon, 11 Jan 2016 02:47:03 -0800 (PST) Received: by mail-wm0-f66.google.com with SMTP id b14so25704031wmb.1 for ; Mon, 11 Jan 2016 02:47:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=NiZU5TnaBZASRNZVXDbAqBUXTub5ElWOuGhiXwjVY4c=; b=NaB0UZHz24iJD/59Da6/PUzI1LTcomGQEX+HBxvoMVgUBfssg8w4gMJo2gRbt0Sujn nsmGQkEeS5WlOBK8IgCEvFC/qcMR9Nfazhn4MsjozM5dhqfMkWBIIB0MZjK1MpziFjjg m59fwZmE8Y+Alpvi3KHiZpw5+oWDMm3MBbieC7QeFyl4esp8GGMw4qoiGPEfgZ7tQFoF LIuehEVrZAWB2xoVq2C6JqTLdbvSRXUuGu5AYTUyH2iqGm2Rsst4T23hs2BTGa4Ke03E S+5dfp3Ql5ELC1X0uNldGZRJcqI0RelLOKK/mkJ8mhs5MaiTFazdCly+Oqz07bszBDYD 7ngw== X-Received: by 10.194.133.164 with SMTP id pd4mr2606108wjb.133.1452509222598; Mon, 11 Jan 2016 02:47:02 -0800 (PST) Received: from haswell.alporthouse.com ([78.156.65.138]) by smtp.gmail.com with ESMTPSA id t3sm118879383wjz.11.2016.01.11.02.47.01 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 11 Jan 2016 02:47:01 -0800 (PST) From: Chris Wilson To: intel-gfx@lists.freedesktop.org Date: Mon, 11 Jan 2016 10:45:02 +0000 Message-Id: <1452509174-16671-32-git-send-email-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.7.0.rc3 In-Reply-To: <1452509174-16671-1-git-send-email-chris@chris-wilson.co.uk> References: <1452503961-14837-1-git-send-email-chris@chris-wilson.co.uk> <1452509174-16671-1-git-send-email-chris@chris-wilson.co.uk> Subject: [Intel-gfx] [PATCH 118/190] drm/i915: Remove locking for get_tiling 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: , MIME-Version: 1.0 Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" X-Spam-Status: No, score=-4.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,RP_MATCHES_RCVD,T_DKIM_INVALID,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 Since we are not concerned with userspace racing itself with set-tiling (the order is indeterminant even if we take a lock), then we can safely read back the single obj->tiling_mode and do the static lookup of swizzle mode without having to take a lock. get-tiling is reasonably frequent due to the back-channel passing around of tiling parameters in DRI2/DRI3. Signed-off-by: Chris Wilson --- drivers/gpu/drm/i915/i915_gem_tiling.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c index c7588135a82d..387246f19ce2 100644 --- a/drivers/gpu/drm/i915/i915_gem_tiling.c +++ b/drivers/gpu/drm/i915/i915_gem_tiling.c @@ -301,10 +301,8 @@ i915_gem_get_tiling(struct drm_device *dev, void *data, if (&obj->base == NULL) return -ENOENT; - mutex_lock(&dev->struct_mutex); - args->tiling_mode = obj->tiling_mode; - switch (obj->tiling_mode) { + switch (args->tiling_mode) { case I915_TILING_X: args->swizzle_mode = dev_priv->mm.bit_6_swizzle_x; break; @@ -328,8 +326,6 @@ i915_gem_get_tiling(struct drm_device *dev, void *data, if (args->swizzle_mode == I915_BIT_6_SWIZZLE_9_10_17) args->swizzle_mode = I915_BIT_6_SWIZZLE_9_10; - drm_gem_object_unreference(&obj->base); - mutex_unlock(&dev->struct_mutex); - + drm_gem_object_unreference_unlocked(&obj->base); return 0; }