From patchwork Sun Apr 5 15:40:21 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Chris Wilson X-Patchwork-Id: 6162401 Return-Path: X-Original-To: patchwork-dri-devel@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 866CF9F2EC for ; Sun, 5 Apr 2015 15:41:15 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9CF442040F for ; Sun, 5 Apr 2015 15:41:14 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 1EFC5203AD for ; Sun, 5 Apr 2015 15:41:13 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1A74F6E2C1; Sun, 5 Apr 2015 08:41:11 -0700 (PDT) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from relay.fireflyinternet.com (hostedrelay.fireflyinternet.com [109.228.30.76]) by gabe.freedesktop.org (Postfix) with ESMTP id 1A5736E2C1 for ; Sun, 5 Apr 2015 08:41:08 -0700 (PDT) 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 relay.fireflyinternet.com (FireflyRelay1) with ESMTP id 422956-1305619 for multiple; Sun, 05 Apr 2015 16:40:34 +0100 From: Chris Wilson To: dri-devel@lists.freedesktop.org Subject: [PATCH 2/2] drm: Shortcircuit vblank queries Date: Sun, 5 Apr 2015 16:40:21 +0100 Message-Id: <1428248421-29641-2-git-send-email-chris@chris-wilson.co.uk> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1428248421-29641-1-git-send-email-chris@chris-wilson.co.uk> References: <1427974453-10633-1-git-send-email-chris@chris-wilson.co.uk> <1428248421-29641-1-git-send-email-chris@chris-wilson.co.uk> MIME-Version: 1.0 X-Authenticated-User: chris.alporthouse@surfanytime.net Cc: =?UTF-8?q?Michel=20D=C3=A4nzer?= , Laurent Pinchart , Dave Airlie X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD,UNPARSEABLE_RELAY autolearn=ham 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 Bypass all the spinlocks and return the last timestamp and counter from the last vblank if the driver delcares that it is accurate (and stable across on/off), and the vblank is currently enabled. Signed-off-by: Chris Wilson Cc: Ville Syrjälä Cc: Daniel Vetter Cc: Michel Dänzer Cc: Laurent Pinchart Cc: Dave Airlie , Cc: Mario Kleiner --- drivers/gpu/drm/drm_irq.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index ba80b51b4b00..be9c210bb22e 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -1538,6 +1538,17 @@ err_put: return ret; } +static bool drm_wait_vblank_is_query(union drm_wait_vblank *vblwait) +{ + if (vblwait->request.sequence) + return false; + + return _DRM_VBLANK_RELATIVE == + (vblwait->request.type & (_DRM_VBLANK_TYPES_MASK | + _DRM_VBLANK_EVENT | + _DRM_VBLANK_NEXTONMISS)); +} + /* * Wait for VBLANK. * @@ -1587,6 +1598,21 @@ int drm_wait_vblank(struct drm_device *dev, void *data, vblank = &dev->vblank[crtc]; + /* If the counter is currently enabled and accurate, short-circuit queries + * to return the cached timestamp of the last vblank. + */ + if (dev->vblank_disable_immediate && + drm_wait_vblank_is_query(vblwait) && + vblank->enabled) { + struct timeval now; + + vblwait->reply.sequence = + drm_vblank_count_and_time(dev, crtc, &now); + vblwait->reply.tval_sec = now.tv_sec; + vblwait->reply.tval_usec = now.tv_usec; + return 0; + } + ret = drm_vblank_get(dev, crtc); if (ret) { DRM_DEBUG("failed to acquire vblank counter, %d\n", ret);