From patchwork Fri Nov 4 23:32:38 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Anholt X-Patchwork-Id: 9413521 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 3EBE66022E for ; Fri, 4 Nov 2016 23:32:44 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 311B0285B6 for ; Fri, 4 Nov 2016 23:32:44 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 25BFC2B2C8; Fri, 4 Nov 2016 23:32:44 +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 80D36285B6 for ; Fri, 4 Nov 2016 23:32:43 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 42F5B6E0DD; Fri, 4 Nov 2016 23:32:42 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from anholt.net (anholt.net [50.246.234.109]) by gabe.freedesktop.org (Postfix) with ESMTP id 8545D6E0DD for ; Fri, 4 Nov 2016 23:32:40 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by anholt.net (Postfix) with ESMTP id C667B10A1E6F; Sat, 5 Nov 2016 00:37:01 -0700 (PDT) X-Virus-Scanned: Debian amavisd-new at anholt.net Received: from anholt.net ([127.0.0.1]) by localhost (kingsolver.anholt.net [127.0.0.1]) (amavisd-new, port 10024) with LMTP id dIRwAm6GM1Uh; Sat, 5 Nov 2016 00:37:00 -0700 (PDT) Received: from eliezer.anholt.net (localhost [127.0.0.1]) by anholt.net (Postfix) with ESMTP id C79FB10A1CAB; Sat, 5 Nov 2016 00:37:00 -0700 (PDT) Received: by eliezer.anholt.net (Postfix, from userid 1000) id 9A6ED2E026D; Fri, 4 Nov 2016 16:32:38 -0700 (PDT) From: Eric Anholt To: dri-devel@lists.freedesktop.org Subject: [PATCH] drm/vc4: Use runtime autosuspend to avoid thrashing V3D power state. Date: Fri, 4 Nov 2016 16:32:38 -0700 Message-Id: <20161104233238.20773-1-eric@anholt.net> X-Mailer: git-send-email 2.10.2 Cc: linux-kernel@vger.kernel.org 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: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP The pm_runtime_put() we were using immediately released power on the device, which meant that we were generally turning the device off and on once per frame. In many profiles I've looked at, that added up to about 1% of CPU time, but this could get worse in the case of frequent rendering and readback (as may happen in X rendering). By keeping the device on until we've been idle for a couple of frames, we drop the overhead of runtime PM down to sub-.1%. Signed-off-by: Eric Anholt --- drivers/gpu/drm/vc4/vc4_drv.c | 9 ++++++--- drivers/gpu/drm/vc4/vc4_gem.c | 6 ++++-- drivers/gpu/drm/vc4/vc4_v3d.c | 2 ++ 3 files changed, 12 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index b087404c2784..7abfe088f2d1 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -61,21 +61,24 @@ static int vc4_get_param_ioctl(struct drm_device *dev, void *data, if (ret < 0) return ret; args->value = V3D_READ(V3D_IDENT0); - pm_runtime_put(&vc4->v3d->pdev->dev); + pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); + pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); break; case DRM_VC4_PARAM_V3D_IDENT1: ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); if (ret < 0) return ret; args->value = V3D_READ(V3D_IDENT1); - pm_runtime_put(&vc4->v3d->pdev->dev); + pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); + pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); break; case DRM_VC4_PARAM_V3D_IDENT2: ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); if (ret < 0) return ret; args->value = V3D_READ(V3D_IDENT2); - pm_runtime_put(&vc4->v3d->pdev->dev); + pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); + pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); break; case DRM_VC4_PARAM_SUPPORTS_BRANCHES: case DRM_VC4_PARAM_SUPPORTS_ETC1: diff --git a/drivers/gpu/drm/vc4/vc4_gem.c b/drivers/gpu/drm/vc4/vc4_gem.c index 303f23c96220..db920771bfb5 100644 --- a/drivers/gpu/drm/vc4/vc4_gem.c +++ b/drivers/gpu/drm/vc4/vc4_gem.c @@ -709,8 +709,10 @@ vc4_complete_exec(struct drm_device *dev, struct vc4_exec_info *exec) } mutex_lock(&vc4->power_lock); - if (--vc4->power_refcount == 0) - pm_runtime_put(&vc4->v3d->pdev->dev); + if (--vc4->power_refcount == 0) { + pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); + pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); + } mutex_unlock(&vc4->power_lock); kfree(exec); diff --git a/drivers/gpu/drm/vc4/vc4_v3d.c b/drivers/gpu/drm/vc4/vc4_v3d.c index e6d3c6028341..7cc346ad9b0b 100644 --- a/drivers/gpu/drm/vc4/vc4_v3d.c +++ b/drivers/gpu/drm/vc4/vc4_v3d.c @@ -222,6 +222,8 @@ static int vc4_v3d_bind(struct device *dev, struct device *master, void *data) return ret; } + pm_runtime_use_autosuspend(dev); + pm_runtime_set_autosuspend_delay(dev, 40); /* a little over 2 frames. */ pm_runtime_enable(dev); return 0;