From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DCDDFC43381 for ; Wed, 20 Feb 2019 21:04:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A2C93214AF for ; Wed, 20 Feb 2019 21:04:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727403AbfBTVEG (ORCPT ); Wed, 20 Feb 2019 16:04:06 -0500 Received: from anholt.net ([50.246.234.109]:51876 "EHLO anholt.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727210AbfBTVEA (ORCPT ); Wed, 20 Feb 2019 16:04:00 -0500 Received: from localhost (localhost [127.0.0.1]) by anholt.net (Postfix) with ESMTP id 67DC310A2D1A; Wed, 20 Feb 2019 13:04:00 -0800 (PST) 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 ccMDZ6pZAjhx; Wed, 20 Feb 2019 13:03:57 -0800 (PST) Received: from eliezer.anholt.net (localhost [127.0.0.1]) by anholt.net (Postfix) with ESMTP id 2993710A2D22; Wed, 20 Feb 2019 13:03:46 -0800 (PST) Received: by eliezer.anholt.net (Postfix, from userid 1000) id AA42E2FE4651; Wed, 20 Feb 2019 13:03:43 -0800 (PST) From: Eric Anholt To: dri-devel@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org, Paul Kocialkowski , Maxime Ripard , Eric Anholt Subject: [PATCH 6/7] drm/vc4: Add helpers for pm get/put. Date: Wed, 20 Feb 2019 13:03:42 -0800 Message-Id: <20190220210343.28157-6-eric@anholt.net> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190220210343.28157-1-eric@anholt.net> References: <20190220210343.28157-1-eric@anholt.net> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This makes sure the vc4_reset doesn't hit an obscure race with the GET_PARAM ioctl, fixes a decrement outside of the lock, and prevents future code from making mistakes with the weird return value of pm_runtime_get_sync(). Signed-off-by: Eric Anholt --- drivers/gpu/drm/vc4/vc4_drv.c | 21 +++++++++------------ drivers/gpu/drm/vc4/vc4_drv.h | 2 ++ drivers/gpu/drm/vc4/vc4_gem.c | 21 +++++---------------- drivers/gpu/drm/vc4/vc4_v3d.c | 33 +++++++++++++++++++++++++++++++++ 4 files changed, 49 insertions(+), 28 deletions(-) diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c index de1d0ce11831..f95891a61d52 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.c +++ b/drivers/gpu/drm/vc4/vc4_drv.c @@ -77,28 +77,25 @@ static int vc4_get_param_ioctl(struct drm_device *dev, void *data, switch (args->param) { case DRM_VC4_PARAM_V3D_IDENT0: - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); - if (ret < 0) + ret = vc4_v3d_pm_get(vc4); + if (ret) return ret; args->value = V3D_READ(V3D_IDENT0); - pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); - pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); + vc4_v3d_pm_put(vc4); break; case DRM_VC4_PARAM_V3D_IDENT1: - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); - if (ret < 0) + ret = vc4_v3d_pm_get(vc4); + if (ret) return ret; args->value = V3D_READ(V3D_IDENT1); - pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); - pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); + vc4_v3d_pm_put(vc4); break; case DRM_VC4_PARAM_V3D_IDENT2: - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); - if (ret < 0) + ret = vc4_v3d_pm_get(vc4); + if (ret) return ret; args->value = V3D_READ(V3D_IDENT2); - pm_runtime_mark_last_busy(&vc4->v3d->pdev->dev); - pm_runtime_put_autosuspend(&vc4->v3d->pdev->dev); + vc4_v3d_pm_put(vc4); break; case DRM_VC4_PARAM_SUPPORTS_BRANCHES: case DRM_VC4_PARAM_SUPPORTS_ETC1: diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h index 495c5a13a948..c71988b270bc 100644 --- a/drivers/gpu/drm/vc4/vc4_drv.h +++ b/drivers/gpu/drm/vc4/vc4_drv.h @@ -809,6 +809,8 @@ void vc4_plane_async_set_fb(struct drm_plane *plane, /* vc4_v3d.c */ extern struct platform_driver vc4_v3d_driver; int vc4_v3d_get_bin_slot(struct vc4_dev *vc4); +int vc4_v3d_pm_get(struct vc4_dev *vc4); +void vc4_v3d_pm_put(struct vc4_dev *vc4); /* vc4_validate.c */ int diff --git a/drivers/gpu/drm/vc4/vc4_gem.c b/drivers/gpu/drm/vc4/vc4_gem.c index 8d816e5ed762..4544a478f106 100644 --- a/drivers/gpu/drm/vc4/vc4_gem.c +++ b/drivers/gpu/drm/vc4/vc4_gem.c @@ -969,12 +969,7 @@ vc4_complete_exec(struct drm_device *dev, struct vc4_exec_info *exec) /* Release the reference we had on the perf monitor. */ vc4_perfmon_put(exec->perfmon); - mutex_lock(&vc4->power_lock); - 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); + vc4_v3d_pm_put(vc4); kfree(exec); } @@ -1153,17 +1148,11 @@ vc4_submit_cl_ioctl(struct drm_device *dev, void *data, return -ENOMEM; } - mutex_lock(&vc4->power_lock); - if (vc4->power_refcount++ == 0) { - ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); - if (ret < 0) { - mutex_unlock(&vc4->power_lock); - vc4->power_refcount--; - kfree(exec); - return ret; - } + ret = vc4_v3d_pm_get(vc4); + if (ret) { + kfree(exec); + return ret; } - mutex_unlock(&vc4->power_lock); exec->args = args; INIT_LIST_HEAD(&exec->unref_list); diff --git a/drivers/gpu/drm/vc4/vc4_v3d.c b/drivers/gpu/drm/vc4/vc4_v3d.c index f008584eb739..7820b8eaaa98 100644 --- a/drivers/gpu/drm/vc4/vc4_v3d.c +++ b/drivers/gpu/drm/vc4/vc4_v3d.c @@ -124,6 +124,39 @@ static int vc4_v3d_debugfs_ident(struct seq_file *m, void *unused) return 0; } +/** + * Wraps pm_runtime_get_sync() in a refcount, so that we can reliably + * get the pm_runtime refcount to 0 in vc4_reset(). + */ +int +vc4_v3d_pm_get(struct vc4_dev *vc4) +{ + mutex_lock(&vc4->power_lock); + if (vc4->power_refcount++ == 0) { + int ret = pm_runtime_get_sync(&vc4->v3d->pdev->dev); + + if (ret < 0) { + vc4->power_refcount--; + mutex_unlock(&vc4->power_lock); + return ret; + } + } + mutex_unlock(&vc4->power_lock); + + return 0; +} + +void +vc4_v3d_pm_put(struct vc4_dev *vc4) +{ + mutex_lock(&vc4->power_lock); + 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); +} + static void vc4_v3d_init_hw(struct drm_device *dev) { struct vc4_dev *vc4 = to_vc4_dev(dev); -- 2.20.1