From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.codeaurora.org by pdx-caf-mail.web.codeaurora.org (Dovecot) with LMTP id EMTqE9vuGFs9AQAAmS7hNA ; Thu, 07 Jun 2018 08:37:47 +0000 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 409BB607F7; Thu, 7 Jun 2018 08:37:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on pdx-caf-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by smtp.codeaurora.org (Postfix) with ESMTP id A5ACC60452; Thu, 7 Jun 2018 08:37:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org A5ACC60452 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753503AbeFGIhn (ORCPT + 25 others); Thu, 7 Jun 2018 04:37:43 -0400 Received: from metis.ext.pengutronix.de ([85.220.165.71]:40575 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752568AbeFGIhj (ORCPT ); Thu, 7 Jun 2018 04:37:39 -0400 Received: from weser.hi.pengutronix.de ([2001:67c:670:100:fa0f:41ff:fe58:4010]) by metis.ext.pengutronix.de with esmtp (Exim 4.89) (envelope-from ) id 1fQqQK-0006Na-9v; Thu, 07 Jun 2018 10:37:36 +0200 Message-ID: <1528360654.15027.2.camel@pengutronix.de> Subject: Re: [PATCH 1/3 v2] drm/v3d: Take a lock across GPU scheduler job creation and queuing. From: Lucas Stach To: Eric Anholt , dri-devel@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org Date: Thu, 07 Jun 2018 10:37:34 +0200 In-Reply-To: <20180606174851.12433-1-eric@anholt.net> References: <1528274797.26063.6.camel@pengutronix.de> <20180606174851.12433-1-eric@anholt.net> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.22.6-1+deb9u1 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 2001:67c:670:100:fa0f:41ff:fe58:4010 X-SA-Exim-Mail-From: l.stach@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Mittwoch, den 06.06.2018, 10:48 -0700 schrieb Eric Anholt: > Between creation and queueing of a job, you need to prevent any other > job from being created and queued.  Otherwise the scheduler's fences > may be signaled out of seqno order. > > v2: move mutex unlock to the error label. > > > Signed-off-by: Eric Anholt > Fixes: 57692c94dcbe ("drm/v3d: Introduce a new DRM driver for Broadcom V3D V3.x+") Reviewed-by: Lucas Stach > --- >  drivers/gpu/drm/v3d/v3d_drv.h | 5 +++++ >  drivers/gpu/drm/v3d/v3d_gem.c | 4 ++++ >  2 files changed, 9 insertions(+) > > diff --git a/drivers/gpu/drm/v3d/v3d_drv.h b/drivers/gpu/drm/v3d/v3d_drv.h > index a043ac3aae98..26005abd9c5d 100644 > --- a/drivers/gpu/drm/v3d/v3d_drv.h > +++ b/drivers/gpu/drm/v3d/v3d_drv.h > @@ -85,6 +85,11 @@ struct v3d_dev { > >    */ > >   struct mutex reset_lock; >   > > + /* Lock taken when creating and pushing the GPU scheduler > > +  * jobs, to keep the sched-fence seqnos in order. > > +  */ > > + struct mutex sched_lock; > + > >   struct { > >   u32 num_allocated; > >   u32 pages_allocated; > diff --git a/drivers/gpu/drm/v3d/v3d_gem.c b/drivers/gpu/drm/v3d/v3d_gem.c > index b513f9189caf..269fe16379c0 100644 > --- a/drivers/gpu/drm/v3d/v3d_gem.c > +++ b/drivers/gpu/drm/v3d/v3d_gem.c > @@ -550,6 +550,7 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data, > >   if (ret) > >   goto fail; >   > > + mutex_lock(&v3d->sched_lock); > >   if (exec->bin.start != exec->bin.end) { > >   ret = drm_sched_job_init(&exec->bin.base, > >    &v3d->queue[V3D_BIN].sched, > @@ -576,6 +577,7 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data, > >   kref_get(&exec->refcount); /* put by scheduler job completion */ > >   drm_sched_entity_push_job(&exec->render.base, > >     &v3d_priv->sched_entity[V3D_RENDER]); > > + mutex_unlock(&v3d->sched_lock); >   > >   v3d_attach_object_fences(exec); >   > @@ -594,6 +596,7 @@ v3d_submit_cl_ioctl(struct drm_device *dev, void *data, > >   return 0; >   >  fail_unreserve: > > + mutex_unlock(&v3d->sched_lock); > >   v3d_unlock_bo_reservations(dev, exec, &acquire_ctx); >  fail: > >   v3d_exec_put(exec); > @@ -615,6 +618,7 @@ v3d_gem_init(struct drm_device *dev) > >   spin_lock_init(&v3d->job_lock); > >   mutex_init(&v3d->bo_lock); > >   mutex_init(&v3d->reset_lock); > > + mutex_init(&v3d->sched_lock); >   > >   /* Note: We don't allocate address 0.  Various bits of HW > >    * treat 0 as special, such as the occlusion query counters