Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752337AbcDZOxM (ORCPT ); Tue, 26 Apr 2016 10:53:12 -0400 Received: from mail-wm0-f66.google.com ([74.125.82.66]:36670 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751950AbcDZOxK (ORCPT ); Tue, 26 Apr 2016 10:53:10 -0400 Date: Tue, 26 Apr 2016 16:53:05 +0200 From: Daniel Vetter To: Gustavo Padovan Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, devel@driverdev.osuosl.org, dri-devel@lists.freedesktop.org, Daniel Stone , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Riley Andrews , Daniel Vetter , Rob Clark , Greg Hackmann , John Harrison , Maarten Lankhorst , Sumit Semwal , Gustavo Padovan Subject: Re: [RFC v2 8/8] drm/fence: add out-fences support Message-ID: <20160426145305.GY8291@phenom.ffwll.local> Mail-Followup-To: Gustavo Padovan , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, devel@driverdev.osuosl.org, dri-devel@lists.freedesktop.org, Daniel Stone , Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Riley Andrews , Rob Clark , Greg Hackmann , John Harrison , Maarten Lankhorst , Sumit Semwal , Gustavo Padovan References: <1461623608-29538-1-git-send-email-gustavo@padovan.org> <1461623608-29538-9-git-send-email-gustavo@padovan.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1461623608-29538-9-git-send-email-gustavo@padovan.org> X-Operating-System: Linux phenom 4.6.0-rc5+ User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10517 Lines: 348 On Mon, Apr 25, 2016 at 07:33:28PM -0300, Gustavo Padovan wrote: > From: Gustavo Padovan > > Support DRM out-fences creating a sync_file with a fence for each crtc > update with the DRM_MODE_ATOMIC_OUT_FENCE flag. > > We then send an struct drm_out_fences array with the out-fences fds back in > the drm_atomic_ioctl() as an out arg in the out_fences_ptr field. > > struct drm_out_fences { > __u32 crtc_id; > __u32 fd; > }; > > v2: Comment by Rob Clark: > - Squash commit that adds DRM_MODE_ATOMIC_OUT_FENCE flag here. > > Comment by Daniel Vetter: > - Add clean up code for out_fences > > Signed-off-by: Gustavo Padovan > --- > drivers/gpu/drm/drm_atomic.c | 163 +++++++++++++++++++++++++++++++++++++++++-- > include/drm/drm_crtc.h | 10 +++ > include/uapi/drm/drm_mode.h | 11 ++- > 3 files changed, 179 insertions(+), 5 deletions(-) > > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c > index 5f9d434..06c6007 100644 > --- a/drivers/gpu/drm/drm_atomic.c > +++ b/drivers/gpu/drm/drm_atomic.c > @@ -1566,6 +1566,133 @@ void drm_atomic_clean_old_fb(struct drm_device *dev, > } > EXPORT_SYMBOL(drm_atomic_clean_old_fb); > > +static struct drm_out_fence_state *get_out_fence(struct drm_device *dev, > + struct drm_atomic_state *state, > + uint32_t __user *out_fences_ptr, > + uint64_t count_out_fences, > + uint64_t user_data) > +{ > + struct drm_crtc *crtc; > + struct drm_crtc_state *crtc_state; > + struct drm_out_fences *out_fences; > + struct drm_out_fence_state *fence_state; > + int num_fences = 0; > + int i, ret; > + > + if (count_out_fences > dev->mode_config.num_crtc) > + return ERR_PTR(-EINVAL); > + > + out_fences = kcalloc(count_out_fences, sizeof(*out_fences), > + GFP_KERNEL); > + if (!out_fences) > + return ERR_PTR(-ENOMEM); A bit tricky, but the above kcalloc is the only thing that catches integer overflows in count_out_fences. Needs a comment imo since this could be a security exploit if we accidentally screw it up. Also needs a testcase imo. > + > + fence_state = kcalloc(count_out_fences, sizeof(*fence_state), > + GFP_KERNEL); > + if (!fence_state) { > + kfree(out_fences); > + return ERR_PTR(-ENOMEM); > + } > + > + for (i = 0 ; i < count_out_fences ; i++) > + fence_state[i].fd = -1; > + > + for_each_crtc_in_state(state, crtc, crtc_state, i) { > + struct drm_pending_vblank_event *e; > + struct fence *fence; > + char name[32]; > + > + fence = kzalloc(sizeof(*fence), GFP_KERNEL); > + if (!fence) { > + ret = -ENOMEM; > + goto out; > + } > + > + fence_init(fence, &drm_crtc_fence_ops, &crtc->fence_lock, > + crtc->fence_context, crtc->fence_seqno); > + > + snprintf(name, sizeof(name), "crtc-%d_%lu", > + drm_crtc_index(crtc), crtc->fence_seqno++); Hm ... fence_init_with_name? I'm kinda confused why we only name fences that are exported though, and why not all of them. Debugging fence deadlocks is real hard, so giving them all names might be a good idea. Anyway, seems like more room for a bit more sync_file/struct fence merging. > + > + fence_state[i].fd = get_unused_fd_flags(O_CLOEXEC); > + if (fence_state[i].fd < 0) { > + fence_put(fence); > + ret = fence_state[i].fd; > + goto out; > + } > + > + fence_state[i].sync_file = sync_file_create(name, fence); > + if(!fence_state[i].sync_file) { > + fence_put(fence); > + ret = -ENOMEM; > + goto out; > + } > + > + if (crtc_state->event) { > + crtc_state->event->base.fence = fence; > + } else { This looks a bit funny - I'd change the create event logic to create an event either if we have the either drm event or out-fence flag set. > + e = create_vblank_event(dev, NULL, fence, user_data); > + if (!e) { > + ret = -ENOMEM; > + goto out; > + } > + > + crtc_state->event = e; > + } > + > + out_fences[num_fences].crtc_id = crtc->base.id; > + out_fences[num_fences].fd = fence_state[i].fd; > + num_fences++; > + } > + > + if (copy_to_user(out_fences_ptr, out_fences, > + num_fences * sizeof(*out_fences))) { > + ret = -EFAULT; > + goto out; > + } > + > + kfree(out_fences); > + > + return fence_state; > + > +out: > + for (i = 0 ; i < count_out_fences ; i++) { > + if (fence_state[i].sync_file) > + sync_file_put(fence_state[i].sync_file); > + if (fence_state[i].fd >= 0) > + put_unused_fd(fence_state[i].fd); > + } > + > + kfree(fence_state); > + kfree(out_fences); > + > + return ERR_PTR(ret); > +} > + > +static void install_out_fence(uint64_t count_out_fences, > + struct drm_out_fence_state *state) > +{ > + int i; > + > + for (i = 0 ; i < count_out_fences ; i++) { > + if (state[i].sync_file) > + sync_file_install(state[i].sync_file, state[i].fd); Is sync_file_install anything more than fd_install? Imo a wrapper for just that function is overkill and just hides stuff. I'd nuke it (another sync_file patch though). In dma-buf we also don't wrap it, we only have a convenience wrapper for users who want to combine the get_unused_flags+fd_install in one go. And maybe even that is silly. Ok, I unlazied and it's indeed just a silly wrapper. Please nuke it. > + } > +} > + > +static void release_out_fence(uint64_t count_out_fences, > + struct drm_out_fence_state *state) > +{ > + int i; > + > + for (i = 0 ; i < count_out_fences ; i++) { > + if (state->sync_file) > + sync_file_put(state->sync_file); > + if (state->fd >= 0) > + put_unused_fd(state->fd); > + } > +} > + > int drm_mode_atomic_ioctl(struct drm_device *dev, > void *data, struct drm_file *file_priv) > { > @@ -1574,12 +1701,14 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, > uint32_t __user *count_props_ptr = (uint32_t __user *)(unsigned long)(arg->count_props_ptr); > uint32_t __user *props_ptr = (uint32_t __user *)(unsigned long)(arg->props_ptr); > uint64_t __user *prop_values_ptr = (uint64_t __user *)(unsigned long)(arg->prop_values_ptr); > + uint32_t __user *out_fences_ptr = (uint32_t __user *)(unsigned long)(arg->out_fences_ptr); > unsigned int copied_objs, copied_props; > struct drm_atomic_state *state; > struct drm_modeset_acquire_ctx ctx; > struct drm_plane *plane; > struct drm_crtc *crtc; > struct drm_crtc_state *crtc_state; > + struct drm_out_fence_state *fence_state = NULL; > unsigned plane_mask; > int ret = 0; > unsigned int i, j; > @@ -1605,9 +1734,13 @@ int drm_mode_atomic_ioctl(struct drm_device *dev, > !dev->mode_config.async_page_flip) > return -EINVAL; > > + if ((arg->flags & DRM_MODE_ATOMIC_OUT_FENCE) && !arg->count_out_fences) > + return -EINVAL; We need testcases which check that arg->count_out_fences and arg->out_fences are 0 when the OUT_FENCE flag is not set. Definitely needs an igt testcase for this invalid input case. Ofc we also need tests that give the kernel nonsens in count_out_fences and out_fences with the flag set. > + > /* can't test and expect an event at the same time. */ > if ((arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) && > - (arg->flags & DRM_MODE_PAGE_FLIP_EVENT)) > + (arg->flags & (DRM_MODE_PAGE_FLIP_EVENT > + | DRM_MODE_ATOMIC_OUT_FENCE))) If you go with my suggestion above to create the event if either is set, maybe a DRM_MODE_ATOMIC_EVENT_MASK with both? Would read easier. > return -EINVAL; > > drm_modeset_acquire_init(&ctx, 0); > @@ -1699,16 +1832,30 @@ retry: > } > } > > + if (arg->flags & DRM_MODE_ATOMIC_OUT_FENCE) { > + fence_state = get_out_fence(dev, state, out_fences_ptr, > + arg->count_out_fences, > + arg->user_data); > + if (IS_ERR(fence_state)) { > + ret = PTR_ERR(fence_state); > + goto out; > + } > + } > + > if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) { > /* > * Unlike commit, check_only does not clean up state. > * Below we call drm_atomic_state_free for it. > */ > ret = drm_atomic_check_only(state); > - } else if (arg->flags & DRM_MODE_ATOMIC_NONBLOCK) { > - ret = drm_atomic_async_commit(state); > } else { > - ret = drm_atomic_commit(state); > + if (arg->flags & DRM_MODE_ATOMIC_OUT_FENCE) > + install_out_fence(arg->count_out_fences, fence_state); > + > + if (arg->flags & DRM_MODE_ATOMIC_NONBLOCK) > + ret = drm_atomic_async_commit(state); > + else > + ret = drm_atomic_commit(state); > } > > out: > @@ -1729,6 +1876,14 @@ out: > } > } > > + if ((arg->flags & DRM_MODE_ATOMIC_OUT_FENCE) && > + !IS_ERR_OR_NULL(fence_state)) { > + if (ret) > + release_out_fence(arg->count_out_fences, fence_state); > + > + kfree(fence_state); > + } > + > if (ret == -EDEADLK) { > drm_atomic_state_clear(state); > drm_modeset_backoff(&ctx); > diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h > index d8c32c8..5f7c272 100644 > --- a/include/drm/drm_crtc.h > +++ b/include/drm/drm_crtc.h > @@ -798,6 +798,16 @@ static inline struct drm_crtc *fence_to_crtc(struct fence *fence) > } > > /** > + * struct drm_out_fence_state - store out_fence data for clean up > + * @sync_file: sync_file related to the out_fence > + * @fd: file descriptor to installed on the sync_file. > + */ > +struct drm_out_fence_state { > + struct sync_file *sync_file; > + int fd; > +}; > + > +/** > * struct drm_connector_state - mutable connector state > * @connector: backpointer to the connector > * @crtc: CRTC to connect connector to, NULL if disabled > diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h > index 7a7856e..4cdcd22 100644 > --- a/include/uapi/drm/drm_mode.h > +++ b/include/uapi/drm/drm_mode.h > @@ -582,13 +582,20 @@ struct drm_mode_destroy_dumb { > #define DRM_MODE_ATOMIC_TEST_ONLY 0x0100 > #define DRM_MODE_ATOMIC_NONBLOCK 0x0200 > #define DRM_MODE_ATOMIC_ALLOW_MODESET 0x0400 > +#define DRM_MODE_ATOMIC_OUT_FENCE 0x0800 > > #define DRM_MODE_ATOMIC_FLAGS (\ > DRM_MODE_PAGE_FLIP_EVENT |\ > DRM_MODE_PAGE_FLIP_ASYNC |\ > DRM_MODE_ATOMIC_TEST_ONLY |\ > DRM_MODE_ATOMIC_NONBLOCK |\ > - DRM_MODE_ATOMIC_ALLOW_MODESET) > + DRM_MODE_ATOMIC_ALLOW_MODESET |\ > + DRM_MODE_ATOMIC_OUT_FENCE) > + > +struct drm_out_fences { > + __u32 crtc_id; > + __u32 fd; > +}; > > struct drm_mode_atomic { > __u32 flags; > @@ -599,6 +606,8 @@ struct drm_mode_atomic { > __u64 prop_values_ptr; > __u64 reserved; > __u64 user_data; > + __u64 count_out_fences; > + __u64 out_fences_ptr; > }; > > /** > -- > 2.5.5 > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch