2016-11-11 05:16:23

by Gustavo Padovan

[permalink] [raw]
Subject: [PATCH v8 0/3] drm: add explict fencing

From: Gustavo Padovan <[email protected]>

Hi,

New version of the DRM fences patches with all comments on v7 adressed. Please
refer to the cover letter[1] in a previous version to check for more details.

The changes since the last version can be seen in commit message on each patch.

Robert Foss managed to port Android's drm_hwcomposer to the new HWC2 API and
added support to fences. Current patches can be seen here:

https://git.collabora.com/cgit/user/robertfoss/drm_hwcomposer.git/log/?h=hwc2_fence_v1

He ran AOSP on top of padovan/fences kernel branch with full fence support on
qemu/virgl and msm db410c. That means we already have a working open source
userspace using the explicit fencing implementation.

Also i-g-t testing are available with all tests suggested in v7 included:

https://git.collabora.com/cgit/user/padovan/intel-gpu-tools.git/log/

Please review!

Gustavo

[1] https://www.mail-archive.com/[email protected]/msg1253822.html

---
Gustavo Padovan (3):
drm/fence: add in-fences support
drm/fence: add fence timeline to drm_crtc
drm/fence: add out-fences support

drivers/gpu/drm/Kconfig | 1 +
drivers/gpu/drm/drm_atomic.c | 256 +++++++++++++++++++++++++++++-------
drivers/gpu/drm/drm_atomic_helper.c | 5 +
drivers/gpu/drm/drm_crtc.c | 45 +++++++
drivers/gpu/drm/drm_plane.c | 1 +
include/drm/drm_atomic.h | 1 +
include/drm/drm_crtc.h | 56 ++++++++
7 files changed, 320 insertions(+), 45 deletions(-)

--
2.5.5


2016-11-11 05:16:29

by Gustavo Padovan

[permalink] [raw]
Subject: [PATCH v8 1/3] drm/fence: add in-fences support

From: Gustavo Padovan <[email protected]>

There is now a new property called IN_FENCE_FD attached to every plane
state that receives sync_file fds from userspace via the atomic commit
IOCTL.

The fd is then translated to a fence (that may be a fence_array
subclass or just a normal fence) and then used by DRM to fence_wait() for
all fences in the sync_file to signal. So it only commits when all
framebuffers are ready to scanout.

v2: Comments by Daniel Vetter:
- remove set state->fence = NULL in destroy phase
- accept fence -1 as valid and just return 0
- do not call fence_get() - sync_file_fences_get() already calls it
- fence_put() if state->fence is already set, in case userspace
set the property more than once.

v3: WARN_ON if fence is set but state has no FB

v4: Comment from Maarten Lankhorst
- allow set fence with no related fb

v5: rename FENCE_FD to IN_FENCE_FD

v6: Comments by Daniel Vetter:
- rename plane_state->in_fence back to "fence"
- re-introduce WARN_ON if fence set but no fb

- rebase after fence -> dma_fence rename

v7: Comments by Brian Starkey
- set state->fence to NULL when duplicating the state
- fail if IN_FENCE_FD was already set

Signed-off-by: Gustavo Padovan <[email protected]>
---
drivers/gpu/drm/Kconfig | 1 +
drivers/gpu/drm/drm_atomic.c | 14 ++++++++++++++
drivers/gpu/drm/drm_atomic_helper.c | 5 +++++
drivers/gpu/drm/drm_crtc.c | 6 ++++++
drivers/gpu/drm/drm_plane.c | 1 +
include/drm/drm_crtc.h | 5 +++++
6 files changed, 32 insertions(+)

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index 25e8e37..360cb92 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -12,6 +12,7 @@ menuconfig DRM
select I2C
select I2C_ALGOBIT
select DMA_SHARED_BUFFER
+ select SYNC_FILE
help
Kernel-level support for the Direct Rendering Infrastructure (DRI)
introduced in XFree86 4.0. If you say Y here, you need to select
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index b096c16..8e26ad1 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -31,6 +31,7 @@
#include <drm/drm_mode.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_print.h>
+#include <linux/sync_file.h>

#include "drm_crtc_internal.h"

@@ -709,6 +710,17 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
drm_atomic_set_fb_for_plane(state, fb);
if (fb)
drm_framebuffer_unreference(fb);
+ } else if (property == config->prop_in_fence_fd) {
+ if (state->fence)
+ return -EINVAL;
+
+ if (U642I64(val) == -1)
+ return 0;
+
+ state->fence = sync_file_get_fence(val);
+ if (!state->fence)
+ return -EINVAL;
+
} else if (property == config->prop_crtc_id) {
struct drm_crtc *crtc = drm_crtc_find(dev, val);
return drm_atomic_set_crtc_for_plane(state, crtc);
@@ -770,6 +782,8 @@ drm_atomic_plane_get_property(struct drm_plane *plane,

if (property == config->prop_fb_id) {
*val = (state->fb) ? state->fb->base.id : 0;
+ } else if (property == config->prop_in_fence_fd) {
+ *val = -1;
} else if (property == config->prop_crtc_id) {
*val = (state->crtc) ? state->crtc->base.id : 0;
} else if (property == config->prop_crtc_x) {
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 75ad01d..caed870 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -3076,6 +3076,8 @@ void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane,

if (state->fb)
drm_framebuffer_reference(state->fb);
+
+ state->fence = NULL;
}
EXPORT_SYMBOL(__drm_atomic_helper_plane_duplicate_state);

@@ -3114,6 +3116,9 @@ void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state)
{
if (state->fb)
drm_framebuffer_unreference(state->fb);
+
+ if (state->fence)
+ dma_fence_put(state->fence);
}
EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state);

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index ce274ed..154e040 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -397,6 +397,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
return -ENOMEM;
dev->mode_config.prop_fb_id = prop;

+ prop = drm_property_create_signed_range(dev, DRM_MODE_PROP_ATOMIC,
+ "IN_FENCE_FD", -1, INT_MAX);
+ if (!prop)
+ return -ENOMEM;
+ dev->mode_config.prop_in_fence_fd = prop;
+
prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
"CRTC_ID", DRM_MODE_OBJECT_CRTC);
if (!prop)
diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
index 249c0ae..3957ef8 100644
--- a/drivers/gpu/drm/drm_plane.c
+++ b/drivers/gpu/drm/drm_plane.c
@@ -137,6 +137,7 @@ int drm_universal_plane_init(struct drm_device *dev, struct drm_plane *plane,

if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
drm_object_attach_property(&plane->base, config->prop_fb_id, 0);
+ drm_object_attach_property(&plane->base, config->prop_in_fence_fd, -1);
drm_object_attach_property(&plane->base, config->prop_crtc_id, 0);
drm_object_attach_property(&plane->base, config->prop_crtc_x, 0);
drm_object_attach_property(&plane->base, config->prop_crtc_y, 0);
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 8cca2a8..11780a9 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -1214,6 +1214,11 @@ struct drm_mode_config {
*/
struct drm_property *prop_fb_id;
/**
+ * @prop_in_fence_fd: Sync File fd representing the incoming fences
+ * for a Plane.
+ */
+ struct drm_property *prop_in_fence_fd;
+ /**
* @prop_crtc_id: Default atomic plane property to specify the
* &drm_crtc.
*/
--
2.5.5

2016-11-11 05:16:42

by Gustavo Padovan

[permalink] [raw]
Subject: [PATCH v8 3/3] drm/fence: add out-fences support

From: Gustavo Padovan <[email protected]>

Support DRM out-fences by creating a sync_file with a fence for each CRTC
that sets the OUT_FENCE_PTR property.

We use the out_fence pointer received in the OUT_FENCE_PTR prop to send
the sync_file fd back to userspace.

The sync_file and fd are allocated/created before commit, but the
fd_install operation only happens after we know that commit succeed.

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

v3: Comments by Daniel Vetter:
- create DRM_MODE_ATOMIC_EVENT_MASK
- userspace should fill out_fences_ptr with the crtc_ids for which
it wants fences back.

v4: Create OUT_FENCE_PTR properties and remove old approach.

v5: Comments by Brian Starkey:
- Remove extra fence_get() in atomic_ioctl()
- Check ret before iterating on the crtc_state
- check ret before fd_install
- set fence_state to NULL at the beginning
- check fence_state->out_fence_ptr before put_user()
- change order of fput() and put_unused_fd() on failure

- Add access_ok() check to the out_fence_ptr received
- Rebase after fence -> dma_fence rename
- Store out_fence_ptr in the drm_atomic_state
- Split crtc_setup_out_fence()
- return -1 as out_fence with TEST_ONLY flag

v6: Comments by Daniel Vetter
- Add prepare/unprepare_crtc_signaling()
- move struct drm_out_fence_state to drm_atomic.c
- mark get_crtc_fence() as static

Comments by Brian Starkey
- proper set fence_ptr fence_state array
- isolate fence_idx increment

- improve error handling

v7: Comments by Daniel Vetter
- remove prefix from internal functions
- make out_fence_ptr an s64 pointer
- degrade DRM_INFO to DRM_DEBUG_ATOMIC when put_user fail
- fix doc issues
- filter out OUT_FENCE_PTR == NULL and do fail in this case
- add complete_crtc_signalling()
- krealloc fence_state on demand

Comment by Brian Starkey
- remove unused crtc_state arg from get_out_fence()

Signed-off-by: Gustavo Padovan <[email protected]>
---
drivers/gpu/drm/drm_atomic.c | 242 +++++++++++++++++++++++++++++++++++--------
drivers/gpu/drm/drm_crtc.c | 8 ++
include/drm/drm_atomic.h | 1 +
include/drm/drm_crtc.h | 6 ++
4 files changed, 212 insertions(+), 45 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 8e26ad1..cd39f13 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -290,6 +290,23 @@ drm_atomic_get_crtc_state(struct drm_atomic_state *state,
}
EXPORT_SYMBOL(drm_atomic_get_crtc_state);

+static void set_out_fence_for_crtc(struct drm_atomic_state *state,
+ struct drm_crtc *crtc, u64 __user *fence_ptr)
+{
+ state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = fence_ptr;
+}
+
+static u64 __user * get_out_fence_for_crtc(struct drm_atomic_state *state,
+ struct drm_crtc *crtc)
+{
+ u64 __user *fence_ptr;
+
+ fence_ptr = state->crtcs[drm_crtc_index(crtc)].out_fence_ptr;
+ state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = NULL;
+
+ return fence_ptr;
+}
+
/**
* drm_atomic_set_mode_for_crtc - set mode for CRTC
* @state: the CRTC whose incoming state to update
@@ -491,6 +508,16 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
&replaced);
state->color_mgmt_changed |= replaced;
return ret;
+ } else if (property == config->prop_out_fence_ptr) {
+ s64 __user *fence_ptr = u64_to_user_ptr(val);
+
+ if (!fence_ptr)
+ return 0;
+
+ if (!access_ok(VERIFY_WRITE, fence_ptr, sizeof(*fence_ptr)))
+ return -EFAULT;
+
+ set_out_fence_for_crtc(state->state, crtc, fence_ptr);
} else if (crtc->funcs->atomic_set_property)
return crtc->funcs->atomic_set_property(crtc, state, property, val);
else
@@ -533,6 +560,8 @@ drm_atomic_crtc_get_property(struct drm_crtc *crtc,
*val = (state->ctm) ? state->ctm->base.id : 0;
else if (property == config->gamma_lut_property)
*val = (state->gamma_lut) ? state->gamma_lut->base.id : 0;
+ else if (property == config->prop_out_fence_ptr)
+ *val = 0;
else if (crtc->funcs->atomic_get_property)
return crtc->funcs->atomic_get_property(crtc, state, property, val);
else
@@ -1659,11 +1688,9 @@ int drm_atomic_debugfs_init(struct drm_minor *minor)
*/

static struct drm_pending_vblank_event *create_vblank_event(
- struct drm_device *dev, struct drm_file *file_priv,
- struct dma_fence *fence, uint64_t user_data)
+ struct drm_device *dev, uint64_t user_data)
{
struct drm_pending_vblank_event *e = NULL;
- int ret;

e = kzalloc(sizeof *e, GFP_KERNEL);
if (!e)
@@ -1673,17 +1700,6 @@ static struct drm_pending_vblank_event *create_vblank_event(
e->event.base.length = sizeof(e->event);
e->event.user_data = user_data;

- if (file_priv) {
- ret = drm_event_reserve_init(dev, file_priv, &e->base,
- &e->event.base);
- if (ret) {
- kfree(e);
- return NULL;
- }
- }
-
- e->base.fence = fence;
-
return e;
}

@@ -1788,6 +1804,166 @@ void drm_atomic_clean_old_fb(struct drm_device *dev,
}
EXPORT_SYMBOL(drm_atomic_clean_old_fb);

+static struct dma_fence *get_crtc_fence(struct drm_crtc *crtc)
+{
+ struct dma_fence *fence;
+
+ fence = kzalloc(sizeof(*fence), GFP_KERNEL);
+ if (!fence)
+ return NULL;
+
+ dma_fence_init(fence, &drm_crtc_fence_ops, &crtc->fence_lock,
+ crtc->fence_context, ++crtc->fence_seqno);
+
+ return fence;
+}
+
+struct drm_out_fence_state {
+ s64 __user *out_fence_ptr;
+ struct sync_file *sync_file;
+ int fd;
+};
+
+static int setup_out_fence(struct drm_out_fence_state *fence_state,
+ struct dma_fence *fence)
+{
+ fence_state->fd = get_unused_fd_flags(O_CLOEXEC);
+ if (fence_state->fd < 0)
+ return fence_state->fd;
+
+ if (put_user(fence_state->fd, fence_state->out_fence_ptr))
+ return -EFAULT;
+
+ fence_state->sync_file = sync_file_create(fence);
+ if(!fence_state->sync_file)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int prepare_crtc_signaling(struct drm_device *dev,
+ struct drm_atomic_state *state,
+ struct drm_mode_atomic *arg,
+ struct drm_file *file_priv,
+ struct drm_out_fence_state **fence_state,
+ unsigned int *num_fences)
+{
+ struct drm_crtc *crtc;
+ struct drm_crtc_state *crtc_state;
+ int i, ret;
+
+ for_each_crtc_in_state(state, crtc, crtc_state, i) {
+ u64 __user *fence_ptr;
+
+ fence_ptr = get_out_fence_for_crtc(crtc_state->state, crtc);
+
+ if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY && fence_ptr) {
+ if (put_user(-1, fence_ptr))
+ return -EFAULT;
+
+ continue;
+ }
+
+ if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT || fence_ptr) {
+ struct drm_pending_vblank_event *e;
+
+ e = create_vblank_event(dev, arg->user_data);
+ if (!e)
+ return -ENOMEM;
+
+ crtc_state->event = e;
+ }
+
+ if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
+ struct drm_pending_vblank_event *e = crtc_state->event;
+
+ if (!file_priv)
+ continue;
+
+ ret = drm_event_reserve_init(dev, file_priv, &e->base,
+ &e->event.base);
+ if (ret) {
+ kfree(e);
+ crtc_state->event = NULL;
+ return ret;
+ }
+ }
+
+ if (fence_ptr) {
+ struct dma_fence *fence;
+ struct drm_out_fence_state *f;
+
+ f = krealloc(*fence_state, sizeof(**fence_state) *
+ (*num_fences + 1), GFP_KERNEL);
+ if (!f)
+ return -ENOMEM;
+
+ f[*num_fences].out_fence_ptr = fence_ptr;
+
+ fence = get_crtc_fence(crtc);
+ if (!fence)
+ return -ENOMEM;
+
+ ret = setup_out_fence(&f[*num_fences], fence);
+ if (ret) {
+ dma_fence_put(fence);
+ return ret;
+ }
+
+ (*num_fences)++;
+
+ *fence_state = f;
+ crtc_state->event->base.fence = fence;
+ }
+ }
+
+ return 0;
+}
+
+static void complete_crtc_signaling(struct drm_device *dev,
+ struct drm_atomic_state *state,
+ struct drm_out_fence_state *fence_state,
+ unsigned int num_fences, int ret)
+{
+ struct drm_crtc *crtc;
+ struct drm_crtc_state *crtc_state;
+ int i;
+
+ if (!ret) {
+ for (i = 0; i < num_fences; i++)
+ fd_install(fence_state[i].fd,
+ fence_state[i].sync_file->file);
+ return;
+ }
+
+ if (!fence_state)
+ return;
+
+ for_each_crtc_in_state(state, crtc, crtc_state, i) {
+ /*
+ * TEST_ONLY and PAGE_FLIP_EVENT are mutually
+ * exclusive, if they weren't, this code should be
+ * called on success for TEST_ONLY too.
+ */
+ if (crtc_state->event)
+ drm_event_cancel_free(dev, &crtc_state->event->base);
+ }
+
+ for (i = 0; i < num_fences; i++) {
+ if (fence_state[i].sync_file)
+ fput(fence_state[i].sync_file->file);
+ if (fence_state[i].fd >= 0)
+ put_unused_fd(fence_state[i].fd);
+
+ /* If this fails log error to the user */
+ if (fence_state[i].out_fence_ptr &&
+ put_user(-1, fence_state[i].out_fence_ptr))
+ DRM_DEBUG_ATOMIC("Couldn't clear out_fence_ptr\n");
+ }
+
+ kfree(fence_state);
+}
+
int drm_mode_atomic_ioctl(struct drm_device *dev,
void *data, struct drm_file *file_priv)
{
@@ -1800,11 +1976,10 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
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;
+ unsigned int i, j, num_fences = 0;

/* disallow for drivers not supporting atomic: */
if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
@@ -1919,20 +2094,10 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
drm_mode_object_unreference(obj);
}

- if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
- for_each_crtc_in_state(state, crtc, crtc_state, i) {
- struct drm_pending_vblank_event *e;
-
- e = create_vblank_event(dev, file_priv, NULL,
- arg->user_data);
- if (!e) {
- ret = -ENOMEM;
- goto out;
- }
-
- crtc_state->event = e;
- }
- }
+ ret = prepare_crtc_signaling(dev, state, arg, file_priv, &fence_state,
+ &num_fences);
+ if (ret)
+ goto out;

if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) {
/*
@@ -1952,20 +2117,7 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
out:
drm_atomic_clean_old_fb(dev, plane_mask, ret);

- if (ret && arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
- /*
- * TEST_ONLY and PAGE_FLIP_EVENT are mutually exclusive,
- * if they weren't, this code should be called on success
- * for TEST_ONLY too.
- */
-
- for_each_crtc_in_state(state, crtc, crtc_state, i) {
- if (!crtc_state->event)
- continue;
-
- drm_event_cancel_free(dev, &crtc_state->event->base);
- }
- }
+ complete_crtc_signaling(dev, state, fence_state, num_fences, ret);

if (ret == -EDEADLK) {
drm_atomic_state_clear(state);
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 9b9881b..e8bc1ae 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -274,6 +274,8 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
drm_object_attach_property(&crtc->base, config->prop_active, 0);
drm_object_attach_property(&crtc->base, config->prop_mode_id, 0);
+ drm_object_attach_property(&crtc->base,
+ config->prop_out_fence_ptr, 0);
}

return 0;
@@ -434,6 +436,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
return -ENOMEM;
dev->mode_config.prop_in_fence_fd = prop;

+ prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
+ "OUT_FENCE_PTR", 0, U64_MAX);
+ if (!prop)
+ return -ENOMEM;
+ dev->mode_config.prop_out_fence_ptr = prop;
+
prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
"CRTC_ID", DRM_MODE_OBJECT_CRTC);
if (!prop)
diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
index 331bb10..c0eaec7 100644
--- a/include/drm/drm_atomic.h
+++ b/include/drm/drm_atomic.h
@@ -144,6 +144,7 @@ struct __drm_crtcs_state {
struct drm_crtc *ptr;
struct drm_crtc_state *state;
struct drm_crtc_commit *commit;
+ s64 __user *out_fence_ptr;
};

struct __drm_connnectors_state {
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 0870de1..44571bc 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -1264,6 +1264,12 @@ struct drm_mode_config {
*/
struct drm_property *prop_in_fence_fd;
/**
+ * @prop_out_fence_ptr: Sync File fd pointer representing the
+ * outgoing fences for a CRTC. Userspace should provide a pointer to a
+ * value of type s64, and then cast that pointer to u64.
+ */
+ struct drm_property *prop_out_fence_ptr;
+ /**
* @prop_crtc_id: Default atomic plane property to specify the
* &drm_crtc.
*/
--
2.5.5

2016-11-11 05:16:32

by Gustavo Padovan

[permalink] [raw]
Subject: [PATCH v8 2/3] drm/fence: add fence timeline to drm_crtc

From: Gustavo Padovan <[email protected]>

Create one timeline context for each CRTC to be able to handle out-fences
and signal them. It adds a few members to struct drm_crtc: fence_context,
where we store the context we get from fence_context_alloc(), the
fence seqno and the fence lock, that we pass in fence_init() to be
used by the fence.

v2: Comment by Daniel Stone:
- add BUG_ON() to fence_to_crtc() macro

v3: Comment by Ville Syrjälä
- Use more meaningful name as crtc timeline name

v4: Comments by Brian Starkey
- Use even more meaninful name for the crtc timeline
- add doc for timeline_name
Comment by Daniel Vetter
- use in-line style for comments

- rebase after fence -> dma_fence rename

v5: Comment by Daniel Vetter
- Add doc for drm_crtc_fence_ops

Signed-off-by: Gustavo Padovan <[email protected]>
Reviewed-by: Daniel Vetter <[email protected]>
---
drivers/gpu/drm/drm_crtc.c | 31 +++++++++++++++++++++++++++++++
include/drm/drm_crtc.h | 45 +++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 76 insertions(+)

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 154e040..9b9881b 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -165,6 +165,32 @@ static void drm_crtc_crc_fini(struct drm_crtc *crtc)
#endif
}

+static const char *drm_crtc_fence_get_driver_name(struct dma_fence *fence)
+{
+ struct drm_crtc *crtc = fence_to_crtc(fence);
+
+ return crtc->dev->driver->name;
+}
+
+static const char *drm_crtc_fence_get_timeline_name(struct dma_fence *fence)
+{
+ struct drm_crtc *crtc = fence_to_crtc(fence);
+
+ return crtc->timeline_name;
+}
+
+static bool drm_crtc_fence_enable_signaling(struct dma_fence *fence)
+{
+ return true;
+}
+
+const struct dma_fence_ops drm_crtc_fence_ops = {
+ .get_driver_name = drm_crtc_fence_get_driver_name,
+ .get_timeline_name = drm_crtc_fence_get_timeline_name,
+ .enable_signaling = drm_crtc_fence_enable_signaling,
+ .wait = dma_fence_default_wait,
+};
+
/**
* drm_crtc_init_with_planes - Initialise a new CRTC object with
* specified primary and cursor planes.
@@ -222,6 +248,11 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
return -ENOMEM;
}

+ crtc->fence_context = dma_fence_context_alloc(1);
+ spin_lock_init(&crtc->fence_lock);
+ snprintf(crtc->timeline_name, sizeof(crtc->timeline_name),
+ "CRTC:%d-%s", crtc->base.id, crtc->name);
+
crtc->base.properties = &crtc->properties;

list_add_tail(&crtc->head, &config->crtc_list);
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 11780a9..0870de1 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -32,6 +32,8 @@
#include <linux/fb.h>
#include <linux/hdmi.h>
#include <linux/media-bus-format.h>
+#include <linux/srcu.h>
+#include <linux/dma-fence.h>
#include <uapi/drm/drm_mode.h>
#include <uapi/drm/drm_fourcc.h>
#include <drm/drm_modeset_lock.h>
@@ -739,9 +741,52 @@ struct drm_crtc {
*/
struct drm_crtc_crc crc;
#endif
+
+ /**
+ * @fence_context:
+ *
+ * timeline context used for fence operations.
+ */
+ unsigned int fence_context;
+
+ /**
+ * @fence_lock:
+ *
+ * spinlock to protect the fences in the fence_context.
+ */
+
+ spinlock_t fence_lock;
+ /**
+ * @fence_seqno:
+ *
+ * Seqno variable used as monotonic counter for the fences
+ * created on the CRTC's timeline.
+ */
+ unsigned long fence_seqno;
+
+ /**
+ * @timeline_name:
+ *
+ * The name of the CRTC's fence timeline.
+ */
+ char timeline_name[32];
};

/**
+ * dma_crtc_fence_ops - fence ops for the drm_crtc timeline
+ *
+ * It contains the dma_fence_ops that should be called by the dma_fence
+ * code. CRTC core should use this ops when initializing fences.
+ */
+extern const struct dma_fence_ops drm_crtc_fence_ops;
+
+static inline struct drm_crtc *fence_to_crtc(struct dma_fence *fence)
+{
+ BUG_ON(fence->ops != &drm_crtc_fence_ops);
+ return container_of(fence->lock, struct drm_crtc, fence_lock);
+}
+
+/**
* struct drm_mode_set - new values for a CRTC config change
* @fb: framebuffer to use for new config
* @crtc: CRTC whose configuration we're about to change
--
2.5.5

2016-11-11 10:47:58

by Brian Starkey

[permalink] [raw]
Subject: Re: [PATCH v8 1/3] drm/fence: add in-fences support

Hi Gustavo,

On Fri, Nov 11, 2016 at 02:16:07PM +0900, Gustavo Padovan wrote:
>From: Gustavo Padovan <[email protected]>
>
>There is now a new property called IN_FENCE_FD attached to every plane
>state that receives sync_file fds from userspace via the atomic commit
>IOCTL.
>
>The fd is then translated to a fence (that may be a fence_array
>subclass or just a normal fence) and then used by DRM to fence_wait() for
>all fences in the sync_file to signal. So it only commits when all
>framebuffers are ready to scanout.
>
>v2: Comments by Daniel Vetter:
> - remove set state->fence = NULL in destroy phase
> - accept fence -1 as valid and just return 0
> - do not call fence_get() - sync_file_fences_get() already calls it
> - fence_put() if state->fence is already set, in case userspace
> set the property more than once.
>
>v3: WARN_ON if fence is set but state has no FB
>
>v4: Comment from Maarten Lankhorst
> - allow set fence with no related fb
>
>v5: rename FENCE_FD to IN_FENCE_FD
>
>v6: Comments by Daniel Vetter:
> - rename plane_state->in_fence back to "fence"
> - re-introduce WARN_ON if fence set but no fb
>
> - rebase after fence -> dma_fence rename
>
>v7: Comments by Brian Starkey
> - set state->fence to NULL when duplicating the state
> - fail if IN_FENCE_FD was already set
>
>Signed-off-by: Gustavo Padovan <[email protected]>

lgtm,

Reviewed-by: Brian Starkey <[email protected]>

>---
> drivers/gpu/drm/Kconfig | 1 +
> drivers/gpu/drm/drm_atomic.c | 14 ++++++++++++++
> drivers/gpu/drm/drm_atomic_helper.c | 5 +++++
> drivers/gpu/drm/drm_crtc.c | 6 ++++++
> drivers/gpu/drm/drm_plane.c | 1 +
> include/drm/drm_crtc.h | 5 +++++
> 6 files changed, 32 insertions(+)
>
>diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
>index 25e8e37..360cb92 100644
>--- a/drivers/gpu/drm/Kconfig
>+++ b/drivers/gpu/drm/Kconfig
>@@ -12,6 +12,7 @@ menuconfig DRM
> select I2C
> select I2C_ALGOBIT
> select DMA_SHARED_BUFFER
>+ select SYNC_FILE
> help
> Kernel-level support for the Direct Rendering Infrastructure (DRI)
> introduced in XFree86 4.0. If you say Y here, you need to select
>diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
>index b096c16..8e26ad1 100644
>--- a/drivers/gpu/drm/drm_atomic.c
>+++ b/drivers/gpu/drm/drm_atomic.c
>@@ -31,6 +31,7 @@
> #include <drm/drm_mode.h>
> #include <drm/drm_plane_helper.h>
> #include <drm/drm_print.h>
>+#include <linux/sync_file.h>
>
> #include "drm_crtc_internal.h"
>
>@@ -709,6 +710,17 @@ int drm_atomic_plane_set_property(struct drm_plane *plane,
> drm_atomic_set_fb_for_plane(state, fb);
> if (fb)
> drm_framebuffer_unreference(fb);
>+ } else if (property == config->prop_in_fence_fd) {
>+ if (state->fence)
>+ return -EINVAL;
>+
>+ if (U642I64(val) == -1)
>+ return 0;
>+
>+ state->fence = sync_file_get_fence(val);
>+ if (!state->fence)
>+ return -EINVAL;
>+
> } else if (property == config->prop_crtc_id) {
> struct drm_crtc *crtc = drm_crtc_find(dev, val);
> return drm_atomic_set_crtc_for_plane(state, crtc);
>@@ -770,6 +782,8 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
>
> if (property == config->prop_fb_id) {
> *val = (state->fb) ? state->fb->base.id : 0;
>+ } else if (property == config->prop_in_fence_fd) {
>+ *val = -1;
> } else if (property == config->prop_crtc_id) {
> *val = (state->crtc) ? state->crtc->base.id : 0;
> } else if (property == config->prop_crtc_x) {
>diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
>index 75ad01d..caed870 100644
>--- a/drivers/gpu/drm/drm_atomic_helper.c
>+++ b/drivers/gpu/drm/drm_atomic_helper.c
>@@ -3076,6 +3076,8 @@ void __drm_atomic_helper_plane_duplicate_state(struct drm_plane *plane,
>
> if (state->fb)
> drm_framebuffer_reference(state->fb);
>+
>+ state->fence = NULL;
> }
> EXPORT_SYMBOL(__drm_atomic_helper_plane_duplicate_state);
>
>@@ -3114,6 +3116,9 @@ void __drm_atomic_helper_plane_destroy_state(struct drm_plane_state *state)
> {
> if (state->fb)
> drm_framebuffer_unreference(state->fb);
>+
>+ if (state->fence)
>+ dma_fence_put(state->fence);
> }
> EXPORT_SYMBOL(__drm_atomic_helper_plane_destroy_state);
>
>diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
>index ce274ed..154e040 100644
>--- a/drivers/gpu/drm/drm_crtc.c
>+++ b/drivers/gpu/drm/drm_crtc.c
>@@ -397,6 +397,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
> return -ENOMEM;
> dev->mode_config.prop_fb_id = prop;
>
>+ prop = drm_property_create_signed_range(dev, DRM_MODE_PROP_ATOMIC,
>+ "IN_FENCE_FD", -1, INT_MAX);
>+ if (!prop)
>+ return -ENOMEM;
>+ dev->mode_config.prop_in_fence_fd = prop;
>+
> prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
> "CRTC_ID", DRM_MODE_OBJECT_CRTC);
> if (!prop)
>diff --git a/drivers/gpu/drm/drm_plane.c b/drivers/gpu/drm/drm_plane.c
>index 249c0ae..3957ef8 100644
>--- a/drivers/gpu/drm/drm_plane.c
>+++ b/drivers/gpu/drm/drm_plane.c
>@@ -137,6 +137,7 @@ int drm_universal_plane_init(struct drm_device *dev, struct drm_plane *plane,
>
> if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
> drm_object_attach_property(&plane->base, config->prop_fb_id, 0);
>+ drm_object_attach_property(&plane->base, config->prop_in_fence_fd, -1);
> drm_object_attach_property(&plane->base, config->prop_crtc_id, 0);
> drm_object_attach_property(&plane->base, config->prop_crtc_x, 0);
> drm_object_attach_property(&plane->base, config->prop_crtc_y, 0);
>diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
>index 8cca2a8..11780a9 100644
>--- a/include/drm/drm_crtc.h
>+++ b/include/drm/drm_crtc.h
>@@ -1214,6 +1214,11 @@ struct drm_mode_config {
> */
> struct drm_property *prop_fb_id;
> /**
>+ * @prop_in_fence_fd: Sync File fd representing the incoming fences
>+ * for a Plane.
>+ */
>+ struct drm_property *prop_in_fence_fd;
>+ /**
> * @prop_crtc_id: Default atomic plane property to specify the
> * &drm_crtc.
> */
>--
>2.5.5
>

2016-11-11 11:41:22

by Brian Starkey

[permalink] [raw]
Subject: Re: [PATCH v8 3/3] drm/fence: add out-fences support

Hi Gustavo,

On Fri, Nov 11, 2016 at 02:16:09PM +0900, Gustavo Padovan wrote:
>From: Gustavo Padovan <[email protected]>
>
>Support DRM out-fences by creating a sync_file with a fence for each CRTC
>that sets the OUT_FENCE_PTR property.
>
>We use the out_fence pointer received in the OUT_FENCE_PTR prop to send
>the sync_file fd back to userspace.
>
>The sync_file and fd are allocated/created before commit, but the
>fd_install operation only happens after we know that commit succeed.
>
>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
>
>v3: Comments by Daniel Vetter:
> - create DRM_MODE_ATOMIC_EVENT_MASK
> - userspace should fill out_fences_ptr with the crtc_ids for which
> it wants fences back.
>
>v4: Create OUT_FENCE_PTR properties and remove old approach.
>
>v5: Comments by Brian Starkey:
> - Remove extra fence_get() in atomic_ioctl()
> - Check ret before iterating on the crtc_state
> - check ret before fd_install
> - set fence_state to NULL at the beginning
> - check fence_state->out_fence_ptr before put_user()
> - change order of fput() and put_unused_fd() on failure
>
> - Add access_ok() check to the out_fence_ptr received
> - Rebase after fence -> dma_fence rename
> - Store out_fence_ptr in the drm_atomic_state
> - Split crtc_setup_out_fence()
> - return -1 as out_fence with TEST_ONLY flag
>
>v6: Comments by Daniel Vetter
> - Add prepare/unprepare_crtc_signaling()
> - move struct drm_out_fence_state to drm_atomic.c
> - mark get_crtc_fence() as static
>
> Comments by Brian Starkey
> - proper set fence_ptr fence_state array
> - isolate fence_idx increment
>
> - improve error handling
>
>v7: Comments by Daniel Vetter
> - remove prefix from internal functions
> - make out_fence_ptr an s64 pointer
> - degrade DRM_INFO to DRM_DEBUG_ATOMIC when put_user fail
> - fix doc issues
> - filter out OUT_FENCE_PTR == NULL and do fail in this case

Do *not* fail in this case?

> - add complete_crtc_signalling()
> - krealloc fence_state on demand
>
> Comment by Brian Starkey
> - remove unused crtc_state arg from get_out_fence()
>
>Signed-off-by: Gustavo Padovan <[email protected]>

From an integration with writeback point of view, this looks fine to
me - I can add writeback to this easily.

A few comments below though:

>---
> drivers/gpu/drm/drm_atomic.c | 242 +++++++++++++++++++++++++++++++++++--------
> drivers/gpu/drm/drm_crtc.c | 8 ++
> include/drm/drm_atomic.h | 1 +
> include/drm/drm_crtc.h | 6 ++
> 4 files changed, 212 insertions(+), 45 deletions(-)
>
>diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
>index 8e26ad1..cd39f13 100644
>--- a/drivers/gpu/drm/drm_atomic.c
>+++ b/drivers/gpu/drm/drm_atomic.c
>@@ -290,6 +290,23 @@ drm_atomic_get_crtc_state(struct drm_atomic_state *state,
> }
> EXPORT_SYMBOL(drm_atomic_get_crtc_state);
>
>+static void set_out_fence_for_crtc(struct drm_atomic_state *state,
>+ struct drm_crtc *crtc, u64 __user *fence_ptr)
>+{
>+ state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = fence_ptr;
>+}
>+
>+static u64 __user * get_out_fence_for_crtc(struct drm_atomic_state *state,
>+ struct drm_crtc *crtc)
>+{
>+ u64 __user *fence_ptr;
>+
>+ fence_ptr = state->crtcs[drm_crtc_index(crtc)].out_fence_ptr;
>+ state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = NULL;
>+
>+ return fence_ptr;
>+}
>+

You missed a couple of s/u64/s64/ in the two functions above.

> /**
> * drm_atomic_set_mode_for_crtc - set mode for CRTC
> * @state: the CRTC whose incoming state to update
>@@ -491,6 +508,16 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
> &replaced);
> state->color_mgmt_changed |= replaced;
> return ret;
>+ } else if (property == config->prop_out_fence_ptr) {
>+ s64 __user *fence_ptr = u64_to_user_ptr(val);
>+
>+ if (!fence_ptr)
>+ return 0;
>+
>+ if (!access_ok(VERIFY_WRITE, fence_ptr, sizeof(*fence_ptr)))
>+ return -EFAULT;
>+
>+ set_out_fence_for_crtc(state->state, crtc, fence_ptr);
> } else if (crtc->funcs->atomic_set_property)
> return crtc->funcs->atomic_set_property(crtc, state, property, val);
> else
>@@ -533,6 +560,8 @@ drm_atomic_crtc_get_property(struct drm_crtc *crtc,
> *val = (state->ctm) ? state->ctm->base.id : 0;
> else if (property == config->gamma_lut_property)
> *val = (state->gamma_lut) ? state->gamma_lut->base.id : 0;
>+ else if (property == config->prop_out_fence_ptr)
>+ *val = 0;
> else if (crtc->funcs->atomic_get_property)
> return crtc->funcs->atomic_get_property(crtc, state, property, val);
> else
>@@ -1659,11 +1688,9 @@ int drm_atomic_debugfs_init(struct drm_minor *minor)
> */
>
> static struct drm_pending_vblank_event *create_vblank_event(
>- struct drm_device *dev, struct drm_file *file_priv,
>- struct dma_fence *fence, uint64_t user_data)
>+ struct drm_device *dev, uint64_t user_data)
> {
> struct drm_pending_vblank_event *e = NULL;
>- int ret;
>
> e = kzalloc(sizeof *e, GFP_KERNEL);
> if (!e)
>@@ -1673,17 +1700,6 @@ static struct drm_pending_vblank_event *create_vblank_event(
> e->event.base.length = sizeof(e->event);
> e->event.user_data = user_data;
>
>- if (file_priv) {
>- ret = drm_event_reserve_init(dev, file_priv, &e->base,
>- &e->event.base);
>- if (ret) {
>- kfree(e);
>- return NULL;
>- }
>- }
>-
>- e->base.fence = fence;
>-
> return e;
> }
>
>@@ -1788,6 +1804,166 @@ void drm_atomic_clean_old_fb(struct drm_device *dev,
> }
> EXPORT_SYMBOL(drm_atomic_clean_old_fb);
>
>+static struct dma_fence *get_crtc_fence(struct drm_crtc *crtc)
>+{
>+ struct dma_fence *fence;
>+
>+ fence = kzalloc(sizeof(*fence), GFP_KERNEL);
>+ if (!fence)
>+ return NULL;
>+
>+ dma_fence_init(fence, &drm_crtc_fence_ops, &crtc->fence_lock,
>+ crtc->fence_context, ++crtc->fence_seqno);
>+
>+ return fence;
>+}
>+
>+struct drm_out_fence_state {
>+ s64 __user *out_fence_ptr;
>+ struct sync_file *sync_file;
>+ int fd;
>+};
>+
>+static int setup_out_fence(struct drm_out_fence_state *fence_state,
>+ struct dma_fence *fence)
>+{
>+ fence_state->fd = get_unused_fd_flags(O_CLOEXEC);
>+ if (fence_state->fd < 0)
>+ return fence_state->fd;
>+
>+ if (put_user(fence_state->fd, fence_state->out_fence_ptr))
>+ return -EFAULT;
>+
>+ fence_state->sync_file = sync_file_create(fence);
>+ if(!fence_state->sync_file)
>+ return -ENOMEM;
>+
>+ return 0;
>+}
>+
>+static int prepare_crtc_signaling(struct drm_device *dev,
>+ struct drm_atomic_state *state,
>+ struct drm_mode_atomic *arg,
>+ struct drm_file *file_priv,
>+ struct drm_out_fence_state **fence_state,
>+ unsigned int *num_fences)
>+{
>+ struct drm_crtc *crtc;
>+ struct drm_crtc_state *crtc_state;
>+ int i, ret;
>+
>+ for_each_crtc_in_state(state, crtc, crtc_state, i) {
>+ u64 __user *fence_ptr;
>+
>+ fence_ptr = get_out_fence_for_crtc(crtc_state->state, crtc);
>+
>+ if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY && fence_ptr) {
>+ if (put_user(-1, fence_ptr))
>+ return -EFAULT;
>+
>+ continue;
>+ }
>+
>+ if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT || fence_ptr) {
>+ struct drm_pending_vblank_event *e;
>+
>+ e = create_vblank_event(dev, arg->user_data);
>+ if (!e)
>+ return -ENOMEM;
>+
>+ crtc_state->event = e;
>+ }
>+
>+ if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
>+ struct drm_pending_vblank_event *e = crtc_state->event;
>+
>+ if (!file_priv)
>+ continue;
>+
>+ ret = drm_event_reserve_init(dev, file_priv, &e->base,
>+ &e->event.base);
>+ if (ret) {
>+ kfree(e);
>+ crtc_state->event = NULL;
>+ return ret;
>+ }
>+ }
>+
>+ if (fence_ptr) {
>+ struct dma_fence *fence;
>+ struct drm_out_fence_state *f;
>+
>+ f = krealloc(*fence_state, sizeof(**fence_state) *
>+ (*num_fences + 1), GFP_KERNEL);
>+ if (!f)
>+ return -ENOMEM;
>+
>+ f[*num_fences].out_fence_ptr = fence_ptr;
>+
>+ fence = get_crtc_fence(crtc);
>+ if (!fence)
>+ return -ENOMEM;
>+
>+ ret = setup_out_fence(&f[*num_fences], fence);
>+ if (ret) {
>+ dma_fence_put(fence);
>+ return ret;
>+ }

Looks to me that the cleanup path doesn't work here. If
setup_out_fence fails, you bail out before incrementing num_fences,
and so the cleanup loop will be an iteration short.

>+
>+ (*num_fences)++;
>+
>+ *fence_state = f;

I think this is problematic too. If I understand krealloc right, when
you bail out before here and f != *fence_state, then the old
*fence_state will have been already freed, and f is going to leak.

>+ crtc_state->event->base.fence = fence;
>+ }
>+ }
>+
>+ return 0;
>+}
>+
>+static void complete_crtc_signaling(struct drm_device *dev,
>+ struct drm_atomic_state *state,
>+ struct drm_out_fence_state *fence_state,
>+ unsigned int num_fences, int ret)
>+{
>+ struct drm_crtc *crtc;
>+ struct drm_crtc_state *crtc_state;
>+ int i;
>+
>+ if (!ret) {
>+ for (i = 0; i < num_fences; i++)
>+ fd_install(fence_state[i].fd,
>+ fence_state[i].sync_file->file);
>+ return;
>+ }
>+
>+ if (!fence_state)
>+ return;
>+
>+ for_each_crtc_in_state(state, crtc, crtc_state, i) {
>+ /*
>+ * TEST_ONLY and PAGE_FLIP_EVENT are mutually
>+ * exclusive, if they weren't, this code should be
>+ * called on success for TEST_ONLY too.
>+ */
>+ if (crtc_state->event)
>+ drm_event_cancel_free(dev, &crtc_state->event->base);
>+ }

I think this event cleanup needs to be before the !fence_state check;
userspace can ask for events but no fences, and if that fails then the
events need to be freed.

Cheers,
-Brian

>+
>+ for (i = 0; i < num_fences; i++) {
>+ if (fence_state[i].sync_file)
>+ fput(fence_state[i].sync_file->file);
>+ if (fence_state[i].fd >= 0)
>+ put_unused_fd(fence_state[i].fd);
>+
>+ /* If this fails log error to the user */
>+ if (fence_state[i].out_fence_ptr &&
>+ put_user(-1, fence_state[i].out_fence_ptr))
>+ DRM_DEBUG_ATOMIC("Couldn't clear out_fence_ptr\n");
>+ }
>+
>+ kfree(fence_state);
>+}
>+
> int drm_mode_atomic_ioctl(struct drm_device *dev,
> void *data, struct drm_file *file_priv)
> {
>@@ -1800,11 +1976,10 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
> 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;
>+ unsigned int i, j, num_fences = 0;
>
> /* disallow for drivers not supporting atomic: */
> if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
>@@ -1919,20 +2094,10 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
> drm_mode_object_unreference(obj);
> }
>
>- if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
>- for_each_crtc_in_state(state, crtc, crtc_state, i) {
>- struct drm_pending_vblank_event *e;
>-
>- e = create_vblank_event(dev, file_priv, NULL,
>- arg->user_data);
>- if (!e) {
>- ret = -ENOMEM;
>- goto out;
>- }
>-
>- crtc_state->event = e;
>- }
>- }
>+ ret = prepare_crtc_signaling(dev, state, arg, file_priv, &fence_state,
>+ &num_fences);
>+ if (ret)
>+ goto out;
>
> if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) {
> /*
>@@ -1952,20 +2117,7 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
> out:
> drm_atomic_clean_old_fb(dev, plane_mask, ret);
>
>- if (ret && arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
>- /*
>- * TEST_ONLY and PAGE_FLIP_EVENT are mutually exclusive,
>- * if they weren't, this code should be called on success
>- * for TEST_ONLY too.
>- */
>-
>- for_each_crtc_in_state(state, crtc, crtc_state, i) {
>- if (!crtc_state->event)
>- continue;
>-
>- drm_event_cancel_free(dev, &crtc_state->event->base);
>- }
>- }
>+ complete_crtc_signaling(dev, state, fence_state, num_fences, ret);
>
> if (ret == -EDEADLK) {
> drm_atomic_state_clear(state);
>diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
>index 9b9881b..e8bc1ae 100644
>--- a/drivers/gpu/drm/drm_crtc.c
>+++ b/drivers/gpu/drm/drm_crtc.c
>@@ -274,6 +274,8 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
> if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
> drm_object_attach_property(&crtc->base, config->prop_active, 0);
> drm_object_attach_property(&crtc->base, config->prop_mode_id, 0);
>+ drm_object_attach_property(&crtc->base,
>+ config->prop_out_fence_ptr, 0);
> }
>
> return 0;
>@@ -434,6 +436,12 @@ static int drm_mode_create_standard_properties(struct drm_device *dev)
> return -ENOMEM;
> dev->mode_config.prop_in_fence_fd = prop;
>
>+ prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
>+ "OUT_FENCE_PTR", 0, U64_MAX);
>+ if (!prop)
>+ return -ENOMEM;
>+ dev->mode_config.prop_out_fence_ptr = prop;
>+
> prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
> "CRTC_ID", DRM_MODE_OBJECT_CRTC);
> if (!prop)
>diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
>index 331bb10..c0eaec7 100644
>--- a/include/drm/drm_atomic.h
>+++ b/include/drm/drm_atomic.h
>@@ -144,6 +144,7 @@ struct __drm_crtcs_state {
> struct drm_crtc *ptr;
> struct drm_crtc_state *state;
> struct drm_crtc_commit *commit;
>+ s64 __user *out_fence_ptr;
> };
>
> struct __drm_connnectors_state {
>diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
>index 0870de1..44571bc 100644
>--- a/include/drm/drm_crtc.h
>+++ b/include/drm/drm_crtc.h
>@@ -1264,6 +1264,12 @@ struct drm_mode_config {
> */
> struct drm_property *prop_in_fence_fd;
> /**
>+ * @prop_out_fence_ptr: Sync File fd pointer representing the
>+ * outgoing fences for a CRTC. Userspace should provide a pointer to a
>+ * value of type s64, and then cast that pointer to u64.
>+ */
>+ struct drm_property *prop_out_fence_ptr;
>+ /**
> * @prop_crtc_id: Default atomic plane property to specify the
> * &drm_crtc.
> */
>--
>2.5.5
>

2016-11-11 13:27:52

by Gustavo Padovan

[permalink] [raw]
Subject: Re: [PATCH v8 3/3] drm/fence: add out-fences support

Hi Brian,

2016-11-11 Brian Starkey <[email protected]>:

> Hi Gustavo,
>
> On Fri, Nov 11, 2016 at 02:16:09PM +0900, Gustavo Padovan wrote:
> > From: Gustavo Padovan <[email protected]>
> >
> > Support DRM out-fences by creating a sync_file with a fence for each CRTC
> > that sets the OUT_FENCE_PTR property.
> >
> > We use the out_fence pointer received in the OUT_FENCE_PTR prop to send
> > the sync_file fd back to userspace.
> >
> > The sync_file and fd are allocated/created before commit, but the
> > fd_install operation only happens after we know that commit succeed.
> >
> > 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
> >
> > v3: Comments by Daniel Vetter:
> > - create DRM_MODE_ATOMIC_EVENT_MASK
> > - userspace should fill out_fences_ptr with the crtc_ids for which
> > it wants fences back.
> >
> > v4: Create OUT_FENCE_PTR properties and remove old approach.
> >
> > v5: Comments by Brian Starkey:
> > - Remove extra fence_get() in atomic_ioctl()
> > - Check ret before iterating on the crtc_state
> > - check ret before fd_install
> > - set fence_state to NULL at the beginning
> > - check fence_state->out_fence_ptr before put_user()
> > - change order of fput() and put_unused_fd() on failure
> >
> > - Add access_ok() check to the out_fence_ptr received
> > - Rebase after fence -> dma_fence rename
> > - Store out_fence_ptr in the drm_atomic_state
> > - Split crtc_setup_out_fence()
> > - return -1 as out_fence with TEST_ONLY flag
> >
> > v6: Comments by Daniel Vetter
> > - Add prepare/unprepare_crtc_signaling()
> > - move struct drm_out_fence_state to drm_atomic.c
> > - mark get_crtc_fence() as static
> >
> > Comments by Brian Starkey
> > - proper set fence_ptr fence_state array
> > - isolate fence_idx increment
> >
> > - improve error handling
> >
> > v7: Comments by Daniel Vetter
> > - remove prefix from internal functions
> > - make out_fence_ptr an s64 pointer
> > - degrade DRM_INFO to DRM_DEBUG_ATOMIC when put_user fail
> > - fix doc issues
> > - filter out OUT_FENCE_PTR == NULL and do fail in this case
>
> Do *not* fail in this case?
>
> > - add complete_crtc_signalling()
> > - krealloc fence_state on demand
> >
> > Comment by Brian Starkey
> > - remove unused crtc_state arg from get_out_fence()
> >
> > Signed-off-by: Gustavo Padovan <[email protected]>
>
> From an integration with writeback point of view, this looks fine to
> me - I can add writeback to this easily.
>
> A few comments below though:
>
> > ---
> > drivers/gpu/drm/drm_atomic.c | 242 +++++++++++++++++++++++++++++++++++--------
> > drivers/gpu/drm/drm_crtc.c | 8 ++
> > include/drm/drm_atomic.h | 1 +
> > include/drm/drm_crtc.h | 6 ++
> > 4 files changed, 212 insertions(+), 45 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> > index 8e26ad1..cd39f13 100644
> > --- a/drivers/gpu/drm/drm_atomic.c
> > +++ b/drivers/gpu/drm/drm_atomic.c
> > @@ -290,6 +290,23 @@ drm_atomic_get_crtc_state(struct drm_atomic_state *state,
> > }
> > EXPORT_SYMBOL(drm_atomic_get_crtc_state);
> >
> > +static void set_out_fence_for_crtc(struct drm_atomic_state *state,
> > + struct drm_crtc *crtc, u64 __user *fence_ptr)
> > +{
> > + state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = fence_ptr;
> > +}
> > +
> > +static u64 __user * get_out_fence_for_crtc(struct drm_atomic_state *state,
> > + struct drm_crtc *crtc)
> > +{
> > + u64 __user *fence_ptr;
> > +
> > + fence_ptr = state->crtcs[drm_crtc_index(crtc)].out_fence_ptr;
> > + state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = NULL;
> > +
> > + return fence_ptr;
> > +}
> > +
>
> You missed a couple of s/u64/s64/ in the two functions above.
>
> > /**
> > * drm_atomic_set_mode_for_crtc - set mode for CRTC
> > * @state: the CRTC whose incoming state to update
> > @@ -491,6 +508,16 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
> > &replaced);
> > state->color_mgmt_changed |= replaced;
> > return ret;
> > + } else if (property == config->prop_out_fence_ptr) {
> > + s64 __user *fence_ptr = u64_to_user_ptr(val);
> > +
> > + if (!fence_ptr)
> > + return 0;
> > +
> > + if (!access_ok(VERIFY_WRITE, fence_ptr, sizeof(*fence_ptr)))
> > + return -EFAULT;
> > +
> > + set_out_fence_for_crtc(state->state, crtc, fence_ptr);
> > } else if (crtc->funcs->atomic_set_property)
> > return crtc->funcs->atomic_set_property(crtc, state, property, val);
> > else
> > @@ -533,6 +560,8 @@ drm_atomic_crtc_get_property(struct drm_crtc *crtc,
> > *val = (state->ctm) ? state->ctm->base.id : 0;
> > else if (property == config->gamma_lut_property)
> > *val = (state->gamma_lut) ? state->gamma_lut->base.id : 0;
> > + else if (property == config->prop_out_fence_ptr)
> > + *val = 0;
> > else if (crtc->funcs->atomic_get_property)
> > return crtc->funcs->atomic_get_property(crtc, state, property, val);
> > else
> > @@ -1659,11 +1688,9 @@ int drm_atomic_debugfs_init(struct drm_minor *minor)
> > */
> >
> > static struct drm_pending_vblank_event *create_vblank_event(
> > - struct drm_device *dev, struct drm_file *file_priv,
> > - struct dma_fence *fence, uint64_t user_data)
> > + struct drm_device *dev, uint64_t user_data)
> > {
> > struct drm_pending_vblank_event *e = NULL;
> > - int ret;
> >
> > e = kzalloc(sizeof *e, GFP_KERNEL);
> > if (!e)
> > @@ -1673,17 +1700,6 @@ static struct drm_pending_vblank_event *create_vblank_event(
> > e->event.base.length = sizeof(e->event);
> > e->event.user_data = user_data;
> >
> > - if (file_priv) {
> > - ret = drm_event_reserve_init(dev, file_priv, &e->base,
> > - &e->event.base);
> > - if (ret) {
> > - kfree(e);
> > - return NULL;
> > - }
> > - }
> > -
> > - e->base.fence = fence;
> > -
> > return e;
> > }
> >
> > @@ -1788,6 +1804,166 @@ void drm_atomic_clean_old_fb(struct drm_device *dev,
> > }
> > EXPORT_SYMBOL(drm_atomic_clean_old_fb);
> >
> > +static struct dma_fence *get_crtc_fence(struct drm_crtc *crtc)
> > +{
> > + struct dma_fence *fence;
> > +
> > + fence = kzalloc(sizeof(*fence), GFP_KERNEL);
> > + if (!fence)
> > + return NULL;
> > +
> > + dma_fence_init(fence, &drm_crtc_fence_ops, &crtc->fence_lock,
> > + crtc->fence_context, ++crtc->fence_seqno);
> > +
> > + return fence;
> > +}
> > +
> > +struct drm_out_fence_state {
> > + s64 __user *out_fence_ptr;
> > + struct sync_file *sync_file;
> > + int fd;
> > +};
> > +
> > +static int setup_out_fence(struct drm_out_fence_state *fence_state,
> > + struct dma_fence *fence)
> > +{
> > + fence_state->fd = get_unused_fd_flags(O_CLOEXEC);
> > + if (fence_state->fd < 0)
> > + return fence_state->fd;
> > +
> > + if (put_user(fence_state->fd, fence_state->out_fence_ptr))
> > + return -EFAULT;
> > +
> > + fence_state->sync_file = sync_file_create(fence);
> > + if(!fence_state->sync_file)
> > + return -ENOMEM;
> > +
> > + return 0;
> > +}
> > +
> > +static int prepare_crtc_signaling(struct drm_device *dev,
> > + struct drm_atomic_state *state,
> > + struct drm_mode_atomic *arg,
> > + struct drm_file *file_priv,
> > + struct drm_out_fence_state **fence_state,
> > + unsigned int *num_fences)
> > +{
> > + struct drm_crtc *crtc;
> > + struct drm_crtc_state *crtc_state;
> > + int i, ret;
> > +
> > + for_each_crtc_in_state(state, crtc, crtc_state, i) {
> > + u64 __user *fence_ptr;
> > +
> > + fence_ptr = get_out_fence_for_crtc(crtc_state->state, crtc);
> > +
> > + if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY && fence_ptr) {
> > + if (put_user(-1, fence_ptr))
> > + return -EFAULT;
> > +
> > + continue;
> > + }
> > +
> > + if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT || fence_ptr) {
> > + struct drm_pending_vblank_event *e;
> > +
> > + e = create_vblank_event(dev, arg->user_data);
> > + if (!e)
> > + return -ENOMEM;
> > +
> > + crtc_state->event = e;
> > + }
> > +
> > + if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
> > + struct drm_pending_vblank_event *e = crtc_state->event;
> > +
> > + if (!file_priv)
> > + continue;
> > +
> > + ret = drm_event_reserve_init(dev, file_priv, &e->base,
> > + &e->event.base);
> > + if (ret) {
> > + kfree(e);
> > + crtc_state->event = NULL;
> > + return ret;
> > + }
> > + }
> > +
> > + if (fence_ptr) {
> > + struct dma_fence *fence;
> > + struct drm_out_fence_state *f;
> > +
> > + f = krealloc(*fence_state, sizeof(**fence_state) *
> > + (*num_fences + 1), GFP_KERNEL);
> > + if (!f)
> > + return -ENOMEM;
> > +
> > + f[*num_fences].out_fence_ptr = fence_ptr;
> > +
> > + fence = get_crtc_fence(crtc);
> > + if (!fence)
> > + return -ENOMEM;
> > +
> > + ret = setup_out_fence(&f[*num_fences], fence);
> > + if (ret) {
> > + dma_fence_put(fence);
> > + return ret;
> > + }
>
> Looks to me that the cleanup path doesn't work here. If
> setup_out_fence fails, you bail out before incrementing num_fences,
> and so the cleanup loop will be an iteration short.
>
> > +
> > + (*num_fences)++;
> > +
> > + *fence_state = f;
>
> I think this is problematic too. If I understand krealloc right, when
> you bail out before here and f != *fence_state, then the old
> *fence_state will have been already freed, and f is going to leak.

Yes, it is broken, I missed that. I think for fence_state I can just
move the assignment a few lines above and for num_fences one way is to
increment it before returning on error.

>
> > + crtc_state->event->base.fence = fence;
> > + }
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static void complete_crtc_signaling(struct drm_device *dev,
> > + struct drm_atomic_state *state,
> > + struct drm_out_fence_state *fence_state,
> > + unsigned int num_fences, int ret)
> > +{
> > + struct drm_crtc *crtc;
> > + struct drm_crtc_state *crtc_state;
> > + int i;
> > +
> > + if (!ret) {
> > + for (i = 0; i < num_fences; i++)
> > + fd_install(fence_state[i].fd,
> > + fence_state[i].sync_file->file);
> > + return;
> > + }
> > +
> > + if (!fence_state)
> > + return;
> > +
> > + for_each_crtc_in_state(state, crtc, crtc_state, i) {
> > + /*
> > + * TEST_ONLY and PAGE_FLIP_EVENT are mutually
> > + * exclusive, if they weren't, this code should be
> > + * called on success for TEST_ONLY too.
> > + */
> > + if (crtc_state->event)
> > + drm_event_cancel_free(dev, &crtc_state->event->base);
> > + }
>
> I think this event cleanup needs to be before the !fence_state check;
> userspace can ask for events but no fences, and if that fails then the
> events need to be freed.

Yes. In the previous version this was the correct flow, but with v8 the
clean up actually needs to happen before.

Gustavo

2016-11-11 14:18:05

by Gustavo Padovan

[permalink] [raw]
Subject: Re: [PATCH v8 0/3] drm: add explict fencing

Subject was supposed to be v9! sorry about that.

2016-11-11 Gustavo Padovan <[email protected]>:

> From: Gustavo Padovan <[email protected]>
>
> Hi,
>
> Another iteration after Brian comments. Please refer to the cover letter[1] in
> a previous version to check for more details.
>
> The changes since the last version can be seen in commit message on each patch.
>
> Robert Foss managed to port Android's drm_hwcomposer to the new HWC2 API and
> added support to fences. Current patches can be seen here:
>
> https://git.collabora.com/cgit/user/robertfoss/drm_hwcomposer.git/log/?h=hwc2_fence_v1
>
> He ran AOSP on top of padovan/fences kernel branch with full fence support on
> qemu/virgl and msm db410c. That means we already have a working open source
> userspace using the explicit fencing implementation.
>
> Also i-g-t testing are available with all tests suggested in v7 included:
>
> https://git.collabora.com/cgit/user/padovan/intel-gpu-tools.git/log/
>
> Please review!
>
> Gustavo
>
> [1] https://www.mail-archive.com/[email protected]/msg1253822.html
>
> ---
> Gustavo Padovan (3):
> drm/fence: add in-fences support
> drm/fence: add fence timeline to drm_crtc
> drm/fence: add out-fences support
>
> drivers/gpu/drm/Kconfig | 1 +
> drivers/gpu/drm/drm_atomic.c | 257 +++++++++++++++++++++++++++++-------
> drivers/gpu/drm/drm_atomic_helper.c | 5 +
> drivers/gpu/drm/drm_crtc.c | 45 +++++++
> drivers/gpu/drm/drm_plane.c | 1 +
> include/drm/drm_atomic.h | 1 +
> include/drm/drm_crtc.h | 56 ++++++++
> 7 files changed, 321 insertions(+), 45 deletions(-)
>
> --
> 2.5.5
>

2016-11-11 15:54:48

by Sean Paul

[permalink] [raw]
Subject: Re: [PATCH v8 2/3] drm/fence: add fence timeline to drm_crtc

On Fri, Nov 11, 2016 at 12:16 AM, Gustavo Padovan <[email protected]> wrote:
> From: Gustavo Padovan <[email protected]>
>
> Create one timeline context for each CRTC to be able to handle out-fences
> and signal them. It adds a few members to struct drm_crtc: fence_context,
> where we store the context we get from fence_context_alloc(), the
> fence seqno and the fence lock, that we pass in fence_init() to be
> used by the fence.
>
> v2: Comment by Daniel Stone:
> - add BUG_ON() to fence_to_crtc() macro
>
> v3: Comment by Ville Syrjälä
> - Use more meaningful name as crtc timeline name
>
> v4: Comments by Brian Starkey
> - Use even more meaninful name for the crtc timeline
> - add doc for timeline_name
> Comment by Daniel Vetter
> - use in-line style for comments
>
> - rebase after fence -> dma_fence rename
>
> v5: Comment by Daniel Vetter
> - Add doc for drm_crtc_fence_ops
>
> Signed-off-by: Gustavo Padovan <[email protected]>
> Reviewed-by: Daniel Vetter <[email protected]>

Reviewed-by: Sean Paul <[email protected]>

> ---
> drivers/gpu/drm/drm_crtc.c | 31 +++++++++++++++++++++++++++++++
> include/drm/drm_crtc.h | 45 +++++++++++++++++++++++++++++++++++++++++++++
> 2 files changed, 76 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index 154e040..9b9881b 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -165,6 +165,32 @@ static void drm_crtc_crc_fini(struct drm_crtc *crtc)
> #endif
> }
>
> +static const char *drm_crtc_fence_get_driver_name(struct dma_fence *fence)
> +{
> + struct drm_crtc *crtc = fence_to_crtc(fence);
> +
> + return crtc->dev->driver->name;
> +}
> +
> +static const char *drm_crtc_fence_get_timeline_name(struct dma_fence *fence)
> +{
> + struct drm_crtc *crtc = fence_to_crtc(fence);
> +
> + return crtc->timeline_name;
> +}
> +
> +static bool drm_crtc_fence_enable_signaling(struct dma_fence *fence)
> +{
> + return true;
> +}
> +
> +const struct dma_fence_ops drm_crtc_fence_ops = {
> + .get_driver_name = drm_crtc_fence_get_driver_name,
> + .get_timeline_name = drm_crtc_fence_get_timeline_name,
> + .enable_signaling = drm_crtc_fence_enable_signaling,
> + .wait = dma_fence_default_wait,
> +};
> +
> /**
> * drm_crtc_init_with_planes - Initialise a new CRTC object with
> * specified primary and cursor planes.
> @@ -222,6 +248,11 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
> return -ENOMEM;
> }
>
> + crtc->fence_context = dma_fence_context_alloc(1);
> + spin_lock_init(&crtc->fence_lock);
> + snprintf(crtc->timeline_name, sizeof(crtc->timeline_name),
> + "CRTC:%d-%s", crtc->base.id, crtc->name);
> +
> crtc->base.properties = &crtc->properties;
>
> list_add_tail(&crtc->head, &config->crtc_list);
> diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
> index 11780a9..0870de1 100644
> --- a/include/drm/drm_crtc.h
> +++ b/include/drm/drm_crtc.h
> @@ -32,6 +32,8 @@
> #include <linux/fb.h>
> #include <linux/hdmi.h>
> #include <linux/media-bus-format.h>
> +#include <linux/srcu.h>
> +#include <linux/dma-fence.h>
> #include <uapi/drm/drm_mode.h>
> #include <uapi/drm/drm_fourcc.h>
> #include <drm/drm_modeset_lock.h>
> @@ -739,9 +741,52 @@ struct drm_crtc {
> */
> struct drm_crtc_crc crc;
> #endif
> +
> + /**
> + * @fence_context:
> + *
> + * timeline context used for fence operations.
> + */
> + unsigned int fence_context;
> +
> + /**
> + * @fence_lock:
> + *
> + * spinlock to protect the fences in the fence_context.
> + */
> +
> + spinlock_t fence_lock;
> + /**
> + * @fence_seqno:
> + *
> + * Seqno variable used as monotonic counter for the fences
> + * created on the CRTC's timeline.
> + */
> + unsigned long fence_seqno;
> +
> + /**
> + * @timeline_name:
> + *
> + * The name of the CRTC's fence timeline.
> + */
> + char timeline_name[32];
> };
>
> /**
> + * dma_crtc_fence_ops - fence ops for the drm_crtc timeline
> + *
> + * It contains the dma_fence_ops that should be called by the dma_fence
> + * code. CRTC core should use this ops when initializing fences.
> + */
> +extern const struct dma_fence_ops drm_crtc_fence_ops;
> +
> +static inline struct drm_crtc *fence_to_crtc(struct dma_fence *fence)
> +{
> + BUG_ON(fence->ops != &drm_crtc_fence_ops);
> + return container_of(fence->lock, struct drm_crtc, fence_lock);
> +}
> +
> +/**
> * struct drm_mode_set - new values for a CRTC config change
> * @fb: framebuffer to use for new config
> * @crtc: CRTC whose configuration we're about to change
> --
> 2.5.5
>