[PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Chia-I Wu]

In practice, trace_dma_fence_init is good enough and almost no driver
calls trace_dma_fence_emit.  But this is still more correct in theory.

Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
Cc: Rob Clark <robdclark@chromium.org>
---
 drivers/gpu/drm/msm/msm_gpu.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index faf0c242874e..a82193f41ea2 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -15,6 +15,7 @@
 #include <linux/string_helpers.h>
 #include <linux/devcoredump.h>
 #include <linux/sched/task.h>
+#include <trace/events/dma_fence.h>
 
 /*
  * Power Management:
@@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 	gpu->active_submits++;
 	mutex_unlock(&gpu->active_lock);
 
+	trace_dma_fence_emit(submit->hw_fence);
 	gpu->funcs->submit(gpu, submit);
 	gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
 
-- 
2.35.1.1178.g4f1659d476-goog

[PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Chia-I Wu]

In practice, trace_dma_fence_init is good enough and almost no driver
calls trace_dma_fence_emit.  But this is still more correct in theory.

Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
Cc: Rob Clark <robdclark@chromium.org>
---
 drivers/gpu/drm/msm/msm_gpu.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index faf0c242874e..a82193f41ea2 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -15,6 +15,7 @@
 #include <linux/string_helpers.h>
 #include <linux/devcoredump.h>
 #include <linux/sched/task.h>
+#include <trace/events/dma_fence.h>
 
 /*
  * Power Management:
@@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 	gpu->active_submits++;
 	mutex_unlock(&gpu->active_lock);
 
+	trace_dma_fence_emit(submit->hw_fence);
 	gpu->funcs->submit(gpu, submit);
 	gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
 
-- 
2.35.1.1178.g4f1659d476-goog

Re: [PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Dmitry Baryshkov]

On Sat, 9 Apr 2022 at 00:12, Chia-I Wu <olvaffe@gmail.com> wrote:
>
> In practice, trace_dma_fence_init is good enough and almost no driver
> calls trace_dma_fence_emit.  But this is still more correct in theory.

Please mention in the commit message that the trace_dma_fence_init()
is called from dma_fence_init().
With that in place:

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

>
> Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
> Cc: Rob Clark <robdclark@chromium.org>
> ---
>  drivers/gpu/drm/msm/msm_gpu.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> index faf0c242874e..a82193f41ea2 100644
> --- a/drivers/gpu/drm/msm/msm_gpu.c
> +++ b/drivers/gpu/drm/msm/msm_gpu.c
> @@ -15,6 +15,7 @@
>  #include <linux/string_helpers.h>
>  #include <linux/devcoredump.h>
>  #include <linux/sched/task.h>
> +#include <trace/events/dma_fence.h>
>
>  /*
>   * Power Management:
> @@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
>         gpu->active_submits++;
>         mutex_unlock(&gpu->active_lock);
>
> +       trace_dma_fence_emit(submit->hw_fence);
>         gpu->funcs->submit(gpu, submit);
>         gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
>
> --
> 2.35.1.1178.g4f1659d476-goog
>


-- 
With best wishes
Dmitry

Re: [PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Dmitry Baryshkov]

On Sat, 9 Apr 2022 at 00:12, Chia-I Wu <olvaffe@gmail.com> wrote:
>
> In practice, trace_dma_fence_init is good enough and almost no driver
> calls trace_dma_fence_emit.  But this is still more correct in theory.

Please mention in the commit message that the trace_dma_fence_init()
is called from dma_fence_init().
With that in place:

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

>
> Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
> Cc: Rob Clark <robdclark@chromium.org>
> ---
>  drivers/gpu/drm/msm/msm_gpu.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> index faf0c242874e..a82193f41ea2 100644
> --- a/drivers/gpu/drm/msm/msm_gpu.c
> +++ b/drivers/gpu/drm/msm/msm_gpu.c
> @@ -15,6 +15,7 @@
>  #include <linux/string_helpers.h>
>  #include <linux/devcoredump.h>
>  #include <linux/sched/task.h>
> +#include <trace/events/dma_fence.h>
>
>  /*
>   * Power Management:
> @@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
>         gpu->active_submits++;
>         mutex_unlock(&gpu->active_lock);
>
> +       trace_dma_fence_emit(submit->hw_fence);
>         gpu->funcs->submit(gpu, submit);
>         gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
>
> --
> 2.35.1.1178.g4f1659d476-goog
>


-- 
With best wishes
Dmitry

Re: [PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Christian König]

Am 08.04.22 um 23:12 schrieb Chia-I Wu:
> In practice, trace_dma_fence_init is good enough and almost no driver
> calls trace_dma_fence_emit.  But this is still more correct in theory.

Well, the reason why basically no driver is calling this is because it 
is pretty much deprecated.

We do have a case in the GPU scheduler where it makes sense to distinct 
between init and emit, but it doesn't really matter for drivers.

So I'm not sure if it's a good idea to add that here.

Regards,
Christian.

>
> Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
> Cc: Rob Clark <robdclark@chromium.org>
> ---
>   drivers/gpu/drm/msm/msm_gpu.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> index faf0c242874e..a82193f41ea2 100644
> --- a/drivers/gpu/drm/msm/msm_gpu.c
> +++ b/drivers/gpu/drm/msm/msm_gpu.c
> @@ -15,6 +15,7 @@
>   #include <linux/string_helpers.h>
>   #include <linux/devcoredump.h>
>   #include <linux/sched/task.h>
> +#include <trace/events/dma_fence.h>
>   
>   /*
>    * Power Management:
> @@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
>   	gpu->active_submits++;
>   	mutex_unlock(&gpu->active_lock);
>   
> +	trace_dma_fence_emit(submit->hw_fence);
>   	gpu->funcs->submit(gpu, submit);
>   	gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
>   

Re: [PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Christian König]

Am 08.04.22 um 23:12 schrieb Chia-I Wu:
> In practice, trace_dma_fence_init is good enough and almost no driver
> calls trace_dma_fence_emit.  But this is still more correct in theory.

Well, the reason why basically no driver is calling this is because it 
is pretty much deprecated.

We do have a case in the GPU scheduler where it makes sense to distinct 
between init and emit, but it doesn't really matter for drivers.

So I'm not sure if it's a good idea to add that here.

Regards,
Christian.

>
> Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
> Cc: Rob Clark <robdclark@chromium.org>
> ---
>   drivers/gpu/drm/msm/msm_gpu.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> index faf0c242874e..a82193f41ea2 100644
> --- a/drivers/gpu/drm/msm/msm_gpu.c
> +++ b/drivers/gpu/drm/msm/msm_gpu.c
> @@ -15,6 +15,7 @@
>   #include <linux/string_helpers.h>
>   #include <linux/devcoredump.h>
>   #include <linux/sched/task.h>
> +#include <trace/events/dma_fence.h>
>   
>   /*
>    * Power Management:
> @@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
>   	gpu->active_submits++;
>   	mutex_unlock(&gpu->active_lock);
>   
> +	trace_dma_fence_emit(submit->hw_fence);
>   	gpu->funcs->submit(gpu, submit);
>   	gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
>   

Re: [PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Chia-I Wu]

On Sat, Apr 9, 2022 at 7:33 AM Christian König <christian.koenig@amd.com> wrote:
>
> Am 08.04.22 um 23:12 schrieb Chia-I Wu:
> > In practice, trace_dma_fence_init is good enough and almost no driver
> > calls trace_dma_fence_emit.  But this is still more correct in theory.
>
> Well, the reason why basically no driver is calling this is because it
> is pretty much deprecated.
Why is it considered deprecated?  trace_dma_fence_{emit,signaled} are
useful to visualize fence timelines.  I am actually less sure about
how trace_dma_fence_{init,destroy} are used.

Is it because trace_dma_fence_init is called automatically, and is
good enough most of the time?

>
> We do have a case in the GPU scheduler where it makes sense to distinct
> between init and emit, but it doesn't really matter for drivers.
virtio also has a case where init and emit can be far apart, when the
host cannot process commands fast enough and there is no space in
virtqueue.

>
> So I'm not sure if it's a good idea to add that here.
>
> Regards,
> Christian.
>
> >
> > Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
> > Cc: Rob Clark <robdclark@chromium.org>
> > ---
> >   drivers/gpu/drm/msm/msm_gpu.c | 2 ++
> >   1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> > index faf0c242874e..a82193f41ea2 100644
> > --- a/drivers/gpu/drm/msm/msm_gpu.c
> > +++ b/drivers/gpu/drm/msm/msm_gpu.c
> > @@ -15,6 +15,7 @@
> >   #include <linux/string_helpers.h>
> >   #include <linux/devcoredump.h>
> >   #include <linux/sched/task.h>
> > +#include <trace/events/dma_fence.h>
> >
> >   /*
> >    * Power Management:
> > @@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
> >       gpu->active_submits++;
> >       mutex_unlock(&gpu->active_lock);
> >
> > +     trace_dma_fence_emit(submit->hw_fence);
> >       gpu->funcs->submit(gpu, submit);
> >       gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
> >
>

Re: [PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Chia-I Wu]

On Sat, Apr 9, 2022 at 7:33 AM Christian König <christian.koenig@amd.com> wrote:
>
> Am 08.04.22 um 23:12 schrieb Chia-I Wu:
> > In practice, trace_dma_fence_init is good enough and almost no driver
> > calls trace_dma_fence_emit.  But this is still more correct in theory.
>
> Well, the reason why basically no driver is calling this is because it
> is pretty much deprecated.
Why is it considered deprecated?  trace_dma_fence_{emit,signaled} are
useful to visualize fence timelines.  I am actually less sure about
how trace_dma_fence_{init,destroy} are used.

Is it because trace_dma_fence_init is called automatically, and is
good enough most of the time?

>
> We do have a case in the GPU scheduler where it makes sense to distinct
> between init and emit, but it doesn't really matter for drivers.
virtio also has a case where init and emit can be far apart, when the
host cannot process commands fast enough and there is no space in
virtqueue.

>
> So I'm not sure if it's a good idea to add that here.
>
> Regards,
> Christian.
>
> >
> > Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
> > Cc: Rob Clark <robdclark@chromium.org>
> > ---
> >   drivers/gpu/drm/msm/msm_gpu.c | 2 ++
> >   1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> > index faf0c242874e..a82193f41ea2 100644
> > --- a/drivers/gpu/drm/msm/msm_gpu.c
> > +++ b/drivers/gpu/drm/msm/msm_gpu.c
> > @@ -15,6 +15,7 @@
> >   #include <linux/string_helpers.h>
> >   #include <linux/devcoredump.h>
> >   #include <linux/sched/task.h>
> > +#include <trace/events/dma_fence.h>
> >
> >   /*
> >    * Power Management:
> > @@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
> >       gpu->active_submits++;
> >       mutex_unlock(&gpu->active_lock);
> >
> > +     trace_dma_fence_emit(submit->hw_fence);
> >       gpu->funcs->submit(gpu, submit);
> >       gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
> >
>

Re: [PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Rob Clark]

On Sat, Apr 9, 2022 at 7:33 AM Christian König <christian.koenig@amd.com> wrote:
>
> Am 08.04.22 um 23:12 schrieb Chia-I Wu:
> > In practice, trace_dma_fence_init is good enough and almost no driver
> > calls trace_dma_fence_emit.  But this is still more correct in theory.
>
> Well, the reason why basically no driver is calling this is because it
> is pretty much deprecated.
>
> We do have a case in the GPU scheduler where it makes sense to distinct
> between init and emit, but it doesn't really matter for drivers.
>
> So I'm not sure if it's a good idea to add that here.

visualization can't easily differentiate between drivers/timelines
where the split matters and ones where it doesn't..  IMO it is better
to just have the extra trace even in the cases where it comes at the
same time as the init trace

BR,
-R

> Regards,
> Christian.
>
> >
> > Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
> > Cc: Rob Clark <robdclark@chromium.org>
> > ---
> >   drivers/gpu/drm/msm/msm_gpu.c | 2 ++
> >   1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> > index faf0c242874e..a82193f41ea2 100644
> > --- a/drivers/gpu/drm/msm/msm_gpu.c
> > +++ b/drivers/gpu/drm/msm/msm_gpu.c
> > @@ -15,6 +15,7 @@
> >   #include <linux/string_helpers.h>
> >   #include <linux/devcoredump.h>
> >   #include <linux/sched/task.h>
> > +#include <trace/events/dma_fence.h>
> >
> >   /*
> >    * Power Management:
> > @@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
> >       gpu->active_submits++;
> >       mutex_unlock(&gpu->active_lock);
> >
> > +     trace_dma_fence_emit(submit->hw_fence);
> >       gpu->funcs->submit(gpu, submit);
> >       gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
> >
>

Re: [PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Rob Clark]

On Sat, Apr 9, 2022 at 7:33 AM Christian König <christian.koenig@amd.com> wrote:
>
> Am 08.04.22 um 23:12 schrieb Chia-I Wu:
> > In practice, trace_dma_fence_init is good enough and almost no driver
> > calls trace_dma_fence_emit.  But this is still more correct in theory.
>
> Well, the reason why basically no driver is calling this is because it
> is pretty much deprecated.
>
> We do have a case in the GPU scheduler where it makes sense to distinct
> between init and emit, but it doesn't really matter for drivers.
>
> So I'm not sure if it's a good idea to add that here.

visualization can't easily differentiate between drivers/timelines
where the split matters and ones where it doesn't..  IMO it is better
to just have the extra trace even in the cases where it comes at the
same time as the init trace

BR,
-R

> Regards,
> Christian.
>
> >
> > Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
> > Cc: Rob Clark <robdclark@chromium.org>
> > ---
> >   drivers/gpu/drm/msm/msm_gpu.c | 2 ++
> >   1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> > index faf0c242874e..a82193f41ea2 100644
> > --- a/drivers/gpu/drm/msm/msm_gpu.c
> > +++ b/drivers/gpu/drm/msm/msm_gpu.c
> > @@ -15,6 +15,7 @@
> >   #include <linux/string_helpers.h>
> >   #include <linux/devcoredump.h>
> >   #include <linux/sched/task.h>
> > +#include <trace/events/dma_fence.h>
> >
> >   /*
> >    * Power Management:
> > @@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
> >       gpu->active_submits++;
> >       mutex_unlock(&gpu->active_lock);
> >
> > +     trace_dma_fence_emit(submit->hw_fence);
> >       gpu->funcs->submit(gpu, submit);
> >       gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
> >
>

Re: [PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Christian König]

Sorry for the delayed reply.

Am 12.04.22 um 21:41 schrieb Rob Clark:
> On Sat, Apr 9, 2022 at 7:33 AM Christian König <christian.koenig@amd.com> wrote:
>> Am 08.04.22 um 23:12 schrieb Chia-I Wu:
>>> In practice, trace_dma_fence_init is good enough and almost no driver
>>> calls trace_dma_fence_emit.  But this is still more correct in theory.
>> Well, the reason why basically no driver is calling this is because it
>> is pretty much deprecated.
>>
>> We do have a case in the GPU scheduler where it makes sense to distinct
>> between init and emit, but it doesn't really matter for drivers.
>>
>> So I'm not sure if it's a good idea to add that here.
> visualization can't easily differentiate between drivers/timelines
> where the split matters and ones where it doesn't..  IMO it is better
> to just have the extra trace even in the cases where it comes at the
> same time as the init trace

That's exactly the reason why I want to remove the extra trace.

To make it clear this is only useful for debugging and *NOT* for 
actually visualizing things.

So by adding that here you add more confusion than solving anything.

Regards,
Christian.

>
> BR,
> -R
>
>> Regards,
>> Christian.
>>
>>> Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
>>> Cc: Rob Clark <robdclark@chromium.org>
>>> ---
>>>    drivers/gpu/drm/msm/msm_gpu.c | 2 ++
>>>    1 file changed, 2 insertions(+)
>>>
>>> diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
>>> index faf0c242874e..a82193f41ea2 100644
>>> --- a/drivers/gpu/drm/msm/msm_gpu.c
>>> +++ b/drivers/gpu/drm/msm/msm_gpu.c
>>> @@ -15,6 +15,7 @@
>>>    #include <linux/string_helpers.h>
>>>    #include <linux/devcoredump.h>
>>>    #include <linux/sched/task.h>
>>> +#include <trace/events/dma_fence.h>
>>>
>>>    /*
>>>     * Power Management:
>>> @@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
>>>        gpu->active_submits++;
>>>        mutex_unlock(&gpu->active_lock);
>>>
>>> +     trace_dma_fence_emit(submit->hw_fence);
>>>        gpu->funcs->submit(gpu, submit);
>>>        gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
>>>

Re: [PATCH] drm/msm: add trace_dma_fence_emit to msm_gpu_submit

[Christian König]

Sorry for the delayed reply.

Am 12.04.22 um 21:41 schrieb Rob Clark:
> On Sat, Apr 9, 2022 at 7:33 AM Christian König <christian.koenig@amd.com> wrote:
>> Am 08.04.22 um 23:12 schrieb Chia-I Wu:
>>> In practice, trace_dma_fence_init is good enough and almost no driver
>>> calls trace_dma_fence_emit.  But this is still more correct in theory.
>> Well, the reason why basically no driver is calling this is because it
>> is pretty much deprecated.
>>
>> We do have a case in the GPU scheduler where it makes sense to distinct
>> between init and emit, but it doesn't really matter for drivers.
>>
>> So I'm not sure if it's a good idea to add that here.
> visualization can't easily differentiate between drivers/timelines
> where the split matters and ones where it doesn't..  IMO it is better
> to just have the extra trace even in the cases where it comes at the
> same time as the init trace

That's exactly the reason why I want to remove the extra trace.

To make it clear this is only useful for debugging and *NOT* for 
actually visualizing things.

So by adding that here you add more confusion than solving anything.

Regards,
Christian.

>
> BR,
> -R
>
>> Regards,
>> Christian.
>>
>>> Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
>>> Cc: Rob Clark <robdclark@chromium.org>
>>> ---
>>>    drivers/gpu/drm/msm/msm_gpu.c | 2 ++
>>>    1 file changed, 2 insertions(+)
>>>
>>> diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
>>> index faf0c242874e..a82193f41ea2 100644
>>> --- a/drivers/gpu/drm/msm/msm_gpu.c
>>> +++ b/drivers/gpu/drm/msm/msm_gpu.c
>>> @@ -15,6 +15,7 @@
>>>    #include <linux/string_helpers.h>
>>>    #include <linux/devcoredump.h>
>>>    #include <linux/sched/task.h>
>>> +#include <trace/events/dma_fence.h>
>>>
>>>    /*
>>>     * Power Management:
>>> @@ -769,6 +770,7 @@ void msm_gpu_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
>>>        gpu->active_submits++;
>>>        mutex_unlock(&gpu->active_lock);
>>>
>>> +     trace_dma_fence_emit(submit->hw_fence);
>>>        gpu->funcs->submit(gpu, submit);
>>>        gpu->cur_ctx_seqno = submit->queue->ctx->seqno;
>>>