[PATCH 03/21] drm/amdgpu:fix scheduler hw reset&recovery

[deathsimple@xxxxxxxxxxx (Christian König)]

Am 06.02.2017 um 04:18 schrieb Zhou, David(ChunMing):
> I'm curious what problem this patch fix? Any crash?
>
> My impression list_for will check if the list is empty, am I wrong?

Yeah, I agree as well. list_for won't do anything if the list is empty.

So this patch doesn't has any effect as far as I can see.

Regards,
Christian.

>
> Regards,
> David Zhou
>
> -----Original Message-----
> From: amd-gfx [mailto:amd-gfx-bounces at lists.freedesktop.org] On Behalf Of Monk Liu
> Sent: Saturday, February 04, 2017 6:22 PM
> To: amd-gfx at lists.freedesktop.org
> Cc: Liu, Monk <Monk.Liu at amd.com>
> Subject: [PATCH 03/21] drm/amdgpu:fix scheduler hw reset&recovery
>
> Change-Id: I39e0b77029d22dc3fb37e2f19da699647ae96aad
> Signed-off-by: Monk Liu <Monk.Liu at amd.com>
> ---
>   drivers/gpu/drm/amd/scheduler/gpu_scheduler.c | 12 ++++++++++++
>   1 file changed, 12 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
> index ffe1f85..73dd5a7 100644
> --- a/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
> +++ b/drivers/gpu/drm/amd/scheduler/gpu_scheduler.c
> @@ -384,6 +384,13 @@ void amd_sched_hw_job_reset(struct amd_gpu_scheduler *sched)
>   	struct amd_sched_job *s_job;
>   
>   	spin_lock(&sched->job_list_lock);
> +	s_job = list_first_entry_or_null(&sched->ring_mirror_list,
> +					 struct amd_sched_job, node);
> +	if (!s_job) {
> +		spin_unlock(&sched->job_list_lock);
> +		return;
> +	}
> +
>   	list_for_each_entry_reverse(s_job, &sched->ring_mirror_list, node) {
>   		if (fence_remove_callback(s_job->s_fence->parent, &s_job->s_fence->cb)) {
>   			fence_put(s_job->s_fence->parent);
> @@ -405,6 +412,11 @@ void amd_sched_job_recovery(struct amd_gpu_scheduler *sched)
>   	if (s_job && sched->timeout != MAX_SCHEDULE_TIMEOUT)
>   		schedule_delayed_work(&s_job->work_tdr, sched->timeout);
>   
> +	if (!s_job) {
> +		spin_unlock(&sched->job_list_lock);
> +		return;
> +	}
> +
>   	list_for_each_entry_safe(s_job, tmp, &sched->ring_mirror_list, node) {
>   		struct amd_sched_fence *s_fence = s_job->s_fence;
>   		struct fence *fence;