[PATCH 4/5] drm/v3d: Create function to update a set of GPU stats

[Chema Casanova]

El 3/4/24 a las 22:24, Maíra Canal escribió:
> Given a set of GPU stats, that is, a `struct v3d_stats` related to a
> queue in a given context, create a function that can update all this set of
> GPU stats.
>
> Signed-off-by: Maíra Canal <mcanal at igalia.com>
> ---
>   drivers/gpu/drm/v3d/v3d_sched.c | 20 ++++++++++++--------
>   1 file changed, 12 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/v3d/v3d_sched.c b/drivers/gpu/drm/v3d/v3d_sched.c
> index ea5f5a84b55b..754107b80f67 100644
> --- a/drivers/gpu/drm/v3d/v3d_sched.c
> +++ b/drivers/gpu/drm/v3d/v3d_sched.c
> @@ -118,6 +118,16 @@ v3d_job_start_stats(struct v3d_job *job, enum v3d_queue queue)
>   	global_stats->start_ns = now;
>   }
>   
> +static void
> +v3d_stats_update(struct v3d_stats *stats)
> +{
> +	u64 now = local_clock();
I understand that with this change, we would be calling twice local_clock()
for each stat update, once for local and one for global stats. I don't know
the performance impact of the extra local_clock(), but I understand as 
you are
always updating global_stats after local_stats we would be losing the
correspondence that global_stats is the sum of all local_stats for all 
process.
With this approach, it will be always greater or equal.

Maybe it makes sense to pass an extra parameter now so save one
local_clock() and the sum of global and local stats is the same when you 
only
have one process running.


> +
> +	stats->enabled_ns += now - stats->start_ns;
> +	stats->jobs_sent++;
> +	stats->start_ns = 0;
> +}
> +
>   void
>   v3d_job_update_stats(struct v3d_job *job, enum v3d_queue queue)
>   {
> @@ -125,15 +135,9 @@ v3d_job_update_stats(struct v3d_job *job, enum v3d_queue queue)
>   	struct v3d_file_priv *file = job->file->driver_priv;
>   	struct v3d_stats *global_stats = &v3d->queue[queue].stats;
>   	struct v3d_stats *local_stats = &file->stats[queue];
> -	u64 now = local_clock();
> -
> -	local_stats->enabled_ns += now - local_stats->start_ns;
> -	local_stats->jobs_sent++;
> -	local_stats->start_ns = 0;
>   
> -	global_stats->enabled_ns += now - global_stats->start_ns;
> -	global_stats->jobs_sent++;
> -	global_stats->start_ns = 0;
> +	v3d_stats_update(local_stats);
> +	v3d_stats_update(global_stats);
>   }
>   
>   static struct dma_fence *v3d_bin_job_run(struct drm_sched_job *sched_job)