On 2/17/25 20:11, Dmitry Osipenko wrote:
> On 2/11/25 19:31, Christian König wrote:
>> The fence_value_str and timeline_value_str callbacks were just an
>> unnecessary abstraction in the SW sync implementation.
>>
>> The only caller of those callbacks already knew that the fence in
>> questions is a timeline_fence. So print the values directly instead
>> of using a redirection.
>>
>> Additional to that remove the implementations from virtgpu and vgem.
>> As far as I can see those were never used in the first place.
>>
>> Signed-off-by: Christian König <christian.koenig@xxxxxxx>
>> ---
>> drivers/dma-buf/sw_sync.c | 16 ----------------
>> drivers/dma-buf/sync_debug.c | 21 ++-------------------
>> drivers/gpu/drm/vgem/vgem_fence.c | 15 ---------------
>> drivers/gpu/drm/virtio/virtgpu_fence.c | 16 ----------------
>> include/linux/dma-fence.h | 21 ---------------------
>> 5 files changed, 2 insertions(+), 87 deletions(-)
>>
>> diff --git a/drivers/dma-buf/sw_sync.c b/drivers/dma-buf/sw_sync.c
>> index f5905d67dedb..849280ae79a9 100644
>> --- a/drivers/dma-buf/sw_sync.c
>> +++ b/drivers/dma-buf/sw_sync.c
>> @@ -173,20 +173,6 @@ static bool timeline_fence_signaled(struct dma_fence *fence)
>> return !__dma_fence_is_later(fence->seqno, parent->value, fence->ops);
>> }
>>
>> -static void timeline_fence_value_str(struct dma_fence *fence,
>> - char *str, int size)
>> -{
>> - snprintf(str, size, "%lld", fence->seqno);
>> -}
>> -
>> -static void timeline_fence_timeline_value_str(struct dma_fence *fence,
>> - char *str, int size)
>> -{
>> - struct sync_timeline *parent = dma_fence_parent(fence);
>> -
>> - snprintf(str, size, "%d", parent->value);
>> -}
>> -
>> static void timeline_fence_set_deadline(struct dma_fence *fence, ktime_t deadline)
>> {
>> struct sync_pt *pt = dma_fence_to_sync_pt(fence);
>> @@ -208,8 +194,6 @@ static const struct dma_fence_ops timeline_fence_ops = {
>> .get_timeline_name = timeline_fence_get_timeline_name,
>> .signaled = timeline_fence_signaled,
>> .release = timeline_fence_release,
>> - .fence_value_str = timeline_fence_value_str,
>> - .timeline_value_str = timeline_fence_timeline_value_str,
>> .set_deadline = timeline_fence_set_deadline,
>> };
>>
>> diff --git a/drivers/dma-buf/sync_debug.c b/drivers/dma-buf/sync_debug.c
>> index 237bce21d1e7..270daae7d89a 100644
>> --- a/drivers/dma-buf/sync_debug.c
>> +++ b/drivers/dma-buf/sync_debug.c
>> @@ -82,25 +82,8 @@ static void sync_print_fence(struct seq_file *s,
>> seq_printf(s, "@%lld.%09ld", (s64)ts64.tv_sec, ts64.tv_nsec);
>> }
>>
>> - if (fence->ops->timeline_value_str &&
>> - fence->ops->fence_value_str) {
>> - char value[64];
>> - bool success;
>> -
>> - fence->ops->fence_value_str(fence, value, sizeof(value));
>> - success = strlen(value);
>> -
>> - if (success) {
>> - seq_printf(s, ": %s", value);
>> -
>> - fence->ops->timeline_value_str(fence, value,
>> - sizeof(value));
>> -
>> - if (strlen(value))
>> - seq_printf(s, " / %s", value);
>> - }
>> - }
>> -
>> + seq_printf(s, ": %lld", fence->seqno);
>> + seq_printf(s, " / %d", parent->value);
>> seq_putc(s, '\n');
>> }
>>
>> diff --git a/drivers/gpu/drm/vgem/vgem_fence.c b/drivers/gpu/drm/vgem/vgem_fence.c
>> index e15754178395..5298d995faa7 100644
>> --- a/drivers/gpu/drm/vgem/vgem_fence.c
>> +++ b/drivers/gpu/drm/vgem/vgem_fence.c
>> @@ -53,25 +53,10 @@ static void vgem_fence_release(struct dma_fence *base)
>> dma_fence_free(&fence->base);
>> }
>>
>> -static void vgem_fence_value_str(struct dma_fence *fence, char *str, int size)
>> -{
>> - snprintf(str, size, "%llu", fence->seqno);
>> -}
>> -
>> -static void vgem_fence_timeline_value_str(struct dma_fence *fence, char *str,
>> - int size)
>> -{
>> - snprintf(str, size, "%llu",
>> - dma_fence_is_signaled(fence) ? fence->seqno : 0);
>> -}
>> -
>> static const struct dma_fence_ops vgem_fence_ops = {
>> .get_driver_name = vgem_fence_get_driver_name,
>> .get_timeline_name = vgem_fence_get_timeline_name,
>> .release = vgem_fence_release,
>> -
>> - .fence_value_str = vgem_fence_value_str,
>> - .timeline_value_str = vgem_fence_timeline_value_str,
>> };
>>
>> static void vgem_fence_timeout(struct timer_list *t)
>> diff --git a/drivers/gpu/drm/virtio/virtgpu_fence.c b/drivers/gpu/drm/virtio/virtgpu_fence.c
>> index f28357dbde35..44c1d8ef3c4d 100644
>> --- a/drivers/gpu/drm/virtio/virtgpu_fence.c
>> +++ b/drivers/gpu/drm/virtio/virtgpu_fence.c
>> @@ -49,26 +49,10 @@ static bool virtio_gpu_fence_signaled(struct dma_fence *f)
>> return false;
>> }
>>
>> -static void virtio_gpu_fence_value_str(struct dma_fence *f, char *str, int size)
>> -{
>> - snprintf(str, size, "[%llu, %llu]", f->context, f->seqno);
>> -}
>> -
>> -static void virtio_gpu_timeline_value_str(struct dma_fence *f, char *str,
>> - int size)
>> -{
>> - struct virtio_gpu_fence *fence = to_virtio_gpu_fence(f);
>> -
>> - snprintf(str, size, "%llu",
>> - (u64)atomic64_read(&fence->drv->last_fence_id));
>> -}
>> -
>> static const struct dma_fence_ops virtio_gpu_fence_ops = {
>> .get_driver_name = virtio_gpu_get_driver_name,
>> .get_timeline_name = virtio_gpu_get_timeline_name,
>> .signaled = virtio_gpu_fence_signaled,
>> - .fence_value_str = virtio_gpu_fence_value_str,
>> - .timeline_value_str = virtio_gpu_timeline_value_str,
>> };
>>
>> struct virtio_gpu_fence *virtio_gpu_fence_alloc(struct virtio_gpu_device *vgdev,
>> diff --git a/include/linux/dma-fence.h b/include/linux/dma-fence.h
>> index e230af0d123f..8778e2d758da 100644
>> --- a/include/linux/dma-fence.h
>> +++ b/include/linux/dma-fence.h
>> @@ -238,27 +238,6 @@ struct dma_fence_ops {
>> */
>> void (*release)(struct dma_fence *fence);
>>
>> - /**
>> - * @fence_value_str:
>> - *
>> - * Callback to fill in free-form debug info specific to this fence, like
>> - * the sequence number.
>> - *
>> - * This callback is optional.
>> - */
>> - void (*fence_value_str)(struct dma_fence *fence, char *str, int size);
>> -
>> - /**
>> - * @timeline_value_str:
>> - *
>> - * Fills in the current value of the timeline as a string, like the
>> - * sequence number. Note that the specific fence passed to this function
>> - * should not matter, drivers should only use it to look up the
>> - * corresponding timeline structures.
>> - */
>> - void (*timeline_value_str)(struct dma_fence *fence,
>> - char *str, int size);
>> -
>> /**
>> * @set_deadline:
>> *
>
> Look okay. No sure if Google's perfetto makes use of the syncfile
> debugfs and then this change may brake the userspace parser for
> virtio-gpu, but debugfs isn't ABI and perfetto will adapt if needed.
>
> +cc Rob Clark for visibility
>
> Reviewed-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx>
and +Gurchetan Singh for even more visibility
--
Best regards,
Dmitry
