[Intel-gfx] [PATCH] drm/crc: Only report a single overflow when a CRC fd is opened

[Maarten Lankhorst]

Op 18-04-18 om 17:37 schreef Ville Syrjälä:
> On Wed, Apr 18, 2018 at 02:51:21PM +0200, Maarten Lankhorst wrote:
>> This reduces the amount of spam when you debug a CRC reading
>> program.
>>
>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
>> ---
>>  drivers/gpu/drm/drm_debugfs_crc.c | 9 ++++++++-
>>  include/drm/drm_debugfs_crc.h     | 3 ++-
>>  2 files changed, 10 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/drm_debugfs_crc.c b/drivers/gpu/drm/drm_debugfs_crc.c
>> index 9f8312137cad..5a052c511e62 100644
>> --- a/drivers/gpu/drm/drm_debugfs_crc.c
>> +++ b/drivers/gpu/drm/drm_debugfs_crc.c
>> @@ -139,6 +139,7 @@ static int crtc_crc_data_count(struct drm_crtc_crc *crc)
>>  static void crtc_crc_cleanup(struct drm_crtc_crc *crc)
>>  {
>>  	kfree(crc->entries);
>> +	crc->overflow = false;
>>  	crc->entries = NULL;
>>  	crc->head = 0;
>>  	crc->tail = 0;
>> @@ -391,8 +392,14 @@ int drm_crtc_add_crc_entry(struct drm_crtc *crtc, bool has_frame,
>>  	tail = crc->tail;
>>  
>>  	if (CIRC_SPACE(head, tail, DRM_CRC_ENTRIES_NR) < 1) {
>> +		bool overflow = crc->overflow;
> 'was_overflow' or something to indicate this is the old value?
>
>> +
>> +		crc->overflow = true;
>>  		spin_unlock(&crc->lock);
>> -		DRM_ERROR("Overflow of CRC buffer, userspace reads too slow.\n");
>> +
>> +		if (!overflow)
>> +			DRM_ERROR("Overflow of CRC buffer, userspace reads too slow.\n");
> would make this a bit less confusing perhaps. Now it reads as
> "if (no overflow) DRM_ERROR("we have an overflow");" which makes no
> sense on the first glance.
>
> Apart from that
> Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Thanks, fixed and pushed to drm-misc-next. :)