[Intel-gfx] [PATCH v8 6/6] drm/i915: expose rcs topology through query uAPI

[Lionel Landwerlin]

On 17/01/18 15:50, Lionel Landwerlin wrote:
> On 17/01/18 15:39, Lionel Landwerlin wrote:
>> With the introduction of asymmetric slices in CNL, we cannot rely on
>> the previous SUBSLICE_MASK getparam to tell userspace what subslices
>> are available. Here we introduce a more detailed way of querying the
>> Gen's GPU topology that doesn't aggregate numbers.
>>
>> This is essential for monitoring parts of the GPU with the OA unit,
>> because counters need to be normalized to the number of
>> EUs/subslices/slices. The current aggregated numbers like EU_TOTAL do
>> not gives us sufficient information.
>>
>> As a bonus we can draw representations of the GPU :
>>
>>          https://imgur.com/a/vuqpa
>>
>> v2: Rename uapi struct s/_mask/_info/ (Tvrtko)
>>      Report max_slice/subslice/eus_per_subslice rather than strides 
>> (Tvrtko)
>>      Add uapi macros to read data from *_info structs (Tvrtko)
>>
>> v3: Use !!(v & DRM_I915_BIT()) for uapi macros instead of custom 
>> shifts (Tvrtko)
>>
>> v4: factorize query item writting (Tvrtko)
>>      tweak uapi struct/define names (Tvrtko)
>>
>> v5: Replace ALIGN() macro (Chris)
>>
>> v6: Updated uapi comments (Tvrtko)
>>      Moved flags != 0 checks into vfuncs (Tvrtko)
>>
>> Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
>> ---
>>   drivers/gpu/drm/i915/i915_query.c | 105 
>> ++++++++++++++++++++++++++++++++++++++
>>   include/uapi/drm/i915_drm.h       |  68 ++++++++++++++++++++++++
>>   2 files changed, 173 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/i915/i915_query.c 
>> b/drivers/gpu/drm/i915/i915_query.c
>> index 5aa886313cf9..5d1386db8e7b 100644
>> --- a/drivers/gpu/drm/i915/i915_query.c
>> +++ b/drivers/gpu/drm/i915/i915_query.c
>> @@ -25,8 +25,113 @@
>>   #include "i915_drv.h"
>>   #include <uapi/drm/i915_drm.h>
>>   +static int copy_query_data(struct drm_i915_query_item *query_item,
>> +               const void *item_ptr, u32 item_length,
>> +               const void *data_ptr, u32 data_length)
>> +{
>> +    u32 total_length = item_length + data_length;
>> +
>> +    BUG_ON(add_overflows(item_length, data_length));
>> +
>> +    if (query_item->length == 0)
>> +        return total_length;
>> +
>> +    if (query_item->length < total_length)
>> +        return -EINVAL;
>> +
>> +    if (copy_to_user(u64_to_user_ptr(query_item->data_ptr),
>> +             item_ptr, item_length))
>> +        return -EFAULT;
>> +
>> +    if (copy_to_user(u64_to_user_ptr(query_item->data_ptr + 
>> item_length),
>> +             data_ptr, data_length))
>> +        return -EFAULT;
>> +
>
> Dammit... Forgot some overflow checking here. 

Fixed locally.