On 4/15/21 8:59 AM, Matthew Auld wrote: > Add a note about the two-step process. > > Suggested-by: Daniel Vetter <dan...@ffwll.ch> > Signed-off-by: Matthew Auld <matthew.a...@intel.com> > Cc: Joonas Lahtinen <joonas.lahti...@linux.intel.com> > Cc: Jordan Justen <jordan.l.jus...@intel.com> > Cc: Daniel Vetter <daniel.vet...@intel.com> > Cc: Kenneth Graunke <kenn...@whitecape.org> > Cc: Jason Ekstrand <ja...@jlekstrand.net> > Cc: Dave Airlie <airl...@gmail.com> > Cc: dri-de...@lists.freedesktop.org > Cc: mesa-...@lists.freedesktop.org > --- > include/uapi/drm/i915_drm.h | 57 ++++++++++++++++++++++++++++++------- > 1 file changed, 46 insertions(+), 11 deletions(-) > > diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h > index d9c954a5a456..ef36f1a0adde 100644 > --- a/include/uapi/drm/i915_drm.h > +++ b/include/uapi/drm/i915_drm.h > @@ -2210,14 +2210,23 @@ struct drm_i915_perf_oa_config { > __u64 flex_regs_ptr; > }; > > +/** > + * struct drm_i915_query_item - An individual query for the kernel to > process. > + * > + * The behaviour is determined by the @query_id. Note that exactly what
Since we just had a big discussion about this on mesa-dev w.r.t. Mesa code and documentation... does the kernel have a policy about which flavor (pun intended) of English should be used? > + * @data_ptr is also depends on the specific @query_id. > + */ > struct drm_i915_query_item { > + /** @query_id: The id for this query */ > __u64 query_id; > #define DRM_I915_QUERY_TOPOLOGY_INFO 1 > #define DRM_I915_QUERY_ENGINE_INFO 2 > #define DRM_I915_QUERY_PERF_CONFIG 3 > /* Must be kept compact -- no holes and well documented */ > > - /* > + /** > + * @length: > + * > * When set to zero by userspace, this is filled with the size of the > * data to be written at the data_ptr pointer. The kernel sets this > * value to a negative value to signal an error on a particular query > @@ -2225,21 +2234,26 @@ struct drm_i915_query_item { > */ > __s32 length; > > - /* > + /** > + * @flags: > + * > * When query_id == DRM_I915_QUERY_TOPOLOGY_INFO, must be 0. > * > * When query_id == DRM_I915_QUERY_PERF_CONFIG, must be one of the > - * following : > - * - DRM_I915_QUERY_PERF_CONFIG_LIST > - * - DRM_I915_QUERY_PERF_CONFIG_DATA_FOR_UUID > - * - DRM_I915_QUERY_PERF_CONFIG_FOR_UUID > + * following: > + * > + * - DRM_I915_QUERY_PERF_CONFIG_LIST > + * - DRM_I915_QUERY_PERF_CONFIG_DATA_FOR_UUID > + * - DRM_I915_QUERY_PERF_CONFIG_FOR_UUID > */ > __u32 flags; > #define DRM_I915_QUERY_PERF_CONFIG_LIST 1 > #define DRM_I915_QUERY_PERF_CONFIG_DATA_FOR_UUID 2 > #define DRM_I915_QUERY_PERF_CONFIG_DATA_FOR_ID 3 > > - /* > + /** > + * @data_ptr: > + * > * Data will be written at the location pointed by data_ptr when the > * value of length matches the length of the data to be written by the > * kernel. > @@ -2247,16 +2261,37 @@ struct drm_i915_query_item { > __u64 data_ptr; > }; > > +/** > + * struct drm_i915_query - Supply an array of drm_i915_query_item for the > kernel > + * to fill out. > + * > + * Note that this is generally a two step process for each > drm_i915_query_item > + * in the array: > + * > + * 1.) Call the DRM_IOCTL_I915_QUERY, giving it our array of > + * drm_i915_query_item, with drm_i915_query_item.size set to zero. The > + * kernel will then fill in the size, in bytes, which tells userspace how > + * memory it needs to allocate for the blob(say for an array of > + * properties). > + * > + * 2.) Next we call DRM_IOCTL_I915_QUERY again, this time with the > + * drm_i915_query_item.data_ptr equal to our newly allocated blob. Note > + * that the i915_query_item.size should still be the same as what the > + * kernel previously set. At this point the kernel can fill in the blob. > + * > + */ > struct drm_i915_query { > + /** @num_items: The number of elements in the @items_ptr array */ > __u32 num_items; > > - /* > - * Unused for now. Must be cleared to zero. > + /** > + * @flags: Unused for now. Must be cleared to zero. > */ > __u32 flags; > > - /* > - * This points to an array of num_items drm_i915_query_item structures. > + /** > + * @items_ptr: This points to an array of num_items drm_i915_query_item > + * structures. > */ > __u64 items_ptr; > }; > _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx