gpu/rfc/i915_scheduler.rst

15 	  no need to nit pick everything in the code, it just should be
20 	* Rework / get CI heathly for GuC submission in place as needed
21 * Merge new parallel submission uAPI
23 	  severe design issues in general, which is why we want to retire it no
28 	  a slot in a single execbuf IOCTL and the batches run on the GPU in
35 		  handled in DRM scheduler)
36 		* Resets / cancels hook in DRM scheduler
41 	* Execlists backend will minimum required to hook in the DRM scheduler
50 	* Port i915 priority inheritance / boosting feature in DRM scheduler
53 		* Will be an optional feature in the DRM scheduler
54 	* Remove in-order completion assumptions from DRM scheduler
75 * -1k to -1 Low priority
84 ----------------
86 * https://www.khronos.org/registry/vulkan/specs/1.2-extensions/html/chap5.html#devsandqueues-priori…
87 * https://spec.oneapi.com/level-zero/latest/core/api.html#ze-command-queue-priority-t
89 New parallel submission uAPI
92 whether a submission is a single context submit or parallel submit isn't known
94 contexts in parallel with the GuC the context must be explicitly registered with
95 N contexts and all N contexts must be submitted in a single command to the GuC.
97 bonding uAPI does. Hence the need for a new parallel submission interface. Also
102 The new parallel submission uAPI consists of 3 parts:
105 * A 'set_parallel' extension to configure contexts for parallel
107 * Extend execbuf2 IOCTL to support submitting N BBs in a single IOCTL
110 ------------------------------
111 Certain use cases require BBs to be placed on engine instances in logical order
112 (e.g. split-frame on gen11+). The logical mapping of engine instances can change
116 engines in logical order which is a new requirement compared to execlists.
125 A 'set_parallel' extension to configure contexts for parallel submission
126 ------------------------------------------------------------------------
127 The 'set_parallel' extension configures a slot for parallel submission of N BBs.
130 similar existing examples. Once a slot is configured for parallel submission the
131 execbuf2 IOCTL can be called submitting N BBs in a single IOCTL. Initially only
138 .. c:namespace-push:: rfc
140 .. kernel-doc:: include/uapi/drm/i915_drm.h
143 .. c:namespace-pop::
145 Extend execbuf2 IOCTL to support submitting N BBs in a single IOCTL
146 -------------------------------------------------------------------
148 submit N BBs in a single execbuf2 IOCTL. The BBs are either the last N objects
149 in the drm_i915_gem_exec_object2 list or the first N if I915_EXEC_BATCH_FIRST is