Intel Adds Soft-Pinning Support To DRM Library

Intel recently added soft-pin support to their code within the DRM library (libdrm).

In terms of what Softpin is about, the work by Intel's Michał Winiarski explains, "Softpin allows userspace to take greater control of GPU virtual address space and eliminates the need of relocations. It can also be used to mirror addresses between GPU and CPU (shared virtual memory). Calls to drm_intel_bo_emit_reloc are still required to build the list of drm_i915_gem_exec_objects at exec time, but no entries in relocs are created. Self-relocs don't make any sense for softpinned objects and can indicate a programming errors, thus are forbidden."

Intel soft-pinning support landed with this commit and will be found in the next libdrm release. Soft-pinning support across the Intel driver stack has been in the works for several months.