Tracing

i915_ppgtt_create and i915_ppgtt_release
i915_context_create and i915_context_free
switch_mm

This sections covers all things related to the tracepoints implemented in the i915 driver.

i915_ppgtt_create and i915_ppgtt_release

With full ppgtt enabled each process using drm will allocate at least one translation table. With these traces it is possible to keep track of the allocation and of the lifetime of the tables; this can be used during testing/debug to verify that we are not leaking ppgtts. These traces identify the ppgtt through the vm pointer, which is also printed by the i915_vma_bind and i915_vma_unbind tracepoints.

i915_context_create and i915_context_free

These tracepoints are used to track creation and deletion of contexts. If full ppgtt is enabled, they also print the address of the vm assigned to the context.

switch_mm

This tracepoint allows tracking of the mm switch, which is an important point in the lifetime of the vm in the legacy submission path. This tracepoint is called only if full ppgtt is enabled.