Hi,
On 09/11/2022 18:03, Thomas Hellström wrote:
Hi, Andi,
This has been on the list before (three times I think) and at that
point it (the guard pages) was NAK'd by Daniel as yet another
complication, and a VT-d
scanout workaround was implemented and pushed using a different
approach, initially outlined by Daniel.
I can't find this discussion and NAKs on the list - do you have a link?
Patch is 2ef6efa79fecd. Those suspend/resumes should now be fast.
So the initiator to re-start this series was actually the boot time is
failing KPIs by quite a margin. Which means we may need a way forward
after all. Especially if the most churny patch 1 was deemed okay, then I
don't see why the concept of guard pages should be a problem. But again,
I couldn't find the discussion you mention to read what were the
objections..
For 2ef6efa79fecd specifically. I only looked at it today - do you think
that the heuristic of checking one PTE and deciding all content was
preserved is safe? What if someone scribbled at random locations? On a
first thought it is making me a bit uncomfortable.
Regards,
Tvrtko
I then also discussed patch 1 separately with Dave Airlie and Daniel
and since both me and Dave liked it, Daniel OK'd it, but it never made
it upstream.
Just a short heads up on the history.
/Thomas
On Wed, 2022-11-09 at 18:40 +0100, Andi Shyti wrote:
Hi,
This series adds guards around vma's but setting a pages at the
beginning and at the end that work as padding.
The first user of the vma guard are scanout objects which don't
need anymore to add scratch to all the unused ggtt's and speeding
up up considerably the boot and resume by several hundreds of
milliseconds up to over a full second in slower machines.
Andi
Chris Wilson (3):
drm/i915: Wrap all access to i915_vma.node.start|size
drm/i915: Introduce guard pages to i915_vma
drm/i915: Refine VT-d scanout workaround
drivers/gpu/drm/i915/display/intel_fbdev.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_domain.c | 13 ++++
.../gpu/drm/i915/gem/i915_gem_execbuffer.c | 33 ++++++-----
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_shrinker.c | 2 +-
drivers/gpu/drm/i915/gem/i915_gem_tiling.c | 4 +-
.../gpu/drm/i915/gem/selftests/huge_pages.c | 2 +-
.../i915/gem/selftests/i915_gem_client_blt.c | 23 ++++----
.../drm/i915/gem/selftests/i915_gem_context.c | 15 +++--
.../drm/i915/gem/selftests/i915_gem_mman.c | 2 +-
.../drm/i915/gem/selftests/igt_gem_utils.c | 7 ++-
drivers/gpu/drm/i915/gt/gen7_renderclear.c | 2 +-
drivers/gpu/drm/i915/gt/intel_ggtt.c | 39 ++++--------
drivers/gpu/drm/i915/gt/intel_ggtt_fencing.c | 3 +-
drivers/gpu/drm/i915/gt/intel_renderstate.c | 2 +-
.../gpu/drm/i915/gt/intel_ring_submission.c | 2 +-
drivers/gpu/drm/i915/gt/selftest_engine_cs.c | 8 +--
drivers/gpu/drm/i915/gt/selftest_execlists.c | 18 +++---
drivers/gpu/drm/i915/gt/selftest_hangcheck.c | 15 ++---
drivers/gpu/drm/i915/gt/selftest_lrc.c | 16 ++---
.../drm/i915/gt/selftest_ring_submission.c | 2 +-
drivers/gpu/drm/i915/gt/selftest_rps.c | 12 ++--
.../gpu/drm/i915/gt/selftest_workarounds.c | 8 +--
drivers/gpu/drm/i915/i915_cmd_parser.c | 4 +-
drivers/gpu/drm/i915/i915_debugfs.c | 2 +-
drivers/gpu/drm/i915/i915_gem_gtt.h | 3 +-
drivers/gpu/drm/i915/i915_perf.c | 2 +-
drivers/gpu/drm/i915/i915_vma.c | 59 +++++++++++++----
--
drivers/gpu/drm/i915/i915_vma.h | 52 +++++++++++++++-
drivers/gpu/drm/i915/i915_vma_resource.c | 4 +-
drivers/gpu/drm/i915/i915_vma_resource.h | 17 ++++--
drivers/gpu/drm/i915/i915_vma_types.h | 3 +-
drivers/gpu/drm/i915/selftests/i915_request.c | 20 +++----
drivers/gpu/drm/i915/selftests/igt_spinner.c | 8 +--
34 files changed, 246 insertions(+), 160 deletions(-)
