GPU use-cases for mmu_interval_notifiers with hmm often involve
starting a gpu operation and then waiting for it to complete.
These operations are typically context preemption or TLB flushing.
With single-pass notifiers per GPU this doesn't scale in
multi-gpu scenarios. In those scenarios we'd want to first start
preemption- or TLB flushing on all GPUs and as a second pass wait
for them to complete.
One can do this on per-driver basis multiplexing per-driver
notifiers but that would mean sharing the notifier "user" lock
across all GPUs and that doesn't scale well either, so adding support
for two-pass in the core appears like the right choice.
So this series does that, with pach 1 implementing the core support
and also describes the choices made.
The rest of the patches implements a POC with drm_gpusvm, but this
will also come in handy for things like userptr where waiting for
bind completion, starting of preemption and waiting for
preemption completion can pe pipelined across GPUs.
Cc: Matthew Brost <[email protected]>
Cc: Jason Gunthorpe <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Simona Vetter <[email protected]>
Cc: Dave Airlie <[email protected]>
Cc: Alistair Popple <[email protected]>
Cc: <[email protected]>
Cc: <[email protected]>
Cc: <[email protected]>
Matthew Brost (5):
drm/gpusvm, drm/xe: Update GPU SVM / Xe to twopass MMU notifier
drm/gpusvm: Add drm_gpusvm_in_notifier_* helpers
drm/xe: Skip waiting on unarmed fences in
xe_gt_tlb_invalidation_fence_wait
drm/xe: Add fences argument to xe_vm_range_tilemask_tlb_invalidation
drm/xe: Implement two pass MMU notifiers for SVM
Thomas Hellström (1):
mm/mmu_notifier: Allow two-pass struct mmu_interval_notifiers
drivers/gpu/drm/drm_gpusvm.c | 18 +++--
drivers/gpu/drm/xe/xe_gt_tlb_invalidation.h | 3 +-
drivers/gpu/drm/xe/xe_svm.c | 83 +++++++++++++++++----
drivers/gpu/drm/xe/xe_vm.c | 26 ++++---
drivers/gpu/drm/xe/xe_vm.h | 6 +-
include/drm/drm_gpusvm.h | 33 ++++++--
include/linux/mmu_notifier.h | 42 +++++++++++
mm/mmu_notifier.c | 63 +++++++++++++---
8 files changed, 224 insertions(+), 50 deletions(-)
--
2.50.1
