Fix the following corner case:- Consider a 2M huge page SVM allocation, followed by prefetch call for the first 4K page. The whole range is initially mapped with single PTE. After the prefetch, this range gets split to first page + rest of the pages. Currently, the first page mapping is not updated on MI300A (APU) since page hasn't migrated. However, after range split PTE mapping it not valid.
Fix this by forcing page table update for the whole range when prefetch is called. Calling prefetch on APU doesn't improve performance. If all it deteriotes. However, functionality has to be supported. Suggested-by: Philip Yang <[email protected]> Signed-off-by: Harish Kasiviswanathan <[email protected]> --- drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c index c30dfb8ec236..d3d4f0d01653 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c @@ -766,14 +766,21 @@ svm_range_apply_attrs(struct kfd_process *p, struct svm_range *prange, { uint32_t i; int gpuidx; + struct kfd_node *node; for (i = 0; i < nattr; i++) { switch (attrs[i].type) { case KFD_IOCTL_SVM_ATTR_PREFERRED_LOC: prange->preferred_loc = attrs[i].value; + node = svm_range_get_node_by_id(prange, attrs[i].value); + if (node && node->adev->flags & AMD_IS_APU && !p->xnack_enabled) + *update_mapping = true; break; case KFD_IOCTL_SVM_ATTR_PREFETCH_LOC: prange->prefetch_loc = attrs[i].value; + node = svm_range_get_node_by_id(prange, attrs[i].value); + if (node && node->adev->flags & AMD_IS_APU && !p->xnack_enabled) + *update_mapping = true; break; case KFD_IOCTL_SVM_ATTR_ACCESS: case KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE: -- 2.34.1
