[PATCH hmm 3/5] drm/amdgpu: remove dead code after hmm_range_fault()

From: Jason Gunthorpe
Date: Tue Apr 21 2020 - 20:21:54 EST


From: Jason Gunthorpe <jgg@xxxxxxxxxxxx>

Since amdgpu does not use the snapshot mode of hmm_range_fault() a
successful return already proves that all entries in the pfns are
HMM_PFN_VALID, there is no need to check the return result of
hmm_device_entry_to_page().

Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 16 ++++++----------
1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index efc1329a019127..bff8e64701a547 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -862,17 +862,13 @@ int amdgpu_ttm_tt_get_user_pages(struct amdgpu_bo *bo, struct page **pages)
goto out_free_pfns;
}

- for (i = 0; i < ttm->num_pages; i++) {
- /* FIXME: The pages cannot be touched outside the notifier_lock */
+ /*
+ * Due to default_flags, all pages are HMM_PFN_VALID or
+ * hmm_range_fault() fails. FIXME: The pages cannot be touched outside
+ * the notifier_lock, and mmu_interval_read_retry() must be done first.
+ */
+ for (i = 0; i < ttm->num_pages; i++)
pages[i] = hmm_device_entry_to_page(range, range->pfns[i]);
- if (unlikely(!pages[i])) {
- pr_err("Page fault failed for pfn[%lu] = 0x%llx\n",
- i, range->pfns[i]);
- r = -ENOMEM;
-
- goto out_free_pfns;
- }
- }

gtt->range = range;
mmput(mm);
--
2.26.0