On 9/13/19 12:53 PM, Koenig, Christian wrote:
Am 12.09.19 um 20:38 schrieb Thomas Hellström (VMware):
From: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
Commit 4daa4fba3a38 ("gpu: drm: ttm: Adding new return type vm_fault_t")
broke TTM prefaulting. Since vmf_insert_mixed() typically always returns
VM_FAULT_NOPAGE, prefaulting stops after the second PTE.
Restore (almost) the original behaviour. Unfortunately we can no longer
with the new vm_fault_t return type determine whether a prefaulting
PTE insertion hit an already populated PTE, and terminate the insertion
loop. Instead we continue with the pre-determined number of prefaults.
Fixes: 4daa4fba3a38 ("gpu: drm: ttm: Adding new return type vm_fault_t")
Cc: Souptick Joarder <jrdr.linux@xxxxxxxxx>
Cc: Christian König <christian.koenig@xxxxxxx>
Signed-off-by: Thomas Hellstrom <thellstrom@xxxxxxxxxx>
Reviewed-by: Christian König <christian.koenig@xxxxxxx>
Going to pick that up when Alex rebases our upstream branch.
Christian.
---
drivers/gpu/drm/ttm/ttm_bo_vm.c | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/ttm/ttm_bo_vm.c b/drivers/gpu/drm/ttm/ttm_bo_vm.c
index 5a580adeb9d1..aa18e8a53727 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_vm.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_vm.c
@@ -290,15 +290,13 @@ vm_fault_t ttm_bo_vm_fault_reserved(struct vm_fault *vmf,
else
ret = vmf_insert_pfn(&cvma, address, pfn);
- /*
- * Somebody beat us to this PTE or prefaulting to
- * an already populated PTE, or prefaulting error.
- */
-
- if (unlikely((ret == VM_FAULT_NOPAGE && i > 0)))
- break;
- else if (unlikely(ret & VM_FAULT_ERROR))
- goto out_io_unlock;
+ /* Never error on prefaulted PTEs */
+ if (unlikely((ret & VM_FAULT_ERROR))) {
+ if (i == 0)
+ goto out_io_unlock;
+ else
We could perhaps skip that else. Let me know if you want me to respin.
/Thomas
+ break;
+ }
address += PAGE_SIZE;
if (unlikely(++page_offset >= page_last))
_______________________________________________
dri-devel mailing list
dri-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/dri-devel
